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usmle-12151

A 62-year-old man comes to his primary care physician with a 3-month history of insomnia and severe work anxiety. He says that he is unable to retire because he has no financial resources; however, the stress level at his work has been causing him to have worsening performance and he is afraid of being fired. He thinks that he would be able to resume work normally if he was able to decrease his level of anxiety. His physician prescribes him a trial 1-month regimen of benzodiazepine therapy and schedules a follow-up appointment to see whether this treatment has been effective. Three weeks later, the patient's wife calls and says "My husband was fired from work and it's your fault for prescribing that medication! I know he must have been taking too much of that drug. Don't you know that he had a horrible problem with drug abuse in his 30s?" Which of the following is the most appropriate first action for the physician to take?

usmle-12152

A 15-year-old boy is brought to the emergency department with a 30 minute history of difficulty breathing. He was playing basketball in gym class when he suddenly felt pain in the right side of his chest that got worse when he tried to take a deep breath. Physical exam reveals a tall, thin boy taking rapid shallow breaths. There are decreased breath sounds in the right lung fields and the right chest is hyperresonant to percussion. Which of the following is true of the lesions that would most likely be seen in this patient's lungs?

usmle-12153

An 8-year-old boy is brought to his pediatrician by his mother because she is worried about whether he is becoming ill. Specifically, he has been sent home from school six times in the past month because of headaches and abdominal pain. In fact, he has been in the nurse's office almost every day with various symptoms. These symptoms started when the family moved to an old house in another state about 2 months ago. Furthermore, whenever he is taken care of by a babysitter he also has these symptoms. Despite these occurrences, the boy never seems to have any problems at home with his parents. Which of the following treatments would likely be effective for this patient?

usmle-12154

A 35-year-old healthy woman with no prenatal care or screening gives birth to a newborn girl via spontaneous vaginal delivery. On examination of the newborn you note redundant neck skin, a webbed neck, and widely spaced nipples. Furthermore, the newborns feet are shown in Figure A. What is the reason for this patients foot swelling?

usmle-12155

A 30-year-old female presents to the fertility clinic with a history of multiple miscarriages. She is frustrated as she and her partner have been trying to conceive for over 2 years. Her medical history is unremarkable and her physical exam is within normal limits. A hysterosalpingogram is performed (Figure A). What process resulted in this abnormality?

usmle-12156

A 53-year-old woman presents to her primary care physician with joint pain. She reports a 6-month history of progressive pain in her hands that is worse around her knuckles. The pain is symmetric bilaterally and seems to improve after she starts working in the morning at her job in a local grocery store. She has also lost 10 pounds over the past 6 months despite no changes in her weight or exercise regimen. Her past medical history is notable for seasonal allergies, hypertension, and intermittent constipation. She takes losartan and a laxative as needed. She had adolescent idiopathic scoliosis as a child and underwent a spinal fusion at the age of 14. She does not smoke or drink alcohol. Her temperature is 98.6°F (37°C), blood pressure is 135/75 mmHg, pulse is 92/min, and respirations are 16/min. On examination, she appears well and is appropriately interactive. Strength is 5/5 and sensation to light touch is intact in the bilateral upper and lower extremities. An examination of her hands demonstrates symmetric swelling of the metacarpophalangeal joints bilaterally. This patient’s condition is most strongly characterized by which of the following?

usmle-12157

A 37-year-old man presents to his primary care physician because he has had constipation for the last several weeks. He has also been feeling lethargic and complains that this winter has been particularly cold. He also complains that he has been gaining weight despite no change in his normal activities. He reveals that two months prior to presentation he had what felt like the flu for which he took tylenol and did not seek medical attention. Several days after this he developed anterior neck pain. Which of the following findings would most likely be seen on biopsy of this patient's abnormality?

usmle-12158

A 64-year-old man with a 30-year smoking history presents to the physician for the first time in fifteen years with new onset right eyelid droop. On physical exam you notice a fixed right pupil of 2mm. As part of an initial workup, a chest radiograph (CXR) is performed, which demonstrates the findings in Figure A. What other physical exam abnormality would be most commonly associated with this finding on CXR?

usmle-12159

An 19-year-old woman presents to her primary care physician because she has been feeling increasingly lethargic over the last 6 months. Specifically, she says that she feels tired easily and has been cold even though she is wearing lots of layers. Her medical history is significant for seasonal allergies but is otherwise unremarkable. When prompted, she also says that she has a hard time swallowing food though she has no difficulty drinking liquids. Physical exam reveals a midline mass in her neck. Which of the following structures would most likely be seen if this patient's mass was biopsied?

usmle-12160

A 20-year-old female presents complaining of a persistent nonproductive cough and headache that has gradually developed over the past week. Chest radiograph demonstrates bilateral diffuse interstitial infiltrates. No pathologic organisms are noted on Gram stain of the patient’s sputum. Which of the following findings is most likely to be found upon laboratory evaluation?

usmle-12161

A 33-year-old G0P0 female presents to her gynecologist for a new patient visit. She has not visited a gynecologist for several years due to her fear of doctors. She reports that she feels well and has no complaints. She has been monogamous with a male partner for the past five years and they use barrier protection consistently. Her past medical history is notable for pelvic inflammatory disease in her early 20’s and she has a 15 pack-year smoking history. A bimanual examination reveals no cervical motion tenderness or adnexal tenderness. A pap smear is performed and reveals koilocytes. She subsequently undergoes a cone biopsy which is shown in Figure A. The changes seen in Figure A are most consistent with which of the following?

usmle-12162

A 52-year-old male presents to his primary care physician for cough for the past 2 months. The patient has a history of COPD and a 20 pack-year smoking history. The physician immediately notices a change in the patient’s facial appearance (Figure A). On physical exam, the patient’s left pupil is 4 mm while the right pupil is 2 mm. The patient is unsure if he has experienced any changes in facial sweating. A chest radiograph is obtained as follows (Figure B). Which of the following is the underlying cause of the patient’s physical exam findings?

usmle-12163

A microbiology graduate student was given a swab containing an unknown bacteria that caused an ear infection in a seven-year-old girl. The student identified the bacteria as a gram-positive, catalase-negative cocci producing green rings around the colonies when grown on blood agar. Which of the following characteristics is associated with this bacteria?

usmle-12164

A 32-year-old woman presents to the emergency department with abdominal pain and vaginal discharge. She gave birth to a healthy baby boy three days prior to presentation. Since then, she has been feeling sick, and she is concerned that she has been getting worse over time. On presentation, her temperature is 100.7°F (38.1°C), blood pressure is 115/78 mmHg, pulse is 105/min, and respirations are 14/min. Physical exam reveals abdominal discomfort with uterine tenderness, and laboratory results show elevated white blood cell count with many plasma cells. The most likely cause of this patient's disorder has which of the following characteristics?

usmle-12165

A 2-year-old boy is brought to his pediatrician for evaluation of a tender red big toe. His mother also notes that she has seen him recently starting to bite his own fingers and also exhibits spasms of muscle tightness. She reports that his diapers often contain the substance shown in the photograph. On exam he is noted to be significantly developmentally delayed as he is neither walking nor talking. Which of the following would be the first-line pharmacologic treatment for this patient's disorder?

usmle-12166

A 58-year-old man presents to his primary care physician with a 3-week history of increasing pain in his legs and feet. Specifically, he says that he has been getting electric shock sensations that started in his feet, but have progressed up his leg. In addition, the pain is accompanied by numbness and tingling in his hands and feet bilaterally. His past medical history is significant for poorly controlled type 2 diabetes mellitus. Given these symptoms, his physician prescribes a new drug to help him cope with these symptoms. Which of the following is the mechanism of action for the medication that was most likely prescribed in this case?

usmle-12167

A parent-teacher conference is called to discuss the behavior of a 9 year-old boy. According to the boy's teacher, he has become progressively more disruptive during class. When asked to help clean up or read out-loud, he replies with "You're not the boss of me." or "You can't make me." He refuses to participate in gym class, but will play the same games during recess. He gets along with and is well-liked by his peers. His mother reports that her son can "sometimes be difficult," but he is helpful around the house and is very good playing with his 7-year-old sister. What is the most likely diagnosis?

usmle-12168

A 38-year-old man presents to the clinic for complaints of abdominal pain and diarrhea. He reports a long-standing history of the symptoms except for the time when he attempted a carbohydrate-free diet 5 years ago. The pain is described as stabbing, diffuse, 8/10, and is especially worse following food intake. Recently, he noticed some numbness and tingling of his feet but denies any bloody stool, nausea, vomiting, fevers, weight loss, or focal neurological deficits. What histopathological findings would you expect to find in this patient?

usmle-12169

A 76-year-old woman presents to the clinic complaining of blood on her underwear. She denies any clear precipitating factor or trauma to the area, but 2 weeks ago she noticed some reddish-brown stains on her undergarments. This has been happening intermittently since then. She denies pain, abnormal discharge, abnormal odors, urinary symptoms, or gastrointestinal symptoms. Her past medical history is unremarkable and she has had regular pap smears, the most recent being 10 years ago. A pelvic examination is performed and a small protrusion from the vaginal wall is visualized. A vaginal biopsy is done and its results are shown in Figure A. Which of the following is associated with this patient’s condition?

usmle-12170

An 11-year-old girl is brought to the emergency department after she fell during a dance class. She was unable to stand after the accident and has a painful and swollen knee. On presentation she says that she has had 2 previous swollen joints as well as profuse bleeding after minor cuts. Based on her presentation, a panel of bleeding tests is obtained with the following results: Bleeding time: 11 minutes Prothrombin time: 12 seconds Partial thromboplastin time: 52 seconds Which of the following treatments would be most effective in treating this patient's condition?

usmle-12171

A 31-year-old African American woman presents to her primary care provider complaining of stiff, painful fingers. She reports that her symptoms started 2 years ago and have gradually worsened. Her pain is not relieved by ibuprofen or acetaminophen. She is most concerned about having occasional episodes in which her fingers become extremely painful and turn white then pale blue. Her past medical history is notable for hypertension but she has previously refused to take any medication. She works as a postal worker and spends most of her time outside. Physical examination reveals induration of her digits with loss of skin fold wrinkles. She has limited finger range of motion. She would like to know if she can do anything to address her intermittent finger pain as it is affecting her ability to work outside in the cold. Which of the following medications is most appropriate to address this patient’s concerns?

usmle-12172

A 41-year-old Hispanic male presents to the emergency room complaining of heartburn. He does not have a primary care provider and has not seen a physician in over ten years. He reports gradually worsening retrosternal pain that has also been accompanied by painful and difficult swallowing for the past 3 months. He has also lost 15 pounds over the past 6 months without a change in diet or exercise patterns. The patient has a history of intravenous drug use but reports that he has been clean for the past two years. He was previously homeless for several years and was briefly incarcerated for drug possession. He has a 20-pack-year smoking history. He used to drink alcohol heavily but has been sober for the past two years. His temperature is 100.5°F (38.1°C), blood pressure is 130/85 mmHg, pulse is 90/min, and respirations are 20/min. Multiple imaging and lab tests are ordered. A double-contrast esophageal barium study is shown in Figure A. This patient should be tested for which of the following pathogens?

usmle-12173

A 47-year-old female with a history of poorly controlled type I diabetes mellitus and end-stage renal disease undergoes an allogeneic renal transplant. Her immediate post-operative period is unremarkable and she is discharged from the hospital on post-operative day 4. Her past medical history is also notable for major depressive disorder, obesity, and gout. She takes sertraline, allopurinol, and insulin. She does not smoke or drink alcohol. To decrease the risk of transplant rejection, her nephrologist adds a medication known to serve as a precursor to 6-mercaptopurine. Following initiation of this medication, which of the following toxicities should this patient be monitored for?

usmle-12174

A 48-year-old woman with alpha-1-antitrypsin deficiency undergoes a lung transplant. She tolerates the surgery well, but 3 years later develops inflammation and fibrosis in her terminal bronchioles. Which of the following best describes the pathophysiology of this patient's deterioration?

usmle-12175

A 24-year-old healthy male presents to the emergency room complaining of severe abdominal pain. He reports that he was playing rugby for his college team when he was tackled on his left side by a member of the opposing team. He is currently experiencing severe left upper abdominal pain and left shoulder pain. A review of his medical record reveals that he was seen by his primary care physician two weeks ago for mononucleosis. His temperature is 99°F (37.2°C), blood pressure is 90/50 mmHg, pulse is 130/min, and respirations are 26/min. He becomes increasingly lethargic over the course of the examination. He demonstrates exquisite tenderness to palpation over the left 8th, 9th, and 10th ribs as well as rebound tenderness in the abdomen. He is eventually stabilized and undergoes definitive operative management. After this patient recovers, which of the following is most likely to be found on a peripheral blood smear in this patient?

usmle-12176

A 43-year-old male presents to the emergency department with abdominal pain, distention, and vomiting. He states that he has not had a bowel movement in 4 days. On physical exam, vitals are stable and within normal limits. Abdominal exam shows a distended, tympanic abdomen that is tender to palpation without rebound or guarding. Laboratory studies are remarkable for a leukocytosis. Helical CT scan shows a small bowel obstruction with a transition point in ileum. The patient is stabilized with NPO, NGT decompression, and IV fluids. The following day, he is taken to the OR for exploratory laparotomy. The following is found on exploration (Figure A). The obstruction is resected, histology with H&E staining of the bowel segment is shown in Figure B. Which of the following would have been found in this patient prior to resection?

usmle-12177

A 61-year-old male presents to his primary care doctor with a six-month history of progressively worsening cough, shortness of breath, and 15-pound weight loss. Over the same time period, he has also started to notice occasional weakness in his legs that has made it difficult for him to stand up from his chair and climb stairs. The weakness appears to improve when he exercises at his local aerobics class. His past medical history is notable for hypertension and hyperlipidemia. He has smoked 2 packs of cigarettes per day for 35 years. Chest radiographs demonstrate a perihilar mass in his right lung. A biopsy of the lung lesion is shown. Which of the following is most likely true about this patient?

usmle-12178

A 15-year-old boy presents to his pediatrician concerned that he is not growing as well as his peers. He had previously grown 2 inches in the past year but is concerned that many of his friends are now taller than him. He reports eating a healthy diet and plays soccer recreationally. He admits to having increasingly frequent episodes of abdominal pain over the past 6 months and occasional loose stools. He also recently developed a rash, but he dismissed this as being acne. The boy's height is 65 inches (166 cm) and weighs 107 pounds (48.5 kg), unchanged from previous measurements last year. His current height is significantly lower than his mean parental height. Physical exam demonstrates a non-tender, non-distended abdomen with mildly increased bowel sounds. The boy's rash is pictured in Figure A. Which of the following is the next best step in management?

usmle-12179

A 7-year-old boy is brought in to clinic by his parents with a chief concern of poor performance in school. The parents were told by the teacher that the student often does not turn in assignments, and when he does they are partially complete. The child also often shouts out answers to questions and has trouble participating in class sports as he does not follow the rules. The parents of this child also note similar behaviors at home and have trouble getting their child to focus on any task such as reading. The child is even unable to watch full episodes of his favorite television show without getting distracted by other activities. The child begins a trial of behavioral therapy that fails. The physician then tries pharmacological therapy. Which of the following is most likely the mechanism of action of an appropriate treatment for this child's condition?

usmle-12180

A 59-year-old man is brought to the emergency department for changes in mental status. His wife noticed that since lunch time today, he has been “zoning out” and forgetting simple things such as where the bathroom is. She decided to call the ambulance as he got uncharacteristically violent during dinner when he threw his plate to the floor. The patient denies fevers, weight loss, chills, chest pain, or shortness of breath, but reports mild abdominal discomfort and some dark stools that he attributes to iron supplements. A physical examination demonstrates a moderate fluid wave of the abdomen and shaking of the hands while the wrists are extended. What is the mechanism of action of the medication that can treat this patient’s condition?

usmle-12181

A 54-year-old man with a history of hyperlipidemia presents to the emergency department complaining of left sided chest pain. He says the pain began 3 hours ago while he was cooking dinner in his kitchen. The pain radiates to his left arm and stomach. He also complains of feeling anxious and heart palpitations. Temperature is 98.7°F (37.1°C), blood pressure is 130/80 mmHg, pulse is 101/min, and respirations are 22/min. Inspection demonstrates a diffuse diaphoresis, and cardiac auscultation reveals an S4 gallop. Cardiac catheterization reveals occlusion of the left anterior descending artery, and a vascular stent is placed. The patient is discharged on aspirin, atorvastatin, and an antiplatelet medication. Which of the following is the mechanism of action of the most likely prescribed antiplatelet medication?

usmle-12182

A 32-year-old man presents to the emergency room with difficulty breathing and reports that he has had a productive cough for a few days. He has not had any fevers. He has no recent travel, has never smoked, and does not report any recent chills, weight-loss or night-sweats. He is married and monogamous, and denies any history of drug use. He notes that the color of his urine "does not look normal". On physical exam, his temperature is 98.8°F (37.1°C), blood pressure is 127/84 mmHg, respirations are 21/min, and pulse is 105/min. His pulmonary exam is remarkable for bilateral rales, and the tissues he is coughing into are covered in blood-tinged sputum. Chest radiograph hows bilateral infiltrates. His creatinine is 3.4 and urinalysis is positive for red blood cells. Renal biopsy is done, revealing crescentic glomerulonephritis and the photograph provided (see Figure A) shows the result of immunofluorescence study. The patient is then treated with emergency plasmapheresis. Which of the following diseases is most similar in pathophysiology to the patient's disorder?

usmle-12183

A 40-year-old woman presents to her primary care physician for a checkup. She has felt weaker lately and has lost some weight. She denies any urinary issues. Her BUN at her last visit 4 months ago was 45 mg/dL, and her creatinine was 2.0 mg/dL. Her laboratory studies this visit are seen below: Hemoglobin: 8 g/dL Hematocrit: 29% Leukocyte count: 9,500/mm^3 with normal differential Platelet count: 197,000/mm^3 Serum: Na+: 139 mEq/L Cl-: 100 mEq/L K+: 5.9 mEq/L HCO3-: 17 mEq/L BUN: 59 mg/dL Glucose: 99 mg/dL Creatinine: 2.3 mg/dL Ca2+: 9.0 mg/dL Which of the following is the most likely diagnosis?

usmle-12184

A 24-year-old woman presents to her primary care physician with a 3 day history of pain with urination. She says that this pain has been accompanied by abdominal pain as well as a feeling like she always needs to use the restroom. She has no past medical history and no family history that she can recall. She is currently sexually active with a new partner but has tested negative for sexually transmitted infections. Physical exam reveals suprapubic tenderness and urine culture reveals gram-positive cocci. Which of the following best describes the organism that is most likely causing this patient's symptoms?

usmle-12185

An 18-year-old man presents to the student health department at his university for recurrent palpitations. The patient had previously presented to the emergency department (ED) for sudden onset palpitations five months ago when he first started college. He had a negative cardiac workup in the ED and he was discharged with a 24-hour Holter monitor which was also negative. He has no history of any medical or psychiatric illnesses. The patient reports that since his initial ED visit, he has had several episodes of unprovoked palpitations associated with feelings of dread and lightheadedness though he cannot identify a particular trigger. Recently, he has begun sitting towards the back of the lecture halls so that he can “quickly escape and not make a scene” in case he gets an episode in class. Which of the following is the most likely diagnosis?

usmle-12186

A 38-year-old male is brought to the emergency department by ambulance after a motor vehicle collision. He is found to have a broken femur and multiple soft tissue injuries and is admitted to the hospital. During the hospital course, he is found to have lower extremity swelling, redness, and pain, so he is given an infusion of a medication. The intravenous medication is discontinued in favor of an oral medication in preparation for discharge; however, the patient leaves against medical advice prior to receiving the full set of instructions. The next day, the patient is found to have black lesions on his trunk and his leg. The protein involved in this patient's underlying abnormality most likely affects the function of which of the following factors?

usmle-12187

A 51-year-old man presents to his primary care physician with 3 months of increasing fatigue. He says that he has been feeling short of breath while walking to his office from the parking lot and is no longer able to participate in recreational activities that he enjoys such as hiking. His wife also comments that he has been looking very pale even though they spend a lot of time outdoors. His past medical history is significant for acute kidney injury after losing blood during a car accident as well as alcoholic hepatitis. Physical exam reveals conjunctival pallor, and a peripheral blood smear is obtained with the finding demonstrate in figure A. Which of the following is associated with the most likely cause of this patient's symptoms?

usmle-12188

A 7-year-old boy presents to the emergency department with several days of high fever accompanied by runny nose, cough, and red itchy eyes. Upon further history, you learn that the family is undocumented and has not had access to primary health services. Upon physical examination you see a red, slightly bumpy rash extending from the head to the mid-chest level. If you had examined this child a prior to the development of the rash, which of the following signs may you have observed?

usmle-12189

A 9-year-old boy is brought to the emergency department by ambulance due to difficulty breathing. On presentation he is found to be straining to breathe. Physical exam reveals bilateral prolonged expiratory wheezing, difficulty speaking, and belly breathing. Radiographs also reveal hyperinflation of the lungs. He is given oxygen as well as albuterol, which begins to reverse the flow limitation in the airway segments of this patient. The airway segment that is most susceptible to this type of flow limitation has which of the following characteristics?

usmle-12190

A 65-year-old man is brought to the emergency department by ambulance after falling during a hiking trip. He was hiking with friends when he fell off a 3 story ledge and was not able to be rescued until 6 hours after the accident. On arrival, he is found to have multiple lacerations as well as a pelvic fracture. His past medical history is significant for diabetes and benign prostatic hyperplasia, for which he takes metformin and prazosin respectively. Furthermore, he has a family history of autoimmune diseases. Selected lab results are shown below: Serum: Na+: 135 mEq/L Creatinine: 1.5 mg/dL Blood urea nitrogen: 37 mg/dL Urine: Na+: 13.5 mEq/L Creatinine: 18 mg/dL Osmolality: 580 mOsm/kg Which of the following is the most likely cause of this patient's increased creatinine level?

usmle-12191

A 14-year-old girl is brought to the clinic by her mom for an annual well-exam. The patient is concerned about her repeated ankle sprains and reports that “it has been harder to keep up in gym class.” Her mom reports that she has sprained her right ankle 4 times over the past year. The patient has otherwise been healthy with a normal birth history. Her father suffers from a “nerve disorder where his muscles shrink.” The patient denies any other concerns, pain, weight changes, fever, palpitations, or shortness of breath. Her menses are regular and without pain. A physical examination is unremarkable except for findings shown in Figure A. What is the most likely explanation for this patient’s symptoms?

usmle-12192

A 69-year-old woman is admitted to the hospital with substernal, crushing chest pain. She is emergently moved to the cardiac catheterization lab where she undergoes cardiac angiography. Angiography reveals that the diameter of her left anterior descending artery (LAD) is 50% of normal. If her blood pressure, LAD length, and blood viscosity have not changed, which of the following represents the most likely change in LAD flow from baseline?

usmle-12193

An academic medical center in the United States is approached by a pharmaceutical company to run a small clinical trial to test the effectiveness of its new drug, compound X. The company wants to know if the measured hemoglobin a1c (Hba1c) of patients with type 2 diabetes receiving metformin and compound X would be lower than that of control subjects receiving only metformin. After a year of study and data analysis, researchers conclude that the control and treatment groups did not differ significantly in their Hba1c levels. However, parallel clinical trials in several other countries found that compound X led to a significant decrease in Hba1c. Interested in the discrepancy between these findings, the company funded a larger study in the United States, which confirmed that compound X decreased Hba1c levels. After compound X was approved by the FDA, and after several years of use in the general population, outcomes data confirmed that it effectively lowered Hba1c levels and increased overall survival. What term best describes the discrepant findings in the initial clinical trial run by institution A?

usmle-12194

A 37-year-old female presents to her primary care provider for a normal follow-up visit. Her past medical history is notable for poorly controlled type II diabetes mellitus despite good treatment adherence to oral medications. She has been trialed on metformin and glyburide but stopped them due to rapid weight gain, respectively. She was started on a new oral diabetes medication three months ago. Since starting the new medication, she has noticed slowly progressive swelling in her lower extremities. Her temperature is 99.2°F (37.3°C), blood pressure is 120/75 mmHg, pulse is 105/min, and respirations are 22/min. She has gained 10 pounds since her last visit. Physical examination reveals 1+ pitting edema in the bilateral legs. A hemoglobin A1c lab test is drawn. This patient’s symptoms are most likely attributable to which of the following medications?

usmle-12195

A 44-year-old female with a 3-year history of biliary colic presents with acute cholecystitis. After further evaluation, she undergoes a laparoscopic cholecystectomy without complication. Which of the following is true following this procedure?

usmle-12196

A 29-year-old man has been admitted to the inpatient psychiatric ward after a suicide attempt. He has a history of schizophrenia for which he has been treated with multiple drugs. A new drug is started, and he receives an EKG which is shown in Figure A. A day later, the nurse's aide walks into the patient's room and witnesses him collapse. She initiates CPR and the code team rushes in to find him in the following rhythm (Figure B). Which of the following drugs was the most likely the cause of this episode?

usmle-12197

A 72-year-old woman with a history of atrial fibrillation on warfarin, diabetes, seizure disorder and recent MRSA infection is admitted to the hospital. She subsequently begins therapy with another drug and is found to have a supratherapeutic International Normalized Ratio (INR). Which of the following drugs is likely contributing to this patient's elevated INR?

usmle-12198

A 12-year-old boy presents to the emergency department with severe abdominal pain and nausea. He first began to have diffuse abdominal pain 15 hours prior to presentation. Since then, the pain has moved to the right lower quadrant. On physical exam he has tenderness to light palpation with rebound tenderness. Lifting his right leg causes severe right lower quadrant pain. Which of the following nerves roots was most likely responsible for the initial diffuse pain felt by this patient?

usmle-12199

A 43-year-old male is transferred from an outside hospital to the neurologic intensive care unit for management of a traumatic brain injury after suffering a 30-foot fall from a roof-top. He now lacks decision-making capacity but does not fulfill the criteria for brain-death. The patient does not have a living will and did not name a specific surrogate decision-maker or durable power of attorney. Which of the following would be the most appropriate person to name as a surrogate decision maker for this patient?

usmle-12200

A 62-year-old woman presents to her primary care physician for her annual checkup and says that she has been feeling fatigued recently. She can't think of any particular trigger for her symptoms and attributes it to getting older. She is also excited that she has been losing weight but denies changing her diet or exercise habits. She also says that she has been having some discomfort in her right breast but has otherwise been well. She drinks socially and has smoked one pack per day for the last 40 years. Physical exam reveals the finding shown in Figure A. Based on these clinical findings a biopsy is obtained and examined for histology. Which of the following findings would most likely be seen in this patient?

usmle-12201

A 45-year-old male presents to his primary care doctor complaining of abdominal pain. He reports a three-month history of intermittent burning pain localized to the epigastrium that worsens 2-3 hours after a meal. He attributes this pain to increased stress at his job. He is otherwise healthy and takes no medications. He does not smoke or drink alcohol. His temperature is 98.8°F (37.1°C), blood pressure is 130/85 mmHg, pulse is 90/min, and respirations are 18/min. Physical examination reveals mild epigastric tenderness to palpation. A urease breath test is positive. Which of the following treatments is most appropriate first-line therapy for this patient?

usmle-12202

A 65-year-old female presents to her primary care physician for a routine check-up. She reports feeling well but has noticed occasional weakness and constipation over the past few months. A complete blood count is within normal limits. Serum calcium is 11.9 mg/dL and serum phosphate is 2.4 mg/dL. Urine calcium output is 400 mg/24 h. A sestamibi scan demonstrates increased uptake near the inferior left pole of the thyroid gland. Which of the following mechanisms is most likely involved in this patient’s symptoms?

usmle-12203

A 58-year-old man presents to the emergency department with worsening shortness of breath, cough, and fatigue. He reports that his shortness of breath was worst at night, requiring him to sit on a chair in order to get some sleep. Medical history is significant for hypertension, hypercholesterolemia, and coronary heart disease. His temperature is 98.8°F (37.1°C), blood pressure is 146/94 mmHg, pulse is 102/min, respirations are 20/min with an oxygen saturation of 89%. On physical examination, the patient's breathing is labored. Pulmonary auscultation reveals crackles and wheezes, and cardiac auscultation reveals an S3 heart sound. After appropriate imaging and labs, the patient receives a non-rebreather facemask, and two intravenous catheters. Drug therapy is initiated. Which of the following is the site of action of the prescribed drug used to relieve this patient's symptoms?

usmle-12204

A 4-year-old male is brought to the office by his mother with a 4-day history of nose bleeds and bleeding gums. The patient has no past medical history and does not take medications. He denies any similar past episodes, as well as oliguria, bloody stools, headache, or diarrhea. His vitals signs are as follows: 37C, BP92/60, HR82, RR18. The patient is fully alert and oriented. Physical examination is notable for diffuse petechial rash on the bilateral lower extremities. Complete blood count reveals a platelet count of 20,000 per mm^3. A bone marrow aspiration smear is seen in Figure A and the pathologist notes an increased number of the large cells in other fields. Which of the following is the most likely mechanism underlying the patient's illness?

usmle-12205

An 82-year-old man is brought in by his son after the patient began to slur his speech and became unsteady with his footing. The patient was driven in from his rural home, and arrived to the emergency department three hours after onset of symptoms. The patient's past medical history is notable for hypertension, diabetes, and peptic ulcer disease. Upon arrival, vital signs are stable; a non-contrast CT of the head is shown in Figure A. The patient is begun on IV tissue-plasminogen activator (tPA). Seven minutes after initiation of treatment, the patient becomes hypotensive and tachycardic. Shortly after he begins to vomit copious amounts of blood. Which of the following is the best treatment for this patient?

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A 42-year-old man presents to his primary care provider complaining of insomnia. He describes 3 months of frequent nighttime awakenings and nightmares. Per chart review, he is a combat veteran and was on a military tour in Afghanistan 4 months ago when a car bomb exploded, injuring him and killing his friend; however, when the physician asks about this, the patient states that he “does not talk about that” and changes the subject. He reports anxiety, irritability and feeling detached from his friends and family, which he believes is harming his relationships. Physical exam reveals an overweight, anxious appearing man with normal vital signs and an exaggerated startle response. Which of the following medications might have helped prevent this patient’s current disorder?

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A 69-year-old woman comes to the clinic for an annual well exam. She reports no significant changes to her health except for an arm fracture 3 weeks ago while she was lifting some heavy bags. Her diabetes is well controlled with metformin. She reports some vaginal dryness that she manages with adequate lubrication. She denies any weight changes, fevers, chills, palpitations, nausea/vomiting, incontinence, or bowel changes. A dual-energy X-ray absorptiometry (DEXA) scan was done and demonstrated a T-score of -2.7. She was subsequently prescribed a selective estrogen receptor modulator, in addition to vitamin and weight-bearing exercises, for the management of her symptoms. What is the mechanism of action of the prescribed medication?

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A newborn infant is born at 42 weeks gestation to a healthy 36-year-old G1P0. The delivery was complicated by prolonged labor and shoulder dystocia. The child is in the 87th and 91st percentiles for height and weight at birth, respectively. The mother’s past medical history is notable for diabetes mellitus and obesity. Immediately after birth, the child’s temperature is 99°F (37.2°C), blood pressure is 90/50 mmHg, pulse is 120/min, and respirations are 24/min. The child demonstrates a strong cry and pink upper and lower extremities bilaterally. The right arm is adducted and internally rotated at the shoulder and extended at the elbow. Flexion and extension of the wrist and digits appear to be intact in the right upper extremity. Which of the following muscles would most likely have normal strength in this patient?

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A 16-year-old boy is brought to the emergency department after being tackled at a football game. Per his mom, he is the quarterback of his team and was head-butted in the left shoulder region by the opposing team. Shortly after, the mother noticed that his left arm was hanging by his torso and his hand was “bent backwards and facing the sky.” The patient denies head trauma, loss of consciousness, sensory changes, or gross bleeding. A physical examination demonstrates weakness in abduction, lateral rotation, flexion, and supination of the left arm and tenderness of the left shoulder region with moderate bruising. Radiograph of the left shoulder and arm is unremarkable. Which of the following is most likely damaged in this patient?

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A 41-year-old woman presents to her primary care provider with a skin lesion on the back of her neck. The lesion is not itchy or painful. She believes the lesion is new. Her past medical history is notable for generalized anxiety disorder for which she takes fluoxetine. She has had occasional diarrhea, increased flatulence, and worsening fatigue over the past 2 years. She has a 10 pack-year smoking history and drinks 3-4 glasses of wine per day. Her temperature is 99°F (37.2°C), blood pressure is 130/75 mmHg, pulse is 90/min, and respirations are 18/min. Her BMI is 21 kg/m^2. A notable skin finding is shown in Figure A. An immunohistochemical analysis of this lesion would most likely reveal elevated levels of which of the following?

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A 32-year-old man presents to the emergency department with fever, weight loss, and right upper quadrant pain. He says that he started experiencing nausea and fatigue after he returned from a honeymoon trip to Asia with his wife. Notably, she is 5 months pregnant with their first child. On presentation, his temperature is 100.8°F (38.2°C), blood pressure is 118/79 mmHg, pulse is 81/min, and respirations are 14/min. Physical exam reveals a jaundiced patient with a palpable liver edge as well as splenomegaly. Labs are sent in order to confirm the diagnosis. After confirmation, the patient's wife is immediately tested as well because she is at a much higher risk of fatal complications from this infection. The organism that is most likely responsible for this patient's symptoms has which of the following structures?

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A 40-year-old Indian female is hospitalized with exertional dyspnea and lower extremity edema. The patient immigrated to the United States at age 15 and does not use tobacco, alcohol, or drugs. A mid-diastolic murmur is present and heard best at the apex. Which of the following symptoms would be most consistent with the rest of the patient’s presentation?

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A 71-year-old man is brought to the emergency department by his daughter after she found him to be extremely confused at home. She says that he appeared to be fine in the morning; however, upon returning home, she found that he was slumped in his chair and was hard to arouse. She was worried that he may have taken too many medications and rushed him to the emergency department. His past medical history is significant for bipolar disorder and absence seizures. He does not smoke and drinks 4 alcoholic beverages per night on average. On physical exam, he is found to have a flapping tremor of his hands, pitting ankle edema, and gynecomastia. He does not appear to have any focal neurologic deficits. Which of the following lab findings would most likely be seen in this patient?

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A 57-year-old HIV-positive male with a history of intravenous drug abuse presents to the emergency room complaining of arm swelling. He reports that he developed progressively worsening swelling and tenderness over the right antecubital fossa three days prior. He recently returned from a trip to Nicaragua. His past medical history is notable for an anaphylactoid reaction to vancomycin. His temperature is 101.4°F (38.6°C), blood pressure is 140/70 mmHg, pulse is 110/min, and respirations are 20/min. Physical examination reveals an erythematous, fluctuant, and tender mass overlying the right antecubital fossa. Multiple injection marks are noted across both upper extremities. He undergoes incision and drainage and is started on an antibiotic that targets the 50S ribosome. He is discharged with plans to follow up in one week. However, five days later he presents to the same emergency room complaining of abdominal cramps and watery diarrhea. Which of the following classes of pathogens is most likely responsible for this patient’s current symptoms?

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A 43-year-old homeless man is brought to the emergency room for severe abdominal pain. He is known to the emergency department for repeated visits for alcohol intoxication. He reports that the pain started about 3 hours ago and describes it as sharp, piercing, 10/10, and concentrated at the epigastric region with radiation to the back. His past medical history is unclear given his homeless status. His temperature is 100.4°F (38°C), blood pressure is 104/80 mmHg, the pulse is 104/min, and respirations are 16/min. A physical examination demonstrates epigastric tenderness and the finding shown in Figure A. What is the most likely diagnosis for this patient?

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A 29-year-old man presents to his primary care provider complaining of testicular pain. He reports a four-day history of dull chronic pain in his left testicle that is worse with standing. His past medical history is notable for asthma and major depressive disorder. He takes inhaled albuterol as needed and sertraline. He is sexually active with a single female partner and always uses barrier protection. His temperature is 99.2°F (37.3°C), blood pressure is 125/75 mmHg, pulse is 85/min, and respirations are 17/min. Physical examination reveals a non-tender twisted mass along the left spermatic cord that disappears when the patient lies supine. This patient’s condition most likely stems from decreased laminar flow at which of the following vascular junctions?

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A 60-year-old male presents to the emergency room complaining of substernal chest pain. He reports a three-hour history of dull substernal chest pain that radiates into his left arm and jaw. He had a similar incident two months ago after walking one mile, but this pain is more severe. His past medical history is notable for hypertension and hyperlipidemia. An EKG demonstrates non-specific changes. Serum troponins are normal. In addition to aspirin, oxygen, and morphine, he is started on a medication that generates endothelial nitric oxide. Which of the following is a downstream effect of this molecule?

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A 73-year-old woman presents to clinic with a week of fatigue, headache, and swelling of her ankles bilaterally. She reports that she can no longer go on her daily walk around her neighborhood without stopping frequently to catch her breath. At night she gets short of breath and has found that she can only sleep well in her recliner. Her past medical history is significant for hypertension and a myocardial infarction three years ago for which she had a stent placed. She is currently on hydrochlorothiazide, aspirin, and clopidogrel. She smoked 1 pack per day for 30 years before quitting 10 years ago and socially drinks around 1 drink per month. She denies any illicit drug use. Her temperature is 99.0°F (37.2°C), pulse is 115/min, respirations are 18/min, and blood pressure is 108/78 mmHg. On physical exam there is marked elevations of her neck veins, bilateral pitting edema in the lower extremities, and a 3/6 holosystolic ejection murmur over the right sternal border. Echocardiography shows the following findings: End systolic volume (ESV): 100 mL End diastolic volume (EDV): 160 mL How would cardiac output be determined in this patient?

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A 64-year-old man presents to his primary care physician because of a tremor that he has developed over the last several months. He says that the tremor is worst when he is resting but becomes better when he engages in movements such as picking up the remote for his TV. His wife also says that his movements have become slower over the last few months. Physical exam reveals increased resistance to passive motion of his extremities. Gait exam also shows trouble with starting movement and short, shuffling steps. The most likely cause of this patient's symptoms involve the degeneration of a certain subset of neurons. When the substance released by these neurons interact with a G-alpha-s coupled receptor, which of the following effects occurs?

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A 33-year-old man is brought to a psychiatric emergency room in St. Louis by policemen who report that they found him loitering at the main bus station. The patient is unable to recall why he was at the bus station, but he does have a bus ticket in his pocket from Chicago to St. Louis. When asked what his name is, he replies “I don’t know.” He has no source of identification and cannot recall his own past medical history or medications. His temperature is 98.8°F (37.1°C), blood pressure is 130/75 mmHg, pulse is 85/min, and respirations are 20/min. On examination, the patient is alert but is not oriented to person, place, or time. He appears anxious and upset but is appropriately conversant and cooperative with the examination. His pupils are equally round and reactive to light. The rest of the examination is normal. A urine toxicology screen is negative. A family member of the patient contacts the hospital the next morning and reports that the patient is a soldier who recently returned from a deployment in Afghanistan. He was last seen at his home in Chicago. Which of the following is most consistent with this patient’s condition?

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A 52-year-old man presents to his primary care physician complaining of a blistering rash in his inguinal region. Upon further questioning, he also endorses an unintended weight loss, diarrhea, polydipsia, and polyuria. A fingerstick glucose test shows elevated glucose even though this patient has no previous history of diabetes. After referral to an endocrinologist, the patient is found to have elevated serum glucagon and is diagnosed with glucagonoma. Which of the following is a function of glucagon?

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A 22-year-old female smoker undergoes laboratory testing. Which of the following findings would be implicated in the pathogenesis of the flow-volume loop (red lines; normal is blue line) shown in Figure A?

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A 32-year-old man with Crohn disease is brought to the emergency department after he fainted at work. He says that he has been feeling increasingly fatigued and weak over the last several weeks though he has not previously had any episodes of syncope. On presentation he is found to be pale and agitated. A panel of lab tests is performed showing the following: Hemoglobin: 10.2 g/dL Hematocrit: 30.1% Leukocyte count: 9,900 cells/mm^3 with normal differential Platelet count: 290,000/mm^3 Mean corpuscular volume: 118 µm^3 Elevated homocysteine level Normal methylmalonic acid level Which of the following mechanisms explains how Crohn disease may have contributed to this patient's symptoms?

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A 65-year-old female with metastatic breast cancer presents to the emergency room complaining of severe right hip pain. She is accompanied by her husband who reports that she fell while walking down the stairs. Her right leg is shortened and internally rotated. A radiograph reveals a severely comminuted intertrochanteric femoral neck fracture. She is brought to the operating room where she undergoes a right hip arthroplasty. On post-operative day #3, she develops a fever, chills, lower abdominal pain, dysuria, and frequent urination. Her temperature is 101.1°F (38.4°C), blood pressure is 90/60 mmHg, pulse is 115/min, and respirations are 20/min. Her incision appears clean, dry, and intact. Her lungs are clear to auscultation bilaterally. She is tender to palpation in the right and left lower abdominal quadrants. A Foley catheter is placed. Results from a urine culture on an agar plate are shown in Figure A. Which of the following organisms is most likely responsible for this patient’s current symptoms?

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A 32-year-old woman presents to the emergency department because she has a cord-like rash on her left calf that is red and painful to touch. She says that she has had multiple such lesions previously. Other medical history reveals that she has had 3 past spontaneous abortions at < 10 weeks of gestational age but has never been diagnosed with any diseases. She drinks socially but has never smoked or used drugs. She has never taken any medications except for over the counter analgesics and antipyretics. Physical exam shows that the cord-like lesion is tender, thick, and hardened on palpation. In addition, she has a lacy mottled violaceous rash on multiple extremities. Which of the following antibodies would most likely be found in this patient's blood?

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A 58-year-old man undergoes coronary angiography that demonstrates a 90% stenosis of the left anterior descending coronary artery. The circumflex branch of the left coronary artery is not significantly obstructed. Prior to the angiogram, he underwent a pharmacologic cardiac stress test. When administered, the pharmacologic agent caused the left circumflex artery to vasodilate, with resulting increased blood supply to its supplied myocardium that was already well-perfused at baseline. This increased flow through the circumflex artery shunted blood flow away from the myocardium supplied by the stenosed left anterior descending artery, resulting in ischemia that manifested as a perfusion defect on radionuclide imaging. Which of the following agents is most strongly associated with this phenomenon described above?

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A 6-year-old girl presents with bowed legs and loose joints. Examination of her chest is shown in Figure A. Her growth chart shows she is falling further behind in growth and is currently at the 45th percentile. Laboratory results reveal a low serum phosphorous, an elevated alkaline phosphatase and low serum calcium. Which of the following would you expect to see histologically?

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A 43-year-old man returns to the United States after visiting his relatives in Ghana and presents to the primary care clinic after experiencing a week of high fevers, chills, and sweats that have receded and returned. On physical examination, the patient is found to have pale conjunctiva and an enlarged spleen. The physician obtains a peripheral blood smear that shows the following (Figure A). Which of the following is the causative organism resulting in this patient's presentation?

usmle-12229

A 69-year-old male with a history of metastatic small cell lung carcinoma on chemotherapy presents to his oncologist for a follow-up visit. He has responded well to etoposide and cisplatin with plans to undergo radiation therapy. However, he reports that he recently developed multiple “spots” all over his body. He denies any overt bleeding from his gums or joint swelling. His past medical history is notable for iron deficiency anemia, osteoarthritis, and paraneoplastic Lambert-Eaton syndrome. He has a 40 pack-year smoking history. His temperature is 98.5°F (36.9°C), blood pressure is 130/70 mmHg, pulse is 115/min, and respirations are 20/min. On examination, a rash is noted diffusely across the patient’s trunk and bilateral upper and lower extremities. Results from a complete blood count are shown below: Hemoglobin: 11.9 mg/dl Hematocrit: 35% Leukocyte count: 5,000/mm^3 Platelet count: 20,000/mm^3 The oncologist would like to continue chemotherapy but is concerned that the above results will limit the optimal dose and frequency of the regimen. A recombinant version of which of the following is most appropriate in this patient?

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A 67-year-old woman with a recently found hepatic carcinoma has been an inpatient for more than a week. During morning rounds, she was abnormally disoriented to time and place along with a shortened attention span. The overnight resident reports that she was coming in and out of this state for the past couple nights. The patient was known to drink often, but reported that she has not consumed alcohol in weeks leading up to her admission. She is not jaundiced and has no metabolic imbalance upon laboratory tests. What is the most likely cause of her recent mental impairment?

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A 22-year old active duty soldier presents to your clinic with complaints of intense fatigue, fevers, abdominal pain, and a nonproductive cough. Her symptoms began a few days ago, but she returned from a tour of duty in Malawi and Mozambique four weeks ago. She endorses sleeping outside, using minimal bug spray, and swimming in rivers during her tour. On physical exam, her temperature is 101.5, and she appears exhausted. She has a hive-like rash scattered over her body. Her abdominal exam is notable for hepatosplenomegaly, and her lung exam is notable for scattered crackles. Her CBC with diff is remarkable for marked eosinophilia, and she has an elevated IgE. Of the following organisms, infection with which one is most consistent with her symptoms?

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A 58-year-old man comes to the clinic complaining of increased urinary frequency for the past 3 days. The patient reports that he has had to get up every few hours in the night to go to the bathroom, and says "whenever I feel the urge I have to go right away.” Past medical history is significant for a chlamydial infection in his twenties that was adequately treated. He endorses lower back pain and subjective warmth for the past 2 days. A rectal examination reveals a slightly enlarged prostate that is tender to palpation. What is the most likely explanation for this patient’s symptoms?

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An 11-year-old boy arriving in the US with his family from Syria is brought to the emergency department after several days of fever, chills, and a sore throat. His temperature is 39°C (102.2°F), pulse is 80/min, respirations are 16/min, and blood pressure is 110/84 mmHg. Physical exam reveals a swollen, tender neck and the finding shown in Figure A. His parents report that he has had no vaccinations. Given this presentation, the patient is treated with an antibiotic as well as an antitoxin to prevent cardiac or nervous system damage. The most likely causative organism in this case produces a toxin that affects which of the following cellular processes?

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A 56-year-old female presents for initial evaluation by a rheumatologist with a chief complaint of back and joint pain. She says that she has been having mild pain for years, but that the pain has become worse over the course of the last 6 months. She clarifies that the pain is most severe in the mornings just after waking up but seems to improve throughout the day. She also notices that her mouth feels dry and she has difficulty eating dry food such as crackers. Finally, she has the sensation of having bits of sand in her eyes. She denies any past medical history or medication use. Serology for which of the following would most likely be positive in this patient?

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A 31-year-old female presents to the emergency room complaining of fever and difficulty breathing. She first noticed these symptoms 3 days prior to presentation. Her past medical history is notable for well-controlled asthma. She does not smoke and drinks alcohol socially. Upon further questioning, she reports that her urine is tea-colored when she wakes up but generally becomes more yellow and clear over the course of the day. Her temperature is 100.8°F (38.2°C), blood pressure is 135/90 mmHg, pulse is 115/min, and respirations are 20/min. Lung auscultation reveals rales at the right lung base. Laboratory analysis is shown below: Hemoglobin: 9.4 g/dL Hematocrit: 31% Leukocyte count: 3,700 cells/mm^3 with normal differential Platelet count: 110,000/mm^3 Reticulocyte count: 3% A chest radiograph reveals consolidation in the right lung base and the patient is given oral antibiotics. Which of the following processes is likely impaired in this patient?

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A 19-year-old college student is brought to the emergency department by his roommates after being found unconscious on their dorm room floor. His temperature is 102.0°F (38.9°C) and blood pressure is 85/64 mmHg. On physical examination, he has multiple rose-colored spots on the skin covering his abdomen and lower limbs. Lab tests reveal hyperkalemia and an arterial blood gas test that reads pH: 7.04, pCO2: 30.1 mmHg, pO2: 23.4 mmHg. What is the most likely diagnosis for this patient’s condition?

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A 41-year-old man presents to the emergency department with a 6-hour history of muscle cramping, decreased appetite, and diarrhea. He says that these symptoms came on rapidly but does not recall anything that may have triggered the episode. He has never experienced these symptoms before. His past medical history is significant for obesity, sleep apnea, and type 2 diabetes that is well controlled on metformin. He also has gastroesophageal reflux disease for which he occasionally takes antacids. On presentation he is found to have fast, shallow breathing and abdominal pain that is poorly localized. Basic labs as well as an arterial blood gas are obtained and the results are shown below: Na+: 139 mEq/L Cl-: 106 mEq/L HCO3-: 11 mEq/L pH: 7.25 pCO2: 22 mmHg Which of the following is the most likely cause of the changes seen in this patient's labs?

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A 61-year old obese nulliparous female presents to your office with right lower quadrant abdominal pain. Her medical history is significant for breast cancer and past use of postmenopausal estrogen replacement therapy. This patient most likely has elevated levels of which of the following?

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A 24-year-old female medical student presents to the emergency department after she develops sudden difficulty breathing and vague chest pain while preparing for exams. The chest pain is non-pleuritic without radiation. She denies any recent travel. She denies any hemoptysis, nausea, vomiting, or leg pain. She only takes oral contraceptives; she denies smoking or alcohol use. Her vitals reveal a heart rate of 120 beats per minute, blood pressure of 100/80 mm Hg, and respiratory rate of 30 per minute. She is afebrile. Otherwise, her physical exam is unremarkable. A CT scan of her chest with IV contrast reveals filling defects along her left pulmonary artery. Which of the following is the most likely mechanism of this finding?

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A 54-year-old man presents to his primary care physician with a 2-week history of increasing fatigue and shortness of breath. He says that he has also noticed some swelling in his legs as well as changes in his urine, which now appears frothy. Physical exam is significant for periorbital and lower extremity edema. Laboratory testing is significant for hypoalbuminemia and urinalysis demonstrates 4+ protein. Given these findings, a kidney biopsy is obtained and histology is shown in Figure A. Which of the following treatments would most likely be effective for this patient?

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A 51-year-old Caucasian female presents to her primary care provider complaining of intermittent chest pain. She reports that over the past 6 months, she has developed burning chest pain that occurs whenever she exerts herself. The pain decreases when she rests. Her past medical history is notable for type II diabetes mellitus. Her family history is notable for multiple myocardial infarctions in her father and paternal grandmother. She currently takes aspirin and metformin. Her primary care provider starts her on a medication which is indicated given her medical history and current symptoms. However, 10 days later, she presents to the emergency room complaining of weakness and muscle pain. Her plasma creatine kinase level is 250,000 IU/L. This patient was most likely started on a medication that inhibits an enzyme that produces which of the following?

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A 47-year-old man was brought in by his wife for progressively worsening memory and bizarre behavior over the past 2 months. The wife reports that he has been sleeping 15 hours a day, but is still complaining of fatigue. He frequently forgets important events such as his son’s graduation and left the stove running 2 days ago. During the encounter, the patient reports that “it is no longer worth living.” Past medical history is significant for a corneal transplant 7 years ago. Physical examination reveals depressed mood, healed surgical scar on the left neck, and sustained jerking of the left foot. Which of the following could have prevented this patient’s condition?

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A 3-year-old male is brought by his mother to the pediatrician's office. The mother and child are refugees from Somalia and arrived in the United States one week ago. They were recently placed in temporary housing. The mother reports that the child has been chronically tired and subdued since before their arrival in the United States. The child was born at 38 weeks gestation with the help of a local midwife. The child’s temperature is 98.2°F (36.8°C), blood pressure is 105/60 mmHg, pulse is 90/min, and respirations are 18/min. Physical examination reveals a listless child with a rotund abdomen and positive fluid wave. Notable lower extremity edema is present. This patient's condition is most likely caused by a deficiency in which of the following?

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A 29-year-old G1P0 woman at 32 weeks of gestation comes to the emergency department complaining of vaginal bleeding for the past hour. She noticed some blood on the toilet paper when she went to the bathroom an hour ago, but now she is bleeding through her underwear. She denies any trauma, pain, abnormal discharge or odor, fever, or recent infections. The patient mentioned that that during her last ultrasound, the doctor told her that, “there’s an abnormality but not to worry,” but she can’t remember the name of the condition. Her temperature is 100.1°F (37.8°C), blood pressure is 120/70 mmHg, pulse is 86/min, and respirations are 15/min . A fetal heart tracing is obtained and shows a fetal heart rate of 130-140, long-term variability, and appropriate accelerations. What is the most likely explanation for this patient’s presentation?

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A 35-year-old woman with no significant past medical history is brought in by ambulance after a major motor vehicle collision. Temperature is 97.8 deg F (36.5 deg C), blood pressure is 76/40, pulse is 110/min, and respirations are 12/min. She arouses to painful stimuli and makes incomprehensible sounds, but is unable to answer questions. Her abdomen is distended and diffusely tender to palpation. Bedside ultrasound shows blood in the peritoneal cavity. Her husband rushes to the bedside and states she is a Jehovah’s Witness and will refuse blood products. No documentation of blood refusal is available for the patient. What is the most appropriate next step in management?

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A 54-year-old man comes to the emergency department for nausea and vomiting for the past 2 days. The patient reports that he felt tired and weak for the past week without any obvious precipitating factors. Past medical history is significant for hypertension controlled with hydrochlorothiazide. He denies diarrhea, changes in diet, recent surgery, vision changes, or skin pigmentation but endorses a 10-lb weight loss, headaches, fatigue, and a chronic cough for 2 years. He smokes 2 packs per day for the past 20 years but denies alcohol use. Physical examination demonstrates generalized weakness with no peripheral edema. Laboratory tests are shown below: Serum: Na+: 120 mEq/L Cl-: 97 mEq/L K+: 3.4 mEq/L HCO3-: 24 mEq/L Ca2+: 10 mg/dL Osmolality: 260 mOsm/L Urine: Na+: 25 mEq/L Osmolality: 285 mOsm/L Specific gravity: 1.007 What is the most likely finding in this patient?

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A 16-year-old female is brought to the primary care clinic by her mother. The mother is concerned about her daughter’s grades, which have been recently slipping. Per the mother, the patient usually earns a mix of As and Bs in her classes, but this past semester she has been getting Cs and a few Ds. Her mother is also frustrated because she feels like her daughter is acting out more and “hanging out with some no-good friends.” Upon questioning the patient with her mother in the room, the patient does not say much and makes no eye contact. The mother is asked to leave the room and the patient is questioned again about any stressors. After rapport is established, the patient breaks down and tearfully admits to trying various drugs in order to “fit in with her friends.” She says that she knows the drugs “are not good for me” but has been very stressed out about telling her friends she’s not interested. Detailed questioning reveals that the patient has been using alcohol, cocaine, and marijuana 2-3 times per week. The patient becomes agitated at the end of the interview and pleads for you to not tell her mother. She says that she knows they’re illegal but is very afraid of what her parents would say. What is the best action in response to the adolescent’s request?

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A 22-year-old man is brought to the emergency department after he was impaled by a metal rod during a work accident. The rod went into his back around the level of T9 but was removed before arrival. He has no past medical history and does not take any medications. On physical examination, he has significant muscle weakness in his entire left lower body. He also exhibits impaired vibration and proprioception in his left leg as well as loss of pain and temperature sensation in his right leg. Which of the following sections of the spinal cord was most likely damaged in this patient?

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A 67-year-old man with a past medical history of poorly-controlled type 2 diabetes mellitus (T2DM) is brought to the emergency department for acute onset nausea and vomiting. According to the patient, he suddenly experienced vertigo and began vomiting 3 hours ago while watching TV. He reports hiking in New Hampshire with his wife 2 days ago. Past medical history is significant for a myocardial infarction (MI) that was treated with cardiac stenting, T2DM, and hypertension. Medications include lisinopril, aspirin, atorvastatin, warfarin, and insulin. Physical examination demonstrates left-sided facial droop and decreased pinprick sensation at the right arm and leg. What is the most likely etiology of this patient’s symptoms?

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To protect against a potentially deadly infection, a 19-year-old female receives a vaccine containing capsular polysaccharide. This vaccine will stimulate her immune system to produce antibodies against which organism?