SeanWu25/NEJM-AI_Benchmarking_Medical_Language_Models huggingface dataset:
Subject: Disorders of Divalent Ions, Renal Bone Disease and Nephrolithiasis

A 74-year-old woman has been receiving hemodialysis for 4 years. She has a history of severe peripheral vascular disease, coronary artery disease, renal artery stenosis, and chronic atrial ﬁbrillation. She describes having aches and pains in the hips, legs, shoulders, and lower back. She has taking paricalcitol 2 µg with each dialysis session and takes calcium acetate 1334 mg with each meal. Her PTH values have ranged from 312 to 479 pg/ml (reference range 12–72 pg/ml) over the past 12 months. Her serum calcium values have ranged from 9.8 to 10.1 mg/dl, serum phosphorus values have ranged from 4.7 to 5.4mg/dl, and alkaline phosphatase values have ranged between 389 and 492 U/ml (reference range 36–92 U/ml). The serum gamma glutamyl transpeptidase and bilirubin are normal. The 25-hydroxyvitamin D level is 32 ng/ml (reference range 20–80 ng/ml). Her primary doctor had obtained a dual-energy x-ray absorptiometry (DEXA) scan, which showed a T score of -2.9 at the hip and -2.5 at the lumbar spine..
Question: Which ONE of the following is the MOST appropriate management?
1. Increase paricalcitol
2. Increase calcium acetate
3. Calcifediol 30 µg daily
4. Add cinacalcet
Answer: D
Subject: Disorders of Divalent Ions, Renal Bone Disease and Nephrolithiasis

A 65-year-old man with ESRD who has been receiving maintenance hemodialysis for 2 months is evaluated during weekly dialysis rounds. Laboratory values are calcium 10.4 mg/dl, phosphorus 6.5 mg/dl, PTH 745 pg/ml (reference range 12–72 pg/ml), and alkaline phosphatase 212 U/ml (reference range 36–92 U/ml). He has been taking calcium acetate 2001 mg with each meal..
Question: Which ONE of the following statements regarding cinacalcet is CORRECT?
1. Addition of cinacalcet is appropriate based on this patient’s laboratory ﬁndings
2. Cinacalcet therapy is not associated with a reduction of serum phosphorus
3. Cinacalcet is associated with decreased cardiovascular and all-cause mortality
4. The addition of cinacalcet will likely lead to increased vascular calciﬁcation
5. Cinacalcet therapy will decrease PTH levels by 15% to 20%
Answer: A
Subject: Disorders of Divalent Ions, Renal Bone Disease and Nephrolithiasis

Both calcimimetic therapy and parathyroidectomy can effectively control secondary hyperparathyroidism in patients with ESRD..
Question: Which ONE of the following statements is CORRECT?
1. Cinacalcet and parathyroidectomy are as-sociated with a similar decrease in serum calcium
2. The effect of increasing bone mineral density with calcimimetic therapy and parathyroidectomy are comparable
3. Both cinacalcet and parathyroidectomy de-crease levels of ﬁbroblast growth factor-23 (FGF23)
4. Etelcalcetide reduces serum PTH but does not affect levels of FGF23
Answer: C
Subject: Disorders of Divalent Ions, Renal Bone Disease and Nephrolithiasis

It has been demonstrated that levels of FGF23 increase early in the course of CKD and have been associated with an increase in mortality..
Question: Which ONE of the following is CORRECT?
1. FGF23 increases the production of inﬂammatory cytokines
2. FGF23 increases erythropoietin production
3. Erythropoietin therapy decreases the levels of FGF23 in circulation
4. Increased FGF23 levels are associated with decreased cardiac output
5. Iron deﬁciency decreases FGF23 production
Answer: A
Subject: Disorders of Divalent Ions, Renal Bone Disease and Nephrolithiasis

Your internal medicine colleague asks you about the evaluation and management of bone disease in an 80-year-old woman with advanced stage 4 CKD. Over the past 3 years, she has experienced worsening kyphoscoliosis and vertebral body collapse, with associated pain. Laboratory studies show a serum PTH level of 436 pg/ml (reference range 12–72 pg/ml), calcium level of 9.3 mg/dl, phosphorus of 4.9 mg/dl, alkaline phosphatase level of 156 U/ml (reference range 36–92 U/ml), and serum creatinine level of 2.9 mg/dl (eGFR 16 ml/min per 1.73 m2). A DEXA scan shows a T-score of -2.8 at the hip and -2.9 at the lumbar spine..
Question: Which ONE the following should you tell your colleague about the evaluation and management of bone disease in CKD stage G3a–G5D?
1. Measurements of DEXA are useful in predicting the underlying bone histologic features in patients with CKD stage G3a–G5D
2. DEXA is predictive of fracture risk in adults with CKD stage G3a–G5D
3. Parathyroidectomy has not been associated with increases in bone density
4. Denosumab may lead to hypercalcemia in patients with CKD
Answer: B
Subject: Disorders of Divalent Ions, Renal Bone Disease and Nephrolithiasis

A 43-year-old man received a deceased donor kidney transplant after 7 years of dialysis. Two months later, the serum creatinine is 1.4 mg/dl (stable), the serum calcium is 11.2 mg/dl, the phosphorus is 1.7 mg/dl, and the serum PTH is 246 pg/ml (reference range 12–72 pg/ml). A recent DEXA scan shows normal bone mineral density..
Question: Which ONE of the following statements is CORRECT?
1. He should be prescribed paricalcitol to decrease PTH
2. He has tertiary hyperparathyroidism and needs urgent parathyroidectomy
3. The majority of such patients are expected to achieve remission of hyperparathyroidism after 1 year of cinacalcet therapy
4. Cinacalcet therapy would be expected to lower serum phosphorus further
Answer: C
Subject: Disorders of Divalent Ions, Renal Bone Disease and Nephrolithiasis

A 27-year-old man is evaluated for hypocalcemia. He has been experiencing paresthesias for the past 6 months and recently had an episode in which he experienced a prolonged and painful cramp of his right hand. He has otherwise been in good health. A physical examination reveals that Chvostek and Trousseau signs are present. The serum electrolytes and creatinine are normal. The serum calcium is 6.7 mg/dl, the ionized calcium is 0.5 mmol/L (reference range 1.10 to 1.35 mmol/L), the serum magnesium is 2.0 mg/dl, and the serum phosphorus is 5.8 mg/dl..
Question: Which ONE of the following genetic abnormalities BEST explains this clinical condition?
1. A gain of function mutation in the calcium sensing receptor gene
2. A loss of function mutation in the calcium sensing receptor gene
3. A mutation in the adaptor-related protein complex 2 sigma subunit 1 (AP2S1) gene
4. Loss of function mutation in G-protein α- 11
Answer: A
Subject: Disorders of Divalent Ions, Renal Bone Disease and Nephrolithiasis

A 52-year-old African American woman with ESRD, hypertension, and diabetes mellitus has been treated with multiple daily insulin injections for the past 10 years and maintenance in-center hemodialysis for the past 4 years. The patient’s serum calcium and phosphate levels have been maintained with in the range suggested by the KDIGO 2017 Clinical Practice Guideline. PTH levels have ranged between 486 and 592 pg/ml (reference range 12–72 pg/ml). She had been treated with activated vitamin D in an attempt to control her hyperparathyroidism..
Question: In assessing this patient’s risk for calciﬁc uremic arteriolopathy, which ONE of the following factors is MOST likely associated with an increased risk of the complication?
1. Hypertension
2. Her ethnicity
3. Her use of activated vitamin D
4. Her treatment with multiple insulin injections
Answer: D
Subject: Disorders of Divalent Ions, Renal Bone Disease and Nephrolithiasis

A 64-year-old woman with a 15-year history of essential hypertension successfully managed with hydrochlorothiazide therapy is evaluated during a routine follow-up visit and is found to have hypercalcemia. Her physical examination is unremarkable. She describes having increased difﬁculty sleeping, and she notes persistent constipation. A colonoscopy performed last year was unremarkable. Laboratory values show serum sodium of 145 mEq/L, potassium of 4.6 mEq/L, chloride of 105 mEq/L, total CO2 of 25 mmol/L, BUN of 22 mg/dl, creatinine of 1.4 mg/dl, calcium of 11.4, and phosphorus of 2.1 mg/dl. The 24-hour urine calcium excretion is 262 mg. The results of radiologic studies including chest radiograph and abdominal computed tomography (CT) are normal..
Question: Which ONE of the following is the MOST likely primary cause of her hypercalcemia?
1. Primary hyperparathyroidism
2. Familial hypocalciuric hypercalcemia
3. Thiazide-induced hypocalciuria
4. Occult malignancy
5. Sarcoidosis
Answer: A
Subject: Disorders of Divalent Ions, Renal Bone Disease and Nephrolithiasis

A 67-year-old man with recent onset of ESRD resulting from diabetic kidney disease is evaluated 1 week after starting hemodialysis. He is asymptomatic and is up to date on all age-appropriate cancer screenings. Routine laboratory studies show a hemoglobin of 11.1 gm/dl, albumin of 3.5 g/dl, creatinine of 6.7 mg/dl, calcium of 9.8 mg/dl, phosphorus of 3.7 mg/dl, and PTH of 363 pg/ml (reference range 12–72 pg/ml)..
Question: At this point, which ONE of the following would you recommend next?
1. Begin calcitriol
2. Begin cinacalcet therapy
3. Begin phosphate binder therapy
4. Measure ionized calcium
5. Measure PTH-related protein
Answer: D
Subject: Disorders of Divalent Ions, Renal Bone Disease and Nephrolithiasis

A 61-year-old man is referred for evaluation of hypercalcemia. He has had 2 months of progressive weakness, bone pain, nausea, and anorexia. Over the past 3 weeks, he has experienced intense thirst and polyuria associated with weight loss of 8 kg. Laboratory studies showed a serum calcium of 12.2 mg/dl and a serum PTH of 12 pg/ml (reference range 12-72 pg/ml). The serum sodium was 144 mEq/L, potassium was 3.6 mEq/L, chloride was 96 mEq/L, total CO2 was 30 mmol/L, BUN was 35 mg/dl, creatinine was 1.6 mg/dl (increased from 0.9 mg/dl 1 month ago), and glucose was 78 mg/dl. The patient denied use of oral vitamin D supplements, but the 25-hydroxyvitamin D concentration exceeded the analytic range of the automated analyzer. Further studies showed a monoclonal protein immunoglobulin G with elevated serum free lambda light chains (73.4 mg/dl; reference range 0.83–2.7 mg/dl). The 1,25-dihydroxyvitamin D level was 28 pg/ml (reference range 25–65 pg/ml)..
Question: Which ONE of the following is the MOST likely cause of this patient’s laboratory proﬁle?
1. Surreptitious intake of vitamin D
2. Sarcoidosis
3. Monoclonal protein causing an artefactual increase in 25-hydroxyvitamin D
4. Plasma cell-induced stimulation of 25-hydroxyvitamin D synthesis
Answer: C
Subject: Disorders of Divalent Ions, Renal Bone Disease and Nephrolithiasis

A 27-year-old man with ESRD secondary to focal and segmental glomerulosclerosis is evaluated 3 weeks after deceased donor kidney transplantation. He had delayed graft function requiring 2 weeks of postoperative hemodialysis. A recent biopsy showed no evidence of rejection and acute tubular injury. Laboratory studies show a sodium of 138 mEq/L, potassium of 5.7 mEq/L, chloride of 107 mEq/L, total CO2 of 19 mmol/L, BUN of 46 mg/dl, creatinine of 3.8 mg/dl, glucose of 126 mg/dl, calcium of 10.3 mg/dl, magnesium of 1.0 mg/dl, and phosphorus of 5.2 mg/dl..
Question: In addition to the patient’s immunosuppressive medications, which ONE of the following fac-tors is associated with an increased risk for the development of diabetes mellitus in the year after transplantation?
1. Hypomagnesemia
2. Hyperkalemia
3. Hypercalcemia
4. Hyperphosphatemia
Answer: A
Subject: Disorders of Divalent Ions, Renal Bone Disease and Nephrolithiasis

A 58-year-old woman is referred for evaluation and management of sarcoidosis-related hypercalcemia. She presented with fever, arthralgias, and fatigue of 2 weeks duration. Laboratory studies showed a serum calcium of 11.4 mg/dl, a serum phosphorus of 4.0 mg/dl, a BUN of 42 mg/dl, a creatinine of 1.6 mg/dl, a PTH level of 10 pg/ml (reference range 12–72 pg/ml), a 25-hydroxyvitamin D level of 35 ng/ml (reference range 20–80 ng/ml), and a 1,25-dihydroxy vitamin D level of 106 pg/ml (reference range 25–65 pg/ml). CT of the chest revealed pretracheal and paratracheal, subcarinal, and bilateral hilar lymph node enlargement. Transbronchial needle aspiration of a subcarinal lymph node revealed noncaseating granulomatous lymphadenitis. The patient was treated with prednisone 40 mg daily. The acute kidney injury and hypercalcemia improved, but she gained 9 kg in weight, she had difﬁcult-to-control hyperglycemia, and a Cushingoid appearance developed..
Question: At this point, which ONE of the following would you recommend for treatment of this woman’s hypercalcemia?
1. Zoledronic acid
2. Calcitonin
3. Denosumab
4. Phenytoin
5. Cinacalcet
Answer: A
Subject: Disorders of Divalent Ions, Renal Bone Disease and Nephrolithiasis

You are asked to see a 44-year-old man in consultation for severe hypercalcemia. He has had progressive fatigue and generalized bone pain over the past 3 months. He does not have confusion, polyuria, polydipsia, renal colic, nausea, constipation, or abdominal pain. He was previously in excellent health and was taking no medications except for acetaminophen on an as needed basis for bone pain. Laboratory data showed a serum sodium of 140 mEq/L, potassium of 4.5 mEq/L, chloride of 115 mEq/L, total CO2 of 24 mmol/L, anion gap of 1 mmol/L, BUN of 20 mg/dl, creatinine of 0.9 mg/dl, glucose of 78 mg/dl, serum calcium of 15.9 mg/dL, albumin of 3.9 g/dl, phosphorus of 2.3 mg/dl, PTH of 19 pg/ml (reference range 12–72 pg/ml), 25-hydroxyvitamin D level of 32 ng/ml (reference range 20–80 ng/ml), hemoglobin of 10.5 g/dl, and erythrocyte sedimentation rate of 45 mm/h (reference range 0–22 mm/h)..
Question: Which ONE of the following should you recommend at this time?
1. Zoledronic acid
2. Hemodialysis
3. Ionized calcium
4. Calcitonin
5. PTH-related protein level
Answer: C
Subject: Disorders of Divalent Ions, Renal Bone Disease and Nephrolithiasis
Question: Question 5553
Which ONE of the following statements regarding the association between uric acid and kidney stone formation is CORRECT?
1. Increased serum uric acid is a risk factor for stone formation in men without a previous history of stone formation
2. Lowering serum uric acid reduces the risk of calcium stone formation
3. Increased serum uric acid is a risk factor for stone formation in women without a previous history of stone formation
4. Serum uric acid predicts the risk of uric acid stone, but not calcium stone, formation
5. Patients with hyperuricemia usually have hyperuricosuria
Answer: A
Subject: Disorders of Divalent Ions, Renal Bone Disease and Nephrolithiasis

A 22-year-old man with a history of a motor vehicle accident 5 months ago is evaluated in the emergency department for worsening and possibly infected sacral decubitus ulcers and intermittent substernal chest pain. He sustained multiple sacral, pelvic, and femur fractures, and he has remained bedridden at home. He has had intractable pain that has precluded full participation in home physical therapy. A physical examination reveals multiple sacral and heel decubitus ulcers with serosanguinous drainage. He is unable to walk, sit, or roll over without assistance secondary to pelvic girdle pain. The result of his cardiopulmonary examination is normal except for resting tachycardia. Laboratory studies reveal normal levels of serum sodium, potassium, chloride, bicarbonate, and serum troponin. The EKG shows shortened QoTc (b180 ms) and QaTc (b300 ms) intervals as well as ST segment/T wave abnormalities..
Question: Which ONE of the following is the next BEST step in the evaluation of this patient?
1. Refer for cardiac catheterization
2. Chest CT
3. Serum calcium
4. Serum magnesium
5. Cardiac ultrasonography
Answer: C
Subject: Disorders of Divalent Ions, Renal Bone Disease and Nephrolithiasis

A 50-year-old woman is referred for evaluation of recurrent nephrolithiasis. She has had a long history of recurrent urinary tract infections and has received multiple antibiotics in an attempt to suppress her infections. The results of her laboratory studies are serum sodium 138 mEq/L, potassium 3.9 mEq/L, chloride 105 mEq/L, total CO2 24 mmol/L, BUN 18 mg/dl, creatinine 1.2 mg/dl, calcium 8.9 mg/dl, albumin 4.0 g/dl, magnesium 2.3 mg/dl, and uric acid 4 mg/dl. A urinalysis reveals a pH of 7 and many leukocytes and bacteria on microscopic examination. Stone analysis in the past was consistent with struvite stones. A ﬂat plate radiograph of the abdomen shows a right staghorn calculus..
Question: In addition to a urine culture, which ONE of the following is the MOST appropriate next diagnostic test for this patient?
1. 24-hour urine metabolic evaluation
2. Urine osmolal gap
3. Serum PTH level
4. Serum 1,25-dihydroxyvitamin D level
Answer: A
Subject: Disorders of Divalent Ions, Renal Bone Disease and Nephrolithiasis

A 29-year-old man was evaluated in the emergency department because of 5 days of persistent emesis. He had previously been in good health, with no interactions with the health care system. He admitted to habitual use of cannabis. He described muscle weakness as well. A physical examination revealed a well-nourished man, who vomited once during the initial evaluation. The blood pressure was 110/80 mmHg, and the heart rate was 110 mmHg. He had minimal weakness of his upper and lower extremities. Otherwise, the physical examination was normal. Laboratory studies showed a serum sodium of 141 mEq/L, potassium of 3.7 mEq/L, chloride of 105 mEq/L, total CO2 of 21 mmol/L, BUN of 18 mg/dl, and creatinine of 0.84 mg/dl..
Question: At this point, which ONE of the following would you expect on further laboratory assessment?
1. Hypophosphatemia
2. Hyperkalemia
3. Hyperammonemia
4. Hypoalbuminemia
Answer: A
Subject: Disorders of Divalent Ions, Renal Bone Disease and Nephrolithiasis


A 32-year-old woman is referred for evaluation of hypophosphatemia. She had previously been in excellent health, but over the past year she has experienced fatigue, diffuse muscle pain, and generalized weakness. She is not taking any medications. She has no family history of bone or mineral metabolism disorders. She had normal growth and development during childhood. She does not use alcohol or tobacco. Her general physician treated her for iron deﬁciency anemia because of heavy menstrual bleeding 7 weeks earlier. She received 2 doses of parenteral ferric carboxymaltose 500 mg before presentation to your ofﬁce. She does not have diarrhea or weight loss. The result of a physical examination is unremarkable. The results of laboratory studies, including serum electrolytes, calcium, magnesium, and albumin, are all normal except for a serum phosphorus level of 1.6 mg/dl..
Question: Which ONE of the following is the MOST likely cause of her hypophosphatemia?
1. Oncogenic osteomalacia
2. Occult hyperparathyroidism
3. Poor phosphate intake
4. Ferric carboxymaltose infusions
5. Autosomal dominant hypophosphatemia
Answer: D
Subject: Disorders of Divalent Ions, Renal Bone Disease and Nephrolithiasis

A 75-year-old woman is evaluated for diffuse joint and bone pain, most prominent in the low back and hips, for the past 6 months. She has had no other signiﬁcant medical problems. She takes ibuprofen for her pain. The physical examination shows diffuse muscle weakness. The rest of the examination results are unremarkable. Laboratory studies show normal serum electrolytes, a BUN of 16 mg/dl, creatinine of 1.0 mg/dl, calcium of 9.8 mg/dl, phosphorus of 1.6 mg/dl, fractional excretion of ﬁltered phosphate of 18%, PTH of 20 pg/ml (reference range 12–72 pg/ml), and 1,25-dihydroxyvitamin D level of 30 pg/ml (reference range 25–65 pg/ml). Radiographs of the pelvis and hips reveal osteopenia with thinning of the cortex and Looser pseudofractures. Spine radiographs show concave vertebral bodies (codﬁsh vertebrae) with large and biconvex vertebral disks..
Question: Which ONE of the following is the MOST likely cause of this patient’s clinical problem?
1. Ankylosing spondylitis
2. Adynamic bone disease
3. Tumor-induced osteomalacia
4. Osteitis ﬁbrosa cystica
Answer: C
Subject: Disorders of Divalent Ions, Renal Bone Disease and Nephrolithiasis
Question: Question 5559

Higher levels of which ONE of the following factors, even if within the normal range, has been shown to be SIGNIFICANTLY associated with an increased risk of new-onset nephrolithiasis in an otherwise healthy male population with otherwise normal serum chemistry values?
1. PTH level
2. Serum calcium
3. Serum phosphorus
4. Serum calcitonin
5. Serum 1,25-dihydroxyvitamin D
Answer: E
Subject: Disorders of Divalent Ions, Renal Bone Disease and Nephrolithiasis

A 40-year-old man is evaluated for new-onset ﬂank pain and hematuria. Ultrasonography revealed three stones in the left kidney but no hydronephrosis. The results of renal function and routine laboratory studies, including calcium, phosphate, total CO2, and uric acid were all within normal limits. The urine pH was 6.8. His symptoms remitted after 2 days of analgesic medication. He was seen in follow-up, and an abdominal ﬂat plate radiograph was normal. However, repeated ultrasonography showed virtually no change from the earlier ultrasound examination..
Question: Which ONE of the following is the MOST likely cause of this patient’s kidney stones?
1. Hypercalciuria
2. Renal tubular acidosis
3. Hypocitraturia
4. Increased 2,8-dihydroxyadenine excretion
5. Increased uric acid excretion
Answer: D
Subject: Disorders of Divalent Ions, Renal Bone Disease and Nephrolithiasis

A 56-year-old woman is seen in consultation for symptomatic hypomagnesemia. She had been in good health except for recurring symptoms of gastrointestinal reﬂux, for which she was prescribed esomeprazole. Over the past 6 months, she has experienced generalized weakness and intermittent muscle cramps and spasm. She has a history of hypertension for which she was prescribed a thiazide diuretic. She has had no other medical problems. A physical examination reveals a positive Chvostek sign. Laboratory studies show a serum sodium of 138 mEq/L, potassium of 3.9 mEq/L, chloride of 105 mEq/L, total CO2 of 24 mmol/L, BUN of 18 mg/dl, creatinine of 1.2 mg/dl, calcium of 9.6 mg/dl, phosphorus of 4.2 mg/dl, and magnesium of 0.8 mg/dl. The fractional excretion of magnesium is 0.7%. A 24-hour urine determination shows a daily magnesium excretion of 4 mg..
Question: Which ONE of the following is the MOST likely explanation of her hypomagnesemia?
1. Renal losses induced by a speciﬁc mutation in the TRMP6 gene
2. Renal losses induced by thiazide diuretics
3. Renal losses induced by a defect in the Claudin-16 gene
4. Decreased gastrointestinal absorption
Answer: D
Subject: Disorders of Divalent Ions, Renal Bone Disease and Nephrolithiasis

You are monitoring a 28-year-old woman who has had three episodes of nephrolithiasis in the past 7 years. Studies in the past have been unrevealing, with normal values for calcium, phosphate, urinary pH, urine calcium, and serum PTH. She has been treated with increased ﬂuid intake and liberal dietary calcium. She takes vitamin C 1000 mg daily and asks you about the impact of this on her risk for subsequent kidney stones..
Question: Which ONE of the following should you tell her about the use of vitamin C regarding kidney stone risk?
1. Her vitamin C use places her at increased risk for recurrent stones
2. Increased stone risk with vitamin C supplementation is seen only in men
3. Cohort studies do not include sufﬁcient numbers of vitamin C users to assess risk
4. There is no increased risk of kidney stones with vitamin C because it is chemically converted to oxalate only after excretion in the urine
5. Her use of vitamin C supplements does not place her at increased risk because she is not hypercalciuric
Answer: B