hllj/quesmed huggingface dataset:
Which of the following conditions is caused by the chromosomal karyotype shown in the above image?

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Options:
explanation: Down Syndrome is caused by the karyotype 47, XY/XX, +21  trisomy 21, which is when an additional copy or portion of chromosome 21 is inherited. Here you can see three copies of chromosome 21.
name: Down Syndrome
label: a
answer: yes
explanation: The karyotype for Klinefelter Syndrome is 47XXY, meaning the syndrome only affects males and is caused by an extra copy of the X chromosome. This image shows a normal number of X chromosomes.
name: Klinefelter Syndrome
label: c
answer: no
explanation: Turner syndrome is a disorder affecting females only, and leads to affected individuals having an absent, or partially absent X chromosome, making the karyotype 45XO. This image shows both X chromosomes fully in-tact.
name: Turner syndrome
label: b
answer: no
explanation: The karyotype for Edward's syndrome is trisomy 18 (47, XY/XX, +18). This image shows three copies of chromosome 21, not chromosome 18.
name: Edward's syndrome
label: d
answer: no
explanation: The karyotype for Patau Syndrome is trisomy 13 (47, XY/XX, +13). This image shows three copies of chromosome 21, not chromosome 13.
name: Patau Syndrome
label: e
answer: no

Correct answer: a
A 60-year-old man with no significant past medical history presents with a two-month history of weight loss, night sweats, fatigue and repeated chest infections. On examination, he has enlarged cervical lymph nodes and palpable splenomegaly. The results from his initial full blood count are shown below. Which of the following differential diagnoses is most likely at this stage?
 

|                |         |                   |
| -------------- | :-------: | --------------- |
| Haemoglobin    |        104 g/L   | (M) 130 - 170, (F) 115 - 155 |
| Mean Cell Volume (MCV)                   | 90 fL                  | 80 - 96       |
| White Cell Count   |     67.3x10<sup>9</sup>/L   | 3.0 - 10.0      |
| Platelets          |     120x10<sup>9</sup>/L            | 150 - 400     |
| Red blood cells |  3.53 x 10<sup>9</sup>/L                 | 4.50 - 6.50      |
| Haematocrit | 31.9%                  | 40 - 54       |

Options:
explanation: This would explain the patient's thrombocytopenia (low platelets), and may also explain the splenomegaly. However, the symptoms would be purpura of the legs and increased bleeding. There would also be no effect on the WCC, and so increased infection rates would not be expected, and the RBC count would also remain within normal ranges.
name: Immune thrombocytopenic purpura
label: e
answer: no
explanation: Asthma would not lead to any of these symptoms, and we would not expect any changes on a FBC.
name: Asthma
label: c
answer: no
explanation: Anaemia of chronic disease is a good differential as it can cause a normocytic anaemia. However, the raised WCC and presenting symptoms are more suggestive of an underlying malignancy.
name: Anaemia of chronic disease
label: d
answer: no
explanation: Whilst this fits with the 'repeated chest infections' part of the patient history, it would be unlikely for pneumonia to cause symptoms such as splenomegaly and night sweats - although a general fever may be present. A two-month history is also a chronic presentation for something such as an infection. The WCC is also very high for an infection, and instead suggests a haematological cancer.
name: Community-acquired pneumonia
label: b
answer: no
explanation: The patient's history gives red flag symptoms of cancer, such as unintentional weight loss and night sweats. Splenomegaly is a key sign of chronic lymphocytic leukaemia, and is caused by the production of malignant cells within the spleen. Enlarged lymph nodes also occur due to the proliferation of malignant cells. The repeated chest infections are due to the malignant lymphocytes being unable to fight off infection. The blood results show raised WCC due to the malignancy, low platelets (thrombocytopenia) and anaemia due to lack of space in the bone marrow for red blood cell development. The patient is also within the key age-range for this leukaemia.
name: Chronic lymphoid leukaemia
label: a
answer: yes

Correct answer: a
A sample of bacteria was added to the coagulase-containing test tube labelled A. Test tube B is left for comparison. Which of the following bacteria may test tube A contain?

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Options:
explanation: *S. haemolyticus* is a coagulase-negative bacteria - so would not cause a positive coagulase test such as the one seen in test tube A.
name: *Staphylococcus haemolyticus*
label: c
answer: no
explanation: Test tube A shows a positive coagulase test as macroscopic clotting has occurred. This can be a positive identification of *S. aureus* which is a coagulase-positive bacteria.
name: *Staphylococcus aureus*
label: a
answer: yes
explanation: All streptococcus bacteria are catalase-positive and coagulase-negative, so this would not cause a positive coagulase test.
name: *Streptococcus pneumoniae*
label: e
answer: no
explanation: *S. epidermis* is a coagulase-negative bacteria - so would not cause a positive coagulase test such as the one seen in test tube A.
name: *Staphylococcus epidermis*
label: b
answer: no
explanation: All streptococcus bacteria are catalase-positive and coagulase-negative, so this would not cause a positive coagulase test.
name: *Streptococcus pyogenes*
label: d
answer: no

Correct answer: a
The following diagram shows a T-cell interacting with an antigen-presenting cell (APC). Which of the labelled areas on the diagram corresponds to the major histocompatibility (MHC) molecule?

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Options:
explanation: 'C' corresponds to antigens both being presented by the MHC molecule (B) and within the APC (D).
name: C
label: c
answer: no
explanation: The MHC molecule is labelled by arrow B.
name: None of the above
label: e
answer: no
explanation: The area labelled 'A' corresponds to the T cell surface receptor. It sits on the surface of the T-cell and recognises the antigens presented by the MHC molecule (B) by the antigen-presenting cell (D).
name: A
label: b
answer: no
explanation: 'D' corresponds to the antigen-presenting cell itself, which uses the MHC molecule (B) to present antigens to the T-cell receptors (A).
name: D
label: d
answer: no
explanation: The MHC molecule presents the antigen (labelled 'C') to the T-cell receptor (labelled 'A') so that the antigen is able to be recognised by the T cell.
name: B
label: a
answer: yes

Correct answer: a
A 45-year-old woman presents with severe pain in her lower right leg. She ranks the pain a 10/10 when asked. Examination reveals minor swelling and erythema to the area as well as it being warm to the touch. She also has a fever of 39.7C.

What is the most appropriate management of this patient?

Options:
explanation: Analgesia is a good idea considering this patient has severe pain. However, given its severity, a stronger choice may be more appropriate e.g. morphine or codeine. Also, there is little indication for fluids at this point as we do not know her blood pressure or hydration status.
name: NSAIDs and supportive IV fluids
label: c
answer: no
explanation: Whilst this would help with the infection, it would not treat the underlying infection of the deep tissue - removal of the infection tissue via surgical debridement is needed to ensure all infection is treated.
name: Broad-spectrum IV antibiotics only
label: b
answer: no
explanation: This is the correct treatment pathway for necrotising fasciitis, which is what this patient is presenting with. Typical symptoms of necrotising fasciitis include pain which is out of proportion to clinical findings, skin discolouration, fever, and local swelling. Urgent surgical debridement is needed to remove the infected tissue to prevent the spread of the infection, and antibiotics are needed to treat the infection.
name: Broad-spectrum IV antibiotics and urgent surgical debridement
label: a
answer: yes
explanation: This is the treatment for an anaphylactic reaction (severe type 1 hypersensitivity reaction), which is not what this patient is presenting with. In a anaphylactic reaction, we would see airway and/or circulation compromise with a rapid onset of allergic symptoms such as wheeze and urticaria, rather than this patient's fever and severe pain which suggests an infection.
name: IM adrenaline
label: e
answer: no
explanation: This may be indicated if this case was a suspected deep vein thrombosis, which would present with pain and swelling of the lower leg. However, the severe pain and fever are more suggestive of a significant infection- necrotising fasciitis. This requires urgent IV antibiotics and surgical debridement.
name: Oral rivaroxaban
label: d
answer: no

Correct answer: a
A sputum culture taken from a patient is stained using a Ziehl-Neelsen stain.

Which of the following organisms is this staining process used to identify?

Options:
explanation: Streptococci are gram-positive bacteria which would best be detected by a gram stain.
name: *Streptococcus pneumoniae*
label: d
answer: no
explanation: PJP can be detected using a variety of stains. However, it is usually detected using the Beta-D-Glucan blood test which identifies the cell wall present in this type of fungi.
name: *Pneumocystis jirovecii* pneumonia (PJP)
label: c
answer: no
explanation: Zeihl-Neelsen staining is used to test for TB. The sample is stained, heated and washed in an acid solution. The TB bacteria (*Mycobacterium tuberculosis*) are resistant to the acid wash and remain stained so are described as acid-fast bacilli. They appear as distinctive bright-red bacilli against a blue background.
name: Tuberculosis (TB)
label: a
answer: yes
explanation: *H. influenzae* can be tested for by gram-staining, appearing as small gram-negative coccobacilli.
name: *Haemophilus influenzae*
label: b
answer: no
explanation: This is an infection caused by inhalation of aspergillus (a common type of mould). Silver stains (e.g. a Gridley stain) are used to stain Aspergillus.
name: Aspergillus
label: e
answer: no

Correct answer: a
Which of the following innervates the mediastinal parietal pleura?

Options:
explanation: This is the nerve which innervates the mediastinal parietal pleura - which is part of the outer layer of the pleura (parietal layer) and sits on the medial part of the lung.
name: Phrenic nerve
label: a
answer: yes
explanation: These provide innervation to the parietal costal pleura - which is part of the outer layer of the pleura (parietal layer) and sits on the lateral side of the lungs against the thoracic cage.
name: First to eleventh intercostal nerves
label: e
answer: no
explanation: This provides autonomic innervation to the visceral pleura - which is the inner pleura directly lining the lungs.
name: Pulmonary plexuses
label: d
answer: no
explanation: This is the nerve which innervates the cervical parietal pleura - which is part of the outer layer of pleura (parietal layer) and sits at the apex of the lung.
name: First intercostal nerve
label: b
answer: no
explanation: These nerves supply the diaphragmatic parietal pleura - which is part of the outer layer of the pleura (parietal layer) and sits above the diaphragm.
name: Lower intercostals and phrenic nerves
label: c
answer: no

Correct answer: a
Which of the following vessels drain into the coronary sinus?

Options:
explanation: The coronary sinus receives blood from these four major cardiac veins, and acts as the largest vein draining the myocardium.
name: Great cardiac vein, posterior cardiac vein, small cardiac vein, and middle cardiac vein
label: a
answer: yes
explanation: These two veins do drain into the coronary sinus. However, there are four veins which drain into the sinus, the additional two veins being the great cardiac vein and the small cardiac vein.
name: Middle cardiac vein and posterior cardiac vein only
label: e
answer: no
explanation: These are the branches of the right coronary artery. They supply oxygenated blood to the right side of the myometrium. Only veins, which carry deoxygenated blood, drain into the coronary sinus.
name: Right marginal artery and sino-atrial nodal artery
label: d
answer: no
explanation: These two veins do drain into the coronary sinus. However, there are four veins in total which drain into the sinus. The additional two veins are the middle cardiac vein and the posterior cardiac vein.
name: Great cardiac vein and small cardiac vein only
label: c
answer: no
explanation: The coronary sinus is a vein, and so only veins drain into it. The right and left coronary arteries arise from the ascending aorta and supply oxygenated blood to the heart.
name: Right and left coronary arteries
label: b
answer: no

Correct answer: a
A 75-year-old female is diagnosed with a pancoast tumour. She also complains of having a hoarse voice over recent months.

Where is the likely location of her tumour?

Options:
explanation: Pancoast tumours only affect the lung apecies, and if they occur within the left lung may lead to recurrent laryngeal nerve compression - causing vocal cord paralysis, thus explaining this patient's hoarse voice.
name: Left lung apex
label: a
answer: yes
explanation: Pancoast tumours are found exclusively within the lung apex's. However, this patient's vocal hoarseness is likely due to vocal cord paralysis due to compression of her left recurrent laryngeal nerve by a tumour on the left side.
name: Right lung apex
label: b
answer: no
explanation: Pancoast tumours are found in the lung apex, not the base of the lungs.
name: Left lung base
label: c
answer: no
explanation: While, if left untreated, a pancoast tumour may grow to extend towards the middle lobe, it would have begun within the apex. Also, to cause vocal paralysis it would likely have occurred on the left side.
name: Right middle lobe
label: e
answer: no
explanation: Pancoast tumours are found in the lung apex, not in the base of the lungs.
name: Right lung base
label: d
answer: no

Correct answer: a
A 28-year-old female with a history of Crohn's disease presents with a month-long history of fatigue and shortness of breath.


Her FBC is as follows:


||||
|--------------|:-------:|---------------|
|Haemoglobin|70  g/L|(M) 130 - 170, (F) 115 - 155|
|White Cell Count|4.9x10<sup>9</sup>/L|3.0 - 10.0|
|Platelets|192x10<sup>9</sup>/L|150 - 400|
|Mean Cell Volume (MCV)|113.7 fL|80 - 96|
|Red blood cells|2.05 10<sup>12</sup>/L|3.8 - 4.8|


Which of the following best describes the pattern seen in the blood tests?

Options:
explanation: The low Hb and RBC mean that the patient has anaemia. The raised MCV means that the anaemia is macrocytic (large RBCs). Given the patient's history of Crohn's disease, she likely has poor absorption of B12 and folate, thus causing a macrocytic megaloblastic anaemia. This could be confirmed by testing her serum B12 and folate levels.
name: Macrocytic megaloblastic anaemia
label: a
answer: yes
explanation: Microcytic anaemia means a low MCV, which indicates small RBCs. This patient has a raised MCV, indicating large RBCs, meaning they must have a macrocytic anaemia.
name: Microcytic anaemia
label: d
answer: no
explanation: This patient has a raised MCV. Therefore the anaemia must be macrocytic as the RBCs are large. Normocytic anaemia refers to an anaemia with a within-range MCV.
name: Normocytic anaemia
label: c
answer: no
explanation: Anaemia of chronic disease is a cause of microcytic or normocytic anaemia, causing a low/normal MCV. It often occurs due to cancer. As this patient has a raised MCV, indicating large RBCs, they cannot have anaemia of chronic disease.
name: Anaemia of chronic disease
label: e
answer: no
explanation: The anaemia is macrocytic due to the high MCV. However, it is much more likely to be caused by a B12 or folate deficiency given the patient's history of Crohn's disease. Normoblastic anaemia is more likely in patients with histories of alcoholism or hypothyroidism. We could rule this out by testing her serum B12 and folate levels.
name: Macrocytic normoblastic anaemia
label: b
answer: no

Correct answer: a
A 74-year-old is found to have a deep-vein-thrombosis (DVT) on doppler ultrasound. His CrCl is 24ml/min and he takes 300mg OD Allopurinol for gout.

Which of the following is the most appropriate drug for the immediate treatment of his DVT?

Options:
explanation: Unfractionated heparin is rarely used anymore due to its need to be monitored via APTT. Therefore it would not be used first-line.  However, it is preferred to low molecular weight heparin in patients with reduced CrCl.
name: Unfractionated heparin
label: d
answer: no
explanation: This is a DOAC (direct oral anticoagulant) and is an appropriate treatment for a DVT. However, it should only be used when CrCl > 30ml/min.
name: Dabigatran
label: b
answer: no
explanation: Patients with suspected DVT should be managed with treatment dose rivaroxaban (or apixaban alternatively) first-line. It is a DOAC (direct oral anticoagulant), and is safe to give at a reduced dose in patients with CrCl below 30ml/min.
name: Rivaroxaban
label: a
answer: yes
explanation: Aspirin is an anti-platelet drug which may be used for secondary prevention of a DVT in patients who decline anticoagulant drugs. However, it would not be used first-line for this patient.
name: Aspirin
label: e
answer: no
explanation: This is a type of low-molecular weight heparin, which can be used to treat DVTs. However, it is not typically used first-line for treatment, more so for thromboprophylaxis. It also cannot be used in patients with CrCl <30ml/min.
name: Enoxaparin
label: c
answer: no

Correct answer: a
The above image shows a gel card of a patient's blood sample. Which of the following is the patient's correct blood type?

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Options:
explanation: The blood cannot be group A as the cells do not agglutinate with anti-A. It also must be Rh +'ve as the cells agglutinate with anti-D.
name: Group A Rh -'ve
label: d
answer: no
explanation: The blood cells are negative for anti-A and anti-B, meaning it is type O (as they contain neither A nor B antigens, and so do not agglutinate). The cells are then positive for anti-D, meaning they do have D antigens, making the blood Rh +'ve. The reverse matching in the final two tubes confirms the O-type blood by mixing the patient's plasma with A and B RBCs, which causes a positive result as type O plasma contains both A and B antibodies.
name: Group O Rh +'ve
label: a
answer: yes
explanation: This is the reverse interpretation of the results. Remember that the antibodies are in the plasma, and the antigens are on the RBC surface.
name: Group AB Rh -'ve
label: b
answer: no
explanation: The blood is group O as its cells do not agglutinate with anti-A or anti-B, and group O blood cells do not have A or B antigens. However, it is Rh +'ve as the cells agglutinate with anti-D.
name: Group O Rh -'ve
label: e
answer: no
explanation: The gel card shows that the patient's blood cells do not contain B antigens as they do not agglutinate with anti-B, therefore it cannot be group B. However, it is Rh +'ve, as seen by the blood cells agglutinating with anti-D.
name: Group B Rh +'ve
label: c
answer: no

Correct answer: a
Which of the following best describes the effect of increased blood CO<sub>2</sub> on the oxygen-haemoglobin (Hb) dissociation curve?

Options:
explanation: The curve shifts to the right (rightward shift) to reflect the decreased affinity of Hb for O<sub>2</sub> due to CO<sub>2</sub> now taking up more of the Hb binding sites.
name: No change in position or shape of the curve
label: c
answer: no
explanation: This would indicate the Hb having an increased affinity for O<sub>2</sub>, and as the Hb binding sites are taken up by CO<sub>2</sub> due to the increased CO<sub>2</sub> concentration, it instead has a decreased affinity and so shifts to the right.
name: Leftward shift
label: b
answer: no
explanation: Only rightward or leftward shifts are seen in oxygen-haemoglobin dissociation curves, specifically a rightward shift when CO<sub>2</sub> is increased.
name: Downward shift
label: e
answer: no
explanation: A hyperbolic (AKA exponential) curve is seen in myoglobin (Mb), not haemoglobin (Hb).
name: The curve becomes hyperbolic in shape rather than S-shaped
label: d
answer: no
explanation: Increased CO<sub>2</sub> in the blood causes a decreased affinity of Hb for O<sub>2</sub> which then leads to the oxygen-Hb dissociation curve shifting to the right, as the Hb is less saturated with O<sub>2</sub>.
name: Rightward shift
label: a
answer: yes

Correct answer: a
A 16-year-old male presents with occasional episodes of breathlessness. He has a past medical history of rheumatic fever from when he was 10-years-old. On auscultation, a mid-diastolic rumbling murmur is heard alongside a loud S1.

What valvular pathology is most likely to be responsible for this murmur?

Options:
explanation: Mitral stenosis is heard as a low-pitched 'rumbling' mid-diastolic murmur as the stenosis restricts blood flow across the mitral valve from the left atrium into the left ventricle. The first heart sound (S1) is then heard due to the large systolic force required to snap shut the thickened mitral valve. Rheumatic fever is also a very common cause of mitral stenosis, and breathlessness often occurs as a consequence due to pulmonary congestion.
name: Mitral stenosis
label: a
answer: yes
explanation: Breathlessness may occur due to pulmonary oedema. However, syncope and angina are also often present. Also, whilst the murmur heard in aortic regurgitation is diastolic, it is a much shorter murmur, only heard at the beginning of diastole (and also sometimes at the end of systole).
name: Aortic regurgitation
label: c
answer: no
explanation: Rheumatic fever is a cause of mitral regurgitation, and it may also cause breathlessness due to back pressure on the pulmonary circulation. However, the murmur heard would be a pan-systolic, high-pitched 'whistling' murmur due to high-velocity blood flow through the leaky valve.
name: Mitral regurgitation
label: b
answer: no
explanation: The heart sounds heard in mitral valve prolapse are a mid-systolic 'click' as the valve prolapses back into the left atrium, sometimes followed by a late systolic murmur if blood then continues to flow into the left atrium.
name: Mitral valve prolapse
label: d
answer: no
explanation: Aortic stenosis causes an ejection-systolic crescendo-decrescendo murmur, which is often high-pitched due to the high velocity of systole. Exertional syncope is the most common symptom of aortic stenosis, and rheumatic heart disease is a cause.
name: Aortic stenosis
label: e
answer: no

Correct answer: a