NEET-PG 2012 — Internal Medicine
107 Previous Year Questions with Answers & Explanations
Haemoglobin F is raised in which condition?
All are seen in pheochromocytoma except which of the following?
Which type of fatty acids should be included in the diet to manage chyluria?
In which condition is venous blood most commonly observed to have a high hematocrit in routine clinical practice?
Renal vein thrombosis is associated with all of the following conditions except:
Which of the following complications is commonly associated with mitral valve prolapse?
All of the following statements about the third heart sound (S3) are true, except:
Which of the following is an acquired condition?
Which of the following is the most characteristic symptom of obstruction of the inferior vena cava?
What is the most common cause of dissecting hematoma?
NEET-PG 2012 - Internal Medicine NEET-PG Practice Questions and MCQs
Question 1: Haemoglobin F is raised in which condition?
- A. Hereditary persistence of fetal hemoglobin (HPFH)
- B. Beta-thalassemia major
- C. Sickle cell disease
- D. Juvenile chronic myeloid leukemia (Correct Answer)
Explanation: ***Juvenile chronic myeloid leukemia*** - This condition is characterized by a high proportion of **fetal hemoglobin (HbF)**, often exceeding 50%, alongside other typical myeloproliferative features. - The elevated HbF is a distinguishing feature of **juvenile CML** from adult CML, which typically presents with normal or only slightly elevated HbF levels. *Beta-thalassemia major* - While patients with **beta-thalassemia major** can have elevated HbF, it is typically in response to a severe deficiency in beta-globin chain production, leading to compensatory gamma-chain synthesis. - However, the primary genetic defect lies in the beta-globin genes, and the HbF increase is usually not as universally high or definitive as in HPFH or juvenile CML. *Sickle cell disease* - Patients with **sickle cell disease** can have variable levels of HbF, and higher levels are associated with a milder disease course [1]. - HbF acts as a protective factor by inhibiting hemoglobin S polymerization, but the presence of high HbF is not a diagnostic marker in the same way it is for HPFH or juvenile CML [1]. *Hereditary persistence of fetal hemoglobin (HPFH)* - This is a benign condition characterized by the **continued production of high levels of HbF into adulthood** due to genetic mutations that prevent the normal developmental switch from gamma-globin to beta-globin synthesis. - While it features significantly raised HbF, HPFH is typically **asymptomatic** and does not present with the myeloproliferative features seen in juvenile CML.
Question 2: All are seen in pheochromocytoma except which of the following?
- A. Headaches
- B. Weight loss
- C. Sweating attacks
- D. Hypotension (Correct Answer)
Explanation: ***Hypotension*** - Pheochromocytoma is characterized by the **overproduction of catecholamines** (epinephrine and norepinephrine), which typically cause **hypertension** rather than hypotension. - The classic symptoms of pheochromocytoma, often described as the "5 Ps," are **pain (headache)**, **palpitations**, **perspiration**, **pallor**, and **paroxysmal hypertension**. *Headaches* - **Severe, throbbing headaches** are a very common symptom in pheochromocytoma due to the **vasospastic effects** of high circulating catecholamines. - These headaches are often sudden in onset and can be debilitating. *Weight loss* - The **hypermetabolic state** induced by excessive catecholamines can lead to **increased caloric expenditure** and subsequently, **weight loss**. - Catecholamines increase **basal metabolic rate** and breakdown of fat stores. *Sweating attacks* - **Diaphoresis** or profuse sweating attacks are a hallmark symptom, caused by **sympathetic nervous system activation** due to high catecholamine levels. - These attacks are often paroxysmal and can be accompanied by an exacerbation of other symptoms.
Question 3: Which type of fatty acids should be included in the diet to manage chyluria?
- A. Short-chain fatty acids
- B. Medium-chain fatty acids (Correct Answer)
- C. Long-chain fatty acids
- D. Omega-3 fatty acids
Explanation: ***Medium-chain fatty acids*** - **Medium-chain fatty acids (MCFAs)** are absorbed directly into the **portal circulation** without being re-esterified to triglycerides or incorporated into chylomicrons [1]. This helps bypass the compromised lymphatic system. - In **chyluria**, the lymphatic system's integrity is disrupted, leading to leakage of **chyle** (lymphatic fluid rich in chylomicrons) into the urinary tract. MCFAs provide a source of fat that does not rely on the lymphatic pathway for transport [1]. *Short-chain fatty acids* - **Short-chain fatty acids (SCFAs)** are primarily produced by bacterial fermentation in the colon and are absorbed directly into the portal circulation. - While they do not rely on the lymphatic system, their dietary contribution as a significant energy source is limited, and they are not the primary fat source for patients with chyluria. *Long-chain fatty acids* - **Long-chain fatty acids (LCFAs)** are absorbed with the help of bile salts, re-esterified into triglycerides, and packaged into **chylomicrons** within the intestinal cells [2]. - These chylomicrons then enter the **lymphatic system** and eventually the bloodstream, which is precisely the pathway that is compromised in chyluria, making them unsuitable [2]. *Omega-3 fatty acids* - **Omega-3 fatty acids** are a type of **long-chain polyunsaturated fatty acid** that also follow the chylomicron-lymphatic pathway for absorption [3]. - While beneficial for other health aspects, they are not suitable for managing chyluria due to their reliance on the **lymphatic system** for transport, which is dysfunctional in this condition.
Question 4: In which condition is venous blood most commonly observed to have a high hematocrit in routine clinical practice?
- A. Dehydration (Correct Answer)
- B. Anemia
- C. Hypervolemia
- D. Acute blood loss
Explanation: Dehydration - In **dehydration**, the total body water is reduced, leading to a decrease in plasma volume [1, 5]. This concentrates the red blood cells, resulting in a relatively **high hematocrit**. [3] - This is a common finding as the body attempts to conserve fluid, making it a primary cause of **elevated hematocrit** in clinical practice. *Anemia* - **Anemia** is characterized by a decrease in the number of red blood cells or a reduced hemoglobin concentration, which would lead to a **low hematocrit**, not a high one [2]. - This condition involves insufficient oxygen-carrying capacity due to a deficiency in red blood cells or hemoglobin [2]. *Hypervolemia* - **Hypervolemia** describes an excess of fluid in the blood, which would dilute the blood components, leading to a relatively **low hematocrit** [1]. - This condition is often associated with conditions like heart failure or kidney disease, where fluid retention is common. *Acute blood loss* - In **acute blood loss**, the loss of whole blood immediately after the event would initially reduce both red blood cells and plasma proportionally, not immediately raising hematocrit [2]. - As the body attempts to compensate by shifting extravascular fluid into the circulation, this would further dilute the blood, eventually leading to a **decreased hematocrit** [2].
Question 5: Renal vein thrombosis is associated with all of the following conditions except:
- A. Nephrotic syndrome
- B. Dehydration
- C. Sickle cell anemia
- D. Trauma (Correct Answer)
Explanation: **Trauma** - While trauma to the abdomen can cause **renal injury** and other vascular issues, isolated **renal vein thrombosis** is not a common direct association or complication [1]. - Renal vein thrombosis typically results from conditions that lead to a **hypercoagulable state** or local vascular stasis. *Sickle cell anemia* - Individuals with **sickle cell anemia** are prone to **vaso-occlusive crises** from sickled red blood cells obstructing blood flow [2]. - This can lead to **renal medullary ischemia** and infarction, making them highly susceptible to **renal vein thrombosis**. *Nephrotic syndrome* - **Nephrotic syndrome** is a significant risk factor for **renal vein thrombosis** due to the urinary loss of **antithrombin III**, a natural anticoagulant. - This loss creates a **hypercoagulable state**, increasing the likelihood of thrombus formation in renal veins. *Dehydration* - Severe **dehydration** leads to **hemoconcentration** (increased blood viscosity) and reduced blood flow. - These factors promote a **hypercoagulable state**, increasing the risk of thrombotic events, including **renal vein thrombosis**, especially in vulnerable populations like infants or the elderly.
Question 6: Which of the following complications is commonly associated with mitral valve prolapse?
- A. Ventricular arrhythmia
- B. Stroke
- C. Infective endocarditis (Correct Answer)
- D. Mitral stenosis
Explanation: Mitral valve prolapse (MVP) involves myxomatous degeneration of the mitral valve leaflets, which can create a rough surface predisposing to bacterial adhesion and subsequent infective endocarditis [1]. While the overall risk is low, patients with MVP and accompanying mitral regurgitation or thickened leaflets are at higher risk [1]. Patients with valvular heart disease are generally susceptible to bacterial endocarditis, often associated with procedures or dental hygiene [2]. Stroke - Although MVP can sometimes be associated with embolic events (e.g., from thrombi forming on the prolapsing valve), stroke is not considered a commonly associated complication. - The risk of stroke is generally higher in MVP patients with concomitant atrial fibrillation or other cardiovascular risk factors. Mitral stenosis - Mitral valve prolapse is characterized by the displacement of mitral valve leaflets into the left atrium during systole, which can lead to mitral regurgitation [3], not stenosis. - Mitral stenosis involves narrowing of the mitral valve orifice, usually due to rheumatic fever, which is a different pathophysiology [4]. Ventricular arrhythmia - While palpitations (often benign supraventricular ectopy) are common in MVP, clinically significant ventricular arrhythmias are less common. - Severe ventricular arrhythmias are more typically seen with significant underlying myocardial disease or severe mitral regurgitation causing left ventricular dysfunction.
Question 7: All of the following statements about the third heart sound (S3) are true, except:
- A. Seen in Atrial Septal Defect (ASD)
- B. Seen in Ventricular Septal Defect (VSD)
- C. Occurs due to rapid filling of the ventricles during early diastole.
- D. Seen in Constrictive Pericarditis (Correct Answer)
Explanation: ***Seen in Constrictive Pericarditis*** - While constrictive pericarditis can lead to a diastolic sound, it's typically a **pericardial knock**, which is sharper and occurs earlier than an S3, due to abrupt halting of ventricular filling. - A true S3 is a low-pitched sound caused by turbulent blood flow into an overly compliant or volume-overloaded ventricle, which is not the primary mechanism in constrictive pericarditis. *Occurs due to rapid filling of the ventricles during early diastole.* - The S3 heart sound is precisely caused by the **rapid inflow of blood** into a dilated or poorly compliant ventricle during the early, rapid filling phase of diastole [1]. - This rapid distension causes vibrations in the ventricular wall, audible as S3, and is often associated with conditions causing **volume overload** or **ventricular dysfunction**. *Seen in Atrial Septal Defect (ASD)* - Patients with a large ASD have increased blood flow through the tricuspid valve, leading to **right ventricular volume overload** [2]. - This increased volume can cause an **S3** sound, particularly a **right ventricular S3**, due to rapid filling of the overloaded right ventricle [2]. *Seen in Ventricular Septal Defect (VSD)* - A significant VSD leads to a **left-to-right shunt**, increasing blood flow to the pulmonary circulation and subsequently returning to the left atrium and left ventricle. - This **left ventricular volume overload** can result in an audible **left ventricular S3**, reflecting rapid filling of the dilated left ventricle.
Question 8: Which of the following is an acquired condition?
- A. Polymastia (supernumerary breasts)
- B. Polythelia (extra nipples)
- C. Mastitis (Correct Answer)
- D. Amastia (absence of breast tissue)
Explanation: ***Mastitis*** - **Mastitis** is an **inflammatory condition** of the breast, often caused by bacterial infection, particularly common during **lactation** [1]. - It is an **acquired condition** as it develops after birth due to external or internal factors, not present at birth. *Polymastia (supernumerary breasts)* - **Polymastia** is a **congenital condition** where additional breast tissue develops along the **milk line**. - This condition is present at birth and results from *embryological development anomalies*, not acquired later in life. *Polythelia (extra nipples)* - **Polythelia** refers to the presence of **accessory nipples** along the embryonic milk line and is a **congenital anomaly**. - Like polymastia, it is present from birth due to *developmental errors* and is not an acquired condition. *Amastia (absence of breast tissue)* - **Amastia** is a rare **congenital anomaly** characterized by the complete absence of breast tissue, nipple, and areola. - It is a **birth defect**, meaning it is present from birth and not an acquired condition.
Question 9: Which of the following is the most characteristic symptom of obstruction of the inferior vena cava?
- A. Paraumblical dilatation (Correct Answer)
- B. Thoraco-epigastric dilatation
- C. Haemorrhoides
- D. Oesophageal varices
Explanation: ***Paraumbilical dilatation*** - Obstruction of the **inferior vena cava (IVC)** leads to collateral circulation through superficial veins, especially around the umbilicus, causing **paraumbilical dilatation** (caput medusae). - This collateral flow bypasses the obstructed IVC to return blood to the superior vena cava system. *Thoraco-epigastric dilatation* - This pattern of collateral circulation is more characteristic of **superior vena cava (SVC) obstruction**, where blood from the upper body needs to bypass the SVC. - The dilated veins would typically be seen on the chest and upper abdomen, draining towards the femoral veins. *Oesophageal varices* - **Oesophageal varices** are typically caused by **portal hypertension** [1], often secondary to liver cirrhosis, not directly by IVC obstruction. - They represent portosystemic collateral veins, diverging from the portal system to the systemic circulation [1]. *Haemorrhoids* - **Haemorrhoids** are dilated veins in the anal canal, most commonly caused by **straining** during defecation or conditions that increase intra-abdominal pressure [2]. - While they can be a sign of portal hypertension [1], **IVC obstruction** is not their primary or most characteristic cause.
Question 10: What is the most common cause of dissecting hematoma?
- A. Hypertension (Correct Answer)
- B. Marfan syndrome
- C. Iatrogenic causes
- D. Kawasaki disease
Explanation: ***Hypertension*** - **Chronic hypertension** is the most frequent cause of dissecting hematoma (aortic dissection) due to the constant high pressure stressing the arterial wall [1]. - It leads to **medial degeneration** and predisposition to intimal tear, allowing blood to enter the arterial wall [1]. *Marfan syndrome* - While Marfan syndrome is a significant risk factor for aortic dissection due to **connective tissue weakness** (cystic medial necrosis), it is much less common than hypertension [1]. - It primarily affects younger individuals with a genetic predisposition to **fibrillin-1 mutations**. *Iatrogenic causes* - These include complications from medical procedures like **cardiac catheterization** or surgery [1]. - Though a possible cause, iatrogenic dissection is relatively rare compared to spontaneous dissection due to hypertension [1]. *Kawasaki disease* - Kawasaki disease primarily causes **coronary artery aneurysms** in children. - It is not a common cause of aortic dissecting hematoma in adults.