Investigation of choice in pheochromocytoma is:
Which of the following is a characteristic of Yellow-nail syndrome?
Which of the following medications is not typically used in the treatment of malignant malaria?
What is the most common complication of a large Patent Ductus Arteriosus (PDA)?
What is the daily temperature variation in remittent fever?
Which biomarker is typically elevated in the plasma of patients with chronic heart disease?
A person experiences asthma attacks more than twice during the day and at least once during the night. What is the most likely classification of their asthma?
Which of the following is a renal-specific nephropathy associated with HIV?
Which of the following is a characteristic of Wilson's disease?
The most common cause of pontine hemorrhage is
NEET-PG 2012 - Internal Medicine NEET-PG Practice Questions and MCQs
Question 91: Investigation of choice in pheochromocytoma is:
- A. CT scan
- B. Urinary catecholamines (Correct Answer)
- C. MIBG scan
- D. MRI Scan
Explanation: ***Urinary catecholamines*** - Measurement of **24-hour urinary fractionated metanephrines and catecholamines** is the initial **biochemical test of choice**. - These biochemical tests are preferred over plasma levels due to the **episodic release** of hormones from a pheochromocytoma, which can lead to high false-negative rates in single plasma measurements. *CT scan* - While a **CT scan** is a crucial **imaging modality** for localizing a pheochromocytoma once the biochemical diagnosis is established [1], it is not the *initial* diagnostic investigation. - Imaging should be performed only after **biochemical confirmation** to avoid unnecessary investigations of incidental adrenal masses [1]. *MIBG scan* - An **MIBG scan** (metaiodobenzylguanidine scan) is a **functional imaging study** used primarily for **localizing metastatic pheochromocytomas** [1] or for cases where CT/MRI is equivocal. - It is not the initial investigation but rather a **secondary imaging test** [1]. *MRI Scan* - **MRI** is an alternative **imaging modality** to CT for localizing pheochromocytomas [1], especially in pregnant women or when radiation exposure is a concern. - Like CT, it serves as a **localization tool** after biochemical confirmation, not the diagnostic test itself.
Question 92: Which of the following is a characteristic of Yellow-nail syndrome?
- A. Knee joint effusion and lymphedema, associated with discolored nails
- B. Pericardial effusion and lymphedema, associated with discolored nails
- C. Pleural effusion and lymphedema, associated with discolored nails (Correct Answer)
- D. Peritoneal effusion and lymphedema, associated with discolored nails
Explanation: ***Pleural effusion and lymphedema, associated with discolored nails*** - Yellow-nail syndrome is characterized by the triad of **yellow, thickened, slow-growing nails**, **lymphedema**, and **pleural effusions**. - **Pleural effusions** are the most common respiratory manifestation, often chronic and recurrent. *Knee joint effusion and lymphedema, associated with discolored nails* - While **lymphedema** is a feature of Yellow-nail syndrome, **knee joint effusion** is not a primary or defining characteristic of the syndrome. - Joint effusions can occur in various conditions, but Yellow-nail syndrome is specifically associated with serous effusions in cavities like the pleura. *Pericardial effusion and lymphedema, associated with discolored nails* - **Pericardial effusion** is a rare manifestation of Yellow-nail syndrome, not a defining characteristic. - The classic triad includes **pleural effusions**, not pericardial. *Per peritoneal effusion and lymphedema, associated with discolored nails* - **Peritoneal effusion** (ascites) is another rare manifestation of Yellow-nail syndrome, not typically included in its core diagnostic criteria. - The syndrome is predominantly associated with effusions in the **pleural space**.
Question 93: Which of the following medications is not typically used in the treatment of malignant malaria?
- A. Doxycycline
- B. Artesunate
- C. Quinine
- D. Quinolone (Correct Answer)
Explanation: ***Quinolone*** - **Quinolone** antibiotics, while broad-spectrum, are not typically used as primary antimalarial agents due to limited efficacy against *Plasmodium falciparum* and potential for resistance. - Their use in malaria treatment is generally restricted to specific co-infections rather than direct antimalarial efficacy. *Quinine* - **Quinine** has been a cornerstone of severe malaria treatment for many years, especially in regions with limited access to newer artemisinin derivatives. - It works by interfering with the parasite's ability to detoxify heme, thus killing the parasites. *Doxycycline* - **Doxycycline** is an effective antimalarial, particularly as a prophylactic agent and in combination therapy for uncomplicated malaria or as an alternative for severe malaria when other agents are contraindicated. - It inhibits **protein synthesis** in the parasite. *Artesunate* - **Artesunate** is the recommended first-line treatment for severe malaria due to its rapid action and potent parasiticidal effects. - It is an **artemisinin derivative** that produces free radicals toxic to the parasite.
Question 94: What is the most common complication of a large Patent Ductus Arteriosus (PDA)?
- A. Eisenmenger syndrome
- B. Congestive Heart Failure (CHF) (Correct Answer)
- C. Infective endocarditis
- D. None of the options
Explanation: ***Congestive Heart Failure (CHF)*** - A large PDA results in a significant **left-to-right shunt**, increasing pulmonary blood flow and leading to **pulmonary overcirculation**. [1] - This increased workload on the heart, particularly the left atrium and ventricle, can lead to **ventricular dysfunction** and ultimately CHF. [1] *Eisenmenger syndrome* - While a severe complication of an untreated large PDA, it represents a **late stage** where the left-to-right shunt has reversed due to **pulmonary hypertension**. [1] - It is not the *most common* initial complication, as CHF often develops earlier in the disease progression. *Infective endocarditis* - This is a potential long-term complication of a PDA, especially if untreated, due to the **turbulent blood flow** across the ductus. - However, it is less common than CHF, which results directly from the hemodynamic burden imposed by a large shunt. *None of the options* - This option is incorrect because **Congestive Heart Failure** is indeed a very common and significant complication of a large Patent Ductus Arteriosus.
Question 95: What is the daily temperature variation in remittent fever?
- A. < 0.5 °C
- B. > 1.0 °C (Correct Answer)
- C. < 1.0 °C
- D. > 2.0 °C
Explanation: ***> 1.0 °C*** - In **remittent fever**, the temperature fluctuates by **more than 1.0 °C** (or 2°F) over a 24-hour period. [1] - Despite the significant variation, the temperature **never returns to normal** during the day. [1] *< 0.5 °C* - A variation of less than 0.5 °C (or 1°F) is more characteristic of a **sustained or continuous fever**, where the temperature remains elevated with minimal fluctuation. [1] - This pattern is seen in conditions like **typhoid fever** or **pneumonia**. *< 1.0 °C* - While reflecting some fluctuation, a variation of less than 1.0 °C is not sufficient to classify a fever as remittent. - Remittent fever specifically requires a **larger daily swing** in temperature. *> 2.0 °C* - While a variation greater than 2.0 °C would certainly fall under the definition of remittent fever (as it's > 1.0 °C), the defining lower limit for remittent fever is typically **> 1.0 °C (or 2°F)**. - A larger fluctuation might occur, but > 1.0 °C is the minimum threshold.
Question 96: Which biomarker is typically elevated in the plasma of patients with chronic heart disease?
- A. Endothelin-1
- B. Troponin T
- C. B-type natriuretic peptide (BNP) (Correct Answer)
- D. Cortisol
Explanation: ***B-type natriuretic peptide (BNP)*** - **BNP** is a hormone secreted by **ventricular cardiomyocytes** in response to increased wall stretch and pressure overload, making it a strong indicator of **myocardial stress** and **chronic heart failure** [1]. - Elevated levels correlate with the **severity of heart failure**, aiding in diagnosis and prognosis [1]. *Endothelin-1* - **Endothelin-1** is a potent **vasoconstrictor** involved in vascular tone regulation and endothelial dysfunction. - While it can be elevated in conditions like **pulmonary hypertension** and **atherosclerosis**, it is not a primary diagnostic biomarker for chronic heart disease in general. *Troponin T* - **Troponin T** is a cardiac-specific protein that is released into the bloodstream following **myocardial injury or necrosis**. - While it is a crucial biomarker for **acute coronary syndromes** (e.g., heart attack), persistently elevated levels are not typical for stable chronic heart disease unless there is ongoing subclinical myocardial damage. *Cortisol* - **Cortisol** is a **stress hormone** produced by the adrenal glands, involved in metabolism, immune response, and blood pressure regulation. - While chronic stress can impact cardiovascular health, cortisol itself is not a specific diagnostic biomarker for chronic heart disease.
Question 97: A person experiences asthma attacks more than twice during the day and at least once during the night. What is the most likely classification of their asthma?
- A. Intermittent asthma
- B. Mild persistent asthma
- C. Moderate persistent asthma
- D. Severe persistent asthma (Correct Answer)
Explanation: ***Severe persistent asthma*** - This classification is characterized by **frequent symptoms**, specifically asthma attacks occurring more than twice daily and at least once nightly. - Individuals with severe persistent asthma often experience significant limitations in their daily activities and may have a **FEV1 (forced expiratory volume in 1 second)** less than 60% of predicted. *Intermittent asthma* - This classification is characterized by symptoms occurring less than two days per week and **nighttime awakenings less than two times per month**. - Symptoms are generally well-controlled with a short-acting beta-agonist (SABA) as needed. *Mild persistent asthma* - Patients with mild persistent asthma typically experience symptoms more than twice a week but **less than once a day**, and **nighttime awakenings 3-4 times per month**. - Their lung function (FEV1) is usually 80% or more of predicted. *Moderate persistent asthma* - This category involves daily symptoms and **nighttime awakenings more than once per week but not nightly**. - Lung function (FEV1) in moderate persistent asthma typically falls between 60% and 80% of predicted.
Question 98: Which of the following is a renal-specific nephropathy associated with HIV?
- A. Focal Segmental Glomerulosclerosis (FSGS) (Correct Answer)
- B. Mesangioproliferative Glomerulonephritis
- C. Membranous Nephropathy
- D. Membranoproliferative Glomerulonephritis (MPGN)
Explanation: ### Focal Segmental Glomerulosclerosis - It is a common renal complication associated with **HIV infection**, characterized by **podocyte injury** and segmental sclerosis [1]. - Often results in **nephrotic syndrome**, presenting with significant **proteinuria** and edema, making it distinct in HIV renal pathology [1]. ### Membranous Glomerulonephritis - Typically presents with **subepithelial immune complex deposits**, leading to a different pathophysiological mechanism. - More commonly associated with other secondary causes, such as **drugs** or **infection**, rather than being specific to HIV. ### Mesangioproliferative Glomerulonephritis - Characterized by **mesangial cell proliferation and immune complex deposition**, often linked with various infections but not specifically with HIV. - Usually shows **hematuria** and mild proteinuria, lacking the severe nephrotic syndrome seen in focal segmental glomerulosclerosis. ### Membranoproliferative Glomerulonephritis - Features **proliferation of mesangial and endothelial cells**, leading to a distinctive pattern on renal biopsy, not specific to HIV. - Typically presents in other contexts such as **chronic infections** or **autoimmune diseases**, rather than predominantly with HIV.
Question 99: Which of the following is a characteristic of Wilson's disease?
- A. Increased copper in liver (Correct Answer)
- B. Autosomal dominant
- C. Increased serum ceruloplasmin
- D. Decreased copper excretion in urine
Explanation: ***Increased copper in liver*** - Wilson's disease is characterized by **accumulation of copper** in liver tissues due to defective copper transport [1]. - This excess leads to **hepatocellular damage**, resulting in liver dysfunction and potential cirrhosis [1]. *Decreased copper excretion in urine* - In Wilson's disease, there is actually **decreased excretion of copper**, which results in accumulation in the liver [1]. - **Urine copper levels** are typically low to normal in early stages because the liver fails to excrete excess copper effectively. *Autosomal dominant* - Wilson's disease is inherited in an **autosomal recessive** pattern, not dominant. - It is caused by mutations in the gene responsible for copper transport (ATP7B) [1]. *Increased serum ceruloplasmin* - Serum ceruloplasmin levels are often **decreased** in Wilson's disease due to impaired copper incorporation into this protein [1]. - Low ceruloplasmin is a key laboratory finding, contrasting the assertion of this option.
Question 100: The most common cause of pontine hemorrhage is
- A. Hypertension (Correct Answer)
- B. Diabetes
- C. Trauma
- D. Aneurysmal rupture
Explanation: Hypertension - **Chronic hypertension** leads to the weakening and rupture of small perforating arteries in the pons, making it the most common cause of **pontine hemorrhage** [1]. - The elevated pressure damages the **endothelium** and smooth muscle layers of these vessels, predisposing them to bleeding. *Diabetes* - While diabetes can cause microvascular complications, it is not considered the most common cause of **pontine hemorrhage**. - Its primary cerebral vascular complications include increased risk of **ischemic stroke** rather than hemorrhagic stroke in the pons. *Trauma* - **Traumatic brain injury** can cause various types of intracranial hemorrhage, but isolated **pontine hemorrhage** directly due to trauma is less common than that due to hypertension [1]. - Trauma typically results in contusions, subdural, or epidural hematomas, often in superficial brain regions. *Aneurysmal rupture* - **Aneurysmal rupture** is a common cause of subarachnoid hemorrhage, particularly from the Circle of Willis, but pontine hemorrhages are rarely caused by aneurysms within the pons itself [1]. - The vessels supplying the pons are typically small and perforating, not commonly forming dissecting or saccular aneurysms.