Biochemistry
1 questionsDiagnosis of carcinoid tumour is done by urinary estimation of:
NEET-PG 2012 - Biochemistry NEET-PG Practice Questions and MCQs
Question 901: Diagnosis of carcinoid tumour is done by urinary estimation of:
- A. VMA
- B. Metanephrines
- C. Catecholamines
- D. 5HIAA (Correct Answer)
Explanation: ***5HIAA*** - The urinary estimate of **5-hydroxyindoleacetic acid (5HIAA)** is the primary diagnostic test for **carcinoid tumors** [1], particularly those secreting serotonin. - Elevated levels of **5HIAA** in urine indicate excessive serotonin production, which is characteristic of these tumors. *VMA* - **Vanillylmandelic acid (VMA)** is a metabolite of catecholamines and is primarily used in diagnosing **neuroblastoma** or **pheochromocytoma**, not carcinoid tumors. - Although it indicates catecholamine secretion, it does not correlate with **serotonin** levels associated with carcinoid tumors. *Metanephrines* - **Metanephrines** represent metabolites of catecholamines and are mainly evaluated for **pheochromocytoma**. - They do not provide information on serotonin metabolism or carcinoid tumor activity. *Catecholamines* - Catecholamines such as **epinephrine and norepinephrine** are not specifically related to carcinoid tumors and often indicate other neuroendocrine tumors. - Their levels do not correlate with serotonin or its metabolite, **5HIAA**, used for carcinoid diagnosis. **References:** [1] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. (Basic Pathology) introduces the student to key general principles of pathology, both as a medical science and as a clinical activity with a vital role in patient care. Part 2 (Disease Mechanisms) provides fundamental knowledge about the cellular and molecular processes involved in diseases, providing the rationale for their treatment. Part 3 (Systematic Pathology) deals in detail with specific diseases, with emphasis on the clinically important aspects., pp. 12-15.
Dermatology
2 questionsRichner-Hanhart syndrome is characterized by which of the following?
The appearance described as an inverted champagne bottle is associated with which condition?
NEET-PG 2012 - Dermatology NEET-PG Practice Questions and MCQs
Question 901: Richner-Hanhart syndrome is characterized by which of the following?
- A. Autosomal dominant
- B. Associated with abnormality in lipid metabolism
- C. Ocular and cutaneous features (Correct Answer)
- D. Never associated with neurological involvement
Explanation: ***Ocular and cutaneous features*** - **Richner-Hanhart syndrome**, also known as **Tyrosinemia type II**, is characterized by the classic triad of **painful hyperkeratotic plaques** on the palms and soles (cutaneous features), **corneal ulcers** or **dendritic keratitis** (ocular features), and **variable neurological involvement**. - These features arise from the accumulation of **tyrosine** due to a deficiency of the enzyme **hepatic tyrosine aminotransferase (TAT)**. - The **ocular and cutaneous manifestations** are the hallmark features that define this syndrome. *Autosomal dominant* - Richner-Hanhart syndrome is inherited in an **autosomal recessive** pattern, meaning two copies of the defective gene (TAT gene on chromosome 16) are required for the condition to manifest. - An **autosomal dominant** inheritance pattern would mean only one copy of the defective gene is sufficient to cause the disorder. *Associated with abnormality in lipid metabolism* - The syndrome is an inborn error of **amino acid metabolism**, specifically involving **tyrosine**, not lipid metabolism. - Diseases associated with abnormality in **lipid metabolism** include conditions like Gaucher disease, Niemann-Pick disease, or Fabry disease. *Never associated with neurological involvement* - This is **incorrect**. **Neurological involvement** including intellectual disability, developmental delay, seizures, and behavioral problems occurs in **30-50% of cases**. - The accumulation of **tyrosine** and its metabolites (particularly tyrosine crystals) can be **neurotoxic**, leading to varying degrees of neurological impairment. - Early dietary restriction of tyrosine and phenylalanine can prevent or minimize neurological complications.
Question 902: The appearance described as an inverted champagne bottle is associated with which condition?
- A. Varicose veins
- B. Deep vein thrombosis
- C. Venous ulceration
- D. Lipodermatosclerosis (Correct Answer)
Explanation: ***Lipodermatosclerosis*** - This condition presents with a characteristic "inverted champagne bottle" appearance, where the **ankle area is narrow** and the **calf area above it is wider** due to fibrotic changes and fat atrophy. - It's a severe manifestation of **chronic venous insufficiency**, characterized by **skin hardening**, pigmentation, and inflammation, often preceding venous ulceration. *Varicose veins (enlarged, twisted veins)* - While associated with **venous insufficiency**, varicose veins themselves are **dilated, tortuous superficial veins**, and do not typically cause the generalized lower leg shape change described. - They may cause swelling and discomfort but do not directly lead to the **fibrotic narrowing** seen in an "inverted champagne bottle" leg. *Deep vein thrombosis (DVT) (acute venous obstruction)* - DVT is an **acute condition** involving a **blood clot in a deep vein**, leading to sudden onset pain, swelling, and redness. - It does not cause the **chronic skin changes** and **fibrotic reshaping** of the calf and ankle that characterize lipodermatosclerosis. *Venous ulceration (open sores due to venous insufficiency)* - Venous ulcers are **open sores** that occur in severe chronic venous insufficiency, often found above the medial malleolus. - While they are a complication of the underlying venous disease that can also cause lipodermatosclerosis, the ulceration itself is a **skin lesion**, not the **overall inverted champagne bottle shape** of the leg.
Internal Medicine
2 questionsWhat is the initial treatment of choice for managing secondary hyperparathyroidism in patients with renal osteodystrophy?
In which of the following conditions is hypomagnesemia not typically observed?
NEET-PG 2012 - Internal Medicine NEET-PG Practice Questions and MCQs
Question 901: What is the initial treatment of choice for managing secondary hyperparathyroidism in patients with renal osteodystrophy?
- A. Cinacalcet
- B. Bisphosphonates
- C. Calcium restriction
- D. Phosphate binders (Correct Answer)
Explanation: ***Phosphate binders*** - **Phosphate binders** are the initial treatment because **hyperphosphatemia** is the primary driver of secondary hyperparathyroidism in renal disease, triggering parathyroid hormone (PTH) release [1]. - They work by binding dietary phosphate in the gastrointestinal tract, preventing its absorption and thus lowering serum phosphate levels [1]. *Cinacalcet* - **Cinacalcet** is a calcimimetic that increases the sensitivity of calcium-sensing receptors on the parathyroid gland, reducing **PTH secretion** [1]. - It is often used if **phosphate binders** and **vitamin D analogs** are insufficient in controlling PTH, making it a second-line treatment [1]. *Bisphosphonates* - **Bisphosphonates** are used to treat osteoporosis by inhibiting osteoclast activity and reducing bone resorption. - They are generally contraindicated in advanced renal osteodystrophy due to concerns about adynamic bone disease and are not an initial treatment for **secondary hyperparathyroidism**. *Calcium restriction* - While restricting dietary calcium might seem intuitive, **hypocalcemia** is often a problem in renal disease due to impaired vitamin D activation [1]. - Overly restricting calcium can worsen hypocalcemia, which would further stimulate PTH release, thus it is not an initial treatment for **secondary hyperparathyroidism**.
Question 902: In which of the following conditions is hypomagnesemia not typically observed?
- A. Diarrhea
- B. Gitelman syndrome
- C. Diabetes mellitus (Correct Answer)
- D. Bartter syndrome
Explanation: Diabetes mellitus - While hypomagnesemia can occur in poorly controlled diabetes due to osmotic diuresis, it is not a typical or defining feature of the condition itself in the same way as other options. - Many individuals with controlled diabetes may have normal magnesium levels, and it's often associated with complications rather than the primary disease process. Diarrhea - Chronic or severe diarrhea leads to significant gastrointestinal losses of electrolytes, including magnesium. - This is a common cause of hypomagnesemia, as the body loses fluids and minerals before they can be absorbed. Gitelman syndrome - This is a renal tubular disorder characterized by a defect in the thiazide-sensitive Na-Cl cotransporter in the distal convoluted tubule. - It leads to hypomagnesemia (due to increased renal excretion) and hypokalemia, along with metabolic alkalosis. Bartter syndrome - This syndrome involves a defect in the Na-K-2Cl cotransporter in the thick ascending limb of the loop of Henle. - It results in significant renal wasting of magnesium [1], leading to hypomagnesemia, along with hypokalemia and metabolic alkalosis.
Ophthalmology
1 questionsWhat is a potential ocular complication caused by alkali exposure?
NEET-PG 2012 - Ophthalmology NEET-PG Practice Questions and MCQs
Question 901: What is a potential ocular complication caused by alkali exposure?
- A. Symblepharon (Correct Answer)
- B. Papilloedema
- C. Optic neuritis
- D. Retinal detachment
Explanation: ***Symblepharon*** - **Symblepharon** is the **adhesion of the palpebral conjunctiva to the bulbar conjunctiva**. It is a common long-term complication of severe alkali burns to the eye, reflecting significant tissue damage and cicatrization. - Alkali causes **liquefactive necrosis**, deeply penetrating ocular tissues and leading to extensive inflammation, scarring, and subsequent adhesion formation due to the destruction of the conjunctival surface. *Papilloedema* - **Papilloedema** refers to **optic disc swelling due to increased intracranial pressure**, not a direct result of ocular surface trauma or chemical exposure. - While systemic conditions can cause papilloedema, it is unrelated to the local effects of an **alkali burn**. *Optic neuritis* - **Optic neuritis** is an **inflammation of the optic nerve**, often associated with demyelinating diseases like multiple sclerosis. - It results in **vision loss** and pain with eye movement but is not a complication of external ocular chemical burns. *Retinal detachment* - **Retinal detachment** occurs when the **retina separates from the underlying retinal pigment epithelium**, leading to significant vision loss. - This condition is typically caused by trauma, vitreous traction, or retinal tears, and is not a direct consequence of an **alkali burn to the anterior segment of the eye**.
Pediatrics
1 questionsA child presents with recurrent pulmonary infections and hemoptysis due to associated bronchiectasis. Imaging shows unilateral loss of lung volume with hyperlucency on chest radiograph and reduced vascularity on CT scan of the chest. The abdominal organs are normally placed. What is the most likely cause?
NEET-PG 2012 - Pediatrics NEET-PG Practice Questions and MCQs
Question 901: A child presents with recurrent pulmonary infections and hemoptysis due to associated bronchiectasis. Imaging shows unilateral loss of lung volume with hyperlucency on chest radiograph and reduced vascularity on CT scan of the chest. The abdominal organs are normally placed. What is the most likely cause?
- A. Swyer-James-MacLeod syndrome (Correct Answer)
- B. Immotile cilia syndrome
- C. Kartagener syndrome
- D. Mendelson syndrome
Explanation: ***Swyer-James-MacLeod syndrome*** - This syndrome presents with **unilateral hyperlucent lung**, reduced vascularity, and bronchiectasis, often following a severe childhood respiratory infection, leading to air trapping and recurrent infections. - The imaging findings of **unilateral loss of lung volume**, hyperlucency, and reduced vascularity are classic for Swyer-James-MacLeod syndrome, which is also known as unilateral emphysema. *Immotile cilia syndrome* - This is a broader term that encompasses conditions like Kartagener syndrome, characterized by ciliary dysfunction leading to **recurrent sinopulmonary infections**; however, it does not typically present with unilateral hyperlucent lung or reduced vascularity. - While it causes bronchiectasis, the specific imaging findings described (unilateral hyperlucency) are not characteristic of isolated immotile cilia syndrome. *Kartagener syndrome* - This is a subgroup of primary ciliary dyskinesia that includes the classic triad of **situs inversus**, bronchiectasis, and sinusitis. The patient in the prompt has normally placed abdominal organs, ruling out situs inversus. - Although it involves recurrent pulmonary infections and bronchiectasis, the presence of **normally placed abdominal organs** and unilateral hyperlucency on imaging makes Kartagener syndrome less likely. *Mendelson syndrome* - This refers to **chemical pneumonitis** caused by the aspiration of gastric contents, typically during anesthesia or in patients with impaired consciousness. - It presents acutely with respiratory distress, hypoxemia, and diffuse infiltrates on imaging, which is inconsistent with the chronic presentation of recurrent infections and unilateral hyperlucency described.
Pharmacology
1 questionsWhat is the drug of choice for listeria meningitis?
NEET-PG 2012 - Pharmacology NEET-PG Practice Questions and MCQs
Question 901: What is the drug of choice for listeria meningitis?
- A. Ampicillin (Correct Answer)
- B. Cefotaxime
- C. Ciprofloxacin
- D. Ceftriaxone
Explanation: ***Ampicillin*** - **Ampicillin** is the **drug of choice** for *Listeria monocytogenes* meningitis due to its excellent in vitro activity and good central nervous system penetration. - It is often used in combination with an **aminoglycoside** (e.g., gentamicin) for synergistic bactericidal activity, especially in severe cases, though gentamicin does not penetrate the CSF well. *Cefotaxime* - **Third-generation cephalosporins** like cefotaxime have poor activity against *Listeria monocytogenes* due to the organism's intrinsic resistance to these agents. - While effective against many other bacterial causes of meningitis (e.g., *S. pneumoniae*, *N. meningitidis*), it is not appropriate for *Listeria*. *Ceftriaxone* - Similar to cefotaxime, **ceftriaxone** is a third-generation cephalosporin and is **ineffective** against *Listeria monocytogenes* due to the lack of penicillin-binding protein (PBP) affinity. - Its use for *Listeria* meningitis would lead to treatment failure. *Ciprofloxacin* - **Ciprofloxacin**, a fluoroquinolone, is generally **not recommended** as a first-line treatment for *Listeria* meningitis, despite some in vitro activity. - Its use is typically reserved for patients with severe allergies to penicillins, and even then, **trimethoprim-sulfamethoxazole** is usually preferred as an alternative to ampicillin.
Surgery
2 questionsA 10 cm tumor is found on the anterior surface of the thigh. What is the most appropriate procedure to obtain a diagnosis?
Which of the following is a common consequence of gastrectomy?
NEET-PG 2012 - Surgery NEET-PG Practice Questions and MCQs
Question 901: A 10 cm tumor is found on the anterior surface of the thigh. What is the most appropriate procedure to obtain a diagnosis?
- A. Incision biopsy (Correct Answer)
- B. Excision biopsy
- C. FNAC
- D. USG
Explanation: ***Incision biopsy*** - An **incision biopsy** is most appropriate for a large tumor (10 cm) to obtain a tissue diagnosis without performing a potentially morbid or disfiguring complete excision upfront. - It involves removing a representative section of the tumor for histopathological analysis, providing adequate tissue for diagnosis, grading, and subtyping. - This allows definitive treatment planning based on confirmed histopathology. *Excision biopsy* - **Excision biopsy** is generally reserved for smaller tumors (typically <3-5 cm) that can be completely resected with acceptable cosmetic and functional outcomes. - Excision of a 10 cm tumor on the thigh would be a significant surgical procedure, potentially causing substantial morbidity, without a prior definitive diagnosis. - Could compromise subsequent definitive surgery if margins are inadequate. *FNAC* - **FNAC (Fine Needle Aspiration Cytology)** provides only cytological diagnosis, which is insufficient for definitive diagnosis, grading, and subtyping of soft tissue tumors, especially sarcomas. - It misses crucial architectural features and tissue patterns needed for accurate classification. - May yield inadequate or non-diagnostic samples from large heterogeneous tumors. *USG* - **USG (Ultrasound)** is an imaging modality, not a tissue diagnosis procedure. - While useful for characterizing mass features (size, location, vascularity, solid vs cystic), it cannot provide histopathological diagnosis. - The question specifically asks for a procedure to "obtain a diagnosis," which requires tissue sampling for microscopic examination.
Question 902: Which of the following is a common consequence of gastrectomy?
- A. Calcium deficiency
- B. Iron deficiency (Correct Answer)
- C. Steatorrhoea
- D. Fluid loss
Explanation: ***Iron deficiency*** - Gastrectomy often leads to **achlorhydria** or hypochlorhydria, reducing the conversion of **ferric iron** (Fe3+) to its more absorbable ferrous form (Fe2+). - Additionally, bypassing the duodenum, a primary site of iron absorption, further contributes to **iron malabsorption**. *Calcium deficiency* - While gastrectomy can contribute to calcium malabsorption due to reduced gastric acidity and faster transit, **iron deficiency** is typically a more direct and common initial consequence. - **Vitamin D deficiency**, often co-occurring with gastrectomy, is a more direct cause of **calcium malabsorption**. *Steatorrhoea* - **Steatorrhoea** (fat malabsorption) is more commonly associated with conditions affecting the **pancreas** or **small intestine** (e.g., celiac disease, chronic pancreatitis) rather than primarily gastrectomy unless there is significant bile salt malabsorption or rapid gastric emptying affecting nutrient mixing. - Although rapid transit post-gastrectomy can sometimes impair fat digestion, it's not the most common direct consequence compared to iron deficiency. *Fluid loss* - **Fluid loss** is usually an acute post-surgical complication or related to conditions causing vomiting or diarrhea, and not a common long-term consequence of gastrectomy itself. - While **dumping syndrome** can occur after gastrectomy, causing osmotic fluid shifts into the intestine, generalized chronic fluid loss is not a primary recognized long-term sequela.