Biochemistry
1 questionsWhich organelle is primarily affected in Fabry's disease?
NEET-PG 2012 - Biochemistry NEET-PG Practice Questions and MCQs
Question 1061: Which organelle is primarily affected in Fabry's disease?
- A. Endoplasmic Reticulum
- B. Lysosome (Correct Answer)
- C. Golgi apparatus
- D. Cell membrane
Explanation: ***Lysosome*** - Fabry's disease is a **lysosomal storage disorder** caused by a deficiency of the enzyme **alpha-galactosidase A**. - This enzyme deficiency leads to the accumulation of **globotriaosylceramide (Gb3)** within lysosomes in various cells throughout the body. *Endoplasmic Reticulum* - The **endoplasmic reticulum** is involved in protein synthesis and folding, and lipid metabolism. - While cellular stress from Gb3 accumulation can indirectly affect the ER, it is not the primary organelle involved in the storage of the accumulated substrate in Fabry's disease. *Golgi apparatus* - The **Golgi apparatus** modifies, sorts, and packages proteins and lipids. - It is not the site of primary pathology or substrate accumulation in lysosomal storage diseases. *Cell membrane* - The **cell membrane** regulates passage of substances into and out of the cell. - While lysosomal dysfunction can ultimately impact overall cell function, the cell membrane itself is not the organelle where the undigested substrate accumulates in Fabry's disease.
Dermatology
1 questionsMuir–Torre syndrome shows
NEET-PG 2012 - Dermatology NEET-PG Practice Questions and MCQs
Question 1061: Muir–Torre syndrome shows
- A. Sebaceous gland tumors (Correct Answer)
- B. Intestinal polyps
- C. Lisch nodules
- D. Hyperelastic joints
Explanation: ***Sebaceous gland tumors*** - **Muir-Torre syndrome** is a genetic condition characterized by the presence of at least one **sebaceous gland tumor** (adenoma, epithelioma, or carcinoma) and at least one internal malignancy. - It is considered a variant of **Lynch syndrome (hereditary nonpolyposis colorectal cancer - HNPCC)**, stemming from germline mutations in **DNA mismatch repair genes**. *Intestinal polyps (associated with familial adenomatous polyposis)* - While Lynch syndrome (to which Muir-Torre is related) does involve an increased risk of colorectal cancer, **multiple intestinal polyps** are the hallmark of **Familial Adenomatous Polyposis (FAP)**. - FAP is caused by a mutation in the **APC gene**, distinct from the mismatch repair gene mutations seen in Muir-Torre syndrome. *Lisch nodules (associated with Neurofibromatosis type 1)* - **Lisch nodules** are benign **iris hamartomas** typically found in patients with **Neurofibromatosis type 1 (NF1)**. - NF1 is a neurocutaneous disorder caused by a mutation in the **NF1 gene**, presenting with café-au-lait spots, neurofibromas, and optic gliomas, which are unrelated to Muir-Torre syndrome. *Hyperelastic joints (associated with Ehlers-Danlos syndrome)* - **Hyperelasticity of joints** and skin is a characteristic feature of **Ehlers-Danlos syndrome (EDS)**, a group of heritable disorders affecting connective tissue. - EDS is caused by defects in **collagen synthesis or processing**, and its clinical manifestations are distinct from the mucocutaneous and internal malignancies seen in Muir-Torre syndrome.
Internal Medicine
3 questionsEsophageal manometry is useful in diagnosing all of the following conditions EXCEPT:
Which of the following statements is MOST accurate regarding herpes encephalitis?
What is the most characteristic cerebrospinal fluid (CSF) finding in viral meningitis?
NEET-PG 2012 - Internal Medicine NEET-PG Practice Questions and MCQs
Question 1061: Esophageal manometry is useful in diagnosing all of the following conditions EXCEPT:
- A. Achalasia (a motility disorder)
- B. Diffuse esophageal spasm (a motility disorder)
- C. Malignancy (not typically diagnosed with this test) (Correct Answer)
- D. Assessment of esophageal motility prior to surgery for GERD
Explanation: ***Malignancy (not typically diagnosed with this test)*** - **Esophageal manometry** evaluates the **motor function** of the esophagus, measuring pressure changes during swallowing. - **Malignancy**, such as esophageal cancer, is primarily diagnosed with **endoscopy with biopsy** and imaging studies, not by assessing motility. *Achalasia (a motility disorder)* - **Esophageal manometry** is the **gold standard** for diagnosing achalasia, characterized by **absent peristalsis** in the esophageal body and **incomplete relaxation of the lower esophageal sphincter (LES)** [1]. - High-resolution manometry shows elevated **integrated relaxation pressure (IRP)** and often pan-esophageal pressurization. *Diffuse esophageal spasm (a motility disorder)* - This condition is also diagnosed by **esophageal manometry**, which reveals simultaneous, **non-peristaltic contractions** of high amplitude, often interspersed with normal peristalsis [1]. - It may also show **premature contractions** and **multiple rapid swallows** triggering spasm. *Assessment of esophageal motility prior to surgery for GERD* - **Manometry** is routinely performed before **anti-reflux surgery (e.g., Nissen fundoplication)** to rule out underlying esophageal motility disorders that could complicate surgery or worsen symptoms post-operatively [1]. - Identifying conditions like **achalasia** or **scleroderma** would contraindicate a standard fundoplication, as dysphagia could worsen [1].
Question 1062: Which of the following statements is MOST accurate regarding herpes encephalitis?
- A. Focal neurological symptoms are common.
- B. EEG findings are nonspecific and not diagnostic.
- C. The temporal lobe is commonly involved. (Correct Answer)
- D. MRI is a key diagnostic tool.
Explanation: ***The temporal lobe is commonly involved.*** - **Herpes simplex encephalitis (HSE)** characteristically targets the **temporal lobes** [1] and **orbitofrontal cortex**, leading to specific neurological deficits. - This predilection for the temporal lobes often results in symptoms such as **aphasia**, **seizures**, and **memory disturbances** [1]. *Focal neurological symptoms are common.* - While focal neurological symptoms such as **aphasia**, **hemiparesis**, and **seizures** are indeed common in HSE [1], this statement is less specific than the involvement of the temporal lobe. - The **localization** of the infection to the temporal lobes explains why these focal symptoms are so prevalent [1]. *MRI is a key diagnostic tool.* - **MRI findings**, particularly **T2-weighted** and **FLAIR sequences**, showing **edema** and **hemorrhage** in the temporal lobes and insular cortex, are highly suggestive of HSE. - However, the most definitive diagnostic tool remains the detection of **HSV DNA** in the **cerebrospinal fluid (CSF)** via **PCR**. *EEG findings are nonspecific and not diagnostic.* - **EEG** in HSE often shows **periodic lateralizing epileptiform discharges (PLEDs)** or **focal slowing** primarily over the temporal lobes, which are highly suggestive, although not entirely diagnostic on their own. - These findings can help guide further investigation and support a clinical diagnosis in conjunction with other tests.
Question 1063: What is the most characteristic cerebrospinal fluid (CSF) finding in viral meningitis?
- A. Lymphocytic pleocytosis in CSF (Correct Answer)
- B. WBC count typically less than 1000/mL
- C. Glucose levels normal or slightly decreased
- D. Protein levels normal or slightly increased
Explanation: ***Lymphocytic pleocytosis in CSF*** - **Lymphocytic pleocytosis**, meaning an increase in lymphocytes in the CSF, is the hallmark of **viral meningitis**, reflecting the immune response to the viral pathogen. [1] - While other CSF parameters can be altered, the presence of predominantly lymphocytes is the most reliable distinguishing feature from bacterial meningitis. [1] *WBC count typically less than 1000/mL* - This statement is generally true for viral meningitis, as the **WBC count** is usually lower than in bacterial meningitis. - However, it is not the *most characteristic* finding because bacterial meningitis can sometimes present with a WBC count under 1000/mL, especially early in the disease, and the *predominance* of lymphocytes is more specific to viral infection. *Glucose levels normal or slightly decreased* - **Normal glucose levels** are typical in viral meningitis, but they can be slightly decreased in a minority of cases. - This finding is not as characteristic as lymphocytic pleocytosis because significantly decreased glucose levels are more indicative of **bacterial or fungal meningitis**. *Protein levels normal or slightly increased* - **Protein levels** in viral meningitis are often normal or mildly elevated, usually not exceeding **100-150 mg/dL**. - While consistent with viral meningitis, this finding is less specific than lymphocytic pleocytosis, as protein levels can also be elevated in other conditions, including early bacterial meningitis.
Pathology
1 questionsThe immunoglobulin most commonly involved in Multiple Myeloma is:
NEET-PG 2012 - Pathology NEET-PG Practice Questions and MCQs
Question 1061: The immunoglobulin most commonly involved in Multiple Myeloma is:
- A. IgG (Correct Answer)
- B. IgM
- C. IgA
- D. IgD
Explanation: ***IgG*** - In Multiple Myeloma, the most commonly involved immunoglobulin is **IgG**, which is often produced in excess by malignant plasma cells [1][2]. - The presence of **monoclonal IgG** in serum is a key indicator of this malignancy, evident in diagnostic tests like serum protein electrophoresis. *IgM* - While **elevated IgM** levels can occur in other conditions like Waldenström's macroglobulinemia, it is not typically associated with Multiple Myeloma [2]. - IgM is produced by a different type of plasma cell and does not reflect the classic presentation of Multiple Myeloma. *IgA* - Although **IgA** can be involved in some cases of Multiple Myeloma, it is much less common than IgG [1][2]. - Patients with predominately **IgA Multiple Myeloma** are relatively rare compared to those with IgG. *IgD* - **IgD** myeloma is a very rare type of Multiple Myeloma, accounting for less than 2% of cases [1][2]. - It is not typically associated with the classic symptoms and conditions that characterize the more common IgG or IgA forms. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Diseases of White Blood Cells, Lymph Nodes, Spleen, and Thymus, pp. 608-609. [2] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Blood And Bone Marrow Disease, pp. 616-617.
Physiology
1 questionsTetany is seen in
NEET-PG 2012 - Physiology NEET-PG Practice Questions and MCQs
Question 1061: Tetany is seen in
- A. Respiratory alkalosis (Correct Answer)
- B. Respiratory acidosis
- C. Metabolic acidosis
- D. Hyperkalemia
Explanation: ***Respiratory alkalosis*** - **Respiratory alkalosis** is caused by **hyperventilation**, which leads to a decrease in arterial partial pressure of carbon dioxide (**PaCO2**). - This decrease in PaCO2 causes an increase in pH (alkalemia) and a shift in the albumin-bound calcium equilibrium, reducing the amount of **ionized calcium** in the blood, leading to symptoms of **hypocalcemia** such as tetany. *Respiratory acidosis* - **Respiratory acidosis** is characterized by an increase in PaCO2 and a decrease in pH due to inadequate ventilation, which would not typically cause tetany. - In fact, the acidosis would tend to increase **ionized calcium** levels, thereby counteracting any tendency towards symptoms of hypocalcemia. *Metabolic acidosis* - **Metabolic acidosis** involves a decrease in bicarbonate concentration and pH, often due to conditions like diabetic ketoacidosis or lactic acidosis. - Similar to respiratory acidosis, the acidic environment of **metabolic acidosis** tends to increase **ionized calcium** levels, making tetany unlikely. *Hyperkalemia* - **Hyperkalemia** refers to elevated potassium levels in the blood, which primarily affects cardiac and neuromuscular function. - While it can cause muscle weakness and cardiac arrhythmias, it does not directly lead to **tetany**, which is a sign of **hypocalcemia**.
Radiology
1 questionsStep ladder pattern of gas shadow is seen in
NEET-PG 2012 - Radiology NEET-PG Practice Questions and MCQs
Question 1061: Step ladder pattern of gas shadow is seen in
- A. Intestinal obstruction (Correct Answer)
- B. Gastric outlet obstruction
- C. Duodenal obstruction
- D. Sigmoid volvulus
Explanation: ***Intestinal obstruction*** - A **step-ladder pattern** of gas shadows is a classic radiological sign seen in **small bowel obstruction** due to dilated, fluid-filled loops of small bowel stacked on top of each other. - This pattern results from the accumulation of gas and fluid proximal to the obstruction, causing dilated bowel loops to arrange horizontally. *Gastric outlet obstruction* - This condition primarily results in a **dilated stomach** with fluid and gas, not typically a step-ladder pattern in the small bowel. - Vomiting is usually a prominent symptom, and imaging would show a large fluid-filled stomach. *Duodenal obstruction* - Causes dilatation of the stomach and duodenum, leading to a "**double-bubble sign**" (dilated stomach and proximal duodenum). - It does not typically produce the extensive, stacked small bowel loops seen in a step-ladder pattern. *Sigmoid volvulus* - Characterized by a distinctive large, dilated loop of sigmoid colon, often described as a "**coffee bean sign**" or an **inverted U-shape**. - This is a large bowel obstruction and does not typically present with a step-ladder pattern of small bowel gas.
Surgery
2 questionsWhat type of burn is characterized by flash burn, tenderness, redness, and pain?
Road traffic accident (RTA) with multiple fractures - initial treatment would be:
NEET-PG 2012 - Surgery NEET-PG Practice Questions and MCQs
Question 1061: What type of burn is characterized by flash burn, tenderness, redness, and pain?
- A. Scalded burn
- B. First degree burn (Correct Answer)
- C. Second degree burn
- D. Fourth degree burn
Explanation: ***First degree burn*** - Characterized by **tenderness**, **redness**, and **pain** without blistering. - Involves only the **epidermis**, typically from a **flash burn** or brief contact with a hot object. *Scalded burn* - A type of burn caused by **hot liquid or steam**, not a characteristic of a specific burn depth. - Can be superficial or deep, depending on the **temperature** and **duration of exposure**. *Second degree burn* - Involves the **epidermis and dermis**, presenting with **blisters**, severe pain, and sometimes a wet, weeping appearance. - Often heals with scarring, unlike first-degree burns. *Fourth degree burn* - The most severe type of burn, extending through **all layers of skin** into underlying **muscle**, **tendons**, or **bone**. - Often appears charred or black, and victims may feel little pain due to extensive nerve damage.
Question 1062: Road traffic accident (RTA) with multiple fractures - initial treatment would be:
- A. Management of shock
- B. Splinting of limbs
- C. Airway management (Correct Answer)
- D. Cervical spine protection
Explanation: ***Airway management*** - In trauma, **establishing and maintaining a patent airway** is the absolute priority, as compromised breathing can lead to rapid deterioration and death. - The **ABCs (Airway, Breathing, Circulation)** of trauma care dictate that airway intervention precedes other life-saving measures. *Management of shock* - While crucial, **managing shock (C)** follows **airway (A)** and **breathing (B)** in the primary survey of trauma care. - Addressing profound shock without a patent airway can be ineffective and leads to irreversible damage. *Splinting of limbs* - **Splinting fractures** is important for pain control, preventing further injury, and minimizing blood loss in open fractures, but it is not an immediate life-saving intervention. - This falls under the **secondary survey** or definitive management, after life-threatening issues have been addressed. *Cervical spine protection* - **Cervical spine protection** is essential in trauma to prevent further neurological injury and is performed simultaneously with airway management (often with in-line stabilization). - However, a patent airway is the **most immediate life-sustaining intervention** if the airway is compromised.