Biochemistry
1 questionsWhich of the following statements about Maple Syrup Urine Disease (MSUD) is true?
NEET-PG 2013 - Biochemistry NEET-PG Practice Questions and MCQs
Question 791: Which of the following statements about Maple Syrup Urine Disease (MSUD) is true?
- A. FeCl3 turns navy blue
- B. Asymptomatic
- C. Deficiency of branched chain amino acid enzymes (Correct Answer)
- D. Hyperaminoaciduria of aromatic amino acids
Explanation: ***Deficiency of branched chain amino acid enzymes*** - MSUD is caused by a deficiency in the **branched-chain alpha-keto acid dehydrogenase complex (BCKDC)**, an enzyme responsible for metabolizing **leucine, isoleucine, and valine**. - This enzyme deficiency leads to the accumulation of these **branched-chain amino acids (BCAAs)** and their corresponding branched-chain alpha-keto acids in the body. *Asymptomatic* - MSUD is a severe metabolic disorder that is **not asymptomatic**; it typically presents with distinct neurological and metabolic symptoms shortly after birth. - Clinical manifestations can include **poor feeding, lethargy, seizures**, and a characteristic **maple syrup odor** in urine and earwax. *FeCl3 turns navy blue* - The **ferric chloride test (FeCl3 test)** in MSUD typically yields a **green-gray or dark-green color** when testing for the accumulation of alpha-keto acids (specifically alpha-ketoisocaproic acid). - A **navy blue color** with FeCl3 is more characteristic of **alkaptonuria** due to the presence of homogentisic acid. *Hyperaminoaciduria of aromatic amino acids* - MSUD is characterized by the accumulation and excretion of **branched-chain amino acids (leucine, isoleucine, valine)** and their corresponding keto acids. - **Hyperaminoaciduria of aromatic amino acids** (e.g., phenylalanine, tyrosine, tryptophan) is seen in other conditions like **phenylketonuria (PKU)**, not MSUD.
Internal Medicine
8 questionsWhich of the following conditions is associated with megaloblastic anemia?
In inflammatory myopathy, which group of muscles is not affected
Which of the following is a feature of tumor lysis syndrome?
In which condition is the Albumin to Globulin (A:G) ratio maintained?
A 68-year-old patient presents with sudden onset of right-sided weakness and slurred speech. The symptoms completely resolve within 30 minutes with no residual neurological deficits. This clinical presentation is most consistent with:
Pea soup diarrhea is seen in -
Which of the following is not a treatment option for hypercalcemia?
Which of the following is commonly seen in Polycythemia Vera?
NEET-PG 2013 - Internal Medicine NEET-PG Practice Questions and MCQs
Question 791: Which of the following conditions is associated with megaloblastic anemia?
- A. Pernicious anemia (Correct Answer)
- B. Iron deficiency anemia
- C. Intestinal lymphatic ectasia
- D. Chronic kidney disease
Explanation: a and b - Megaloblastic anemia is commonly associated with **vitamin B12** [1] and **folate deficiencies** [2], which can occur due to various causes. - Conditions leading to malabsorption (such as those related to the gastrointestinal tract) contribute significantly to megaloblastic anemia [1, 2]. *ileal resection* - Ileal resection can indeed lead to **malabsorption** of vitamin B12 [1], particularly if the distal ileum is removed. - However, it is important to note that megaloblastic anemia specifically reflects a broader range of potential deficiencies, thus it is not an exclusive answer. *Crohn's disease* - Crohn's disease can cause **malabsorption** and result in vitamin B12 deficiency but is not a direct cause of megaloblastic anemia on its own. - The anemia may occur due to complications like **ileo-pouch anastomosis** rather than the disease itself. *Intestinal lymphatic ectasia* - This condition leads to **protein-losing enteropathy**, potentially causing deficiencies but not specifically leading to megaloblastic anemia. - The anemia associated with this condition is typically due to **hypoalbuminemia** and not a result of any vitamin deficiency directly.
Question 792: In inflammatory myopathy, which group of muscles is not affected
- A. Facial
- B. Proximal muscles of limb
- C. Ocular (Correct Answer)
- D. Distal muscles of limb
Explanation: ***Ocular*** - The **extraocular muscles** responsible for eye movement are generally spared in typical inflammatory myopathies, distinguishing them from other neuromuscular disorders. - Inflammatory myopathies primarily affect **skeletal muscles**, but **ocular muscles** have unique immunological and physiological properties that often protect them. *Facial* - While less commonly affected early in the disease, some inflammatory myopathies, particularly **dermatomyositis**, can eventually involve **facial muscles**, leading to weakness. - Involvement of **facial muscles** can manifest as difficulty with smiling, whistling, or closing the eyelids. *Proximal muscles of limb* - Inflammatory myopathies characteristically cause **proximal muscle weakness**, affecting muscles of the **shoulders, hips, and thighs** [1]. - This weakness often presents as difficulty climbing stairs, getting up from a chair, or lifting objects overhead [1]. *Distal muscles of limb* - While less common than proximal involvement, **distal muscle weakness** (affecting hands and feet) can occur in some subsets of inflammatory myopathies, such as **inclusion body myositis**. - This can lead to difficulties with fine motor tasks or foot drop.
Question 793: Which of the following is a feature of tumor lysis syndrome?
- A. Metabolic alkalosis (a rise in blood pH)
- B. Hypokalemia (a decrease in blood potassium levels)
- C. Hypocalcemia (a decrease in blood calcium levels) (Correct Answer)
- D. Hypophosphatemia (a decrease in blood phosphate levels)
Explanation: ***Hypocalcemia (a decrease in blood calcium levels)*** - **Hypocalcemia** in tumor lysis syndrome results from the precipitation of calcium with excessive phosphate released from lysed tumor cells. - The elevated phosphate levels bind to calcium, forming **calcium phosphate crystals** that can deposit in tissues, further lowering serum calcium. *Metabolic alkalosis (a rise in blood pH)* - Tumor lysis syndrome typically leads to **metabolic acidosis**, not alkalosis, due to the release of acidic intracellular metabolites like uric acid and phosphate. - The accumulation of these acidic compounds overwhelms the body's buffering systems, decreasing blood pH. *Hypokalemia (a decrease in blood potassium levels)* - Tumor lysis syndrome is characterized by **hyperkalemia**, an increase in blood potassium, as potassium is a major intracellular cation released during cell lysis. - The rapid breakdown of numerous tumor cells dumps vast amounts of intracellular potassium into the bloodstream. *Hypophosphatemia (a decrease in blood phosphate levels)* - Tumor lysis syndrome causes **hyperphosphatemia**, an elevation in blood phosphate levels, because phosphate is abundantly present within tumor cells and is released upon their destruction. - This excessive release of intracellular phosphate is a hallmark biochemical feature of the syndrome.
Question 794: In which condition is the Albumin to Globulin (A:G) ratio maintained?
- A. Nephritic syndrome (Correct Answer)
- B. Cirrhosis
- C. Protein losing enteropathy
- D. Multiple myeloma
Explanation: ***Nephritic syndrome*** - In nephritic syndrome, the **glomerular filtration is often preserved**, allowing for the maintenance of A:G ratio despite the presence of hematuria and proteinuria [1]. - The condition typically leads to a **moderate degree of proteinuria**, retaining a relatively normal serum albumin level [1]. *Multiple myeloma* - In multiple myeloma, there is often a **high level of paraproteins** leading to a significant drop in albumin, affecting the A:G ratio. - Patients frequently exhibit **renal impairment**, resulting in a disrupted A:G ratio due to increased urinary protein loss. *Protein losing enteropathy* - This condition causes **loss of proteins** like albumin through the gastrointestinal tract, leading to **hypoalbuminemia** and altered A:G ratio. - It is characterized by **diarrhea** and fluid accumulation, further impacting the protein status in circulation. *Cirrhosis* - Cirrhosis leads to **decreased albumin synthesis**, resulting in a low serum albumin and an altered A:G ratio. - The condition is associated with **portal hypertension** and ascites, complicating the biochemical status.
Question 795: A 68-year-old patient presents with sudden onset of right-sided weakness and slurred speech. The symptoms completely resolve within 30 minutes with no residual neurological deficits. This clinical presentation is most consistent with:
- A. Transient Ischemic Attack (TIA) (Correct Answer)
- B. Subarachnoid hemorrhage
- C. Intracerebral hemorrhage
- D. Ischemic stroke
Explanation: ***Transient Ischemic Attack (TIA)*** - A TIA is characterized by **transient neurological dysfunction caused by focal brain, spinal cord, or retinal ischemia**, without acute infarction [1]. - The key diagnostic feature here is the **complete resolution of symptoms within a short period** (30 minutes) with no residual deficits, fitting the definition of TIA [1]. *Subarachnoid hemorrhage* - This typically presents with a **sudden, severe headache** (often described as "thunderclap"), stiff neck, and altered mental status. - While it can cause sudden neurological deficits, these symptoms usually **do not resolve completely within minutes**, and often lead to persistent deficits or life-threatening complications. *Intracerebral hemorrhage* - An intracerebral hemorrhage involves **bleeding directly into the brain tissue**, leading to sudden onset of neurological deficits that **progress over time** [2]. - The symptoms are generally **severe and persistent**, and would not resolve completely within 30 minutes. *Ischemic stroke* - An ischemic stroke is caused by a **blockage of blood flow to the brain**, resulting in brain tissue damage (infarction) and persistent neurological deficits [2]. - While initial symptoms can be similar to a TIA [3], an ischemic stroke by definition involves **permanent damage and lasting deficits**, unlike what is described in the patient's presentation.
Question 796: Pea soup diarrhea is seen in -
- A. Cholera
- B. Typhoid (Correct Answer)
- C. Yersinosis
- D. Hepatitis
Explanation: ***Typhoid*** - **Pea soup diarrhea** is a classic symptom of **typhoid fever**, caused by *Salmonella Typhi* [1]. - This characteristic stool is a greenish-yellow watery diarrhea due to inflammation and ulceration of the Peyer's patches in the small intestine [1]. *Cholera* - Characterized by **rice-water stools**, which are profuse, watery, and often contain flecks of mucus, resembling water in which rice has been rinsed [2]. - This type of diarrhea is due to the potent **cholera toxin** causing massive fluid and electrolyte secretion [2]. *Yersinosis* - Causes diarrhea that can range from watery to bloody, often associated with severe **abdominal pain** mimicking appendicitis. - While it can cause enterocolitis, the stool consistency is not typically described as "pea soup" like in typhoid. *Hepatitis* - Hepatitis primarily affects the **liver** and typically does **not cause diarrhea** as a prominent symptom. - Common symptoms include jaundice, dark urine, and pale stools due to impaired bilirubin metabolism.
Question 797: Which of the following is not a treatment option for hypercalcemia?
- A. Strontium (Correct Answer)
- B. Bisphosphonates
- C. Steroids
- D. Phosphate
Explanation: ***Strontium*** - **Strontium ranelate** is primarily used in the treatment of **osteoporosis** to promote bone formation and inhibit bone resorption. - It does not have a recognized role in the acute or long-term management of **hypercalcemia** and could potentially worsen it due to its bone-targeting effects if not carefully managed. *Steroids* - **Glucocorticoids** are effective in treating hypercalcemia associated with **granulomatous diseases** (e.g., sarcoidosis) and certain malignancies (e.g., multiple myeloma) by reducing calcitriol production or tumor burden. - They decrease intestinal calcium absorption and increase renal calcium excretion in conditions where 1,25-dihydroxyvitamin D is elevated. *Bisphosphonates* - **Bisphosphonates** (e.g., zoledronic acid, pamidronate) are potent inhibitors of **osteoclast-mediated bone resorption** and are a cornerstone in the treatment of moderate to severe hypercalcemia, especially due to malignancy. [1] - They are administered intravenously and act by inducing osteoclast apoptosis, thereby reducing the release of calcium from bone. [1] *Phosphate* - **Intravenous phosphate** can be used in severe, resistant hypercalcemia, as it promotes calcium deposition into bone and soft tissues, and forms insoluble calcium-phosphate complexes, thus lowering serum calcium. - Its use is limited due to risks of **ectopic calcification**, renal failure, and hypotension, and it is usually reserved for life-threatening situations where other treatments have failed.
Question 798: Which of the following is commonly seen in Polycythemia Vera?
- A. Hyperuricemia
- B. Prone for acute leukemia
- C. Spontaneous severe infection
- D. Thrombosis (Correct Answer)
Explanation: ***Spontaneous severe infection*** - In Polycythemia Vera, there is usually an **increased red blood cell mass** leading to complications like thrombosis, rather than a predisposition to severe infections. - Severe infections are not a typical feature, as the condition usually maintains **functional immunity** despite hyperviscosity. *Thrombosis* - Individuals with Polycythemia Vera have increased blood viscosity that results in a higher risk of **thrombosis**, which is a common complication [1]. - Events like **deep vein thrombosis (DVT)** or **cerebral venous sinus thrombosis** are often observed due to altered hemodynamics. *Hyperuricemia* - Hyperuricemia occurs due to increased cell turnover and breakdown of red cells in Polycythemia Vera, leading to elevated **uric acid levels** [1]. - Patients may experience **gout attacks** as a consequence of this elevated uric acid [1]. *Prone for acute leukemia* - While there is an increased risk of transformation to myeloid neoplasms, the risk for **acute leukemia** is not directly attributed to Polycythemia Vera in most cases. - It is more related to myelofibrosis or secondary conditions developing over time rather than a direct association.
Physiology
1 questionsWhat is the expected Transtubular Potassium Gradient (TTKG) in a patient with hypokalemia due to extrarenal losses?
NEET-PG 2013 - Physiology NEET-PG Practice Questions and MCQs
Question 791: What is the expected Transtubular Potassium Gradient (TTKG) in a patient with hypokalemia due to extrarenal losses?
- A. < 3-4 (Correct Answer)
- B. 3-4
- C. > 4-5
- D. > 5-6
Explanation: ***< 3-4*** - A **Transtubular Potassium Gradient (TTKG)** of less than 3-4 indicates appropriate renal potassium conservation in response to hypokalemia. - This suggests that the hypokalemia is likely due to **extrarenal losses**, such as gastrointestinal losses (diarrhea, vomiting) or inadequate dietary intake, as the kidneys are working to retain potassium. *3-4* - A TTKG value in this range is typically considered indeterminate but could still point towards appropriate renal conservation if other clinical signs of extrarenal losses are present. - However, it does not as strongly confirm appropriate renal conservation as a value clearly below 3. *> 4-5* - A TTKG greater than 4-5 suggests **inappropriate renal potassium excretion** for a patient with hypokalemia. - This would indicate that the kidneys are complicit in the potassium loss, pointing towards renal causes of hypokalemia, such as **mineralocorticoid excess** or **diuretic use**. *> 5-6* - A TTKG greater than 5-6 strongly indicates significant **renal potassium wasting**. - This would be seen in conditions where the kidneys are actively secreting potassium despite hypokalemia, thereby contributing to the low potassium levels rather than conserving it.