Biochemistry
1 questionsCystatin C levels are used for
NEET-PG 2013 - Biochemistry NEET-PG Practice Questions and MCQs
Question 1121: Cystatin C levels are used for
- A. Detecting UTI
- B. Estimating GFR (Correct Answer)
- C. Screening for Renal Ca
- D. Estimating difference between CRF and ARF
Explanation: ***Estimating GFR*** - **Cystatin C** is a **proteinase inhibitor** produced by all nucleated cells at a constant rate, and its level in the blood is inversely related to the **glomerular filtration rate (GFR)**. - Unlike **creatinine**, Cystatin C levels are less affected by **muscle mass, diet, or inflammation**, making it a more reliable marker for early and subtle changes in GFR, especially in certain populations. *Detecting UTI* - **Urinary tract infections (UTIs)** are primarily detected through **urinalysis** (presence of **leukocytes, nitrites**, and **bacteria**) and **urine culture**. - **Cystatin C** is a serum marker for renal function and has no direct role in detecting the presence of bacterial infection in the urinary tract. *Estimating difference between CRF and ARF* - Differentiating between **chronic renal failure (CRF)** and **acute renal failure (ARF)** typically involves assessing the **chronicity of symptoms**, trend in **creatinine levels**, and **kidney size** and **echogenicity** on ultrasound. - While Cystatin C can reflect current GFR, it doesn't inherently provide discriminatory power between acute and chronic processes without serial measurements or additional clinical context. *Screening for Renal Ca* - **Renal cell carcinoma (RCC)** screening is primarily done using **imaging techniques** like **ultrasonography, CT, or MRI**, especially in individuals with risk factors or symptoms like **hematuria**. - **Cystatin C** is a marker of kidney function and does not serve as a tumor marker for renal cancer.
Internal Medicine
8 questionsThe physiological marker of the last stage of acute asthma is
Which of the following is a characteristic finding in distal RTA?
Which of the following is not a feature of distal renal tubular acidosis
Hyperkalemia aciduria is seen in
A diabetic patient presents with hyperkalemia and urinary pH < 5.5. What is the MOST likely underlying cause?
Calciphylaxis is a severe life-threatening condition. Which of the following is most commonly associated with it?
What is the primary clinical feature of Henoch-Schonlein purpura?
Interstitial nephritis is common with
NEET-PG 2013 - Internal Medicine NEET-PG Practice Questions and MCQs
Question 1121: The physiological marker of the last stage of acute asthma is
- A. Hypocapnia
- B. Hyperoxia
- C. Alkalosis
- D. Increased carbon dioxide levels (Hypercapnia) (Correct Answer)
Explanation: ***Increased carbon dioxide levels (Hypercapnia)*** - In severe, acute asthma, **air trapping** and **muscle fatigue** lead to inadequate ventilation and impaired gas exchange [1]. - This results in a buildup of carbon dioxide in the blood, indicating impending **respiratory failure** and a critical stage of the asthma exacerbation [3]. *Hypocapnia* - **Hypocapnia**, or low blood CO2, is common in the **early stages** of an asthma attack due to **tachypnea** (rapid breathing) in an effort to compensate [1]. - As the condition worsens, the ability to ventilate adequately diminishes, leading to CO2 retention [3]. *Hyperoxia* - **Hyperoxia** means abnormally high levels of oxygen in the blood, which is generally not a physiological marker of acute asthma. - Patients with acute asthma typically experience **hypoxemia** (low oxygen levels) due to ventilation-perfusion mismatch [1]. *Alkalosis* - **Respiratory alkalosis** (high pH due to low CO2) can occur in the early stages as patients **hyperventilate**. - However, in the late stages, as CO2 builds up (**hypercapnia**), the patient shifts towards **respiratory acidosis** (low pH), which is a sign of severe compromise [2], [3].
Question 1122: Which of the following is a characteristic finding in distal RTA?
- A. Urine pH < 5.5
- B. Hypokalemia
- C. Hypercalciuria (Correct Answer)
- D. Nephrolithiasis
Explanation: ***Hypercalciuria*** - **Hypercalciuria** is a characteristic finding in distal RTA (Type 1), leading to increased calcium in the urine. - This occurs due to reduced **distal tubular reabsorption of calcium** and increased bone resorption from chronic acidosis. *Urine pH < 5.5* - In distal RTA, the kidneys are unable to acidify the urine properly, leading to a **urine pH > 5.5** [1]. - A urine pH < 5.5 would suggest a normal kidney response to systemic acidosis, ruling out distal RTA. *Hypokalemia* - While hypokalemia can occur in distal RTA, it is not always present and is not the most definitive characteristic finding. - **Hypokalemia** is more characteristic of Type 1 RTA due to increased potassium excretion in an attempt to excrete H+ ions. *Nephrolithiasis* - **Nephrolithiasis** (kidney stones) is a common complication of distal RTA due to hypercalciuria and alkaline urine [2]. - However, hypercalciuria is the *reason* for the increased risk of nephrolithiasis, making it a more fundamental characteristic finding.
Question 1123: Which of the following is not a feature of distal renal tubular acidosis
- A. Renal hypercalciuria
- B. Normal anion gap
- C. Hyperkalemia (Correct Answer)
- D. Alkaline urine
Explanation: ***Hyperkalemia*** - **Distal renal tubular acidosis (dRTA)** is characterized by impaired acid excretion, leading to metabolic acidosis. The impaired excretion of acid is often accompanied by impaired potassium secretion, resulting in **hypokalemia**, not hyperkalemia. - While hyperkalemia is a feature of **type 4 RTA**, which is characterized by hypoaldosteronism or renal tubular unresponsiveness to aldosterone, it is not a feature of **distal RTA (type 1)**. [1] *Normal anion gap* - **Distal RTA** is a form of **normal anion gap metabolic acidosis**, also known as **hyperchloremic metabolic acidosis**. [1] - The anion gap is calculated as [Na+] - ([Cl-] + [HCO3-]), and in dRTA, the bicarbonate loss is compensated by an increase in chloride, maintaining a normal anion gap. *Renal hypercalciuria* - **Distal RTA** is associated with **impaired acid excretion**, which leads to chronic metabolic acidosis. - This **acidosis** promotes the dissolution of bone, releasing calcium, and decreases tubular reabsorption of calcium, resulting in **hypercalciuria**. *Alkaline urine* - In **distal RTA**, the distal tubule is unable to acidify the urine due to a defect in hydrogen ion secretion. - This leads to a persistent **urine pH > 5.5** (typically alkaline or inappropriately normal) despite systemic acidosis, making it a key diagnostic feature. [1]
Question 1124: Hyperkalemia aciduria is seen in
- A. Type I Renal Tubular Acidosis
- B. Type IV Renal Tubular Acidosis (Correct Answer)
- C. Sigmoidocolostomy procedure
- D. Type II Renal Tubular Acidosis
Explanation: Type IV Renal Tubular Acidosis - This condition is characterized by **hyperkalemia** and **aciduria**, often due to a deficiency in aldosterone or a renal tubular insensitivity to aldosterone [1]. - The impaired aldosterone action leads to reduced potassium excretion and decreased ammonium production, both contributing to **hyperkalemia** and metabolic acidosis [1]. *Type I Renal Tubular Acidosis* - Type I RTA (distal RTA) is characterized by a defect in acid secretion in the distal tubule, leading to **hypokalemia** and metabolic acidosis with persistently high urine pH [2]. - Patients typically excrete an alkaline urine despite systemic acidosis, contrasting with the aciduria seen with hyperkalemia [2]. *Sigmoidocolostomy procedure* - A sigmoidocolostomy can lead to **hyperchloremic metabolic acidosis** due to the reabsorption of chloride and excretion of bicarbonate by the colonic mucosa. - However, it typically causes **hypokalemia** as potassium is secreted into the colonic lumen from the blood. *Type II Renal Tubular Acidosis* - Type II RTA (proximal RTA) involves a defect in bicarbonate reabsorption in the proximal tubule, resulting in **hypokalemia** and metabolic acidosis. - The kidney's ability to acidify urine is still largely intact in the distal nephron once the bicarbonate buffer system is overwhelmed.
Question 1125: A diabetic patient presents with hyperkalemia and urinary pH < 5.5. What is the MOST likely underlying cause?
- A. Uremia
- B. Primary hyperaldosteronism
- C. Type IV RTA (Correct Answer)
- D. Type I Renal tubular acidosis
Explanation: ***Type IV RTA*** - Patients with **diabetes mellitus** frequently develop **hyporeninemic hypoaldosteronism**, leading to Type IV RTA [1]. - This condition is characterized by **hyperkalemia** and **acidosis** with a paradoxically low urinary pH (typically < 5.5). *Uremia* - **Uremia** can cause hyperkalemia and acidosis, but it is a broader term for severe kidney failure and not the most specific underlying cause for the given urinary findings. - While patients with uremia can have aciduria, the combination of **diabetic hyperkalemia** and acid urine points more directly to a specific tubular defect. *Primary hyperaldosteronism* - **Primary hyperaldosteronism** is characterized by **hypertension**, **hypokalemia**, and metabolic alkalosis, which is the opposite of the patient's presentation [1]. - This condition involves excessive aldosterone production, leading to increased potassium excretion [1]. *Type I Renal tubular acidosis* - **Type I RTA** (distal RTA) is characterized by the inability to acidify urine, resulting in a **urinary pH > 5.5** despite systemic acidosis [1]. - While it can cause hypokalemia (due to increased distal K+ secretion) and acidosis, the elevated urinary pH is a key differentiating factor from this patient's presentation [1].
Question 1126: Calciphylaxis is a severe life-threatening condition. Which of the following is most commonly associated with it?
- A. Parathyroidectomy
- B. Medullary carcinoma thyroid
- C. Hyperthyroidism
- D. End stage Renal disease (Correct Answer)
Explanation: ***End stage Renal disease*** - Calciphylaxis frequently occurs in patients with **end-stage renal disease**, primarily associated with **secondary hyperparathyroidism** [1] and **calcium-phosphate imbalance**. - It leads to **cutaneous ischemia** and necrosis, often requiring aggressive management due to its high **mortality rate**. *Parathyroidectomy* - While parathyroidectomy may affect calcium levels, it is not directly linked to calciphylaxis. - Calciphylaxis more commonly develops due to underlying **chronic renal failure** [1] rather than surgical interventions. *Hyperthyroidism* - Hyperthyroidism primarily causes symptoms related to metabolism, **thyroid hormone excess**, and does not lead to calciphylaxis. - There is no direct correlation between hyperthyroid states and the pathophysiology of calciphylaxis. *Medullary carcinoma thyroid* - This condition involves **medullary thyroid carcinoma**, associated with calcitonin production and does not cause calciphylaxis. - Patients typically experience **thyroid-related symptoms** rather than the vascular complications seen in calciphylaxis.
Question 1127: What is the primary clinical feature of Henoch-Schonlein purpura?
- A. Abdominal pain due to vasculitis
- B. Joint pain associated with the condition
- C. Kidney involvement in the disease
- D. Skin rash characterized by palpable purpura (Correct Answer)
Explanation: ***Skin rash characterized by palpable purpura*** - **Palpable purpura** is the hallmark cutaneous manifestation of **Henoch-Schonlein purpura (HSP)**, a small-vessel vasculitis [1]. - This rash typically appears on the **lower extremities and buttocks**, reflecting the deposition of IgA in vessel walls [1]. *Abdominal pain due to vasculitis* - While **abdominal pain** is a common feature of HSP due to gastrointestinal vasculitis, it is not considered the primary clinical feature [1]. - Gastrointestinal involvement can manifest with pain, bleeding, and intussusception, but the **skin rash** is more consistently present and diagnostic. *Joint pain associated with the condition* - **Arthralgia** or **arthritis** (joint pain) is seen in a significant number of HSP patients, particularly in the knees and ankles. - However, it is a secondary manifestation, and not the **defining primary sign** of the disease. *Kidney involvement in the disease* - **Renal involvement**, presenting as hematuria and proteinuria, occurs in about one-third of HSP cases and can lead to serious long-term complications. - Despite its significance for prognosis, **kidney disease** is a later and not universally present feature, making the rash the most critical initial diagnostic clue.
Question 1128: Interstitial nephritis is common with
- A. Black water fever
- B. Rhabdomyolysis
- C. Tumor lysis syndrome
- D. Nonsteroidal anti-inflammatory drugs (NSAIDs) (Correct Answer)
Explanation: ***Nonsteroidal anti-inflammatory drugs (NSAIDs)*** - **NSAIDs** are a known cause of **acute interstitial nephritis** (AIN), an inflammatory condition affecting the tubules and interstitium of the kidney [1]. - This adverse reaction often manifests as **fever**, **rash**, **eosinophilia**, and **acute kidney injury**, typically 7-10 days after drug exposure. *Black water fever* - **Blackwater fever** is a severe complication of **malaria**, characterized by massive hemolysis leading to **hemoglobinuria**, which darkens the urine. - It primarily causes **acute kidney injury** through **acute tubular necrosis** due to hemoglobin precipitation in the renal tubules, not interstitial nephritis. *Rhabdomyolysis* - **Rhabdomyolysis** involves the breakdown of muscle tissue, releasing myoglobin into the bloodstream, which is toxic to the kidneys. [1] - This condition leads to **acute kidney injury** predominantly through **acute tubular necrosis** due to myoglobin casts obstructing tubules and direct toxicity, not interstitial inflammation. *Tumor lysis syndrome* - **Tumor lysis syndrome** occurs when large numbers of cancer cells are rapidly destroyed, releasing intracellular contents like potassium, phosphate, and nucleic acids. - The high concentration of **uric acid** and **phosphate** in the renal tubules leads to crystal formation, causing **acute kidney injury** primarily through **acute uric acid nephropathy** and **phosphate nephropathy**, rather than interstitial nephritis [1].
Pharmacology
1 questionsWhat is the drug of choice for most forms of interstitial lung disease?
NEET-PG 2013 - Pharmacology NEET-PG Practice Questions and MCQs
Question 1121: What is the drug of choice for most forms of interstitial lung disease?
- A. Antibiotics
- B. Bronchodilators
- C. Aspirin
- D. Corticosteroids (Correct Answer)
Explanation: ***Corticosteroids*** - **Corticosteroids** are the **drug of choice** for many forms of **interstitial lung disease (ILD)** due to their potent **anti-inflammatory** and **immunosuppressive properties**, which help reduce lung inflammation and prevent fibrosis. - They are particularly effective in inflammatory ILDs such as **sarcoidosis**, **hypersensitivity pneumonitis**, and some **connective tissue disease-associated ILDs**. *Antibiotics* - **Antibiotics** are primarily used to treat bacterial and other microbial infections and are **not effective** against the **inflammatory and fibrotic processes** characteristic of most ILDs. - They might be used if there's a **secondary bacterial infection** complicating ILD, but not as primary treatment for the ILD itself. *Bronchodilators* - **Bronchodilators** work by relaxing the muscles around the airways, making them wider and easier to breathe through, which is beneficial in conditions like **asthma** or **COPD**. - They are **not primarily used** in ILD as the main problem is **inflammation and scarring of the lung tissue**, not reversible airway constriction. *Aspirin* - **Aspirin** is an **NSAID** with **anti-inflammatory**, **anti-platelet**, and **analgesic properties**, commonly used for pain relief, fever reduction, and cardiovascular protection. - It has **no established role** in the primary treatment of **interstitial lung disease**, as its anti-inflammatory effects are typically insufficient for the severe inflammation seen in ILD.