Nephrology Practice Questions

Q: What is the best prophylactic drug for a 60-year-old asthmatic female with microalbuminuria of 280mg?

Telmisartan. **Explanation:** The clinical presentation describes a patient with **Moderately Increased Albuminuria** (formerly microalbuminuria, defined as 30–300 mg/day) [1],[3]. In patients with albuminuria, the primary goal is to provide renoprotection by blocking the Renin-Angiotensin-Aldosterone System (RAAS) [1]. **Why Telmisartan is the Correct Answer:** Both ACE inhibitors (ACEIs) and Angiotensin II Receptor Blockers (ARBs) are first-line agents for renoprotection as they dilate the efferent arteriole, reducing intragulomerular pressure and protein excretion [1]. However, this patient is **asthmatic**. ACE inhibitors like **Enalapril** are associated with a dry cough (due to increased bradykinin and substance P) which can exacerbate respiratory symptoms or be confused with asthma symptoms [2]. **Telmisartan (an ARB)** provides the same renoprotective benefits without affecting bradykinin levels, making it the safer and preferred choice in an asthmatic patient [2]. **Analysis of Incorrect Options:** * **A & B (Amiloride & Spironolactone):** These are potassium-sparing diuretics. While Spironolactone has some role in resistant proteinuria, they are not first-line prophylactic agents for microalbuminuria and carry a high risk of hyperkalemia. * **C (Enalapril):** While effective for proteinuria, the risk of inducing a "bradykinin-mediated cough" [2] makes it less ideal than an ARB for a patient with a pre-existing reactive airway disease (asthma). **Clinical Pearls for NEET-PG:** * **Drug of Choice (DOC)** for diabetic/hypertensive nephropathy: ACEIs or ARBs [1]. * **Mechanism:** Efferent arteriolar vasodilation → ↓ Glomerular capillary pressure [1],[2]. * **Contraindication:** Never combine ACEIs and ARBs (risk of hyperkalemia and acute kidney injury). * **Monitoring:** Always monitor serum creatinine and potassium levels within 1–2 weeks of starting RAAS blockers [2]. A rise in creatinine up to 30% is considered acceptable [1].

Q: Which of the following is NOT true about polycystic kidney disease?

Decompression of cysts leads to normal renal function. **Explanation:** Autosomal Dominant Polycystic Kidney Disease (ADPKD) is the most common inherited renal disorder [1]. Understanding its pathophysiology is crucial for the NEET-PG. **Why Option D is the correct answer (False statement):** Decompression of cysts (surgical or radiological) is performed primarily for symptomatic relief, such as intractable pain or pressure symptoms [1]. It **does not** restore or normalize renal function. The decline in GFR in ADPKD is due to the progressive replacement of normal renal parenchyma by cysts and subsequent interstitial fibrosis, which is irreversible [1]. **Analysis of other options:** * **Option A:** ADPKD follows an **autosomal dominant** inheritance pattern, primarily involving mutations in the *PKD1* (85%, Chromosome 16) and *PKD2* (15%, Chromosome 4) genes [1]. * **Option B:** Proteinuria in ADPKD is typically mild, usually **less than 2 g/day**. Nephrotic-range proteinuria is rare and suggests a secondary pathology (like FSGS). * **Option C:** ADPKD is a progressive condition. Approximately 50% of patients develop **End-Stage Renal Disease (ESRD)** or CRF by age 60, requiring dialysis or transplantation [1]. **Clinical Pearls for NEET-PG:** * **Extra-renal manifestations:** Hepatic cysts (most common), Berry aneurysms (Circle of Willis), Mitral Valve Prolapse (MVP), and diverticulosis. * **Diagnosis:** Ultrasonography is the first-line investigation (Ravine’s criteria). * **Management:** Tolvaptan (V2 receptor antagonist) is used to slow cyst growth and disease progression. * **Key Association:** Hypertension is often the earliest clinical sign, appearing even before a decline in GFR.

Q: Which of the following is true about nephrogenic diabetes insipidus?

Renal tubule is unresponsive to ADH. **Explanation:** **Nephrogenic Diabetes Insipidus (NDI)** is a clinical syndrome characterized by the inability of the kidneys to concentrate urine despite the presence of adequate levels of Antidiuretic Hormone (ADH/Vasopressin) [1]. 1. **Why Option A is Correct:** The fundamental defect in NDI is the **resistance of the renal collecting ducts to ADH**. This is usually due to mutations in the V2 receptor (X-linked recessive) or the Aquaporin-2 water channels, or acquired causes like Lithium toxicity and hypercalcemia [1], [2]. Since the tubules cannot respond to ADH, water reabsorption fails, leading to polyuria. 2. **Why Other Options are Incorrect:** * **Option B:** A central decrease in ADH secretion defines **Central Diabetes Insipidus**, not nephrogenic. In NDI, ADH levels are actually normal or elevated. * **Option C:** Patients lose free water in the urine, leading to hemoconcentration. Therefore, **Hypernatremia** (high serum sodium) is the classic finding, especially if the patient's thirst mechanism is impaired or access to water is restricted. * **Option D:** In the **Water Deprivation Test**, NDI is distinguished by a **failure to increase urine osmolality** after exogenous ADH (Desmopressin) administration [2], because the "end-organ" (kidney) is unresponsive. **High-Yield Clinical Pearls for NEET-PG:** * **Most common inherited cause:** X-linked recessive mutation in the **V2 receptor**. * **Most common drug-induced cause:** **Lithium** (it enters via ENaC channels and inhibits signaling). * **Electrolyte triggers:** **Hypercalcemia** and **Hypokalemia** can both induce NDI [2]. * **Treatment:** Thiazide diuretics (paradoxical effect), NSAIDs (Indomethacin), and a low-salt diet. Amiloride is specifically used for Lithium-induced NDI.

Q: Dysmorphic RBCs with acute renal failure (ARF) are most commonly seen in which condition?

Glomerular disease. The presence of **dysmorphic Red Blood Cells (RBCs)** in urine is a hallmark of **Glomerular disease** [1]. When RBCs pass through the damaged glomerular basement membrane (GBM) and travel through the varying osmotic gradients of the renal tubules, they undergo mechanical trauma and osmotic stress. This results in morphological changes such as blebbing, fragmentation, and the formation of **acanthocytes** (G1 cells), which are highly specific for glomerular bleeding. In the context of Acute Renal Failure (ARF), this finding strongly suggests **Acute Glomerulonephritis (AGN)** or Rapidly Progressive Glomerulonephritis (RPGN) [1]. **Analysis of Incorrect Options:** * **Renal Carcinoma:** This typically causes **isomorphic (normal-shaped) RBCs** because the bleeding occurs from the vascular supply of the tumor into the collecting system, bypassing the mechanical stress of the glomerular filter [1]. * **Proximal and Distal Tubule Disease:** While tubular diseases (like Acute Tubular Necrosis) are common causes of ARF, they typically present with **casts** (e.g., muddy brown casts) and tubular epithelial cells rather than dysmorphic RBCs. Hematuria is not a primary feature of isolated tubular injury. **NEET-PG High-Yield Pearls:** * **Acanthocytes:** The most specific type of dysmorphic RBC; if >5% of total urinary RBCs are acanthocytes, glomerular disease is highly likely. * **RBC Casts:** These are pathognomonic for glomerular hemorrhage. * **Isomorphic RBCs:** Suggest "urological" bleeding (stones, malignancy, or infections). * **Phase-contrast microscopy:** The gold standard method for identifying RBC morphology in urine.

Q: Microalbuminuria is defined as a urinary protein level in which range?

30-300 mg/day. **Explanation:** Microalbuminuria refers to a level of albumin excretion that is higher than normal but below the detection limit of a standard urine dipstick [1]. It is a critical clinical marker for early-stage diabetic nephropathy and cardiovascular risk [1]. 1. **Why Option B is Correct:** The standard clinical definition of microalbuminuria is a urinary albumin excretion rate of **30–300 mg/day** (or 20–200 µg/min). In a spot urine sample, this corresponds to an **Albumin-to-Creatinine Ratio (ACR) of 30–300 mg/g**. Values below 30 mg/day are considered normal, while values above 300 mg/day are classified as "macroalbuminuria" or overt proteinuria [2]. 2. **Why Other Options are Incorrect:** * **Option A (30-200 mg/day):** This is a common distractor; while 200 µg/min is the upper limit in timed collections, the daily excretion limit is 300 mg. * **Options C & D:** These ranges are arbitrarily lower and do not align with the established KDIGO or ADA guidelines for defining incipient nephropathy. **Clinical Pearls for NEET-PG:** * **Screening:** The most sensitive and preferred screening method is the **Spot Morning Urine Albumin-to-Creatinine Ratio (ACR)**. [1] * **Diagnosis:** Diagnosis requires at least **two out of three** positive specimens collected over a 3- to 6-month period, as transient elevations can occur due to exercise, fever, or heart failure. * **Significance:** It is the earliest sign of diabetic nephropathy and is reversible with strict glycemic control and **ACE inhibitors or ARBs**, which provide Reno-protection. [2]

Q: HIV-induced nephropathy is more common in which of the following subsets of HIV patients?

Intravenous drug abusers. **Explanation:** **HIV-Associated Nephropathy (HIVAN)** is a classic form of renal involvement in HIV patients, characterized histologically by **Collapsing Focal Segmental Glomerulosclerosis (FSGS)** [1]. **Why Intravenous Drug Abusers (IVDAs) are the correct answer:** Epidemiological studies have consistently shown that HIVAN has a strong predilection for specific demographics. It is most common in **African Americans** (due to the APOL1 genetic risk variant) and **Intravenous Drug Abusers** [2]. The association with IVDAs is likely multifactorial, involving both the direct cytopathic effects of HIV on the glomerular epithelium and the potential synergistic renal damage caused by injected substances (like heroin, which independently causes "Heroin Nephropathy"). **Analysis of Incorrect Options:** * **A & B (Homosexuals and Heterosexuals):** While HIV is frequently transmitted via sexual routes, these subsets do not show a disproportionately higher incidence of HIVAN compared to the IVDA population, unless they also belong to the high-risk African American genotype. * **D (Congenital HIV):** While children with congenital HIV can develop renal disease, the classic "HIVAN" phenotype is significantly more prevalent in the adult IVDA population. **NEET-PG High-Yield Pearls:** * **Histology:** Collapsing FSGS is the hallmark (look for "wrinkling and collapse of the glomerular basement membrane") [1]. * **Clinical Presentation:** Rapidly progressive renal failure, heavy proteinuria (nephrotic range), and **normal-sized or enlarged kidneys** on ultrasound (unlike most chronic kidney diseases where kidneys shrink). * **Treatment:** Highly Active Antiretroviral Therapy (HAART) is the mainstay of treatment and can slow progression. * **Genetic Link:** Strongly associated with **APOL1 gene** polymorphisms on chromosome 22.

Question 1

What is the best prophylactic drug for a 60-year-old asthmatic female with microalbuminuria of 280mg?

Accepted Answer

Telmisartan

Answer

Amiloride

Answer

Spironolactone

Answer

Enalapril

Question 2

Which of the following is NOT true about polycystic kidney disease?

Accepted Answer

Decompression of cysts leads to normal renal function

Answer

Autosomal dominant inheritance

Answer

Proteinuria is typically less than 2 gm/day

Answer

It can lead to chronic renal failure (CRF)

Question 3

Hypokalemia is seen in all the following conditions except?

Accepted Answer

21 hydroxylase deficiency

Answer

Bartter syndrome

Answer

Hypokalemic periodic paralysis

Answer

Reninoma (juxtaglomerular cell tumor)

Question 4

Renal Tubular Acidosis (RTA) shows all except?

Accepted Answer

Vitamin D deficiency

Answer

Urine pH always >5.5

Answer

Anion gap normal

Answer

Bicarbonaturia

Question 5

Which of the following is true about nephrogenic diabetes insipidus?

Accepted Answer

Renal tubule is unresponsive to ADH

Answer

There is central decrease in secretion of ADH

Answer

Serum sodium is low

Answer

Urine osmolality is increased after administration of ADH

Question 6

Which investigation is most crucial for the diagnosis of idiopathic membranous glomerulopathy?

Accepted Answer

Antibody to PLA2R on podocytes

Answer

Kidney biopsy with immunofluorescent staining

Answer

C3, C4, and CH50 levels

Answer

c-ANCA titers

Question 7

A 50-year-old diabetic patient presents with general malaise. On workup, his serum creatinine is 5.0 mg/dL and blood urea is 125 mg/dL. The urine MICRAL test is positive. Which of the following medications would be beneficial for this patient?

Accepted Answer

Diuretics

Answer

Cardio-selective beta-blocker

Answer

ACE inhibitor

Answer

Amiodarone

Question 8

Dysmorphic RBCs with acute renal failure (ARF) are most commonly seen in which condition?

Accepted Answer

Glomerular disease

Answer

Renal carcinoma

Answer

Proximal tubule disease

Answer

Distal tubule disease

Question 9

Microalbuminuria is defined as a urinary protein level in which range?

Accepted Answer

30-300 mg/day

Answer

30-200 mg/day

Answer

30-150 mg/day

Answer

30-100 mg/day

Question 10

HIV-induced nephropathy is more common in which of the following subsets of HIV patients?

Accepted Answer

Intravenous drug abusers

Answer

Homosexuals

Answer

Heterosexuals

Answer

Congenital HIV

Nephrology — MCQs

Nephrology — MCQs

On this page

Practice by Chapter

Want unlimited practice?