NEET-PG 2013 Practice Questions

Q: Which of the following is a characteristic finding in distal RTA?

Hypercalciuria. ***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** [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.

Q: Which of the following is not a feature of distal renal tubular acidosis

Hyperkalemia. ***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]

Q: Hyperkalemia aciduria is seen in

Type IV Renal Tubular Acidosis. 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.

Q: A diabetic patient presents with hyperkalemia and urinary pH < 5.5. What is the MOST likely underlying cause?

Type IV RTA. ***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].

Q: Calciphylaxis is a severe life-threatening condition. Which of the following is most commonly associated with it?

End stage Renal disease. ***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.

Q: What is the primary clinical feature of Henoch-Schonlein purpura?

Skin rash characterized by palpable purpura. ***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.

Q: Interstitial nephritis is common with

Nonsteroidal anti-inflammatory drugs (NSAIDs). ***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].

Q: "Bread-crumb" appearance is seen in ?

Complicated cataracts. ***Complicated cataracts*** - A "bread-crumb" appearance, specifically referring to small, refractile opacities in the posterior capsule, is a characteristic finding in **complicated cataracts**. - These cataracts often develop due to chronic intraocular diseases such as **uveitis**, **retinal detachment**, or **intraocular tumors**, leading to secondary lens changes. *Cataract due to diabetes* - Diabetic cataracts typically present as "snowflake" opacities in younger patients or accelerated nuclear/cortical sclerosis in older patients, not a "bread-crumb" appearance. - They are often associated with poor glycemic control and metabolic changes affecting lens hydration and protein structure. *Cataract due to CMV infection* - Cataracts associated with **cytomegalovirus (CMV) infection** are more common in congenital infections and can manifest as varying degrees of lens opacification, but "bread-crumb" is not a typical description. - Congenital CMV can cause a spectrum of ocular abnormalities, including microphthalmia, chorioretinitis, and optic atrophy, in addition to cataracts. *Cataract due to Toxoplasmosis* - **Toxoplasmosis** primarily causes **chorioretinitis**, especially in congenital cases, with lens involvement being less common and not typically described as having a "bread-crumb" appearance. - If a cataract develops, it's usually secondary to inflammation or direct lens invasion, but the characteristic morphology differs.

Q: In senile nuclear cataract what type of myopia is seen?

Index myopia. **Index myopia** - **Senile nuclear cataract** involves opacification and hardening of the lens nucleus, which increases the **refractive index** of the lens. - This results in a stronger refractive power of the eye, causing light to focus in front of the retina, characteristic of **myopia**. *Curvature myopia* - Occurs when there is an increase in the **curvature of the cornea** or lens, leading to increased refractive power. - While lens curvature can change, the primary mechanism in nuclear cataracts is refractive index change, not solely curvature. *Axial myopia* - Arises from an **elongation of the eyeball**, making the axial length too long relative to the refractive power. - This is a structural change in the eye's shape, not directly caused by changes within the lens itself due to cataract. *Lenticular myopia* - This term is a broader category that refers to myopia caused by changes in the lens, which **index myopia** falls under. - However, "index myopia" is more specific and accurately describes the underlying mechanism in senile nuclear cataracts.

Q: Polyopia/diplopia is seen in which type of cataract?

Cortical cataract. ***Cortical cataract*** - **Cortical cataracts** cause spokes or vacuoles that refract light in multiple directions, leading to **polyopia** or **diplopia**. - The irregular opacities disrupt the light path, causing the brain to perceive **multiple images**. *Nuclear cataract* - **Nuclear cataracts** primarily affect central vision and cause **myopic shift**, not typically polyopia or diplopia. - They cause **blurry vision** and difficulty seeing in dim light as the lens nucleus hardens and yellows. *Posterior subcapsular cataract* - **Posterior subcapsular cataracts** are characterized by glare and difficulty with reading, mainly affecting near vision. - They form at the back of the lens, close to the nodal point, causing earlier onset of **visual symptoms** with less impact on polyopia. *Anterior polar cataract* - **Anterior polar cataracts** are usually small, well-demarcated opacities at the front of the lens that typically do not cause significant visual impairment. - They rarely cause **polyopia** unless they are very large or dense, which is uncommon.

Question 1

Which of the following is a characteristic finding in distal RTA?

Accepted Answer

Hypercalciuria

Answer

Urine pH < 5.5

Answer

Hypokalemia

Answer

Nephrolithiasis

Question 2

Which of the following is not a feature of distal renal tubular acidosis

Accepted Answer

Hyperkalemia

Answer

Renal hypercalciuria

Answer

Normal anion gap

Answer

Alkaline urine

Question 3

Hyperkalemia aciduria is seen in

Accepted Answer

Type IV Renal Tubular Acidosis

Answer

Type I Renal Tubular Acidosis

Answer

Sigmoidocolostomy procedure

Answer

Type II Renal Tubular Acidosis

Question 4

A diabetic patient presents with hyperkalemia and urinary pH < 5.5. What is the MOST likely underlying cause?

Accepted Answer

Type IV RTA

Answer

Uremia

Answer

Primary hyperaldosteronism

Answer

Type I Renal tubular acidosis

Question 5

Calciphylaxis is a severe life-threatening condition. Which of the following is most commonly associated with it?

Accepted Answer

End stage Renal disease

Answer

Parathyroidectomy

Answer

Medullary carcinoma thyroid

Answer

Hyperthyroidism

Question 6

What is the primary clinical feature of Henoch-Schonlein purpura?

Accepted Answer

Skin rash characterized by palpable purpura

Answer

Abdominal pain due to vasculitis

Answer

Joint pain associated with the condition

Answer

Kidney involvement in the disease

Question 7

Interstitial nephritis is common with

Accepted Answer

Nonsteroidal anti-inflammatory drugs (NSAIDs)

Answer

Black water fever

Answer

Rhabdomyolysis

Answer

Tumor lysis syndrome

Question 8

"Bread-crumb" appearance is seen in ?

Accepted Answer

Complicated cataracts

Answer

Cataract due to CMV infection

Answer

Cataract due to diabetes

Answer

Cataract due to Toxoplasmosis

Question 9

In senile nuclear cataract what type of myopia is seen?

Accepted Answer

Index myopia

Answer

Curvature myopia

Answer

Axial myopia

Answer

Lenticular myopia

Question 10

Polyopia/diplopia is seen in which type of cataract?

Accepted Answer

Cortical cataract

Answer

Nuclear cataract

Answer

Posterior subcapsular cataract

Answer

Anterior polar cataract

NEET-PG 2013

Internal Medicine

Ophthalmology