**Question:** Commonest presentation of bilateral ureteric stones -

A. Painful flank
B. Asymptomatic
C. Ureteric colic
D. Acute pyelonephritis

**Core Concept:** Ureteric stones are solid particles that form within the ureter, typically due to the presence of salts, proteins, or other substances in the urine. When these stones obstruct the flow of urine, they can cause symptoms and complications.

**Why the Correct Answer is Right:**

The correct answer is **D. Acute pyelonephritis**. Acute pyelonephritis is a bacterial infection that affects the kidneys. When the ureter is obstructed by bilateral ureteric stones, the bacteria can ascend from the lower urinary tract to the kidneys, leading to an increased risk of pyelonephritis. Ureteric stones can cause hydronephrosis (watery swelling) and inflammation in the renal parenchyma, which is the renal cortex and medulla.

**Why Each Wrong Option is Incorrect:**

A. Painful flank (Option A) is a symptom, not a presentation. Painful flank refers to the characteristic flank pain experienced by patients with ureteric stones.

B. Asymptomatic (Option B) means showing no symptoms, which contradicts the question's premise that bilateral ureteric stones are causing symptoms.

C. Ureteric colic (Option C) is a term used to describe the acute attack of pain caused by ureteric stones. It does not describe the commonest presentation of bilateral ureteric stones.

**Clinical Pearl:**

Understanding the relationship between ureteric stones and complications like pyelonephritis is crucial for accurate diagnosis and timely treatment of patients presenting with symptoms related to ureteric stones. A thorough clinical examination, including assessing for fever, costovertebral angle tenderness, and renal angle tenderness, is essential in assessing patients for complications like pyelonephritis. A prompt diagnosis and treatment can prevent the progression of these complications and minimize long-term renal damage.

In summary, the correct answer (D) highlights the potential complications of ureteric stones, particularly when they obstruct the urinary tract bilaterally. Understanding the pathophysiology of these complications is crucial for accurate diagnosis and management of patients presenting with symptoms related to ureteric stones.