In hydronephrosis from pelvi-ureteric junction (PUJ) obstruction (idiopathic or congenital hydronephrosis), which of the following statements are false?
## Core Concept
Hydronephrosis from pelvi-ureteric junction (PUJ) obstruction, also known as idiopathic or congenital hydronephrosis, occurs due to a blockage at the junction where the renal pelvis and the ureter meet. This obstruction prevents the normal flow of urine from the kidney to the ureter, leading to the accumulation of urine and subsequent dilation of the renal pelvis and calyces.
## Why the Correct Answer is Right
The correct answer choice isn't directly provided, but typically, in the context of PUJ obstruction:
- The obstruction is usually unilateral.
- It often presents with intermittent flank pain, especially after drinking large amounts of fluid.
- The condition can lead to complications such as infection (pyelonephritis) or kidney stones.
- Diagnostic imaging, such as ultrasound and intravenous pyelography (IVP), is crucial for confirming the diagnosis.
## Why Each Wrong Option is Incorrect
Without specific statements for A, B, C, and D, a general approach to evaluating false statements regarding hydronephrosis from PUJ obstruction:
- **Option A:** If a statement claims that PUJ obstruction is typically bilateral or always associated with a specific symptom (e.g., pain), and this is not generally accurate, then it would be incorrect.
- **Option B:** If a statement suggests that PUJ obstruction never leads to complications or that it always resolves spontaneously, this could be misleading as outcomes vary.
- **Option C:** A claim that PUJ obstruction is exclusively due to intrinsic causes (e.g., abnormal ureteral development) or extrinsic causes (e.g., compression by vessels) without acknowledging the variety of etiologies would be incomplete.
- **Option D:** If a statement inaccurately describes the diagnostic approach or the typical patient population (e.g., age, symptoms) affected by PUJ obstruction, it would be incorrect.
## Clinical Pearl / High-Yield Fact
A key point to remember is that PUJ obstruction can often be treated with surgical intervention, such as a pyeloplasty, which aims to remove the obstructed segment and reconnect the ureter to the renal pelvis, thereby restoring normal urine flow.
## Correct Answer Line
**Correct Answer: D.**