Question

Classify megaureter.

Hint:

Megaureter can be classified based on its cause (obstructive vs non-obstructive), pathophysiology (functional vs structural), and age of onset (congenital vs acquired).

Answer 1

Megaureter is a condition characterized by the dilation of the ureter, the tube that carries urine from the kidney to the bladder. The condition can be classified based on its cause (obstructive or non-obstructive), and its anatomical presentation.
Step 1: Classification Based on Cause:
1. Primary Megaureter: This type is present at birth and is often caused by a congenital abnormality, such as a malfunction in the development of the ureteral muscle or a defective valve in the ureterovesical junction (UVJ).
2. Secondary Megaureter: This type occurs as a result of an acquired obstruction or condition that affects the ureter, such as bladder outlet obstruction, stones, or tumors that block the normal flow of urine.
Step 2: Classification Based on Pathophysiology:
1. Obstructive Megaureter: This occurs when there is a blockage at any point in the ureter, such as at the UVJ or higher up in the ureter. This results in urine accumulation in the kidney, causing dilation of the ureter.
2. Non-Obstructive Megaureter: In this condition, there is no actual blockage, but the ureter is still dilated, usually due to a functional defect such as a defective peristalsis of the ureter.
Step 3: Classification Based on Age of Onset:
1. Congenital Megaureter: This is present from birth and is usually a result of a structural anomaly in the ureter or the UVJ. It is typically identified during infancy or early childhood.
2. Acquired Megaureter: This develops later in life due to conditions such as obstruction, infection, or other pathologies that lead to ureteral dilation.