Many conditions can cause obstructive uropathy, which may be acute or chronic, partial or complete, and unilateral or bilateral.In children, the most common causes are anatomic abnormalities (including urethral valves or stricture and stenosis at the ureterovesical or ureteropelvic junction).In young adults, the most common cause is a calculus. In older adults, the most common causes are BPH or prostate cancer, retroperitoneal or pelvic tumors, and calculi. Obstruction may occur at any level, from the renal tubules to the external urethral meatus. Proximal to the obstruction, effects may include increased intraluminal pressure, urinary stasis, UTI, or calculus formation.Obstruction is much more common in males, but acquired and congenital urethral strictures and meatal stenosis occur in both males and females. In females, urethral obstruction may occur secondary to a tumor or as a result of stricture formation after radiation therapy, surgery, or urologic instrumentation.
Diagnosis is based on results of bladder catheterization, ultrasonography, CT, cystourethroscopy, cystourethrography, or pyelography, depending on the level of obstruction.