NEPHROLOGY
Etiology
Obstruction: stones, BPH, tumors, pregnancy, strictures
Congenital causes in infants
Pathogenesis
Urinary obstruction → dilation of renal pelvis → back-pressure → atrophy of renal cortex
Prolonged obstruction → irreversible kidney damage
Clinical Features
Flank pain
Palpable kidney (in chronic cases)
Decreased urine output
Recurrent UTIs
Elevated creatinine (if bilateral)
Treatment
Relieve obstruction (stent, nephrostomy tube)
Remove stone, treat BPH, or surgery for structural causes