Introduction

• Cause: obstruction at level of renal pelvis (hydronephrosis) or ureter (hydroureter with possible hydronephrosis) → rapid deterioration of function of the affected kidney.
• Signs: acute or chronic renal failure.
• Diagnosis: imaging.
• Treatment: surgery, antibiotics.
• Prognosis: if treated early enough, renal function may still be intact → ureteral function may return to normal.

Pathogenesis

Etiology

• Urolithiasis Urolithiasis.
• Iatrogenic: ligation of ureter during ovariohysterectomy, complication after surgical correction of ectopic ureter, complication after neoureterostomy for renal tranplantation.
• Renal Kidney: neoplasia , ureteral Ureter: neoplasia , bladder Bladder: neoplasia or retroperitoneal neoplasia.
• Trauma.
• Ectopic ureter Ureter: ectopic.
• Intraluminal blood clot within renal pelvis or ureter Kidney: thromboembolism.
• Congenital ureteral stricture.
• Retroperitoneal fibrosis.
• Ureterocele Ureterocoele.
• Urinary tract infection.

Pathophysiology

• Obstruction at level of the renal pelvis or ureter → obstruction of normal urine flow → back pressure on kidney and ureter → dilation of renal pelvis and ureter proximal of obstruction → initially decrease in functional glomerular filtration rate → followed by structural damage to the affected kidney.
• Stasis of urine → predisposes to urinary tract infection and urolithiasis (especially struvite).
• Urinary tract infection → disruption of normal ureteric peristalsis.
• Increased renin production by acutely obstructed kidney → hypertension (not in chronic cases).

Timecourse

• Complete failure of the kidney once complete obstruction has been present for 4 weeks.

Diagnosis

Treatment

Outcomes