Proteinuria and renal function during and after acute urinary retention

Purpose: Benign prostatic hyperplasia is the most common neoplasm as well as the main cause of bladder outlet obstruction in men. It may progress to involve a risk of urinary retention. We investigated the effects of acute urinary retention on renal function. Materials and Methods: We evaluated renal function using biochemical markers in 25 men with a mean age of 69 years in whom an episode of acute urinary retention a mean of 31 hours in duration was due to bladder outlet obstruction. Patients were followed for 6 months after acute retention was relieved. Patients were not known to have had any renal disease previously. Results: During acute urinary retention at presentation, and after 1 and 6 months we noted albuminuria in 100, 92 and 54% of patients, elevated alpha 1-microglobulin excretion in 54, 39 and 58%, and elevated beta 2-microglobulin excretion in 17, 19 and 9%. Serum creatinine or creatinine clearance did not predict proteinuria. All parameters became normal at 6 months in only 2 cases. Conclusions: Acute urinary retention affects glomerular and tubular renal function. After acute urinary retention was relieved increased glomerular permeability and tubular damage persisted in the majority of patients. This condition may have been partially due to previous long-term bladder outlet obstruction. Our findings stress the importance of the rapid recognition and treatment of acute urinary retention.