Characteristics of protein excretion in patients with acute urinary retention

Objective To evaluate changes in protein leakage in the glomerular filtrati on barrier, and in the ability of the tubule to reabsorb proteins during an d after acute urinary retention (AUR). Patients and methods Glomerular and tubular function was investigated in 24 men during AUR (mean age 68 years, mean retention time 31 h and mean reten tion volume 1140 mL) who were then followed for 6 months by measuring the u rinary excretion of glomerular and tubular proteins, and the glomerular fil tration rate (GFR). Retention was relieved by inserting a suprapubic cathet er and the cause of retention treated one month later. No patient had a pre vious renal disease or diabetes. Results During AUR, and after 1 and 6 months, albuminuria was detected in 1 00%, 92% and 54% of patients, and increased excretion of alpha1-microglobul in in 52%, 36% and 58%, of IgG in 79%, 58% and 40%, and of IgG4 in 67%, 42% and 20%, respectively. The mean GFR was normal during retention and during the follow-up. Conclusion AUR causes disturbances in both the glomerular filtration and tu bular reabsorption of proteins. Albuminuria and increased excretion of IgG, IgG4 and alpha1-microglobulin occurred in most patients during AUR. After relieving retention, the albuminuria and elevated alpha1-microglobulin excr etion persisted, indicating slight glomerular dysfunction and a permanent d efect in the proximal tubule to reabsorb proteins. This could be caused par tly by previous chronic obstruction. AUR should be relieved immediately and the basic cause treated effectively to prevent further deterioration of re nal function.