EFFECT OF ELECTIVE PROLONGED URETHRAL CATHETERIZATION ON SERUM PROSTATE-SPECIFIC ANTIGEN CONCENTRATION

Objectives, To determine the effect of an indwelling catheter on prost ate-specific antigen (PSA) levels. PSA is an organ (prostate)-specific marker, and its level can be elevated in various pathologies as well as following urologic manipulations. An elevated marker may indicate t he presence of prostate cancer. In the presence of an indwelling cathe ter, our inability to decide whether an elevated PSA value represents genuine pathology or is related to the catheter itself is often of gre at clinical importance. Methods. A prospective study was conducted on 21 men with an indwelling catheter inserted electively for major nonur ologic abdominal surgery to determine its influence on PSA concentrati on. Sera were collected before catheter insertion, 2 hours after, and then every day(average, 16 days). Catheters were left in place for an average of 5.5 days. Results. Follow-up data compared to baseline and to the previous day's PSA concentrations revealed no significant chang e in any of the subjects. In 2 men with elevated preinsertion PSA leve ls (more than 10.0 ng/mL), the change over time did not differ in magn itude from changes in the other 19 men with normal pretreatment values . Conclusions. Inserting a urethral catheter and maintaining it for se veral days does not result in any clinically or statistically signific ant change in PSA levels. PSA values obtained in patients with an indw elling catheter are reliable and independent of its presence. An eleva ted level mandates prompt evaluation to exclude prostate cancer.