Total and free serum prostate specific antigen levels during the first month of acute prostatitis

Abstract

Objectives: The level of total prostate specific antigen (PSA) rises in acute prostatitis. The PSA fraction responsible for this increase and the evolution of the free/total PSA ratio are little known at the present time. We therefore carried out a prospective study of the evolution of total and free PSA levels and the free-to-total PSA ratio for one month after diagnosis of acute prostatitis.

Patients and methods: Between January 1999 and February 2001, 31 consecutive patients (mean age 51 years) were treated for acute prostatitis. No patient had a history of prostate cancer or of recent prostatitis. Measurement of C-reactive protein (CRP), total PSA and free PSA was done at days 0, 3, 10 and 30.

Results: During the first month of acute prostatitis and under an adapted antibiotherapy, CRP progressively decreased and returned to normal levels at about day 10. Total PSA level increased up to day 3 and then gradually decreased until at least the end of the first month. The level of free PSA decreased up to day 10 and was still low at one month, leading to a decrease in the free-to-total PSA ratio which was reached its lowest level at day 10 and was still low at one month.

Conclusion: The increased level of total PSA in acute prostatitis is secondary to the proportional increase in bound serum PSA and decrease in free PSA. Free PSA was still low at one month, maintaining a low free-to-total PSA ratio.