Changes in serum prostate-specific antigen after treatment with antibiotics in patients with lower urinary tract...

Many urologists have performed prostate biopsy in men with a high level of prostate-specific antigen (PSA) alone. However, high levels of PSA may be induced by infection. We studied the effects of antibiotics on serum total PSA and PSA density (PSAD) in men with total PSA between 4 and 10 ng/ml and normal digital rectal examination (DRE) and transrectal sonographic findings.

From January 2005 to October 2009, a total of 107 patients with complaints of lower urinary tract symptoms (LUTS) or benign prostatic hyperplasia (BPH) were evaluated. To be included in this study, patients had to be at least 50 years old, have a palpably normal DRE, have infection in the prostate, have a total serum PSA of 4 to 10 ng/ml, and have transrectal ultrasound findings that did not show a hypoechoic lesion in the prostate. Only patients in whom the PSA level was rechecked after short-term antibiotics administration (8 weeks) were included. Serum PSA and PSAD were measured before transrectal ultrasound or EPS and after 8 weeks of treatment with antibiotics (quinolone). Age, prostate volume, serum PSA, PSAD, and PSA rate of change were compared.

The mean age of the patients was 66.3 years. The mean prostate size was 48.8±24.9 g. Forty patients had a high level of PSAD. Total PSA and PSAD significantly decreased after treatment (p<0.05). In 45 of the 107 men, total PSA after antibiotics treatment was normalized (less than 4 ng/ml). PSAD after treatment was normalized (less than 0.15 ng/ml/cm(3)) in 23 of the 40 patients with a high level of PSAD.

Antibiotics treatment for at least 8 weeks in BPH patients with an increased PSA level (4-10 ng/ml), infection, and normal DRE and transrectal sonographic findings may decrease serum PSA significantly. However, because the PSA level was not decreased to the normal range (less than 4 ng/ml) in all patients, it seems that antibiotics therapy before prostatic biopsy is not necessary.