Treating Elevated PSA with Antibiotics

Health Professional

A common reason to see the urologist is for an elevated PSA, or prostate specific antigen. A man's PSA can rise for a number of reasons. Inflammation or infection of the prostate, prostatic enlargement and, of course, cancer of the prostate are the most common causes of an elevated PSA.

A recent study from Palermo Italy reviewed the findings of PSA reduction after administering a 3 week course of an antibiotic. In their study, 99 men received ciprofloxacin for 3 weeks. 59 of the 99 men saw a reduction in their PSA. 40% of the 99 men had prostate cancer discovered by a prostate biopsy when the PSA did not change. 20% of the 99 men had prostate cancer discovered by a prostate biopsy when the PSA decreased. Importantly, no cancer was found if the PSA fell below 4.0 ng/ml or the PSA decreased by 70% of its initial value. The urologists concluded that a prostate biopsy can be postponed if the PSA decreases by more than 70% of its initial value or below 4.0 ng/ml. This postponement will allow a low risk of missing a cancer of the prostate.

It is common for a urologist to treat a man with an elevated PSA with a trial of an antibiotic. Statistically, it is more likely that a rise in PSA is caused by prostate inflammation than prostate cancer. A boggy or soft prostate examined during the consultation can clue the urologist that an elevated PSA is from inflammation or infection. Commonly, men do not have any symptoms that this inflammation is occurring. However, an abnormal prostate exam or a high index of suspicion should steer the urologist to performing a prostate biopsy ensuring that a cancer is discovered early.

There is a concern that urologists over-biopsy men with an elevated PSA. In other words, should every man referred to the urologist for an elevated PSA have a prostate biopsy? A prostate biopsy is an office-based procedure using ultrasound guidance that takes 15 to 20 minutes to perform. Although it is invasive, it has some minor side effects such as infection, bleeding and pain. This study demonstrates that a number of men have undiagnosed and asymptomatic prostate inflammation causing an elevated PSA. A reduction of the PSA after antibiotics can postpone or even prevent men from having an invasive test. Treating these men with a trial of antibiotics can help reduce the number of unnecessary prostate biopsies.

One thing I tell my patients is that I treat people, not numbers. Treating men with an elevated PSA is to some extent an art. Every man is different and the urologist should treat each man uniquely. A PSA of 4.1 ng/ml after antibiotics is very different in a man who is 49 years-old with a family history of prostate cancer compared to a 65-year-old man with a history of chronic prostatitis.