A transrectal ultrasound-guided prostate biopsy is a surgical procedure used to obtain tissue cores in order to diagnose or exclude the presence of cancer. As such, the technique carries its own risks such as infections, bleeding, allergic reactions, but also some other potential complications.
Approximately 1.7% of patients develop infections in the biopsy area, perhaps because infectious organisms are transmitted through the biopsy track. Prophylactic antibiotics are prescribed to keep this risk low. The risk is higher (2%) after a transrectal biopsy as compared to a transperineal procedure (1%). Men who had prostatitis also have a higher chance of infection. Symptoms include fever, pain or a burning feeling during urination. These should be promptly reported to the doctor.
Infectious complications include asymptomatic bacteriuria (transient, in about 5%), urinary tract infection (2-3%), fever with urinary infection, and sepsis. The rate of infection serious enough to require hospital admission following prostate biopsy appears to be on the rise.
High-risk patients may be identified by taking a history of antibiotic use in the 6-month period before the prostate biopsy is performed. These men may be given antibiotics based on the results of a rectal swab culture, or predefined broad-spectrum antibiotics.
Other high-risk groups include hospital employees as well as their families, because they may be infected with multi-drug resistant organisms. International travelers may have received broad-spectrum or inappropriate antibiotics in other countries, leading to drug resistance and ineffectiveness of conventional antibiotic prophylaxis. A history of prior prostate biopsy also inevitably is linked with previous antibiotic intake, pushing up the risk of post-biopsy infection with resistant organisms.
The most serious potential infectious complication is the introduction of bacteria from the rectum into the bloodstream with subsequent sepsis. For such patients the treatment should be tailored according to the resistance profiles of the local region, the culture and susceptibility reports, but also patient's medical history.
Hematuria and bleeding episodes
In just less than half of patients, hematuria persists for more than a few days, from light discoloration to frank blood. In most cases, it is transient and does not require treatment. Patients should be advised to drink extra fluids to increase the urine output and flush out the blood. Hematuria is not related to the use of anti-platelet agents or NSAIDs. Heavy and persistent bleeding that occurs with every episode of urination should be evaluated by a doctor.
Rectal bleeding is reported in 6% of biopsy patients, occurring in the first two or three days following the procedure. In the vast majority of cases, it should fade out in a couple of weeks at most. Heavy bleeding, especially associated with the passage of clots, should arouse concern and needs to be reported to the doctor.
Blood may appear in the semen on ejaculation for up to 6 weeks, though in a few men it may continue to appear for longer periods. This side-effect is mostly self-limiting, although it can be associated with a certain degree of anxiety and impact on sexual activity.
Urinary clot retention
About 2-5% of patients report that they have difficulty in voiding following a biopsy. This is often because of internal bruising of the urethra or the bladder, leading to urinary clot retention. This causes swelling and obstruction of the urinary passage, or (in a few patients) it may produce frequency or urgency of urination.
Urinary clot retention is more likely to appear in patients who already had difficulty before the biopsy. This symptom should be reported to the doctor, as some of these patients may require catheterization to prevent retention of urine.
Allergic reactions and other side-effects
The drugs used during the biopsy procedure may, as with any medication, cause an allergic reaction, though this is rare, occurring in less than 0.01% of patients. Patients should always inform their doctors of any previous hypersensitivity reactions they have had to food or medications.
Furthermore, the perineal region may hurt for up to a week, though not significantly. This is more likely to be the case in younger patients, irrespective of the number of biopsy punctures actually made.
A TRUS biopsy may also leave the patient feeling dizzy, especially if he/she is in the fasting state. If it was done under general anesthesia, the resulting generalized ache or feeling of weakness may last for a day or two. Thus patients should arrange for someone to take them home and stay with them during this period.
Reviewed by: Dr Tomislav Meštrović, MD, PhD