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, including infections, bleeding, allergic reactions, and other potential complications.
Infections
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 minimize this risk. The risk is higher (2%) after a transrectal biopsy as compared to a transperineal procedure (1%). Men with prostatitis also have a higher risk 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 (occurring in approximately 5%), urinary tract infection (2-3%), fever with urinary tract infection, and sepsis. The rate of infection severe 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 a predefined regimen of broad-spectrum antibiotics.
Other high-risk groups include hospital employees and their families, as they may be exposed to multidrug-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 is also inevitably 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, leading to sepsis. For such patients, treatment should be tailored according to the local region's resistance profiles, cultural considerations, susceptibility reports, and the patient's medical history.
Hematuria and bleeding episodes
In just less than half of the 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 antiplatelet agents or NSAIDs. A doctor should evaluate heavy and persistent bleeding that occurs with every episode of urination.
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, primarily associated with the passage of clots, should arouse concern and be reported to a doctor.
Blood may appear in the semen on ejaculation for up to 6 weeks, though in a few men it may continue to occur for more extended 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
Approximately 2-5% of patients report difficulty voiding after a biopsy. This is often due to internal bruising of the urethra or 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 occur in patients who already had difficulty prior to the biopsy. This symptom should be reported to a doctor, as some patients may require catheterization to prevent urinary retention.
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 men feeling dizzy, especially if they are fasting. If it was done under general anesthesia, the resulting generalized ache or feeling of weakness may last for one to two days. Thus, patients should arrange for someone to take them home and stay with them during this period.
Further Reading