Which test is most appropriate for the initial evaluation of a patient suspected of acute prostatitis?

The most appropriate test for the initial evaluation of a patient suspected of acute prostatitis is urinalysis and urine culture. This is because acute prostatitis is often accompanied by urinary symptoms, including dysuria, frequent urination, and urinary obstruction.

Urinalysis helps identify the presence of white blood cells, bacteria, and other indicators of infection in the urine, which can suggest that prostatitis is present. A urine culture is critical for confirming the presence of specific pathogens responsible for the infection and determining the most effective antibiotic treatment.

While other tests may be used in different contexts, they are not as specific or helpful in the immediate assessment of acute prostatitis. For instance, prostate-specific antigen (PSA) testing can be affected by various conditions and is not specifically indicative of prostatitis. Scrotal massage may not only be uncomfortable but is also not a standard initial diagnostic tool for prostatitis. A complete blood count (CBC) with differential can provide information about the overall systemic response to infection but does not specifically diagnose prostatitis or identify the causative agent.

Thus, urinalysis and urine culture are the most direct and reliable approaches for evaluating patients suspected of acute prostatitis.