Acute bacterial prostatitis and abscess formation

Background: The purpose of this study was to identify risk factors for abscess formation in acute bacterial prostatitis, and to compare treatment outcomes between abscess group and non-abscess group. Methods: This is a multicenter, retrospective cohort study. All patients suspected of having an acute prostatic infection underwent computed tomography or transrectal ultrasonography to discriminate acute prostatic abscesses from acute prostatitis without abscess formation. Results: A total of 31 prostate abscesses were reviewed among 142 patients with acute prostatitis. Univariate analysis revealed that symptom duration, diabetes mellitus and voiding disturbance were predisposing factors for abscess formation in acute prostatitis. However, diabetes mellitus was not related to prostate abscess in multivariate analysis. Patients with abscesses <20 mm in size did not undergo surgery and were cured without any complications. In contrast, patients with abscesses >20 mm who underwent transurethral resection had a shorter duration of antibiotic treatment than did those who did not have surgery. Regardless of surgical treatment, both the length of hospital stay and antibiotic treatment were longer in patients with prostatic abscesses than they were in those without abscesses. However, the incidence of septic shock was not different between the two groups. A wide spectrum of microorganisms was responsible for prostate abscesses. In contrast, Escherichia coli was the predominant organism responsible for acute prostatitis without abscess. Conclusion: Imaging studies should be considered when patients with acute prostatitis have delayed treatment and signs of voiding disturbance. Early diagnosis is beneficial because prostatic abscesses require prolonged treatment protocols, or even require surgical drainage. Surgical drainage procedures such as transurethral resection of the prostate were not necessary in all patients with prostate abscesses. However, surgical intervention may have potential merits that reduce the antibiotic exposure period and enhance voiding function in patients with prostatic abscess.