Recurrent Diverticulitis Complicated by Colovesicular Fistula and Multiloculated Abscesses Formation: A Bounce-Back Case Emphasizing Diagnostic Pitfalls and Multidisciplinary Management

Diverticulitis complications, though rare, carry high morbidity. We present a 64-year-old male patient with multiple comorbidities who returned to the emergency department (ED) 27 days following hospital admission for acute diverticulitis with recurrence of the same, now complicated by colovesicular fistula, prostatitis, and multiloculated abscesses despite initial antibiotic therapy. Initial exam findings of tachycardia, and an appreciated boggy and severely tender prostate prompted timely/aggressive diagnostics and treatment. Computed tomography (CT) with intravenous (IV) contrast revealed a 6.6 cm prostatic abscess, 4.6 cm bladder abscess, and colovesicular fistula ultimately requiring Interventional Radiology drainage, broad-spectrum antibiotics, and urosurgical intervention. Cultures grew polymicrobial flora, including <i>Klebsiella</i> and <i>Pseudomonas</i>. This case underscores the need for early imaging in diverticulitis with urinary symptoms, multidisciplinary coordination for complex abscesses, and antibiotic stewardship in bounce-back patients. Emergency physicians must consider fistulae in high-risk populations to prevent delayed diagnosis or disease complications. Obtaining CT imaging with IV contrast early in patients who present with known diverticulitis in combination with acute urinary symptoms is important.