Clinical Characteristics and Diagnostic Pathways of Emphysematous Cystitis in a University Hospital: A Retrospective...

Emphysematous cystitis (EC) is an uncommon but clinically important form of complicated urinary tract infection characterized by gas within the bladder wall and/or bladder lumen. Because EC may present with urinary symptoms, nonspecific systemic symptoms, or incidental computed tomography (CT) findings, its diagnostic process in tertiary hospitals remains clinically relevant. This study aimed to describe the clinical characteristics, diagnostic pathways, microbiological findings, treatment, and outcomes of EC in a university hospital.

We retrospectively reviewed 45 patients diagnosed with EC based on abdominal CT findings at Teikyo University Hospital between October 2010 and March 2024. Data on clinical presentation, comorbidities, microbiological findings, treatment, and clinical outcomes were extracted from electronic medical records.

A total of 45 patients were analyzed, including 25 males and 20 females, with a median age of 79 years (range: 31-97 years). Diabetes mellitus was present in 21 patients. The most frequently detected urinary pathogens were Escherichia coli (n = 21), including extended-spectrum β-lactamase-producing strains (n = 7), and Klebsiella pneumoniae (n = 9). In blood culture, K. pneumoniae (n = 7), E. coli (n = 5), including extended-spectrum β-lactamase-producing strains (n = 2), and Staphylococcus epidermidis (n = 2) were detected. Most patients were managed conservatively; urinary catheter placement was performed in 35 patients. Regarding EC treatment outcomes, 34 patients recovered or improved, 10 died during the clinical course, and 1 had an unknown or unclear outcome. No deaths were judged to be directly attributable to EC itself. Retrospective review of the clinical course leading to CT detection of EC suggested four diagnostic pathways.

EC occurred mainly in elderly patients with comorbidities and was frequently detected by CT in diverse clinical contexts. These diagnostic pathways are a descriptive summary of how EC was detected in this cohort, rather than a validated prognostic or treatment-guiding classification.