Autopsy case report of rapidly progressive iliopsoas abscess caused by Escherichia coli and Prevotella bivia

Computed tomography-guided drainage or surgical drainage should be considered for psoas abscesses. Active surgical intervention is considered for gas-forming psoas abscesses; however, computed tomography-guided drainage may be selected, depending on the circumstances. In this case, Computed tomography was used to confirm the spread of the infection, but the autopsy revealed abscess formation outside the right pleural cavity, which was difficult to detect on computed tomography. <i>Prevotella bivia-</i>associated psoas abscesses are rare but have been previously reported. A 48-year-old male had been undergoing hemodialysis for 5 years for diabetic nephropathy. Contrast-enhanced computed tomography revealed large right-sided predominant abscesses involving the iliopsoas muscle, an abscess with pneumoperitoneum in the para-aortic region, increased density in the perirenal adipose tissue, additional abscess formation, and right empyema. Blood cultures grew <i>Escherichia coli</i>, whereas drainage fluid cultures produced <i>Escherichia coli</i> and <i>Prevotella bivia</i>. Despite treatment, improvement was minimal, and cardiac arrest occurred on the fourth day after transfer to our hospital.