Comamonas testosteroni in perforated appendicitis: a rare cause of intra-abdominal infection

Comamonas testosteroni is an uncommon environmental Gram-negative bacillus rarely implicated in human infections. We report a case of a 34-year-old male who presented with acute appendicitis complicated by a sealed perforation. Laparoscopic appendectomy was performed, and postoperative cultures identified C. testosteroni in the appendiceal tissue, alongside Pseudomonas aeruginosa and Streptococcus anginosus in the peritoneal fluid. Initial empirical antibiotics were escalated to piperacillin-tazobactam based on culture results. The patient recovered uneventfully and was discharged on postoperative day nine. This case highlights the emerging clinical relevance of C. testosteroni and the importance of microbiological evaluation in guiding management of perforated appendicitis.