Postoperative Intra-Abdominal Clostridium tertium Infection Following Obstructed Obturator Hernia Repair: A Case Report and Literature Review.

Clostridium tertium is an emerging opportunistic pathogen typically associated with immunocompromised hosts, yet it can also cause serious infections in non-neutropenic individuals. We present a case of postoperative peritonitis and bacteremia caused by C. tertium in a non-neutropenic 75-year-old woman following emergency obturator hernia repair. Diagnosis was confirmed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), and successful treatment was achieved with piperacillin-tazobactam combined with levornidazole alongside surgical source control. A review of 128 cumulative cases (including ours) revealed two distinct patterns: bacteremia in severely neutropenic patients versus a broader spectrum of localized and bloodstream infections in non-neutropenic hosts, often linked to intestinal barrier disruption. Mortality was largely driven by underlying comorbidities and polymicrobial sepsis. These findings indicate that C. tertium infection should be considered in non-neutropenic patients with postoperative or gastrointestinal barrier-disruptive infections, especially when there is a poor response to initial empiric therapy. Consequently, in such clinical scenarios, empirical therapy should be guided by its unique resistance pattern, favoring carbapenems, vancomycin, or piperacillin-tazobactam, often combined with a nitroimidazole, alongside urgent source control.