Severe Bacteremia Caused by Clostridium butyricum Following Endoscopic Ultrasound-Guided Peripancreatic Fluid Drainage for Walled-off Necrosis: A Case Report.

We report a rare case of bacteremia caused by Clostridium butyricum following endoscopic ultrasound-guided peripancreatic fluid drainage (EUS-PFD) for walled-off necrosis (WON) in a patient with alcoholic chronic pancreatitis. The patient underwent EUS-PFD using a plastic stent (PS) for WON, initially with a good response. However, dislodgement of the PS resulted in closure and secondary cavity infection. The patient subsequently developed sepsis and multiorgan failure. Blood cultures from arterial and venous sources confirmed C. butyricum, consistent with the patient's oral intake of C. butyricum MIYAIRI 588 (CBM 588). Intensive care, including repeated EUS-PFD and antibiotic administration, led to recovery. Although CBM 588, a C. butyricum agent, remains a valuable probiotic, clinicians must exercise caution when prescribing it to patients with impaired mucosal barriers or those undergoing EUS-guided drainage procedures. Close monitoring of stent placement, drainage efficacy, and individualized assessment of probiotic administration are essential to minimize the risk of systemic infections. Trial Registration: The authors have confirmed clinical trial registration is not needed for this submission.