Case Report: Psoas abscess caused by Carbapenem-Resistant Enterobacteriaceae in a CO poisoning patient.

A 69-year-old Chinese male farmer suddenly developed severe lower back pain accompanied by persistent high fever during his recovery from carbon monoxide (CO) poisoning. Clinical examination revealed limited spinal mobility and significant tenderness in the L2-L4 vertebrae and bilateral paravertebral regions, with no palpable masses. Magnetic resonance imaging (MRI) showed fluid accumulation around the bilateral psoas muscles, confirming the presence of bilateral abscesses. We performed ultrasound-guided puncture and drainage of the affected area, and the culture of the drainage fluid identified Carbapenem-Resistant Enterobacteriaceae (CRE). The final diagnosis was bilateral primary psoas abscess (PPA), and targeted antimicrobial therapy for CRE infection was initiated.