Pneumatosis intestinalis (PI) is a rare radiographic sign characterized by gas-filled cysts within the subserosal and/or submucosal regions of the intestinal wall. The source of this gas and its translocation across the mucosa is incompletely understood. We report a case of pneumatosis coli in a patient with recurrent C-diff. A 58-y.o. female with history of type 2 DM, HTN, and ESRD presented to ER with 3-day history of severe abdominal pain, nausea, vomiting and watery diarrhea. She had constant peri-umbilical cramps. Diarrhea was 6-7 times per day, worse after eating, and without melena or hematochezia. Patient completed a course of oral vancomycin for C-diff diarrhea 3 weeks prior and her previous symptoms had resolved. Examination showed fever of 101 F, soft non-distended abdomen, hyperactive bowel sounds, tenderness to palpation above the umbilicus, and no guarding or rebound. Blood work was unremarkable with no leukocytosis. Lactic acid was normal. CT abdomen without IV contrast showed extensive pneumatosis coli involving the transverse colon with associated mesenteric and intrahepatic portal venous gas with no overt perforation, free air, or abscess (image1,2). C-diff was positive again for this admission. Patient was started on supportive therapy with aggressive fluid resuscitation, IV metronidazole and oral vancomycin. Surgery recommended medical therapy. Patient improved markedly and was discharged home to complete a course of oral vancomycin for recurrent C-diff. Supportive care and appropriate antibacterial agents sufficed to alleviate symptoms and resolve pneumatosis coli on repeat imaging (image 3). It is important to recognize that PI is a clinical sign and is, per se, not a diagnosis. About 85% of cases of PI are associated with variable medical conditions and 15% are idiopathic. Because it represents a wide spectrum of diseases, management of PI ranges from surgical intervention to outpatient observation. Since PI is infrequently encountered, clinicians may be unfamiliar with its diagnosis and management. This unfamiliarity, combined with the potential necessity for urgent intervention, may place the clinician confronted with PI in a precarious medical scenario.Recognizing this uncommon but important association can prevent high costs from unnecessary testing and invasive surgical explorations. We should consider pseudomembranous colitis as the cause of pneumatosis coli in patients who have received antibiotics, once gut ischemia is ruled out.1455_A Figure 1. CT abdomen without IV contrast shows extensive pneumatosis coli1455_B Figure 2. CT abdomen shows intrahepatic portal venous gas1455_C Figure 3. CT abdomen one month later