A 50-year-old Caucasian man was admitted with unexplained abdominal pain. Based on CT scan results, a perforation resulting from colitis of the transverse colon was suspected. Additional colonoscopy showed ulcerative stenosis of the transverse colon. Initially, the patient recovered on conservative treatment; however, because of persistent stenosis, an elective resection of the transverse colon was performed. A CT scan revealed free gas around the anastomosis on the fourth postoperative day. Relaparotomy revealed leakage and diffuse ischaemic changes around the anastomosis as well as perforations at different sites on the small bowel. Postoperative CT angiography showed stenosis of the proximal celiac trunk, which was successfully stented. Digital subtraction angiography (DSA) revealed luminal irregularities of the superior mesenteric, the middle colic as well as the main hepatic and splenic arteries. Eventually, the clinical presentation and surgical, radiologic and histopathological findings together led to the diagnosis of polyarteritis nodosa (PAN). Aggressive treatment with glucocorticoids and cyclophosphamide resulted in the resolution of symptoms and the disappearance of radiologic abnormalities.