A 30-year-old man with a recurrent febrile illness resembling infection is described. Because he presented with an acute abdomen, he underwent a laparotomy, which showed the paraaortic and mesenteric lymph nodes to be changed into an abscess-like granulomatous tissue made up of necrotized granulocytes. During further flare-ups, the disease affected the spleen, skin, colon, peripheral nerve, and muscle. Histology on the biopsy materials of both the skin and colon, and on the surgically removed spleen showed the same invading pathologic tissue. Exhaustive investigation disclosed no pathogen, and the flare-ups responded repeatedly to high-dose steroids. This patient's picture has recently been defined as a syndrome of chronic granulomatosis based on several published cases. As a distinctive feature, in our patient the granulomas affected also the colon. For the present, and for another previously described similar case we analyzed the factors that might permit the differential diagnosis between the above-mentioned granulomatous syndrome and Crohn's colitis.