A 32-year-old man presented with 3-weeks history of abdominal pain and distention. Physical examination showed ascites, with no stigmata of chronic liver disease. Cytological preparations from the ascitic fluid showed a heavy population of mature eosinophils. Histological examination of colonic biopsies revealed a heavy expansion of the mucosa by sheaths of eosinophils. On the following days, the peripheral eosinophilia, ascites and abdominal pain resolved spontaneously.