1996 Volume 29 Issue 8 Pages 1812-1815
A case of omental actinomycosis caused by perforation by a fishbone is reported. A 62-year-old woman was admitted complaining of an abdominal mass. A firm, fixed mass measuring 15 cm in diameter was palpated in the right lower quadrant of the abdomen. Barium enema study revealed serrated changes in the transverse colon. Computed tomography showed a nonhomogeneous mass adherent to the transverse colon. Laparotomy was performed under a diagnosis of omental tumor. An inflammatory tumor of the omentum involving the transverse colon and the stomach was removed by partial resection of the colon and the stomach. The resected specimen showed abscess formation around a fishbone, which was histologically diagnosed as actinomycosis. Six cases of abdominal actinomycosis caused by fishobones have been reported in Japan. In most of these cases, an abdominal mass was noted, and the fishbone was likely to perforate the lower intestinal tract. The correct preoperative definitive diagnosis was not made in any case. In conclusion, actinomycosis should be considered in the management of an abdominal mass of unknown origin.
