“原発性”大腸結核症の1例

Primary Colonic Tuberculosis, Report of a Case

はじめに

Crohn病の肉芽腫に極めて類似した非乾酪性肉芽腫を内視鏡下大腸粘膜生検にて認めた“原発性”大腸結核症を経験したので報告する．

　A 34-year-old woman visited our hospital because of ileocecal pain and mass. Chest x-ray showed normal lung fields, and no infiammatory signs were found in laboratory examination. Barium enema study revealed marked deformity and narrowing limited to the ascending colon with multiple irregularly-shaped shallow ulcers. Endoscopic examination revealed circular ulcers and inflammatory polyps scattered in the ascending colon, Biopsy specimen obtained from normal appearing mucosa adjacent to the ulcers showed a tiny non-caseating epithelioid cell granuloma which closely resembles to those of Crohn's disease.

Eight weeks iater, however, tubercle bacilli were cultured and identified from the biopsy specimen taken from the ulcer bed. Antituberculosis chemotherapy was started with definitive diagnosis of colonic tuberculosis. In five weeks after the chemotherapy was instituted, remarkable improvement of the colonic lesion was confirmed by radiological and endoscopical studies.

　Generally, histological findings in biopsy specimen are not always diagnostic of intestinal tuberculosis: it is rare to find typical caseating granuloma, while it is not rare to find non-caseating granuloma in biopsy specimen. Furthermore, non-caseating granulomas are not necessarily specific to Crohn's disease. In cases of primary intestinal tuberculosis, therefore, careful radiologic and endoscopic analyses are more important in making the definitive diagnosis than histological findings.