Observations on the Kveim reaction using an animal model of granulomatous bowel disease.

Striking differences were observed between the visceral and cutaneous responses after tests with validated Kveim and normal spleen suspensions in a guinea pig model of granulomatous bowel disease. Five of six animals sensitised with BCG showed positive responses at the ileal Kveim test site whereas all six had negative cutaneous Kveim tests. Conversely, two of six animals sensitised with irradiated Mycobacterium leprae showed positive cutaneous Kveim tests and only one a positive response in the ascending colon. All six showed negative responses at the ileal Kveim test site. No positive visceral or cutaneous responses were observed in either group of animals after tests with normal spleen suspension. These findings are discussed in relation to the positive Kveim responses previously reported among patients with Crohn's disease, tuberculoid and lepromatous leprosy, and among seemingly healthy BCG vaccinated subjects. The findings provide further evidence in support of a possible mycobacterial aetiology for sarcoidosis and Crohn's disease.