Observations on the Kveim reaction in sarcoidosis of the American Negro.

In 1941, Kveim (1) described the production of a cutaneous reaction in patients with sarcoidosis following the intracutaneous injection of heated saline suspensions of lymph glands obtained from active cases of that disease. The response, consisting of a small, brownish-red, indurated papule at the site of injection was remarkable for its slow evolution and its persistence. Characteristically, the reaction required weeks to attain its maximum size and thereafter usually remained visible for many months. Microscopic examinations of tissue from the reaction sites revealed a histological picture similar to that of spontaneously occurring sarcoid. Simultaneous control injections of Old Tuberculin and Frei antigen in the same patients gave no comparable response. Conversely, the sarcoid material yielded negative results when administered intracutaneously to normal individuals and to persons with syphilis or lupus vulgaris. From these findings, Kveim concluded that this was a specific reaction for sarcoidosis, and that it probably was allergic in nature . Several reports extending and, for the most part, confirming Kveim's initial results have recently been published in the Scandinavian countries (2), (3), (4), (5), (6). In one sense these studies seem to indicate that the specificity of the Kveim reaction is relatively high, since positive results in conditions other than sarcoidosis have been encountered only rarely (2), (4), (5). In another sense, however, the specificity of the Kveim reaction has remained in doubt because complete data on the skin reactivity of sarcoid patients to the intracutaneous administration of different human tissue suspensions are lacking. Indeed, it has been shown that a reaction similar to that described by K veim may be observed occasionally in cases of sarcoidosis following the intracutaneous injection of such substances as suspensions of leukemic human lymph nodes (5) and killed tubercle bacilli (7), (8). These findings suggest the possibility that the Kveim reaction, rather than being a specific phenomenon, may be a general tissue response on the part of individuals with sarcoidosis to a number of different substances. An opportunity to investigate this phase of the problem in some detail was presented during the course of a recent study of sarcoidosis in the American Negro (9). While there is no conclusive evidence that the disease in the Negro differs essentially from that found in other races, it is tme that the cutaneous lesions of sarcoid exhibited by the Negro are consistently of the annular, papular type. The diffuse, plaque-like, lupus pernio skin lesions commonly observed in white individuals are rarely found in Negroes. In its other manifestations, however, the disease does not seem to be significantly