[The diangostic value of skin tests with tissue-extracts, especially in lepra and sarcoidosis (author's transl)].

The immunological aspects of lepra (India, Germany) and Sarcoidosis are presented under consideration of cutaneous reaction to lepromin and Kveim-extracts. Patients with lepra, erythema nodosum, sarcoidosis and different dermatoses have been tested with lepromin, Kveim-Antigen and tuberculin. The specifity of the results has been discussed. Patients with tuberculoid lepra did not react on Kveim-test, but patients with sarcoidosis can give positive reaction on lepromin. Patients with erythema nodosum without clinical signs of sarcoidosis are Kveim negativ and a positive lepromin-test is an exception. The positive Kveim-test is bound to a histological examination. The positive lepromin-test in non lepraendemic countries should be interpreted also by histological examination. Granulomatous dermatoses can show positive lepromin-tests, but the histological picture is different from the lepromin reaction in tuberculoid lepra. The positive reactions on tissue extracts are not combined with positive immunfluorescence results. Intracutaneous injection of lepra-bacilli in lepromin extract can be presented days to weeks after intracutaneous application in biopsies.