Kveim reaction [Morton A. Kveim, Norwegian physician, b. 1892; L, re, again, agere, to act] , a reaction, used in a diagnostic test for sarcoidosis, to an intradermal injection of antigen derived from a lymph node known to be sarcoid. If a noncaseating granuloma appears on the skin at the test site in 4 to 8 weeks, the reaction is said to be positive evidence that the patient has sarcoidosis.
