[Macro-creatine kinase; circulating immunoglobulin enzyme complexes as cause of elevated CK-activities (author's transl)].

We report a case of a woman (58 years old) with persistent and elevated CK activities and without corresponding clinical signs. For seven months CK-B activity was determined above normal by an inhibition test. By exclusion chromatography, ion-exchange chromatography, electrophoresis of CK isoenzymes and immunological methods we were able to explain this phenomenon as Macro CK consisting of immunoglobulin G bound CK-BB.