[Macromolecular creatinine kinase in patients diagnosed with ulcerative colitis]

Macromolecular creatinine kinase (macro-CK) type 1 is a macroenzyme formed by the union of an immunoglobulin with a creatinine kinase (CK) enzyme. Its presence in the blood may lead to misdiagnosis of heart disease. This macromolecule has been described in various diseases and is relatively more frequent those with autoimmune etiology. We describe three cases of ulcerative colitis that presented elevated MB-isoenzyme of CK activity greater than the total CK quantified by the immunoinhibition method. Electrophoresis revealed an atypical band that corresponded with the presence of a type 1 macroenzyme. Detection of this macromolecule could be useful in cases of ulcerative colitis when results of blood testing lead to suspicion of ischemic disease.