title: Macro-creatine kinase: a neglected cause of elevated creatine kinase.
abstract: Macro-creatine kinase (macro-CK) is a neglected cause of raised CK. Over a 10-year period, we observed five cases. Three patients had macro-CK type 1. One patient with fibromyalgia underwent several explorations to find a muscular pathology; another, who had elevated CK-MB (muscle-brain fraction) activity, was referred to a cardiologist, and statin therapy was erroneously discontinued in two patients. Two patients had macro-CK type 2: a man with a neuroendocrine carcinoma and a woman with rheumatoid arthritis. Diagnosis of type 1 obviates the need to carry out pointless and expensive investigations seeking a neuromuscular or cardiac pathology, and also, the unwarranted discontinuation of statin therapy. Type 2 must prompt investigations for a neoplasm.
authors.affiliation: Department of Rheumatology, G. Montpied Hospital, Clermont-Ferrand University, Clermont-Ferrand, France.
authors.forename: F
authors.initials: F
authors.lastname: Aljuani
authors.forename: A
authors.initials: A
authors.lastname: Tournadre
authors.forename: S
authors.initials: S
authors.lastname: Cecchetti
authors.forename: M
authors.initials: M
authors.lastname: Soubrier
authors.forename: J J
authors.initials: JJ
authors.lastname: Dubost
mesh_terms: D000368:Aged; D003402:Creatine Kinase / Q000032:analysis* / Q000378:metabolism*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D063806:Myalgia / Q000175:diagnosis* / Q000201:enzymology*
chemical_list: D003402:Creatine Kinase
keywords: creatine kinase; inflammatory myositis; macro-CK; neoplasm