Differential diagnosis of serum creatine kinase elevation

Abstract

Routine blood chemistry profiles normally include measurements of creatine kinase (CK) activity. Therefore, an increasing number of patients with elevated creatine kinase levels are identified. General practitioners, anesthesiologists, surgeons and neurologists might be confronted with such an unexplained non-cardiac hyperCKemia. Although this problem is not uncommon, it has been the subject of only a few studies. We provide a clinical review of the enzyme CK in humans and of 343 case reports of idiopathic persistently elevated CK serum levels. At present, altogether nine studies provide retrospective data on patients admitted to neuromuscular centers for a work-up of idiopathic hyperCKemia and/or susceptibility to malignant hyperthermia. After complete examination, including a muscle biopsy, a subclinical myopathy could be delineated in up to 50% of the patients.