Creatine kinase elevation in creutzfeldt-jakob disease.

Objective: Creutzfeldt-Jakob disease (CJD) is not only a disorder of the central nervous system but also affects the skeletal muscle. Subclinical skeletal muscle involvement, manifesting as hyper-creatine-kinase (CK)-emia, is rare.

Methods: The patient, a 60-year-old male, developed progressive dementia, accompanied by dysphagia and bursts of aggression, disorientation and optic hallucinations. Five months after onset of the cognitive decline, hyper-CK-emia of 117 U/l (normal: <81 U/l) was noted for the first time. During 12 months until decease, hyper-CK-emia was permanently present and reached a maximum of 354 U/l. Hyper-CK-emia was attributed to subclinical involvement of the skeletal muscle in CJD. Hyper-CK-emia due to progressive brain damage, double trouble of an additional primary myopathy or due to excessive myoclonic jerking was excluded.

Conclusions: This case shows that CJD may be present with mild hyper-CK-emia in individual patients, most likely due to concomitant undiagnosed involvement of the skeletal muscle in the primary disease.