Creatine kinase elevation in creutzfeldt-jakob disease

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.

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.

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.