Myopathic complications of medical disease.

Disorders of muscle may be primary or acquired secondary to an underlying medical condition. Clinical presentations range from asymptomatic elevations in creatine kinase to fatal rhabdomyolysis. Recognition of the underlying precipitant is imperative to effectively institute treatment for a potentially reversible process. The focus of this article is to review complications of systemic illness that result in signs and symptoms of muscle dysfunction. Myopathic complications of endocrinopathy, metabolic abnormalities, medications, critical illness, organ transplantation, infection, autoimmune conditions, malignancy, and toxin exposure are discussed, with an emphasis on the clinical features, electromyography, and muscle biopsy findings.