Rheumatologic complications of vitamin A and retinoids.

Retinoids are synthetic derivatives of vitamin A. They are administered primarily for dermatological conditions, such as psoriasis, acne, and disorders of keratinization. Toxicity has proven a significant problem with long-term administration of the retinoids.

Drug-related myopathies.

Myopathies produced by drugs are of vital concern and often confused with other more frequently diagnosed causes, such as the inflammatory myopathies of polymyositis/dermatomyositis and myositis secondary to toxic agents, metabolic and endocrine abnormalities, genetic predisposition, malignancies, and infections, particularly viruses. The drug-induced causes of myopathy warrant special emphasis because they are often overlooked, resulting in misdiagnosis and improper care.

Heart disease in systemic sclerosis.

Primary cardiovascular manifestations of SSc include pericardial disease, myocardial disease, conduction abnormalities, and cardiac arrhythmias. Significant cardiac abnormalities are present in more than half of SSc patients at autopsy. As the frequency of subclinical cardiac involvement is now appreciated and noninvasive cardiac diagnostic modalities continue to improve, the ability to detect early asymptomatic involvement in SSc has improved.