Polymyositis after propylthiouracil treatment for hyperthyroidism

• Published in: Annals of the rheumatic diseases Vol. 47; no. 4; pp. 340 - 343
• Main Authors: Shergy, W J, Caldwell, D S
• Format: Journal Article
• Language: English
• Published: England BMJ Publishing Group Ltd and European League Against Rheumatism 01.04.1988; BMJ Publishing Group LTD
• Subjects: Adult; Female; Humans; Hyperthyroidism - drug therapy; Muscles - pathology; Myositis - chemically induced; Myositis - pathology; Propylthiouracil - adverse effects; Propylthiouracil - therapeutic use
• ISSN: 0003-4967; 1468-2060
• DOI: 10.1136/ard.47.4.340

An additional disorder in the spectrum of thyroid related muscle disease is presented. Hypothyroid and hyperthyroid disease are both associated with a variety of muscle abnormalities, from myalgias to myopathy. Polymyositis, however, has never been reported immediately after treatment for active hyperthyroidism. A patient is presented with typical hyperthyroidism, who developed a severe proximal muscle weakness and a raised creatine phosphokinase after treatment for hyperthyroidism with propylthiouracil (100 mg orally, three times a day). Electromyography, muscle biopsy, and the course of the patient's illness were consistent with polymyositis. Whether this represents a cause-effect association or a chance occurrence is unknown. Physician awareness of the occurrence of a variety of muscle disorders including polymyositis in thyroid disease is emphasised. A brief discussion of thyroid myopathy, thionamide drug reactions, and polymyositis is included.