Myositis as a Presenting Manifestation of Severe Hypothyroidism: A Case Report and Review of the Literature

Abstract

William M. Ord described the first case of muscle weakness with hypothyroidism in 1880 and subsequently it has been reported in several cases . Hypothyroid induced myositis is an inflammatory myopathy characterized by musculoskeletal symptoms which can be confirmed through increased serum level of muscle enzymes such as creatine kinase (CK) (up to 10 times normal), nonspecific electromyographic (EMG) abnormalities and pathological findings in muscle biopsies . Frequent symptoms include fatigue, proximal muscle weakness, myalgia, tenderness, and stiffness . Necrosis, inflammatory infiltrates, type II fiber atrophy, increased numbers of internal nuclei, and “core-like” structures in type I fibers are common findings in muscle biopsies [3, . Treatment of these patients consists of administration of thyroid hormone and in some cases also corticosteroids. It can take several months for the muscle symptoms to resolve [1, .