A case of steroid induced myopathy and peripheral polyneuropathy in patient with iatrogenic Cushing syndrome / 대한내과학회지

ABSTRACT

Myopathy is a well known side effect of corticosteroid therapy. We report a case of iatrogenic steroid therapy induced myopathy in a 79-year-old female who had taken steroids for more than three years due to treatment for degenerative osteoarthritis. She complained of severe proximal muscle wasting and lower extremities weakness. Also, she had typical features of Cushing syndrome such as moon face, buffalo hump and easy bruising. Needle electromyogram showed no abnormal spontaneous activities in both lower extremities, but peripheral nerve conduction study showed motor conduction defect of both deep peroneal and tibial nerves. And, low SNAP (sensory nerve action potential) of both superficial peroneal and sural nerves, which were compatible with peripheral polyneuropathy in both lower extremities. The muscle biopsy revealed a pronounced muscle fiber atrophy, fatty degenerative change and selective type 2 fiber depletion on ATPase staining in pH 9.4 buffer. She was treated isotonic exercise physical therapy and slowly improved. After three months later, she complained sudden onset of chest discomfort and died due to congestive heart failure.