EMG sometimes shows myotonia-like discharges. Lipid is stored in muscle fibers and, in the latter disorder, myoglobinuria is a complication. Cases have been reported which are diet or steroid responsive. There are perhaps five known cases in the Northeast. CPK is often very high before EMG or biopsy changes are seen.
Hypothyroidism often produces muscle stiffness, muscle hypertrophy and aching.
1000U. Steroid induced myopathy, either iatrogenic or associated with Cushing's disease, results in proximal myopathy. Infection of muscle by Trichina or by viral agents produces a picture of pain and weakness. Polymyositis or dermatomyositis may produce pain along with weakness, but no infectious agent can be demonstrated. Dermatomyositis is sometimes associated with carcinoma in adults.