Evaluation of the Patient

The evaluation of the patient with inflammatory myopathy takes into account the history, physical findings, and ancillary examinations, including laboratory assessment, electromyography, imaging studies, and muscle biopsy. Weakness and its pattern of presentation are the cardinal features. Rash should also be evaluated, if present. Beyond these systems, the possibility of pulmonary, gastrointestinal, or cardiac involvement should be considered and vascular abnormalities, as well as calcification, noted. In active disease, elevation of the activities of certain enzymes in the serum (e.g., creatine kinase) and of serum myoglobin will reflect their loss from muscle tissue and may serve as guides to disease severity or course. Clinical evaluation of these elements, carried out in an ongoing manner, can be used to assess progress and response to therapy.