The authors report on a woman (34 years old) which was affected by lymphomatoid granulomatosis. During the first periods of the disease the granulomatous lesions were confined to the muscles of the upper extremities. High fever, progressive development of new muscular lesions and later of lesions in the pharynx, larynx, and the lungs characterized the clinical course. Therapeutic approaches included glucocorticoids, chemotherapy, irradiation, plasmapheresis, but induced no relevant beneficial effect. Based on laboratory and experimental data as well as on data from the literature the authors discuss the pathogenesis and differential diagnosis of this disorder.