Polyarteritis presenting with leg pains.

Polyarteritis (polyarteritis nodosa) is a multi-system connective tissue disorder involving small and medium-sized arteries throughout the body. Occasionally, however, the condition is clinically localized to a few systems, such as skin and muscle, and it appears that in these circumstances the disease often follows a relatively benign course (Rose, 1957; Rotstein and Good, 1958). In this paper three cases of polyarteritis are presented in which the initial and predominant symptoms were pains in the legs. In two patients the lesions were confined to the skin and muscles of the lower limbs, and in the third the arteritis appeared to be localized entirely to the leg muscles, a finding not previously described in the literature. CASE 1 For several years a 47-year-old Italian man had been subject to attacks of pain in altemate legs lasting for two to three days and usually associated with the appearance of a rash. When seen during the course of a typical attack he had a mild pyrexia (99-100lF.; 37 2-37-8' C.), tenderness on palpation of the calf mus-des, and an erythematous rash on the legs. The E.S.R. was 54num./hour (Westergren), and electrophoresis of serum proteins showed raised alpha-2 globulin. electrocardiogram-showed nothing abnormal. Biopsy of a skin lesion showed a subacute perivascular reaction in the dermis associated with some oedema. Polymorphs were frequent among the cells, and the appearance suggested polyar-teritis. Biopsy of a calf muscle was normal, as were the muscle serum enzymes, but electromyography showed changes consistent with a muscle fibre lesion. The symptoms were completely suppressed by prednisolone 22.5 mg. daily. When he attempted to reduce the steroid dose the pain recurred, but after some months it was possible to reduce to prednisolone 10 mg. and later 5 mg. daily without recurrence of pain. On this dosage he has been well to the date of follow-up, 18 months from the onset of symptoms. CASE 2 A 30-year-old male charge nurse had been affected by mild generalized "rheumatism" for some years. For the previous three months he had complained of gradually increasing pains in the legs which were aggravated by standing and walking, and had noticed red tender lumps on the legs. On examination there was pronounced tenderness of the calf muscles, but no other abnormalities. normal differential. Electrophoresis of serum proteins showed raised alpha-2 globulin; serum muscle enzymes showed raised lactic dehydrogenase; and rheumatoid factor, antinuclear factor, and L.E. cells were negative. Biopsy …