THE "PARARHEUMATIC" ARTHROPATHIES

Abstract

Rheumatic fever, rheumatoid arthritis, lupus erythematosus disseminatus, polyarteritis nodosa, diffuse scleroderma and dermatomyositis are currently recognized as systemic alterations of the connective tissue. While the first 2 of these diseases are usually easily recognized, the 4 latter ones may present protean manifestations, bizarre clinical features, and difficult problems in differential diagnosis. To emphasize this clinical differentiation, the terms "rheumatic" and "pararheumatic" have been applied to the first 2 and the latter 4, respectively. As a corollary, the arthropathy noted in these 2 groups of diseases is designated as "rheumatic" and "pararheumatic," respectively. The incidence of musculoarticular manifestations in the "pararheumatic" diseases is high and the presenting complaints are often of this nature. 3 types of muscular and articular involvement are seen in the "pararheumatic" diseases: myalgias and arthralgias, acute or subacute migratory polyarthritis, and chronic, progressive, deforming polyarthritis. The 1st type resembles fibrositis; the 2d may mimic rheumatic fever, and the 3d may simulate rheumatoid arthritis. During the years 1938 to 1947, 36 cases of "pararheumatic" arthropathy were studied. All 13 cases of lupus erythematosus disseminatus presented musculoarticular symptoms. In 5 cases, articular involvement occurred before the appearance of the cutaneous eruption. Muscular and joint manifestations were noted in 7 of 8 cases of polyarteritis nodosa. In 3 of these the initial complaint was of this nature. The case of dermatomyositis had fibrositic symptoms. In the patient with diffuse scleroderma, pain and swelling of the joints preceded the dermatologic manifestations. "Pararheumatic" arthropathy should be suspected in patients exhibiting the following: fibrositis associated with fever, an acute or subacute polyarthritis of long duration with a downhill course, in fulminating, deforming polyarthritis, in "atypical" rheumatoid arthritis, and in arthritis with bizarre cutaneous lesions.