Serum complement levels in rheumatoid arthritis. A longitudinal study of 43 cases with correlation of clinical and serological data including rheumatoid factor and thermolabile inhibitor of the F-II L.P. test.

Complement metabolism in rheumatoid arthritis. I. Longitudinal studies.

“…The spontaneous fluctuation of complement levels during the course of the disease is interesting and has been noted previously (Schubart, Ewald, Schroeder, Rothschild, Bhatavadekar, and Pullen, 1965). Thus rheumatoid disease, by these immunological parameters, is seen as a variable and even episodic disorder.…”

Serum immunoglobulin and beta 1C-beta 1A globulin concentrations in juvenile rheumatoid arthritis.

“…None of our patients had subnormal complement levels. Despite variable levels of complement in the serum of adult rheumatoid patients, low levels have been found consistently in adult rheumatoid synovial fluids, with one report of similar results in children, and more recently degradation products of complement (C3) have been demonstrated in synovial fluid (Schubart, Ewald, Schroeder, Rothschild, Bhatavadekar, and Pullen, 1965;Pekin and Zvaifler, 1962;Hedberg, Lundh, and Laurell, 1970). It is possible, therefore, that there could be an increased intraarticular consumption of complement in rheumatoid arthritis, despite the normal or elevated serum complement levels in this disease (Weinstein, Peters, Brown, and Bluestone, 1972).…”

Detection of immune complexes in acute rheumatic fever and their relationship to HLA-B5.

“…This situation has been observed in immune complexmediated disorders such as rheumatoid arthritis. In this disorder, circulating immune complexes have frequently been detected (27,37) even though complement has generally been normal or elevated (36,38,39). The presence of activated complement products (40) and the accelerated turnover of certain complement components (41)(42)(43) demonstrated that complement consumption occurs in patients with rheumatoid arthritis.…”