Diagnostic specificity of autoantibodies. II. Clustering of autoantibodies--role in diagnosis and in comparison to E--and EAC-RFC peripheral blood profiles and immunoglobulin levels.

Clustering of ANA and SMA was evaluated in patients with various internal diseases as a pattern of autoantibody formation. SMA was found in ANA positive patients with chronic hepatitis, undefined collagenoses and autoallergic thyroid diseases significantly more frequently, than in patients without any autoallergic disorders. The incidence of SMA in ANA positive cases with SLE and RA did not exceed their predictable by chance incidence. It was not found that clustering of autoantibodies is correlated with the E and C lymphocyte receptor abnormality as compared to the control group. The lowest count of E-RFC was found in SLE cases which differed significantly in this respect from the control group and also from chronic vasculitis cases. The clustering of autoantibodies is not correlated with hyperimmunoglobulinemia.