Myositis-specific and myositis-associated autoantibody profiles and their clinical associations in a large series of patients with polymyositis and dermatomyositis

OBJECTIVE: To analyze the prevalence of myositis-specific and myositis-associated autoantibodies and their clinical correlations in a large series of patients with dermatomyositis/polymyositis. METHOD: This cross-sectional study enrolled 127 dermatomyositis cases and 95 polymyositis cases. The disease-related autoantibody profiles were determined using a commercially available blood testing kit. RESULTS: The prevalence of myositis-specific autoantibodies in all 222 patients was 34.4%, whereas myositis-associated autoantibodies were found in 41.4% of the patients. The most frequently found autoantibody was anti-Ro-52 (36.9%), followed by anti-Jo-1 (18.9%), anti-Mi-2 (8.1%), anti-Ku (4.1%), anti-SRP (3.2%), anti-PL-7 (3.2%), anti-PL-12 (2.7%), anti-PM/Scl75 (2.7%), and anti-PM/Scl100 (2.7%). The distributions of these autoantibodies were comparable between polymyositis and dermatomyositis, except for a higher prevalence of anti-Jo-1 in polymyositis. Anti-Mi-2 was more prevalent in dermatomyositis. Notably, in the multivariate analysis, anti-Mi-2 and anti-Ro-52 were associated with photosensitivity and pulmonary disorders, respectively, in dermatomyositis. Anti-Jo-1 was significantly correlated with pulmonary disorders in polymyositis. Moreover, anti-Ro-52 was associated with anti-Jo-1 in both diseases. No significant correlation was observed between the remaining autoantibodies and the clinical and/or laboratory findings. CONCLUSIONS: Our data are consistent with those from other published studies involving other populations, although certain findings warrant consideration. Anti-Ro-52 and anti-Jo-1 were strongly associated with one another. Anti-Ro-52 was correlated with pulmonary disorders in dermatomyositis, whereas anti-Jo-1 was correlated with pulmonary alterations in polymyositis. .

clinical significance of anti-Ro antibodies in patients with systemic lupus erythematosis

Systemic lupus erythematosus [SLE] is characterized by serum autoantibodies against protein components of small cytoplasmic ribo-nucleoproteins [scRNPs]. The origin and regulation of these anti-Ro/SS-A and anti-La/SS-B antibodies are not well understood. We attempted to define the association between the presence and absence of anti-Ro [SS-A] antibodies [Abs], and the criteria of SLE classification and non criteria manifestation of SLE, for better understanding of the disease course and prognosis. Ninety three SLE patients were included in the study. Retrospective analysis of their medical records was performed. 25% of SLE patients showed anti-Ro positive AB of which 91.3% were females. Anti Ro was significantly associated with lupus nephritis. While it showed a border line association with discoid rash and vasculitis. The presence of anti Ro antibodies with anti La antibodies increased the tendency of subcutaneous lupus to occur. Another interesting finding was the absence of antiphospholipid [APS] syndrome presentation [n=zero] in patients with anti Ro antibodies alone or in association with anti La positive antibodies versus seven patients detected with that syndrome in anti Ro and anti La negative group of patients [p=0.04]. Anti Ro is significantly associated with lupus nephritis. This may assist to predict renal involvement and to improve patient outcomes while simultaneously reducing disease costs. A paradox in disease severity may be suggested by a possible protective role against APL syndrome in these patients. The latter finding certainly warrants further investigations by studying larger population of patients

Antibodies to Ro/SS-A and La/SS-B in systemic lupus erythematosus and other autoimmune disorders.

AIM: 1. To study the presence of anti-Ro/SS-A, anti-La/SS-B, anti-Sm and anti-nRNP in diagnosed antinuclear factor (ANF) positive systemic lupus erythematosus (SLE) cases and their association with various organ involvement. 2. To study autoantibodies in other autoimmune disorders. MATERIAL AND METHODS: A total of 4050 suspected cases of autoimmune disorders referred for serological work up were evaluated for ANF by indirect immunofluorescence technique, anti-dsDNA by PHA, autoantibodies to Ro-SS-A and La/SS-B by ELISA and rheumatoid factor was tested by latex agglutination using commercial kits. RESULTS: Out of 4050 patients 19.5% were ANF positive and 5% were anti-dsDNA positive. Out of these 50 diagnosed ANF positive cases of SLE, an incidence of anti-dsDNA 54%, anti-Sm 25.9%, anti-nRNP 29.6%, anti-Ro/SS-A 10% and anti-La/SS-B was 22% was observed. In rheumatoid arthritis, 17.4% positivity of anti-Ro/SS-A and 39.1% positivity for anti-La/SS-B was observed. In SLE with renal involvement, joint complaints and skin or malar rash were seen in 66%, 56% and 46%, respectively. CONCLUSION: Determining anti-Ro/SS-A and anti-La/SS-B antibody could be important in evaluating patients with suspected connective tissue disorders, who usually show diverse clinical presentations like skin, kidney and joint manifestations. The most prominent feature in anti-Ro/SS-A and anti-La/SS-B positive patients was skin involvement and sicca complex in 60% of SLE patients.