Prevalence and pattern of antiphospholipid antibody syndrome in a hospital based longitudinal study of 193 patients of systemic lupus erythematosus.

BACKGROUND Antiphospholipid antibody syndrome (APS) is a systemic autoimmune disease characterised by thrombophilic state and obstetrical complications. Prevalence of APS varies in different parts of the world. So this study was conducted to find out the prevalence and pattern of APS in systemic lupus erythematosus (SLE) in this region. MATERIAL AND METHODS In this hospital based longitudinal study from 2004 to 2011, we studied 193 patients of systemic lupus erythematosus (SLE) for prevalence of APS and its different characteristics. The diagnosis of SLE was made according to American College of Rheumatology (ACR) criteria and diagnosis of APS was made according to Sapporo criteria. RESULTS Prevalence of APS in SLE was 25.38%. Mean age at study entry was 25.5 +/- 6.9 years and majority of APS patients were in the age group 21-30 yrs (44.89%). The most common clinical manifestation in both SLE with APS and SLE without APS was musuloskeletal involvement (79.59% and 84.72% respectively). Among 49 patients of SLE having APS, multisystem involvement was present in 16 patients and life threatening complications were present in 12 patients. Late foetal loss was the most common obstetrical manifestation of APS (26.53%) and deep vein thrombosis was most common thrombotic manifestation (16.32%). Anticardiolipin antibodies(IgG aCL) were the most common antibody (85.71%) detected. Lupus anticoagulant was present in 71.42% cases of SLE having APS. ANA and anti-dsDNA antibodies were present in 97.95% and 77.55% cases of SLE having APS. CONCLUSION APS is a major cause of morbidity and mortality in patients of SLE. The incidence of secondary APS in SLE varies in different geographical regions and it was 25.38% in our study. Pregnancy morbidity and deep vein thrombosis were the most common complications of APS. IgG aCL was the most common antibody in APS patients. Screening for the presence of aPL antibodies in SLE patients and timely initiation of prophylactic treatment can prevent many of the complications.