THU0337 Nonbacterial thrombotic endocarditis (NBTE) in sle: prevalence, clinical characteristics and serological profile

Abstract

BackgroundSLE is characterised by excessive production of various autoantibodies and correlation of these antibodies with organ involvement may help to evaluate disease severity and long term prognosis. NBTE is a rare cardiac manifestation of SLE with prevalence rate varying from 6%–11%. Many, but no all, studies have shown association of NBTE with anti phospholipid antibodies, but, except this association, data regarding clinical, laboratory and serological characteristics of NBTE is sketchy. We designed this study to evauate profile of patients having NBTE in SLE.Objectives1. To study the prevalenence of NBTE in SLE patients.2. To study association of NBTE with clinical and laboratory characteristics and serological profile.MethodsAll consecutive SLE inpatients and outpatients attending the department of Rheumatology from September 2015 to December 2017 were enrolled. Patients subjected to 2D Echo were included and their demographic, clinical, laboratory and serological profile were recorded. Serological profile was studied with Blue diver kit which is an immunodot blot assay measuring autoantibodies against 25 ENA. Anti cardiolipin and anti beta 2 glycoprotein antibody were tested by ELISA. Study was approved by an independent ethics committee [ECR/282].ResultsTotal number of patients enrolled in study were 355 out of which 213 had undergone 2DEcho. NBTE was found in 33 (15.49%) patients. Among all autoantibodies studied, we found that the presence of anti-Nucleosome antibody, LAC, ACL and B2GP1 were significantly associated with NBTE (p<0.05). Myocarditis, valvular lesions and Pulmonary Hypertension were more common in NBTE group (p value: 0.012,<0.0001 and 0.013 respectively).We also noticed that there is a statistically significant association between presence of NBTE with APLA syndrome and Thrombotic events (p value<0.0001 and 0.005 respectively).Tab.1 Significant Serological association of SLE patients with NBTE.AntibodiesSLE With NBTE-33 (15.49%)SLE without NBTE-180P value Anti-nucleosome27 (81.8)32 (17.7)<0.0001LAC16/30 (53.3)31/149 (20.8)0.0002ACL (Ig M and IgG)9/303013/128 (10.1)0.004B2GP-1(Ig M and IgG)6/22209/103 (8.73)0.033APLA profile was available in 30 patients of NBTE and 147 patients not having NBTE. Out of this, positivity for APLA antibodies were seen in 17 (56.6%) and 36 (24.4%) patients respectively [p:0.005]. 82.3% patients with Anti phospholipid antibodies had APLA syndrome in NBTE group while in NBTE group 48.5% patients having Anti phospholipid antibodies had APLA syndrome. Thus, presence of NBTE increased the possibility of developing APLA syndrome in patients having positive serology for anti phospholipid antibodiesTab.2 Significant Clinical and laboratory characteristic of SLE patients with NBTE.Organ involvementSLE with NBTE-33SLE without NBTE-180p- value Myocarditis11270.012Valvulopathy104<0.0001PAH9210.013Thrombotic events8160.005APLA syndrome1417<0.0001ConclusionsPresence of Anti nucleosome antibody, LAC, Anti cardiolipin and anti beta 2 glycoprotein antibodies may predict presen...