503. Lack of coronary aneurysms during Kawasaki Disease (KD) correlates with higher levels of autoantibodies to both full form and spliced variant of immune regulator EDIL-3 (Del-1)

Abstract Background Kawasaki disease is a rare multisystem inflammatory condition that mainly affects children under the age of 5 years. Current theory pathogenesis an infectious stimulus triggers autoimmune reaction in genetically susceptible child. Recent studies demonstrated association with autoantibody response to EDIL3 (also known as DEL-1) KD. extracellular matrix protein which expressed both macrophages and vascular endothelium. EDIL3, has anti-inflammatory role by preventing leucocyte migration sites. Del-1 two expression variants genetic have been associated risk intracranial aneurysms. Due physiologic plausibility for during KD, we chose assess if autoantibodies against are seen larger cohort KD responses correlated aneurysm formation. Methods We assessed plasma samples from febrile children, including ELISA assay using recombinant ELISAs. Results Time course (pre-IVIG, post-IVIG convalescent) different patient cohorts showed there increased levels samples, consistent commonality antibodies. Contrary prior findings, comparison controls, were not higher Kd. Correlation signs cardiac inflammation lower levels. Conclusion Auto-antibodies common and, like other autoantibodies, IVIG formulation. Lower these may be susceptibility marker or sequestered Disclosures All Authors: No reported disclosures.