Infections are a major cause of hospitalization and death in adults with lupus, but little is known about the risk of infections and how to reduce these risks in children with pediatric lupus (pSLE). While the CARRA Registry offers a rich source of medication and other outpatient data, there is less information on what happens during hospitalizations, especially during unexpected complications like serious infections. Our project will link a large national database with information on emergency department visits and inpatient hospitalizations with the CARRA Registry to determine rates of infection. We will use this information to evaluate and improve infection reporting in the CARRA Registry. Finally, we will use this linked CARRA-PHIS dataset to identify risk factors for infection, including the different risks posed by specific medications used for lupus.