C4A and autoimmune polyendocrinopathy: Compared with the general population’s PE incidence of 3%–5%, SLE patients have a PE incidence ranging from 8% to 35%.7,23,27–29 Several studies have indicated a connection between LN, HTN, thrombocytopenia, hypocomplementemia, disease flare-ups, or the presence of aPLs and the development of PE.30–32 We identified HTN, a history of PE, associated APS, 24-hour proteinuria, and low serum C4 as independent risk factors for PE.