Use of intravenous immunoglobulin compared with standard therapy is associated with improved clinical outcomes in children with acute encephalitis syndrome complicated by myocarditis.

Although an autoimmune mechanism has been postulated for acute encephalitis syndrome (AES) complicated by myocarditis, immunomodulatory treatment strategies are still under investigation. To study the role of intravenous immunoglobulin (IVIG) in AES complicated by myocarditis in children age 2-12 years. This nonrandomized study was conducted in a tertiary care teaching hospital from July 2008 to January 2010. A total of 83 consecutive children with AES complicated by myocarditis were enrolled. Diagnosis of myocarditis was based on clinical, electrocardiogram, and echocardiogram findings. Patients were allocated to the two groups based on the days of the week: Those presenting on Monday and Friday were allocated to IVIG treatment (group I), and those presenting on the other days of the week to standard care (group II). Group I (n = 26) patients received IVIG at a dose of 400 mg/kg/day for 5 days in addition to standard care. All baseline and outcome data were recorded prospectively in a prestructured performa. The primary outcomes were mortality and improvement of left-ventricular dysfunction. A total of 83 children were studied: 26 in group I and 57 in group II. The mean (SD) age of the enrolled children was 4.6 years (3.1). The baseline characteristics were comparable between the two groups. A viral etiology could be established in 14 children, with the 2 most common agents isolated being Coxackie virus and enterovirus. Mortality was lower in the IVIG group [n = 1 (3.8 %)] patients compared with the standard care group [n = 13 (22.8 %)] with a relative risk of 0.17 (95 % CI = 0.02, 1.22). The difference in mortality reached borderline significance (p = 0.05). At discharge, mean (SD) ejection fraction improved from 32.8 % (6.31 %) to 49.5 % (9.04 %) in group I patients, which was significantly greater than that of group II (p = 0.001). Use of IVIG seemed to have a beneficial effect in terms of improved clinical outcomes in children with AES complicated by myocarditis. Our findings need further validation before IVIG can be incorporated into the treatment protocol of these children.