Observation of therapeutic plasma exchange in the treatment of pediatric severe critical anti-N-methyl-D-aspartate receptor encephalitis

Abstract

Objective To investigate the features and incidence of severe anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis in pediatric intensive care unit (PICU) treated with therapeutic plasma exchange(TPE). Methods A retrospective study was conducted of children with severe anti NMDAR encephalitis admitted to PICU of Shanghai Children′s Hospital from July 2015 to June 2018.Demographic data, therapeutic regimens, clinical and laboratory data were analyzed.The one dose of replacement plasma was 50-70 ml/kg.The laboratory biomarkers, anti-NMDAR in serum and cerebrospinal fluid(CSF) were measured before and after TPE treatment. Results Thirteen cases with anti-NMDAR encephalitis were analyzed.The main clinical features were seizures, unconsciousness, motor dysfunctions organ dysfunction included respiratory failure in 3 (23.1%) patients and shock in 4 (30.8%) cases.The average levels of PICU stays were[11.0(5.5, 19.0)] days.The conventional therapy included methylprednisolone, intravenous immunoglobulin (IVIG), antiepileptic, and immune-suppressants.Seven patients received conventional treatment, and 6 (46.2%) cases combined TPE after unsatisfactory effect on 3 to 7 days conventional treatment.TPE dosage was 50-70 ml/kg body weight per times for 3-5 dosages.The Glasgow coma score(GCS) and pediatric risk of mortality Ⅲ(PRISM Ⅲ) of children after TPE treatment were signifcantly improved compared with those before TPE treatment[GCS: 7.5(6.0, 9.3) vs. 12.5(11.5, 13.5), PRISM Ⅲ: 15.5(9.5, 17.5) vs. 11.0(4.5, 12.3), all P<0.05]. The levels of anti-NMDAR antibody in both serum and CSF decreased significantly after TPE(all P<0.05). Three cases (50.0%) had anaphylaxis during TPE. Conclusion TPE could decease the levels of anti-NMDAR antibody in CSF and serum, improve psychiatric and neurologic symptoms.TPE may be a potential therapy in pediatric severe NMDAR encephalitis. Key words: Therapeutic plasma exchange; Anti-N-methyl-D-aspartate receptor encephalitis; Critically ill; Pediatric intensive care unit