Skelly, Donal

This case series describes a distinctive inspiratory noise observed during sleep in patients with IgLON5-antibody disease.

Background N-methyl-D-aspartate receptor antibody encephalitis (NMDAR-Ab-E) can have an onset during, after or prior to a pregnancy. In animal models, transplacental NMDAR immunoglobulin G transfer can affect neurodevelopment. In contrast, clinical reports of mothers affected by NMDAR-Ab-E typically are reassuring. We systematically reviewed maternal, infant and childhood clinical data pertaining to NMDAR-Ab-E with an onset before, during or after pregnancy and compared this to our single autoimmune neurology centre experience. Methods After pre-registration on PROSPERO (CRD42023408447), we searched PubMed and Scopus for NMDAR-Ab-E case reports/series with an onset before, during or after pregnancy (last search 19/10/2023). We extracted maternal, neonatal and childhood outcomes using an idealised checklist to derive summary statistics. Results After quality control, we identified 66 pregnancies in 61 women from 48 reports or series. 72% of women recovered with minimal or no neurological deficits, comparable to non-pregnancy-associated NMDAR-Ab-E. Likewise, 80% of pregnancies resulted in live births with a single neonatal death reported. Data on neonatal outcome measures were frequently unreported, and childhood follow-up was provided in only 60%. Our centre’s experience is consistent: 3/4 mothers recovered with no functional deficits and 7/8 children without evidence of compromise at a median follow-up of 2 years. Conclusions Current evidence does not overall suggest unfavourable maternal, fetal or childhood outcomes after NMDAR-Ab-E. However, the available sample is small, predominantly single case reports with modest follow-up, lacks standardisation, and data are often incomplete. Future approaches should address these caveats: developing multi-centre collaboration towards an international registry.