CSF IgA NMDAR antibodies are potential biomarkers for teratomas in anti-NMDAR encephalitis.

Abstract

OBJECTIVE:

To evaluate the presence of immunoglobulin A (IgA) subtype of anti-NMDA receptor (NMDAR) antibodies (IgA-NMDAR-Abs) in the CSF of patients with immunoglobulin G (IgG)-NMDAR-Ab encephalitis and to describe the potential association with a specific clinical pattern.

METHODS:

The retrospective analysis for the presence of IgA-NMDAR-Abs in 94 CSF samples from patients with anti-NMDAR encephalitis diagnosed between October 2007 and February 2014 was conducted at the French Reference Centre on Paraneoplastic Neurological Syndrome. This observational study compared 39 patients with both IgA- and IgG-NMDAR-Abs to 55 patients with only IgG-NMDAR-Abs.

RESULTS:

In the retrospective cohort, 41% of the patients with NMDAR-Ab encephalitis had both CSF IgG- and IgA-NMDAR-Abs. Approximately half of the IgA-NMDAR-Ab-positive patients (18/38, 49%) definitively possessed associated tumors, primarily ovarian teratomas (17/18, 94%), compared with only 5% (3/55) of the patients in the IgA-NMDAR-Ab-negative group (p < 0.001). In the adult female population at risk for ovarian teratoma, the detection of CSF IgA-NMDAR-Ab positivity showed 85% sensitivity, 70% specificity, a 57% positive predictive value, and a 90% negative predictive value for the diagnosis of ovarian teratoma. No other specific clinical features or clinical outcome were associated with CSF IgA-NMDAR-Ab positivity.

CONCLUSION:

These results suggest that in patients with IgG-NMDAR-Ab encephalitis, CSF IgA-NMDAR-Abs could be used as a biological marker for the presence of an ovarian teratoma.

• Authors: Virginie Desestret, Aude Chefdeville, Aurélien Viaccoz, Chloe Bost, François Ducray, Géraldine Picard, Veronique Rogemond, Marie-Oceane Chaffois, Charlotte Blanc, Claire Bardel, Isabelle Treilleux, Olivier Pascual, Jean-Christophe Antoine, Jean-Yves Delattre, Jerome Honnorat
• Journal: Neurology(R) neuroimmunology & neuroinflammation (Neurol Neuroimmunol Neuroinflamm) Vol. 2 Issue 6 Pg. e166 (Dec 2015) ISSN: 2332-7812 [Print] United States
• PMID: 26568967 (Publication Type: Journal Article)