Diagnostic value of CSF findings in antibody-associated limbic and anti-NMDAR-encephalitis.

Abstract

PURPOSE:

In people with suspected inflammatory CNS disease, cerebrospinal fluid (CSF) is commonly analyzed. Antibody-associated limbic encephalitis (ab-LE) and anti-NMDAR-encephalitis are recognized as two major syndromes of autoimmune epilepsies. Here, we investigated the diagnostic value of CSF findings in these two entities.

METHODS:

We reviewed patients from our tertiary epilepsy centre with ab-LE and anti-NMDAR-encephalitis in whom CSF examination including oligoclonal bands (OCB) was performed. Ab-LE patients were subdivided according to antibodies (voltage-gated potassium channels, VGKC; glutamic acid decarboxylase, GAD) or presence of onconeural antibodies/presence of tumour into three groups: VGKC-LE, GAD-LE or paraneoplastic LE (PLE). As controls, patients with CSF investigations in whom autoimmune origin was initially assumed but not confirmed later on were included. In addition, a review of published ab-LE and anti-NMDAR-encephalitis cases with reported CSF data was performed.

RESULTS:

55 ab-LE (23 VGKC-LE, 25 GAD-LE, 7 PLE) and 14 anti-NMDAR-encephalitis patients were identified at our centre. OCB were significantly more frequent in ab-LE and anti-NMDAR-encephalitis than in controls. Literature review identified 150 ab-LE and 95 NMDAR cases. Analysis of pooled data confirmed that presence of OCB was significantly more frequent in ab-LE and anti-NMDAR-encephalitis (especially in people with GAD-LE and anti-NMDAR encephalitis) as compared to controls. Sensitivity and specificity of OCB in the pooled ab-LE and anti-NMDAR-encephalitis patients was 34% and 96%, respectively. In patients with ab-LE and anti-NMDAR-encephalitis, the likelihood of OCB in CSF was 8.5-fold higher as compared to controls. Furthermore, in the pooled ab-LE and anti-NMDAR-encephalitis patients, cell counts in CSF were more frequently elevated (especially in those with anti-NMDAR encephalitis) than in controls, whereas protein content of CSF was not different between the groups.

CONCLUSION:

OCB, and to a lesser extent cell counts in CSF, appear to be helpful additional CSF markers in the diagnostic evaluation of people presenting with a constellation suggestive for GAD-LE, PLE and anti-NMDAR-encephalitis, prompting subsequent analysis of specific antibodies.

• Authors: Michael P Malter, Christian E Elger, Rainer Surges
• Journal: Seizure (Seizure) Vol. 22 Issue 2 Pg. 136-40 (Mar 2013) ISSN: 1532-2688 [Electronic] England
• PMID: 23318046 (Publication Type: Journal Article, Research Support, N.I.H., Extramural, Review)
• Copyright: Copyright © 2012 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.

Chemical References

• Autoantibodies
• Biomarkers
• Nerve Tissue Proteins
• Receptors, N-Methyl-D-Aspartate

Topics

• Anti-N-Methyl-D-Aspartate Receptor Encephalitis (cerebrospinal fluid, diagnosis, immunology)
• Autoantibodies (biosynthesis, cerebrospinal fluid)
• Biomarkers (cerebrospinal fluid)
• Humans
• Limbic Encephalitis (cerebrospinal fluid, diagnosis, immunology)
• Nerve Tissue Proteins (immunology)
• Receptors, N-Methyl-D-Aspartate (immunology)
• Retrospective Studies