Dataset Information

Comparison of diagnostic accuracy of microscopy and flow cytometry in evaluating N-methyl-D-aspartate receptor antibodies in serum using a live cell-based assay.

ABSTRACT: N-methyl-D-aspartate receptor (NMDAR) encephalitis is an autoimmune neurological disease, diagnosed by a specific autoantibody against NMDAR. Antibody testing using commercially available cell-based assays (CBA) or immunohistochemistry on rat brain tissue has proven high specificity and sensitivity. Here we compare an immunofluorescence live CBA to a flow cytometry (FACS) based assay to detect NMDAR antibodies by their binding to the surface of HEK293A cells functionally expressing NMDAR. Both assays were first established using a discovery group of 76 individuals and then validated in a group of 32 patients in a blinded manner. In the CBA, 23 of 23 patients with NMDAR encephalitis were positive for NMDAR antibodies and 0 of 85 controls (32 healthy controls and 53 patients with other neurological diseases), resulting in a sensitivity and specificity of 100% (95% confidence intervals (CI) 85.1-100.0 and 95.7-100.0, respectively). The FACS based assay detected NMDAR antibodies in 20 of 23 patients and in 0 of 85 controls. Therefore, with an equally high specificity (95% CI 95.7-100.0) the sensitivity of the FACS based assay was 87% (95% CI 66.4-97.2). Comparing antibody titers from CBA with delta median fluorescence intensities from FACS showed a high concordance (kappa = 0.943, p<0.0001) and correlation (r = 0.697, p<0.0001). In conclusion, evaluation of the FACS based assay revealed a lower sensitivity and high inter-assay variation, making the CBA a more reliable detection method.

SUBMITTER: Ramberger M

PROVIDER: S-EPMC4376531 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

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Comparison of diagnostic accuracy of microscopy and flow cytometry in evaluating N-methyl-D-aspartate receptor antibodies in serum using a live cell-based assay.

Ramberger Melanie M Peschl Patrick P Schanda Kathrin K Irschick Regina R Höftberger Romana R Deisenhammer Florian F Rostásy Kevin K Berger Thomas T Dalmau Josep J Reindl Markus M

PloS one 20150327 3

N-methyl-D-aspartate receptor (NMDAR) encephalitis is an autoimmune neurological disease, diagnosed by a specific autoantibody against NMDAR. Antibody testing using commercially available cell-based assays (CBA) or immunohistochemistry on rat brain tissue has proven high specificity and sensitivity. Here we compare an immunofluorescence live CBA to a flow cytometry (FACS) based assay to detect NMDAR antibodies by their binding to the surface of HEK293A cells functionally expressing NMDAR. Both a ...[more]

PMID: 25815887

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Dataset Information

Comparison of diagnostic accuracy of microscopy and flow cytometry in evaluating N-methyl-D-aspartate receptor antibodies in serum using a live cell-based assay.

Publications

Comparison of diagnostic accuracy of microscopy and flow cytometry in evaluating N-methyl-D-aspartate receptor antibodies in serum using a live cell-based assay.

Similar Datasets

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