Hashimoto encephalopathy (HE) is a rare condition often underdiagnosed. The clinical picture is heterogeneous with numerous neurological signs and is associated with the presence of high levels of anti-thyroperoxidase (TPO) and / or anti-thyroglobulin (TG) antibodies in the blood and cerebrospinal fluid (CSF). The determination of anti-TPO and anti-TG antibodies in CSF is performed in only few laboratories. The aim of our study was to adapt the EliATM fluoroenzymatic immuno assay (FEIA) to the detection of these autoantibodies in the CSF, and to compare the results with our previously published ELISA test (Blanchin S. 2007). For the FEIA technique, the detection threshold, and the quantification threshold have been determined for anti-TPO and anti-TG antibodies. FEIA results were concordant with ELISA at 75% and 100% for anti-TPO and anti-TG antibodies, respectively. Coefficients of variation (CV) of the intra-assay and inter-assay results were calculated as well as the uncertainties of measurement. The anti-TPO and anti-TG antibodies detection in CSF using FEIA technique correlate with the previously published ELISA and show good analytical performances. The availability of PhadiaTM 250 analyzer in a large number of laboratories will allow an easier biological detection. We hope that this test will respond to physician needs and help for HE diagnosis.
Keywords: Anti-thyroglobulin antibodies (anti-TG); Anti-thyroperoxydase antibodies (anti-TPO); Cerebrospinal fluid (CSF); Encephalopathy Associated with Auto-immune Thyroid disease (EAAT); Fluorescent-Enzyme Immuno Assay (FEIA); Hashimoto's Encephalopathy (HE); Steroid-Responsive Encephalopathy Associated with auto-immune Thyroiditis (SREAT).