PMC9176167_01
Patient's MRI and EEG. Patient N 1 brain MRI in axial FLAIR (fluid attenuated inversion recovering) sequence (A) and coronal T1 weighted sequence (B) showed periventricular confluent leukopathy (thin white arrows - A), cortical and subcortical atrophy predominant on the right hemisphere and a significant dilatation of lateral and third ventricles (large white arrows - B). (C) Patient N 2 had a hyposignal of the two pallidal tips in axial T2* sequence (white arrows). (D) Hippocampal atrophy, predominant on the left side, on patient's N 3 axial FLAIR MRI (white arrows). All MRI were performed on 3 Tesla devices (Magnetom Skyra, Siemens Healthcare, Erlangen, Germany and Achieva 3.0 T, Philips, Amsterdam, Netherlands). (E) Patient N 1 also had recurrent bilateral anterior delta waves on a 6.5 Hz basic rhythm (black arrows). (F) Patient N 2 had a non-pharmacological, bilateral and anterior fast rhythm at 14 Hz (black arrows). EEGs were performed and read on Deltamed devices and software (Natus Neurology, Pleasanton, USA).
fneur-13-847798-g0001.jpg
PMC9176167_03_fneur-13-847798-g0001.jpg
F1
Brain MRI showed a mild leukopathy, usual at that age, hippocampal atrophy, and a right-sided occipital meningioma (Figure 1D).
Indirect immunofluorescence on monkey cerebellum slices (ref. 0665042225.10, NOVA Lite, Inova, Falls Church, USA) showing atypical and intense staining of the white matter for patient N 1 [(A), x 20, IgM kappa monoclonal gammopathy], identical when a secondary antibody anti-IgG, anti-IgM or anti-kappa was used but negative with an anti-lambda antibody. The same staining was found for patient N 2 with anti-IgG [(B), x 20], anti-IgM and anti-lambda [(C), x 40, IgM lambda monoclonal gammopathy] but negative with anti-kappa. Patient N 3 (IgG kappa monoclonal gammopathy) had a positive staining only with anti-IgG and anti-kappa secondary antibody [(D), x 20]. A fine speckled staining was also present in cortex [(E), x 20 and (F), x 40] for all patients. Immunostaining positivity was only present within sera but negative within CSF. Anti-MAG antibodies presence was tested on monkey nerve slice (ref. 066504210.10, NOVA Lite) and confirmed by ELISA (ref. EK-MAG, Bhlmann, Bremen, Germany).
fneur-13-847798-g0002.jpg
PMC9176167_03_fneur-13-847798-g0002.jpg
F2
Biological work-up showed an IgG kappa monoclonal gammopathy at 14.28 g/L and a bright fluorescence of the white matter (with anti-IgG and anti-kappa only) on monkey cerebellum slices when anti-neuronal antibodies were searched (Figure 2D).
PMC9176167_02
Patient's MRI and EEG. Patient N 1 brain MRI in axial FLAIR (fluid attenuated inversion recovering) sequence (A) and coronal T1 weighted sequence (B) showed periventricular confluent leukopathy (thin white arrows - A), cortical and subcortical atrophy predominant on the right hemisphere and a significant dilatation of lateral and third ventricles (large white arrows - B). (C) Patient N 2 had a hyposignal of the two pallidal tips in axial T2* sequence (white arrows). (D) Hippocampal atrophy, predominant on the left side, on patient's N 3 axial FLAIR MRI (white arrows). All MRI were performed on 3 Tesla devices (Magnetom Skyra, Siemens Healthcare, Erlangen, Germany and Achieva 3.0 T, Philips, Amsterdam, Netherlands). (E) Patient N 1 also had recurrent bilateral anterior delta waves on a 6.5 Hz basic rhythm (black arrows). (F) Patient N 2 had a non-pharmacological, bilateral and anterior fast rhythm at 14 Hz (black arrows). EEGs were performed and read on Deltamed devices and software (Natus Neurology, Pleasanton, USA).
fneur-13-847798-g0001.jpg
PMC9176167_03_fneur-13-847798-g0001.jpg
F1
Brain MRI showed a mild leukopathy, usual at that age, hippocampal atrophy, and a right-sided occipital meningioma (Figure 1D).
Indirect immunofluorescence on monkey cerebellum slices (ref. 0665042225.10, NOVA Lite, Inova, Falls Church, USA) showing atypical and intense staining of the white matter for patient N 1 [(A), x 20, IgM kappa monoclonal gammopathy], identical when a secondary antibody anti-IgG, anti-IgM or anti-kappa was used but negative with an anti-lambda antibody. The same staining was found for patient N 2 with anti-IgG [(B), x 20], anti-IgM and anti-lambda [(C), x 40, IgM lambda monoclonal gammopathy] but negative with anti-kappa. Patient N 3 (IgG kappa monoclonal gammopathy) had a positive staining only with anti-IgG and anti-kappa secondary antibody [(D), x 20]. A fine speckled staining was also present in cortex [(E), x 20 and (F), x 40] for all patients. Immunostaining positivity was only present within sera but negative within CSF. Anti-MAG antibodies presence was tested on monkey nerve slice (ref. 066504210.10, NOVA Lite) and confirmed by ELISA (ref. EK-MAG, Bhlmann, Bremen, Germany).
fneur-13-847798-g0002.jpg
PMC9176167_03_fneur-13-847798-g0002.jpg
F2
Biological work-up showed an IgG kappa monoclonal gammopathy at 14.28 g/L and a bright fluorescence of the white matter (with anti-IgG and anti-kappa only) on monkey cerebellum slices when anti-neuronal antibodies were searched (Figure 2D).
PMC9176167_03
Patient's MRI and EEG. Patient N 1 brain MRI in axial FLAIR (fluid attenuated inversion recovering) sequence (A) and coronal T1 weighted sequence (B) showed periventricular confluent leukopathy (thin white arrows - A), cortical and subcortical atrophy predominant on the right hemisphere and a significant dilatation of lateral and third ventricles (large white arrows - B). (C) Patient N 2 had a hyposignal of the two pallidal tips in axial T2* sequence (white arrows). (D) Hippocampal atrophy, predominant on the left side, on patient's N 3 axial FLAIR MRI (white arrows). All MRI were performed on 3 Tesla devices (Magnetom Skyra, Siemens Healthcare, Erlangen, Germany and Achieva 3.0 T, Philips, Amsterdam, Netherlands). (E) Patient N 1 also had recurrent bilateral anterior delta waves on a 6.5 Hz basic rhythm (black arrows). (F) Patient N 2 had a non-pharmacological, bilateral and anterior fast rhythm at 14 Hz (black arrows). EEGs were performed and read on Deltamed devices and software (Natus Neurology, Pleasanton, USA).
fneur-13-847798-g0001.jpg
PMC9176167_03_fneur-13-847798-g0001.jpg
F1
Brain MRI showed a mild leukopathy, usual at that age, hippocampal atrophy, and a right-sided occipital meningioma (Figure 1D).
Indirect immunofluorescence on monkey cerebellum slices (ref. 0665042225.10, NOVA Lite, Inova, Falls Church, USA) showing atypical and intense staining of the white matter for patient N 1 [(A), x 20, IgM kappa monoclonal gammopathy], identical when a secondary antibody anti-IgG, anti-IgM or anti-kappa was used but negative with an anti-lambda antibody. The same staining was found for patient N 2 with anti-IgG [(B), x 20], anti-IgM and anti-lambda [(C), x 40, IgM lambda monoclonal gammopathy] but negative with anti-kappa. Patient N 3 (IgG kappa monoclonal gammopathy) had a positive staining only with anti-IgG and anti-kappa secondary antibody [(D), x 20]. A fine speckled staining was also present in cortex [(E), x 20 and (F), x 40] for all patients. Immunostaining positivity was only present within sera but negative within CSF. Anti-MAG antibodies presence was tested on monkey nerve slice (ref. 066504210.10, NOVA Lite) and confirmed by ELISA (ref. EK-MAG, Bhlmann, Bremen, Germany).
fneur-13-847798-g0002.jpg
PMC9176167_03_fneur-13-847798-g0002.jpg
F2
Biological work-up showed an IgG kappa monoclonal gammopathy at 14.28 g/L and a bright fluorescence of the white matter (with anti-IgG and anti-kappa only) on monkey cerebellum slices when anti-neuronal antibodies were searched (Figure 2D).