Serum neurofilament light chain does not detect self‐reported treatment‐related fluctuations in chronic inflammatory demyelinating polyneuropathy

Abstract

IntroductionSerum neurofilament light chain (sNfL) is a marker for axonal degeneration. Patients with CIDP often report a fluctuation of symptoms throughout one treatment cycle with immunoglobulin (IVIG). The aim of this study was to determine whether sNfL is suitable to quantify patient reported symptom fluctuations.Methods29 patients with the diagnosis of CIDP or a CIDP‐variant under treatment with IVIG were recruited in this study and underwent examination before IVIG infusion, in the middle of the treatment interval and before their next IVIG infusion. Patients were surveyed regarding symptom fluctuations at the last visit and divided into two groups: with and without fluctuations of symptoms. At the first visit socio‐demographic and disease specific data were collected. Clinical scores were assessed at every examination. sNfL values were compared between both groups at the different time points after conversion into Z‐Scores – adjusted for age and BMI.ResultsPatients with CIDP show elevated sNfL Z‐Scores (median at baseline: 2.14, IQR: 1.0). There was no significant change of sNfL Z‐Scores or questionnaire scores within the treatment cycle in either group. There was no significant difference in sNfL levels between the patients with and without symptom fluctuations.ConclusionCIDP patients show elevated sNfL levels. However, sNfL is not suitable to reflect patient‐reported fluctuations of symptoms. This indicates that symptom fluctuations during treatment with IVIGs in patients with CIDP are not caused by a neuroaxonal injury. Furthermore, repeated sNfL measurements within one treatment cycle with IVIGs seem to have no benefit for symptom‐monitoring.

Serum Glycobiomarkers Defining Therapeutic Response to Intravenous Immunoglobulin in Chronic Inflammatory Demyelinating Polyneuropathy

“…An increase in serum NfL was confirmed to be associated with disease progression 1 year after serum sampling in patients with CIDP but has not been shown to reflect short-term treatment responses after IVIg administration. 38–40 In our study, we also confirmed that serum NfL was not associated with treatment responsiveness to initial IVIg. Instead, the levels of serum glycans were associated with short-term initial response to IVIg treatment.…”