Axonal damage in chronic inflammatory demyelinating polyneuropathy (CIDP) is the main predictor of poor outcome. We hypothesized that serum neurofilament light chain (sNfL) reflects disease activity by detecting ongoing neuro‐axonal damage in CIDP. Three prospective cohorts of CIDP patients were studied: (a) patients starting induction treatment (IT cohort, N = 29) measured at baseline and 6 months after starting treatment; (b) patients on maintenance treatment (MT) starting intravenous immunoglobuline (IVIg) withdrawal (MT cohort, N = 24) measured at baseline and 6 months after IVIg withdrawal or at time of relapse; and (c) patients in long‐term remission without treatment (N = 27). A single molecule array assay was used to measure sNfL. Age‐matched healthy controls (N = 30) and age‐specific reference values were used for comparison. At baseline, sNfL was higher in patients starting IT compared to healthy controls. Ten out of 29 IT (34%) patients have sNfL levels above the 95th percentile of age‐specific cut‐off values. In the MT and remission cohort, elevated sNfL levels were infrequent and not different from healthy controls. sNfL levels were correlated with electrophysiological markers of axonal damage. At follow‐up assessment, patients with active disease (non‐responders and patients who relapsed after IVIg withdrawal) had higher sNfL levels compared with patients with stable disease (responders and patients who were successfully withdrawn from IVIg treatment). sNfL levels were increased in a third of CIDP patients starting IT and reflected axonal damage. sNfL levels might be usable as biomarker of disease activity in a subset of CIDP patients.

BackgroundChronic inflammatory demyelinating polyneuropathy (CIDP) can be treated with corticosteroids or intravenous immunoglobulins. Various corticosteroid regimens are currently used in CIDP, but it is unknown whether they are equally efficacious. In this retrospective study, we compared efficacy and safety of three corticosteroid regimens in CIDP patients.MethodsWe included treatment naïve patients that fulfilled the EFNS/PNS criteria for CIDP. Patients were treated with corticosteroids according to the local protocol of three CIDP expertise centres. Corticosteroid regimens consisted of daily oral prednisolone, pulsed oral dexamethasone, or pulsed intravenous methylprednisolone. Outcomes were number of responders to treatment, remission rate of treatment responders, overall probability of 5-year remission, and the occurrence of adverse events.ResultsA total of 125 patients were included. Sixty-seven (54%) patients received daily prednisone or prednisolone, 37 (30%) pulsed dexamethasone, and 21 (17%) pulsed intravenous methylprednisolone. Overall, 60% (95% CI 51–69%) responded to corticosteroids, with no significant difference between the three treatment regimens (p = 0.56). From the 75 responders, 61% (95% CI 50–73%) remained in remission, during a median follow-up of 55 months (range 1–197 months). The probability of responders reaching 5-year remission was 55% (95% Cl 44–70%), with no difference between the three groups. Adverse events leading to a change in treatment occurred in ten patients (8%). Two patients had a serious adverse event.ConclusionCorticosteroids lead to improvement in 60% of patients and to remission in 61% of treatment responders. There were no differences between treatment modalities in terms of efficacy and safety.

Objective To assess clinical outcome in treatment-naive patients with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). Methods We included adult treatment-naive patients participating in the prospective International CIDP Outcome Study (ICOS) that fulfilled the European Federation of Neurological Societies/Peripheral Nerve Society (EFNS/PNS) diagnostic criteria for CIDP. Patients were grouped based on initial treatment with (1) intravenous immunoglobulin (IVIg), (2) corticosteroid monotherapy or (3) IVIg and corticosteroids (combination treatment). Outcome measures included the inflammatory Rasch-built overall disability scale (I-RODS), grip strength, and Medical Research Council (MRC) sum score. Treatment response, treatment status, remissions (improved and untreated), treatment changes, and residual symptoms or deficits were assessed at 1 year. Results Forty patients were included of whom 18 (45%) initially received IVIg, 6 (15%) corticosteroids, and 16 (40%) combination treatment. Improvement on ≥ 1 of the outcome measures was seen in 31 (78%) patients. At 1 year, 19 (48%) patients were still treated and fourteen (36%) patients were in remission. Improvement was seen most frequently in patients started on IVIg (94%) and remission in those started on combination treatment (44%). Differences between groups did not reach statistical significance. Residual symptoms or deficits ranged from 25% for neuropathic pain to 96% for any sensory deficit. Conclusions Improvement was seen in most patients. One year after the start of treatment, more than half of the patients were untreated and around one-third in remission. Residual symptoms and deficits were common regardless of treatment.