Therapy-resistant autoimmune nodopathy with anti-neurofascin 155 antibodies: a case report

Abstract

This study reports the case of a previously healthy man in his late 20s who began experiencing symptoms 3 months before admission to our hospital, including arm and leg weakness and distal hypesthesia. Initially, the patient responded to corticosteroid therapy. However, as his symptoms progressed, he underwent plasmapheresis and received intravenous immunoglobulin therapy, neither of which led to any discernible improvement. With rapid symptom progression during subsequent hospital visits, further investigation led to the detection of neurofascin 155 antibodies. Based on existing evidence of its efficacy, rituximab treatment was initiated. To date, the patient has received three doses of rituximab, which has been partially ineffective. Thus, treatment is ongoing and includes a combination of rituximab and subcutaneous immunoglobulin.

Keywords: antibodies; autoimmune; neurofascin; nodopathy; polyneuropathy.

Figure 1

Graphical summarization of the treatment. The scale of doses for methylprednisolone (grey) and rituximab is shown on the left side of the graph. The scale of doses for prednisone (yellow), IVIg (orange), and ScIg (dark red) is shown on the right side of the graph. Plasma exchange (light blue) is shown for illustrative purposes as to when it was performed.

Figure 2

Graphical summarization of the used evaluation scales. The sum scores for the scales ONLS (grey) and INCAT (yellow) are shown on the left side of the graph. The sum scores for the scales I-RODS (light blue) and MRC (orange) are shown on the right side of the graph. For the MRC scale, the more sensitive muscle groups were picked to be evaluated and comprise the shown sum: upper arm abductors, elbow flexors, wrist extensors, hip flexors, knee extensors, and foot dorsal flexors (Kleyweg et al., n.d.). The figure represents changes in evaluation scores throughout the clinical case. By comparing with Figure 1, primary improvement was observed following corticosteroid therapy, and the following declines can be attributed to prednisone dose reduction, from 30 mg/day and lower. There seemed to be an improvement after rituximab treatment in the first 24 days (between days 79 and 103), but following that, there was a decline in the patient’s state as the prednisone dose was reduced. The improvement after starting rituximab should typically be seen after 2 months of treatment, yet there was no clear improvement. Substantial improvement became apparent after starting treatment with subcutaneous immunoglobulin, which is apparent in the evaluation scores and reduction in the prednisone dose following day 205.