Relapsing Guillain Barré Syndrome and nephrotic syndrome secondary to focal segmental glomerulosclerosis

CIDP-like autoimmune nodopathy complicated with focal segmental glomerulosclerosis: a case study and literature review

BACKGROUND

This study aimed to investigate the role of neurofascin186 (NF186) in the pathogenesis of the concurrent focal segmental glomerulosclerosis (FSGS) in CIDP-like autoimmune nodopathy patients.

METHODS

We presented a case of CIDP-like autoimmune nodopathy complicated with FSGS. We measured NF186 antibodies by cell-binding assay (CBA) method. We performed immunofluorescence analysis in the renal cryosection samples from a patient with minimal nephropathy with rabbit anti-NF186 antibody or NF186 antibody positive human serum. Then we performed western blotting of recombinant NF186 protein and component of NF186 including Ig and FNIII domains incubating with human serum and corresponding rabbit polyclonal antibody. Cases of CIDP complicated with FSGS were searched form PubMed and reviewed.

RESULTS

We reported a 66-year-old Chinese woman with CIDP-like autoimmune nodopathy and concurrent FSGS. Her NF186 antibody was positive. The fluorescent signal for NF186 was detected in the renal tissue sections of the patient with minimal nephropathy. The staining for NF186 matched the podocyte spatially. In western blotting analysis, patients had antibodies in their serum recognizing the NF186 protein and their antibodies recognized the Ig domain of NF186. 3 cases of CIDP-like autoimmune nodopathy with positive NF186 antibody and FSGS have been reported. All these patients were responsive to corticosteroids rather than the intravenous immunoglobulin, in terms of both the neuropathy and renal disease.

CONCLUSIONS

NF186 was probably a targeted antigen in the pathogenesis of concurrent FSGS in CIDP-like autoimmune nodopathy with positive NF186 antibody. CIDP-like autoimmune nodopathy with positive NF186 antibody and FSGS is a rare entity, which may be responsive to corticosteroids combined with immunosuppressant.

Anti-Neurofascin-Associated Nephrotic-Range Proteinuria in Chronic Inflammatory Demyelinating Polyneuropathy

There are few case reports of concomitant chronic inflammatory demyelinating polyneuropathy (CIDP) and focal segmental glomerulosclerosis. A rare autoantibody to a neuronal and podocyte structural component, neurofascin, may be contributory. A Black man in his 40s presented with worsening polyneuropathy requiring mechanical ventilation and initially acute inflammatory demyelinating polyneuropathy was diagnosed. After a poor response to intravenous immunoglobulin, plasmapheresis was initiated. The patient also had concomitant new-onset nephrotic-range proteinuria. A limited kidney biopsy was interpreted as minimal change disease and was treated with prednisone. After some improvement, the patient was extubated; however, he later re-presented with worsening symptoms requiring mechanical ventilation and was re-treated with plasmapheresis. Due to the protracted course and poor response to intravenous immunoglobulin, acute-onset CIDP was diagnosed and a neuromuscular antibody workup returned positive for neurofascin, supporting the diagnosis of seropositive acute-onset CIDP. A repeat kidney biopsy demonstrated focal segmental glomerulosclerosis and acute tubular damage. The patient was treated with steroids and tacrolimus and later transitioned to rituximab. Neurofascin enzyme-linked immunosorbent assay then tested negative with concomitant resolution of both neuropathy and proteinuria. Further studies will help validate these findings and the treatment strategy.

Acute-onset chronic inflammatory demyelinating polyneuropathy with focal segmental glomerulosclerosis

Inflammatory neuropathies have been reported to occur in association with nephrotic syndrome. Their underlying immuno-pathogenic mechanisms remain unknown. A 50-year-old woman concurrently presented with acute-onset chronic inflammatory demyelinating polyneuropathy and nephrotic syndrome secondary to focal segmental glomerulosclerosis. Both neuropathy and proteinuria improved after plasma exchange and steroids. Literature review of cases of concurrent inflammatory neuropathies and nephrotic syndrome revealed similar neuro-renal presentations. This neuro-renal condition may be mediated by autoantibodies targeting myelin and podocytes.

Nephrotic syndrome

Nephrotic syndrome refers to excessive proteinuria, with associated hypoalbuminemia, edema, and hyperlipidemia. A diverse spectrum of disorders has been associated with nephrotic syndrome and related neurologic complications, although the relative infrequency of these cases limits conclusive associations. Neurologic manifestations of nephrotic syndrome may result from hypoproteinemia, hypercoagulability, hyperlipidemia, hypertension, amyloid deposition, hormonal changes, or electrolyte disorders. Neurologic diagnosis hinges on prompt recognition of this syndrome and rational therapeutic strategies are aimed at the underlying systemic disorder.

Steroid-responsive polyradiculopathy in association with focal segmental glomerulosclerosis

An 80-year-old woman presented with simultaneous increasing muscle weakness and nephrotic syndrome. A renal biopsy confirmed focal segmental glomerulosclerosis (FSGS). Her neurological diagnosis best fitted with a Guillain-Barre-like syndrome. There have been several cases of FSGS in combination with both conventional and atypical Guillain-Barre syndrome (GBS). Our patient was treated with high-dose steroids and resolution of both nephrotic syndrome and neurological symptoms occurred over 6 months. This article reviews all previously published presentations of this nature and discusses putative mechanisms for the development of concurrent FSGS and GBS.

A case of acute polyneuropathy with nephrotic syndrome showing transient proximal sensory conduction defects

Acute sensorimotor polyneuropathy that resembles Guillain-Barré syndrome (GBS) is rarely accompanied with nephrotic syndrome, and its underlying immunological mechanisms are unclear. A 56-year-old man presented with simultaneous acute progressive symmetric sensorimotor polyneuropathy and proteinuria. A kidney biopsy revealed focal segmental glomerulosclerosis. Serial electrophysiologic studies showed only a transient proximal conduction block in the median nerve, stimulated somatosensory evoked potential and prolonged terminal latencies of the median and peroneal nerves. The patient's neurologic deficits and kidney dysfunction recovered with corticosteroid treatment. Our case showed that somatosensory evoked potential study can be an important objective tool in the diagnosis of acute polyneuropathy with normal distal nerve conduction and that corticosteroids should be considered in the initial treatment of GBS-resembling polyneuropathy associated with nephrotic syndrome.