Rituximab in refractory chronic inflammatory demyelinating polyneuropathy.

INTRODUCTION: Chronic inflammatory demyelinating polyneuropathy (CIDP) is a disorder in which early effective treatment is important to minimize disability from axonal degeneration. It has been suggested that some patients with CIDP may benefit from rituximab therapy, but there is no definitive evidence for this. METHODS: Baseline and post-rituximab-therapy neuromuscular Medical Research Council (MRC) sum scores, Inflammatory Neuropathy Cause and Treatment (INCAT) disability score, and functional status were assessed in 11 patients with refactory CIDP. RESULTS: The MRC sum score, INCAT disability score, and functional status improved in all patients after rituximab therapy. DISCUSSION: Our study provides evidence of the efficacy of rituximab therapy in at least some patients with CIDP. A placebo-controlled study to assess the effectiveness of rituximab therapy in CIDP with and without nodal antibodies is required to identify disease markers that predict responsiveness.

Immunohistochemistry and electrophysiological findings in swine abattoir workers with immune-mediated polyradiculoneuropathy.

IMPORTANCE: Workers exposed to aerosolized brain in a swine-processing plant developed immune-mediated polyradiculoneuropathy (IP) possibly triggered by an immune response. OBJECTIVE: Immunohistochemistry results were correlated with electrophysiological variables to examine the immunopathogenesis of this disorder. DESIGN/SETTING: Laboratory studies used normal nerve tissue that was exposed to sera from 12 IP patients; 10 exposed controls; and 10 unexposed controls. Clinical and electrophysiological data from IP patients were obtained from medical record reviews. MAIN OUTCOME MEASURES: Analysis included electromyography results of IP patients and nerve conduction studies examining CMAP amplitude, distal motor latency, motor conduction velocity, F-wave latency, sensory nerve action potential amplitude, and sensory nerve conduction velocity. Case and control results were compared relative to distance from exposure. RESULTS: Electrodiagnostic findings revealed prolongation of the distal and f-wave latencies suggestive of demyelination at the level of the nerve root and distal nerve terminals. Immunohistochemical results identified an antibody to the peripheral nerve, with staining at the level of the axolemma. Thus, IP may be a primary axonopathy with secondary paranodal demyelination causing the conduction changes. Staining of the distal and proximal portions of the nerve appears consistent with easier access through the blood-nerve barrier. CONCLUSIONS AND RELEVANCE: IP is an immune-mediated neuropathy related to antibodies to an axon-based antigen on peripheral nerves. Secondary paranodal demyelination is likely. Further studies to identify the primary axonal antigenic target would be useful.

Engineered agrin attenuates the severity of experimental autoimmune myasthenia gravis.

INTRODUCTION: Agrin is essential for the formation and maintenance of neuromuscular junctions (NMJs). NT-1654 is a C-terminal fragment of mouse neural agrin. In this study, we determined the effects of NT-1654 on the severity of experimental autoimmune myasthenia gravis (EAMG). METHODS: EAMG was induced in female Lewis rats by immunization with the Torpedo acetylcholine receptor (tAChR) and complete Freund's adjuvant (CFA). NT-1654 was dissolved in phosphate-buffered saline (PBS) and injected daily subcutaneously into tAChR immunized rats during the first 10 days after immunization, and then every other day for the following 20 days. RESULTS: We showed that NT-1654 attenuated clinical severity, effectively promoted the clustering of AChRs at NMJs, and alleviated the impairment of NMJ transmission and the reduction of muscle-specific kinase (MuSK) in EAMG rats. DISCUSSION: We demonstrated that NT-1654 attenuated clinical severity, effectively promoted the clustering of AChRs at NMJs, and alleviated the impairment of NMJ transmission and the reduction of muscle-specific kinase (MuSK) in EAMG rats. Muscle Nerve 57: 814-820, 2018.

Post-streptococcal vasculopathy with evolution to Degos' disease.

Degos' disease or malignant atrophic papulosis is a rare disseminated occlusive vasculopathy affecting the skin, gastrointestinal tract, central nervous system, and less often other organ systems. The exact etiology of this vasculopathy has not been established. Infections, autoimmune disease and coagulation defects have been proposed as underlying pathogenic mechanisms, but none have been confirmed. Here, we report the clinical, radiological and histopathologic features of Degos' disease in a 41-year-old man following streptococcal throat infection. Prior postulated hypothesis as post-infectious immunologic mechanism may be further supported by this case.

Response to oral supplementation in copper deficiency myeloneuropathy.

Neurological manifestations due to copper deficiency include ataxic myeloneuropathy that resembles subacute combined degeneration due to B12 deficiency. We report our experience in the treatment of 10 patients with copper deficiency myeloneuropathy and conclude that copper supplementation leads to stabilization rather than improvement in the neurological deficits.