Clinical characteristics of patients with autoimmune nodopathy with anti-neurofascin155 antibodies.

Background: According to the latest guidelines on chronic inflammatory demyelinating polyradiculoneuropathy (CIDP), patients with CIDP with anti-neurofascin 155 (NF155) antibodies are referred to as autoimmune nodopathy (AN), an autoimmune disorder distinct from CIDP. We aimed to compare the clinical data of patients with AN with anti-NF155 antibodies with those of anti-NF155 antibodies-negative patients with CIDP, and to summarize the clinical characteristics of patients with AN with anti-NF155 antibodies. Methods: Nine patients with AN with anti-NF155 antibodies and 28 serologically negative patients with CIDP were included in this study. Diagnosis was made according to the diagnostic criteria in the European Academy of Neurology (EAN)/Peripheral Nerve Society (PNS) guidelines on CIDP published in 2021. Demographics, clinical manifestations, electrophysiological examination, cerebrospinal fluid (CSF) tests, and response to treatment were retrospectively analyzed. Results: Compared with serologically negative patients with CIDP, those patients with AN with anti-NF155 antibodies were younger (p=0.007), had a younger onset age (p=0.009), more frequent ataxia (p=0.019), higher CSF protein levels (p=0.001), and more frequent axon damage in electrophysiology (p=0.025). The main characteristics of patients with AN with anti-NF155 antibodies include younger age and onset age, limb weakness, sensory disturbance, ataxia, multiple motor-sensory peripheral neuropathies with demyelination and axonal damage on electrophysiological examination, markedly elevated CSF protein levels, and varying degrees of response to immunotherapy. Conclusions: Patients with AN with anti-NF155 antibodies differed from serologically negative patients with CIDP in terms of clinical characteristics. When AN is suspected, testing for antibodies associated with the nodes of Ranvier is essential for early diagnosis and to guide treatment.

Anti-neurofascin-155 antibody mediated a distinct phenotype of chronic inflammatory demyelinating polyradiculoneuropathy.

BACKGROUND: To investigate Ranvier's autoantibodies prevalence and isotypes in various peripheral neuropathy variants, compare clinical features between seronegative and seropositive patients, and elucidate immune mechanisms underlying antibody generation. METHODS: Antibodies against anti-neurofascin-155 (NF155), NF186, contactin-1 (CNTN1), CNTN2, contactin-associated protein 1 (CASPR1), and CASPR2 were identified through cell-based assays. Plasma cytokines were analyzed in anti-NF155 antibody-positive chronic inflammatory demyelinating polyneuropathy (NF155+ CIDP) and Ranvier's antibodies-negative CIDP (Ab- CIDP) patients using a multiplexed fluorescent immunoassay, validated in vitro in a cell culture model. RESULTS: In 368 plasma samples, 50 Ranvier's autoantibodies were found in 45 individuals, primarily in CIDP cases (25 out of 69 patients) and in 10 out of 122 Guillain-Barré syndrome patients. Anti-NF155 and CNTN1-IgG were exclusive to CIDP. Fourteen samples were NF155-IgG, primarily IgG4 subclass, linked to CIDP features including early onset, tremor, sensory disturbance, elevated CSF protein, prolonged motor latency, conduction block, and poor treatment response. NF155-IgG had low sensitivity (20.28%) but high specificity (100%) for CIDP, rising to 88.88% with tremor and prolonged motor latency. Cytokine profiling in NF155+ CIDP revealed distinct immune responses involving helper T cells, toll-like receptor pathways. Some NF155+ CIDP patients had circulating NF155-specific B cells producing NF155-IgG without antigen presence, suggesting therapeutic potential. CONCLUSION: The study emphasizes the high specificity and sensitivity of NF155-IgG for diagnosing CIDP characterized by distinctive features. Further investigation into circulating NF155-specific B cell phenotypes may pave the way for B cell directed therapy.

Anti-neurofascin 155 Antibody-positive Neuropathy in a Human Immunodeficiency Virus-infected Patient.

Human immunodeficiency virus (HIV)-associated neuropathy is a common complication of HIV infection and has several clinical subtypes. HIV-associated chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is a demyelinating neuropathy whose clinical features are known to differ from those of CIDP in the HIV-uninfected population. We herein report a case of CIDP in an HIV-infected patient who was finally diagnosed with anti-neurofascin 155 (NF155) antibody-positive neuropathy. The clinical features, including clinical findings and therapeutic responses, were typical of paranodal antibody-mediated neuropathy. To our knowledge, this is the first case of anti-NF155 antibody-associated neuropathy in an HIV-infected patient.

Anti-rituximab antibodies in patients with refractory autoimmune nodopathy with anti-neurofascin-155 antibody.

Background: Recent studies have reported that similar to other IgG4 autoimmune diseases, such as muscle-specific kinase antibody-associated myasthenia gravis, most anti-neurofascin-155 (anti-NF155) nodopathies respond well to rituximab treatment, regardless of the dosage. However, there are still a few patients for which rituximab is ineffective for unknown reasons. Currently, there are no studies on the mechanism of ineffective treatment with rituximab. Methods: A 33-year-old Chinese man presenting with numbness, tremor, and muscle weakness for 4 years was recruited for this study. Anti-NF155 antibodies were identified by cell-based assay and confirmed by immunofluorescence assay on teased fibers. The anti-NF155 immunoglobulin (IgG) subclasses were also detected by immunofluorescence assay. Anti-rituximab antibodies (ARAs) were quantitatively analyzed using enzyme-linked immunosorbent assay (ELISA), and peripheral B cell counts were determined by flow cytometry. Results: The patient exhibited anti-NF155 IgG4-antibody positivity. After the first round of rituximab infusion, the patient showed stratified outcomes with improvements in numbness, muscle weakness and ambulation. However, after three rounds of rituximab infusion, the patient's symptoms deteriorated, and the numbness, tremor and muscle weakness returned. No obvious improvement was found after plasma exchange and another round of rituximab treatment. 14 days after the last treatment with rituximab, ARAs were detected. And the titers gradually decreased on day 28 and 60 but remained higher than normal. Peripheral CD19+ B cell counts were less than 1% within the 2-month period following the final rituximab administration. Conclusions: In this study, ARAs presented in a patient with anti-NF155 nodopathy undergoing rituximab treatment and showed an unfavorable impact on rituximab efficacy. This is the first case to report the occurrence of ARAs in patients with anti-NF155 antibodies. We suggest that ARAs should be tested early during the initial intervention, especially in patients who respond poorly to rituximab treatment. In addition, we believe it is necessary to investigate the association between ARAs and B cell counts, their effect on clinical efficacy, and their potential adverse reactions in a larger cohort of patients with anti-NF155 nodopathy.

Polirradiculoneuropatía desmielinizante inflamatoria crónica con anticuerpos antineurofascina-155: primer reporte de caso en Perú / Chronic inflammatory demyelinating polyradiculoneuropathy with antineurofascin-155 antibodies: A first case report in Peru

La polirradiculoneuropatía desmielinizante inflamatoria crónica, es un grupo de neuro-patías periféricas inmunomediadas clínicamente heterogéneas que comparten manifes-taciones neurofisiológicas de desmielinización y disociación albuminocitológica. Se distinguen una forma típica y variantes atípicas, algunas asociadas a anticuerpos con-tra proteínas del nodo de Ranvier, como la neurofascina- 155. Presentamos el caso de un varón de 38 años, que acudió por cuadro de ocho meses de evolución, caracterizado por parestesias y debilidad progresiva de cuatro extremidades, asociado a diplopía y disfagia. El paciente estaba despierto, con cuadriparesia flácida simétrica de predominio distal, hipotrofia en dorso y palma de ambas manos, arreflexia generalizada, temblor postural de baja frecuencia y alta amplitud en miembros superiores de predominio izquierdo, dismetría apendicular, adiadococinesia, oftalmoparesia a la dextroversión en ojo dere-cho, reflejo nauseoso ausente, marcha atáxica con aumento de base de sustentación y signo de Romberg positivo. El líquido cefalorraquideo mostró disociación albuminocitológica y la electromiografía fue compatible con polineuropatía sensitivo- motora primariamente desmielinizante. Por la sospecha clínica, solicitamos anticuerpos antineurofascina- 155, que resultaron positivos. Recibió tratamiento con metilprednisolona a dosis de un gramo al día durante cinco días, seguido de un miligramo por kilogramo durante tres meses de prednisona, con disminución progresiva con lo que mejoró la diplopía y la disfagia, sin mejoría de la fuerza en extremidades e incluso empeoramiento de la funcionabilidad. Por esta razón se inició tratamiento con rituximab en dosis de dos gramos presentando una notable mejoría en la fuerza muscular distal, el temblor, la estabilidad de la marcha, coordinación y de su funcionabilidad medida con la escala de Rankin modificado.

Chronic inflammatory demyelinating polyradiculoneuropathy is a clinically heterogeneous group of immune- mediated peripheral neuropathies that share neurophysiological manifesta-tions of demyelination and albuminocytologic dissociation. There are typical and atypical variants of this disease, some associated with antibodies against proteins of the node of Ranvier, such as neurofascin- 155. We present the case of a 38- year- old male who presented with an eight- month history of par-esthesia and progressive weakness of four limbs associated with diplopia and dysphagia. The patient was conscious, with symmetric flaccid quadriparesis of distal predominance, hyp-otrophy in the dorsum and palm of both hands, generalized areflexia, postural low frequency, and high amplitude tremor in upper limbs of left predominance, appendicular dysmetria, dys-diadochokinesia, ophthalmoparesis to dextroversion in the right eye, absent gag reflex, ataxic gait with an increased base of support and positive Romberg's sign. Cerebrospinal fluid showed albuminocytologic dissociation, and electromyography was com-patible with primarily demyelinating sensory- motor polyneuropathy. Due to clinical suspicion, we requested anti- neurofascin- 155 antibodies, which tested positive. The patient was treated with methylprednisolone at a dose of one gram per day for five days, followed by one milligram per kilogram for three months of prednisone, with progressive de-crease, which improved diplopia and dysphagia, with no effect on limb strength and even worsening of function. For this reason, treatment with rituximab was started in doses of two grams, presenting a substantial improvement in distal muscle strength, tremor, gait stability, coordination, and functionality measured with the modified Rankin scale.

A case report of a successful multidisciplinary management of an abdominal pregnancy / Manejo multidisciplinario exitoso del embarazo abdominal. Reporte de un caso peruano

Abdominal pregnancy is defined as one that occurs outside of the uterus and fallopian tubes in the abdominal cavity. We present the case of a 30-year-old Peruvian female patient from Lima with a surgical history of exploratory laparotomy due to tubal ectopic pregnancy and appendectomy without further relevant personal or family histories. She attended the emergency room of a social security hospital in Peru with a referral from a district hospital and a diagnosis of abdominal pregnancy at 14 weeks of gestational age without previous prenatal controls. Symptomatology at hospital admission was colic-type abdominal pain in the hypogastrium without vaginal bleeding, fluid loss or fever. During hospitalization, she underwent an exploratory laparotomy with embolization of the uterine artery, left salpingectomy, and removal of the abdominal ectopic pregnancy. The evolution was favorable after the surgery, and she was discharged. Without further complications, she continues her controls at the obstetrics and gynecology outpatient service without complications.

El embarazo abdominal es aquel embarazo que ocurre fuera del útero y las trompas de Falopio en la cavidad abdominal. Presentamos el caso de una paciente peruana de 30 años proveniente de la ciudad de Lima, con antecedentes quirúrgicos de laparotomía exploradora por embarazo ectópico tubárico y apendicectomía, sin otras patologías ni antecedentes familiares de importancia. La paciente acude al servicio de urgencias de un hospital del seguro social en Perú derivada de un hospital distrital con diagnóstico de embarazo abdominal a las 14 semanas de edad gestacional, sin controles prenatales previos. La sintomatología al ingreso hospitalario fue dolor abdominal de tipo cólico a nivel del hipogastrio, sin sangrado vaginal, pérdida de líquidos o fiebre. Durante su hospitalización se le realizó una laparotomía exploratoria con embolización de la arteria uterina, salpingectomía izquierda y extracción del embarazo abdominal. La evolución fue favorable tras la intervención quirúrgica, siendo dada de alta. Actualmente continúa sus controles en el servicio de consulta externa del servicio de ginecología y obstetricia sin complicaciones.

Chronic inflammatory demyelinating polyradiculoneuropathy with antineurofascin-155 antibodies: A first case report in Peru. / Polirradiculoneuropatía desmielinizante inflamatoria crónica con anticuerpos antineurofascina-155: primer reporte de caso en Perú.

Chronic inflammatory demyelinating polyradiculoneuropathy is a clinically heterogeneous group of immune- mediated peripheral neuropathies that share neurophysiological manifesta-tions of demyelination and albuminocytologic dissociation. There are typical and atypical variants of this disease, some associated with antibodies against proteins of the node of Ranvier, such as neurofascin- 155. We present the case of a 38- year- old male who presented with an eight- month history of par-esthesia and progressive weakness of four limbs associated with diplopia and dysphagia. The patient was conscious, with symmetric flaccid quadriparesis of distal predominance, hyp-otrophy in the dorsum and palm of both hands, generalized areflexia, postural low frequency, and high amplitude tremor in upper limbs of left predominance, appendicular dysmetria, dys-diadochokinesia, ophthalmoparesis to dextroversion in the right eye, absent gag reflex, ataxic gait with an increased base of support and positive Romberg's sign. Cerebrospinal fluid showed albuminocytologic dissociation, and electromyography was com-patible with primarily demyelinating sensory- motor polyneuropathy. Due to clinical suspicion, we requested anti- neurofascin- 155 antibodies, which tested positive. The patient was treated with methylprednisolone at a dose of one gram per day for five days, followed by one milligram per kilogram for three months of prednisone, with progressive de-crease, which improved diplopia and dysphagia, with no effect on limb strength and even worsening of function. For this reason, treatment with rituximab was started in doses of two grams, presenting a substantial improvement in distal muscle strength, tremor, gait stability, coordination, and functionality measured with the modified Rankin scale.

La polirradiculoneuropatía desmielinizante inflamatoria crónica, es un grupo de neuro-patías periféricas inmunomediadas clínicamente heterogéneas que comparten manifes-taciones neurofisiológicas de desmielinización y disociación albuminocitológica. Se distinguen una forma típica y variantes atípicas, algunas asociadas a anticuerpos con-tra proteínas del nodo de Ranvier, como la neurofascina- 155. Presentamos el caso de un varón de 38 años, que acudió por cuadro de ocho meses de evolución, caracterizado por parestesias y debilidad progresiva de cuatro extremidades, asociado a diplopía y disfagia. El paciente estaba despierto, con cuadriparesia flácida simétrica de predominio distal, hipotrofia en dorso y palma de ambas manos, arreflexia generalizada, temblor postural de baja frecuencia y alta amplitud en miembros superiores de predominio izquierdo, dismetría apendicular, adiadococinesia, oftalmoparesia a la dextroversión en ojo dere-cho, reflejo nauseoso ausente, marcha atáxica con aumento de base de sustentación y signo de Romberg positivo. El líquido cefalorraquideo mostró disociación albuminocitológica y la electromiografía fue compatible con polineuropatía sensitivo- motora primariamente desmielinizante. Por la sospecha clínica, solicitamos anticuerpos antineurofascina- 155, que resultaron positivos. Recibió tratamiento con metilprednisolona a dosis de un gramo al día durante cinco días, seguido de un miligramo por kilogramo durante tres meses de prednisona, con disminución progresiva con lo que mejoró la diplopía y la disfagia, sin mejoría de la fuerza en extremidades e incluso empeoramiento de la funcionabilidad. Por esta razón se inició tratamiento con rituximab en dosis de dos gramos presentando una notable mejoría en la fuerza muscular distal, el temblor, la estabilidad de la marcha, coordinación y de su funcionabilidad medida con la escala de Rankin modificado.

Case report: Autoimmune nodopathy with concurrent serum and CSF IgG4 anti-neurofascin 155 antibodies.

Objective: To report a case of autoimmune nodopathy (AN) with concurrent serum and CSF immunoglobulin (Ig)G4 anti-neurofascin 155 (NF155) and anti-GD1b antibodies. Methods: A 20-year-old male presented distal weakness of the 4 limbs, hypoesthesia, absent tendon reflexes and sensory ataxia. Nerve conduction studies (NCS), MRI, and autoantibody tests were performed. Results: NCS revealed a diffuse demyelinating neuropathy in the peripheral nerve with motor and sensory involvement. MRI of the cervical and lumbar plexus showed diffuse enlargement. IgG4 anti-NF155 antibodies in both serum and CSF and IgG anti-GD1b antibodies in serum were positive. After treatment with IVIg, rituximab, and plasma exchange, the titer of the patient's anti-NF155 antibodies decreased, but symptoms did not significantly improve. Discussion: This patient presented a typical clinical feature of AN with serum and CSF anti-NF155 antibodies and serum anti-GD1b antibodies coexistent but poor response to IVIg, rituximab and plasma exchange. Early detection of antibodies may be helpful in both diagnosis and therapy of the disease. And prospective studies are necessary to demonstrate the potential role of anti-NF155 antibodies in CSF and help further understand this complex and heterogeneous disease.

Clinical features of Guillain-Barré syndrome with anti-neurofascin 155 antibody.

OBJECTIVE: Anti-neurofascin 155 (NF155) antibody has been discovered in chronic demyelinating conditions. However, the positive rate and clinical description were insufficient in acute demyelinating conditions, such as Guillain-Barré syndrome (GBS). This study aimed to explore the positive rate of anti-NF155 antibody in GBS patients and determine whether there were unique clinical characteristics in these patients. MATERIALS & METHODS: Serum anti-NF155 antibody was detected from 94 GBS patients and 50 sex- and age-matched healthy controls using cell-based assay and tissue-based assay with immunostaining of mouse teased sciatic nerve fibers. Clinical characteristics, laboratory data, and electrophysiology examinations were retrospectively collected. RESULTS: Seven of 94 (7.45%) GBS patients were positive for anti-NF155 antibody, and the main IgG subclass was IgG1. Compared with anti-NF155 antibody-negative GBS patients, anti-NF155 antibody-positive GBS patients had a higher GBS disability score at nadirs (p = .010), higher modified Erasmus GBS outcome score (p = .022), higher rate of abnormal compound motor action potential (CMAP) amplitude (p = .002), higher frequency of prolonged F-wave latency (p < .001), lower frequency of abnormal sensory conduction velocity (p < .001) and sensory nerve action potential amplitude (p < .001), more axonal type (p = .040), and poorer therapeutic effect (p = .017). CONCLUSIONS: Anti-NF155 antibody exists in a small portion of GBS patients. Anti-NF155 antibody-positive GBS patients possibly have a more severe clinical course, less sensory nerves involved, higher proportion of axonal type, poorer therapeutic effect, and worse prognosis, but the pathogenicity of the anti-NF155 antibody in GBS needs further study.

The prevalence of anti-neurofascin-155 antibodies in patients with neuromyelitis optica spectrum disorders.

Anti-neurofascin-155 (NF155) antibodies have been observed in two cases with neuromyelitis optica spectrum disorders (NMOSD). This study investigated the prevalence of anti-NF155 antibodies in patients with NMOSD and the clinical features of anti-NF155 antibody-positive patients. Sera from 129 patients with NMOSD were screened with anti-NF155 antibodies by cell-based assay (CBA) and re-examined using immunostaining of teased mouse sciatic nerve fibres. Fifty-six patients with multiple sclerosis (MS) and 50 healthy controls (HC) were also enrolled for detecting anti-NF155 antibodies. A total of 12.40% (16 of 129) of patients with NMOSD were positive for anti-NF155 antibodies confirmed by both CBA and immunostaining. Immunoglobulin (Ig) G1 was the predominant subclass. However, none of 56 MS patients or 50 HC were positive for anti-NF155 antibodies. Anti-NF155 antibody-positive NMOSD patients had a higher proportion of co-existing with autoimmune diseases (p < 0.001) and higher positive rates of serum non-organ-specific autoantibodies, including anti-SSA antibodies (p < 0.001), anti-SSB antibodies (p = 0.008), anti-Ro-52 antibodies (p < 0.001) and rheumatoid factor (p < 0.001). Five anti-NF155 antibody-positive NMOSD patients who took part in the nerve conduction study showed mildly abnormal results. Differences in some nerve conduction study parameters were observed between anti-NF155 antibody-positive and negative patients. Anti-NF155 antibodies occurred in a small proportion of NMOSD patients. Anti-NF155 antibody-positive NMOSD patients tended to co-exist with autoimmune diseases.

Anti-neutral glycolipids antibody-positive combined central and peripheral demyelination mimicking encephalomyeloradiculoneuropathy phenotype.

We herein report the first combined central and peripheral demyelination (CCPD) case originally diagnosed as multifocal acquired demyelinating sensory and motor neuropathy followed by CNS impairments with a long lag time (160 days after first attack). The anti-neutral glycolipids antibodies, especially anti-lactosylceramide antibodies but not anti-NF155 antibodies typical for CCPD were detected in the acute phase of sera and cerebrospinal fluid (CSF) and disappeared in the recovery phase. This case strongly illustrated the significance of examining anti-neutral glycolipids antibodies in future anti-NF 155 antibodies-negative CCPD cases.