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1.
BMC Infect Dis ; 24(1): 491, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38745172

RESUMEN

Brucellosis, a zoonotic disease caused by Brucella species, poses a significant global health concern. Among its diverse clinical manifestations, neurobrucellosis remains an infrequent yet debilitating complication. Here, we present a rare case of neurobrucellosis with unusual presentations in a 45-year-old woman. The patient's clinical course included progressive lower extremity weakness, muscle wasting, and double vision, prompting a comprehensive diagnostic evaluation. Notable findings included polyneuropathy, elevated brucella agglutination titers in both cerebrospinal fluid and blood, abnormal EMG-NCV tests, and resolving symptoms with antibiotic therapy. The clinical presentation, diagnostic challenges, and differentiation from other neurological conditions are discussed. This case underscores the importance of considering neurobrucellosis in regions where brucellosis is prevalent and highlights this rare neurological complication's distinctive clinical and radiological features. Early recognition and appropriate treatment are crucial to mitigate the significant morbidity associated with neurobrucellosis.


Asunto(s)
Brucelosis , Polirradiculoneuropatía , Humanos , Femenino , Brucelosis/diagnóstico , Brucelosis/complicaciones , Brucelosis/tratamiento farmacológico , Persona de Mediana Edad , Polirradiculoneuropatía/diagnóstico , Polirradiculoneuropatía/microbiología , Antibacterianos/uso terapéutico , Brucella/aislamiento & purificación
2.
Eur J Neurol ; 30(2): 501-510, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-35191144

RESUMEN

BACKGROUND AND PURPOSE: A diagnostic score was developed to discriminate anti-myelin-associated-glycoprotein (MAG) neuropathy from chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) and applied it to patients with atypical anti-MAG neuropathy. METHODS: The clinical and electrophysiological features of patients with a diagnosis of typical anti-MAG neuropathy were compared to those of patients with a diagnosis of CIDP. The association of each feature with the diagnosis was assessed in the two groups. Features showing a significant association with the diagnosis were included in a multivariable logistic regression model and adjusted odds ratios were estimated for each feature. A score ranging from 1 to 3 was applied to each feature based on the magnitude of the estimated odds ratios. The score was then applied to patients with a clinical diagnosis of CIDP who also had high anti-MAG antibody titers (CIDP-MAG). RESULTS: Thirty-one anti-MAG neuropathy patients, 45 typical CIDP patients and 16 CIDP-MAG patients were included. Scores in anti-MAG antibody patients ranged from 1 to 5 and in CIDP patients from -7 to -1. Using the score, 4/16 CIDP-MAG patients were diagnosed to have anti-MAG neuropathy and 12/16 patients to have CIDP. Response to intravenous immunoglobulin in the CIDP-MAG patients classified as CIDP was similar to that of definite CIDP patients and higher than that of anti-MAG neuropathy patients. CONCLUSIONS: Our score allowed an accurate discrimination to be made, amongst patients with anti-MAG antibodies, of those affected by CIDP and the patients with anti-MAG neuropathy. This score may help proper treatment to be chosen for patients with anti-MAG antibodies with a CIDP-like presentation.


Asunto(s)
Polirradiculoneuropatía Crónica Inflamatoria Desmielinizante , Polirradiculoneuropatía , Humanos , Polirradiculoneuropatía Crónica Inflamatoria Desmielinizante/terapia , Inmunoglobulina M , Inmunoglobulinas Intravenosas/uso terapéutico , Autoanticuerpos , Glicoproteína Asociada a Mielina , Polirradiculoneuropatía/tratamiento farmacológico
3.
Eur J Neurol ; 30(2): 490-500, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36366904

RESUMEN

BACKGROUND AND PURPOSE: In addition to combined central and peripheral demyelination, other immune diseases could involve both the central nervous system (CNS) and peripheral nervous system (PNS). METHODS: To identify immune-mediated diseases responsible for symptomatic combined central/peripheral nervous system involvement (ICCPs), we conducted a multicentric retrospective study and assessed clinical, electrophysiological, and radiological features of patients fulfilling our ICCP criteria. RESULTS: Thirty patients (20 males) were included and followed during a median of 79.5 months (interquartile range [IQR] = 43-145). The median age at onset was 51.5 years (IQR = 39-58). Patients were assigned to one of four groups: (i) monophasic disease with concomitant CNS/PNS involvement including anti-GQ1b syndrome (acute polyradiculoneuropathy + rhombencephalitis, n = 2), checkpoint inhibitor-related toxicities (acute polyradiculoneuropathy + encephalitis, n = 3), and anti-glial fibrillary acidic protein astrocytopathy (subacute polyradiculoneuropathy and meningoencephalomyelitis with linear gadolinium enhancements, n = 2); (ii) chronic course with concomitant CNS/PNS involvement including paraneoplastic syndromes (ganglionopathy/peripheral hyperexcitability + limbic encephalitis, n = 4); (iii) chronic course with sequential CNS/PNS involvement including POEMS (polyneuropathy, organomegaly, endocrinopathy, monoclonal protein, skin changes) syndrome (polyradiculoneuropathy + strokes, n = 2), histiocytosis (polyradiculoneuropathy + lepto-/pachymeningitis, n = 1), and systemic vasculitis (multineuropathy + CNS vasculitis/pachymeningitis, n = 2); and (iv) chronic course with concomitant or sequential CNS/PNS involvement including combined central and peripheral demyelination (polyradiculoneuropathy + CNS demyelinating lesions, n = 10) and connective tissue diseases (ganglionopathy/radiculopathy/multineuropathy + limbic encephalitis/transverse myelitis/stroke, n = 4). CONCLUSIONS: We diagnosed nine ICCPs. The timing of central and peripheral manifestations and the disease course help determine the underlying immune disease. When antibody against neuroglial antigen is identified, CNS and PNS involvement is systematically concomitant, suggesting a common CNS/PNS antigen and a simultaneous disruption of blood-nerve and blood-brain barriers.


Asunto(s)
Enfermedades Desmielinizantes , Enfermedades del Sistema Inmune , Encefalitis Límbica , Polirradiculoneuropatía , Adulto , Humanos , Masculino , Persona de Mediana Edad , Enfermedades Desmielinizantes/complicaciones , Enfermedades del Sistema Inmune/complicaciones , Encefalitis Límbica/complicaciones , Sistema Nervioso Periférico , Polirradiculoneuropatía/complicaciones , Estudios Retrospectivos , Femenino
4.
Am J Hematol ; 98(12): 1934-1950, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37732822

RESUMEN

DISEASE OVERVIEW: POEMS syndrome is a life-threatening condition due to an underlying plasma cell neoplasm. The major criteria for the syndrome are polyradiculoneuropathy, clonal plasma cell disorder, sclerotic bone lesions, elevated vascular endothelial growth factor, and the presence of Castleman disease. Minor features include organomegaly, endocrinopathy, characteristic skin changes, papilledema, extravascular volume overload, and thrombocytosis. DIAGNOSIS: The diagnosis of POEMS syndrome is made with three of the major criteria, two of which must include polyradiculoneuropathy and clonal plasma cell disorder, and at least one of the minor criteria. RISK STRATIFICATION: Because the pathogenesis of the syndrome is not well understood, risk stratification is limited to clinical phenotype rather than specific molecular markers. Risk factors include low serum albumin, age, pleural effusion, pulmonary hypertension, and reduced estimated glomerular filtration rate. RISK-ADAPTED THERAPY: For those patients with a dominant plasmacytoma, first-line therapy is irradiation. Patients with diffuse sclerotic lesions or disseminated bone marrow involvement should receive systemic therapy. Corticosteroids are temporizing, but alkylators and lenalidomide are the mainstays of treatment, the former either in the form of low-dose conventional therapy or as high-dose conditioning for stem cell transplantation. Thalidomide and bortezomib also have activity, but their benefit needs to be weighed against their risk of exacerbating the peripheral neuropathy. Daratumumab combinations also appear promising based on case series. Prompt recognition and institution of both supportive care measures and therapy directed against the plasma cell result in the best outcomes.


Asunto(s)
Síndrome POEMS , Polirradiculoneuropatía , Humanos , Síndrome POEMS/diagnóstico , Síndrome POEMS/terapia , Síndrome POEMS/patología , Factor A de Crecimiento Endotelial Vascular/metabolismo , Factores de Riesgo , Diagnóstico Diferencial , Polirradiculoneuropatía/diagnóstico
5.
Muscle Nerve ; 65(2): 233-237, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34786740

RESUMEN

INTRODUCTION/AIMS: We aimed to determine whether specific severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) vaccines may be associated with acute-onset polyradiculoneuropathy and if they may result in particular clinical presentations. METHODS: We retrospectively reviewed records of all persons presenting with acute-onset polyradiculoneuropathy from January 1, 2021, to June 30, 2021, admitted to two Neuroscience centers, of the West and North Midlands, United Kingdom. We compared subjects with previous SARS-CoV2 vaccine exposure with a local cohort of persons with acute-onset polyradiculoneuropathy admitted between 2005 and 2019 and compared admission numbers for the studied time frame with that of the previous 3 years. RESULTS: Of 24 persons with acute-onset polyradiculoneuropathy, 16 (66.7%) presented within 4 weeks after first SARS-CoV2 vaccine. Fourteen had received the AstraZeneca vaccine and one each, the Pfizer and Moderna vaccines. The final diagnosis was Guillain-Barré syndrome (GBS) in 12 and acute-onset chronic inflammatory demyelinating polyneuropathy in 4. Among AstraZeneca vaccine recipients, facial weakness in nine persons (64.3%), bulbar weakness in seven (50%), and the bifacial weakness and distal paresthesias GBS variant in three (21.4%), were more common than in historical controls (P = .01; P = .004, and P = .002, respectively). A 2.6-fold (95% confidence interval: 1.98-3.51) increase in admissions for acute-onset polyradiculoneuropathy was noted during the studied time frame, compared to the same period in the previous 3 years. DISCUSSION: Despite a low risk, smaller than that of SARS-CoV2 infection and its complications, exposure to the first dose of AstraZeneca SARS-CoV2 vaccine may be a risk factor for acute-onset polyradiculoneuropathy, characterized by more common cranial nerve involvement.


Asunto(s)
Vacunas contra la COVID-19/efectos adversos , COVID-19 , Síndrome de Guillain-Barré , Polirradiculoneuropatía , COVID-19/prevención & control , Síndrome de Guillain-Barré/inducido químicamente , Síndrome de Guillain-Barré/epidemiología , Humanos , Polirradiculoneuropatía/inducido químicamente , Polirradiculoneuropatía/epidemiología , Estudios Retrospectivos , Reino Unido
6.
Br J Clin Pharmacol ; 88(11): 4941-4949, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36028463

RESUMEN

Reports suggested the potential occurrence of peripheral neuropathies (PN) in patients treated with BRAF (BRAFi) and/or MEK inhibitors (MEKi) for BRAF-activated tumours. We aimed to better characterize these PN. We queried the French pharmacovigilance database for all cases of PN attributed to BRAFi and/or MEKi. Fifteen patients were identified. Two main clinical PN phenotypes were seen. Six patients presented a length-dependent, axonal polyneuropathy: symptoms were mostly sensory and affecting the lower limbs; management and outcome were variable. Nine patients developed a demyelinating polyradiculoneuropathy: symptoms affected the four limbs and included hypoesthesia, weakness and ataxia; cranial nerves were involved in four cases; most patients received intravenous immunoglobulins or glucocorticoids, with variable outcome; one patient was rechallenged with a different BRAFi/MEKi combination with a rapid relapse in symptoms. In conclusion, patients under BRAFi/MEKi therapy may develop treatment-induced PN. Two main phenotypes can occur: a symmetric, axonal, length-dependent polyneuropathy and a demyelinating polyradiculoneuropathy.


Asunto(s)
Enfermedades del Sistema Nervioso Periférico , Polineuropatías , Polirradiculoneuropatía , Glucocorticoides/uso terapéutico , Humanos , Inmunoglobulinas Intravenosas , Quinasas de Proteína Quinasa Activadas por Mitógenos , Recurrencia Local de Neoplasia/tratamiento farmacológico , Enfermedades del Sistema Nervioso Periférico/inducido químicamente , Farmacovigilancia , Polineuropatías/inducido químicamente , Polineuropatías/tratamiento farmacológico , Polirradiculoneuropatía/inducido químicamente , Polirradiculoneuropatía/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/efectos adversos , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Proto-Oncogénicas B-raf/antagonistas & inhibidores
7.
J Med Virol ; 93(2): 766-774, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-32662899

RESUMEN

We report a case series of five patients affected by SARS-CoV-2 who developed neurological symptoms, mainly expressing as polyradiculoneuritis and cranial polyneuritis in the 2 months of COVID-19 pandemic in a city in the northeast of Italy. A diagnosis of Guillain-Barré syndrome was made on the basis of clinical presentation, cerebrospinal fluid analysis, and electroneurography. In four of them, the therapeutic approach included the administration of intravenous immunoglobulin (0.4 g/kg for 5 days), which resulted in the improvement of neurological symptoms. Clinical neurophysiology revealed the presence of conduction block, absence of F waves, and in two cases a significant decrease in amplitude of compound motor action potential compound muscle action potential (cMAP). Four patients presented a mild facial nerve involvement limited to the muscles of the lower face, with sparing of the forehead muscles associated to ageusia. In one patient, taste assessment showed right-sided ageusia of the tongue, ipsilateral to the mild facial palsy. In three patients we observed albuminocytological dissociation in the cerebrospinal fluid, and notably, we found an increase of inflammatory mediators such as the interleukin-8. Peripheral nervous system involvement after infection with COVID-19 is possible and may include several signs that may be successfully treated with immunoglobulin therapy.


Asunto(s)
COVID-19/complicaciones , Síndrome de Guillain-Barré/líquido cefalorraquídeo , Síndrome de Guillain-Barré/diagnóstico , Fenómenos Fisiológicos del Sistema Nervioso , Neuritis/diagnóstico , Anciano , Anciano de 80 o más Años , Ageusia/diagnóstico , Ageusia/virología , COVID-19/líquido cefalorraquídeo , COVID-19/terapia , Parálisis Facial/diagnóstico , Parálisis Facial/virología , Femenino , Síndrome de Guillain-Barré/terapia , Humanos , Inmunización Pasiva , Interleucina-8/líquido cefalorraquídeo , Italia , Masculino , Persona de Mediana Edad , Neuritis/terapia , Neuritis/virología , Polirradiculoneuropatía/diagnóstico , Polirradiculoneuropatía/virología , Sueroterapia para COVID-19
8.
Muscle Nerve ; 63(3): 401-404, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33290607

RESUMEN

BACKGROUND: A distal-predominant demyelinating symmetric pattern is most frequent in patients with neuropathy associated with anti-myelin-associated glycoprotein (MAG) antibodies. The literature however lacks longitudinal data to describe whether this is consistent over time. METHODS: From the Ottawa Neuromuscular Center database, we identified 23 patients with both immunoglobulin M gammopathy and anti-MAG antibodies. For median, ulnar and fibular motor conduction studies, we analyzed distal latency and amplitude, negative peak duration, terminal latency index (TLI), and conduction velocity. For median, ulnar, sural, and superficial fibular sensory conduction studies, we analyzed distal latency and amplitude. Results were compared for the earliest and the latest data sets. RESULTS: The mean time interval between the two assessment points was 6.5 years. Median and ulnar motor nerve conduction studies did not show a significant change for any of the parameters tested. There was disproportionate prolongation of median distal motor latency and reduction in TLI, compared to the ulnar nerve. Deep fibular motor conduction studies showed a marked reduction in amplitudes over time. Sensory potentials were recordable in the upper limb in less than 50% at the first study and less than 25% on the most recent study. There was an even larger attrition of recordable sural and superficial fibular sensory potentials. CONCLUSIONS: Our results highlight the stability of median and ulnar motor conduction study results over a mean observation period of 6.5 years. In contrast, lower limb motor and all sensory potentials show a marked trend toward becoming unrecordable.


Asunto(s)
Autoanticuerpos/inmunología , Nervio Mediano/fisiopatología , Glicoproteína Asociada a Mielina/inmunología , Conducción Nerviosa/fisiología , Polirradiculoneuropatía/fisiopatología , Nervio Cubital/fisiopatología , Anciano , Anciano de 80 o más Años , Progresión de la Enfermedad , Electrodiagnóstico , Femenino , Humanos , Inmunoglobulina M/inmunología , Masculino , Persona de Mediana Edad , Paraproteinemias/complicaciones , Paraproteinemias/inmunología , Polirradiculoneuropatía/complicaciones , Polirradiculoneuropatía/inmunología
9.
Neuropathology ; 41(4): 266-272, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33942396

RESUMEN

Immune-related adverse events (irAEs) commonly involve the gastrointestinal tract, endocrine glands, skin, and liver, and rarely the nervous system. The pathomechanism of irAEs in the nervous system is unclear, and so characterizing these severe toxic effects is a priority, even if irAEs are uncommon in the nervous system. Our patient presented subacute muscle weakness and dysesthesia with colitis as irAEs caused by pembrolizumab, one of the anti-programmed death-1 (PD-1) antibodies. Electromyography revealed abundant fibrillations and fasciculations of upper and lower extremities and severe reduction in motor unit potentials; however, antineutrophil cytoplasmic antibodies, rheumatoid factor, autoantibodies against Hu and Yo, and anti-ganglioside antibodies, such as GQ1b, were undetectable in the serum. Although he was treated with high-dose glucocorticoids, antibiotics, and a monoclonal anti-tumor necrosis factor alpha (TNFα) antibody, he developed colonic perforation. The total colorectal resection was performed, and the resected colon showed mucosal defect and perforation. He died of lung aspergillosis. Postmortem examination revealed CD8-positive lymphocyte infiltration around neurons of dorsal root ganglia. The sciatic nerve displayed the widening of myelin laminae and thinning of myelinated fibers but not a decrease in the density of myelinated nerve fibers. In the sural nerve, the density of myelinated fibers slightly decreased, and some fibers showed less densely myelinated laminae. Drug safety information, including previous randomized trials of anti-PD-1 and anti-cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4) antibodies, showed that patients treated with anti-PD-1 antibodies appeared to have more frequent and severe peripheral neuropathies compared to those in patients who received anti-CTLA-4 antibodies (1.59% vs. 0.69%; Fisher exact test, P < 0.001; three severe events vs. zero severe events). The present results and drug safety information suggest that the pathomechanism of irAEs caused by anti-PD-1 antibodies is different from that by anti-CTLA-4 antibodies. The neurological irAEs might be clues to solving the pathomechanism of irAEs.


Asunto(s)
Enfermedades del Sistema Nervioso Periférico , Polirradiculoneuropatía , Anticuerpos Monoclonales Humanizados/efectos adversos , Humanos , Masculino , Receptor de Muerte Celular Programada 1
10.
J Peripher Nerv Syst ; 25(4): 433-437, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32808377

RESUMEN

Ataxia pancytopenia (ATXPC) syndrome due to gain-of-function pathogenic variants in the SAMD9L gene has been described in 38 patients to date. It is characterized by variable neurological and hematological phenotypes including ataxia, pyramidal signs, cytopenias, and hematological malignancies. Peripheral neuropathy with slowing of conduction velocities has been reported in only two affected individuals. We describe a female with childhood onset neuropathy diagnosed as Charcot-Marie-Tooth disease type 1 with onset of cerebellar ataxia in her 50s. Cerebellar, pyramidal, and neuropathic features were found on examination. Additionally, she also had conjunctival telangiectasia. Nerve conduction studies confirmed a demyelinating neuropathy. MRI brain showed cerebellar atrophy with diffuse white matter hyperintensities. OCT demonstrated global thinning of the retinal nerve fiber layer (RNFL). Full blood count has always been normal. A previously described pathogenic variant in SAMD9L [c.2956C>T p.(Arg986Cys)] was identified on whole exome sequencing. This case extends the previously described phenotype to include conjunctival telangiectasia and RNFL thinning and suggests that ATXPC syndrome should be considered in the differential for inherited demyelinating neuropathies.


Asunto(s)
Ataxia Cerebelosa/genética , Enfermedad de Charcot-Marie-Tooth/genética , Pancitopenia/genética , Proteínas Supresoras de Tumor/genética , Ataxia Cerebelosa/patología , Ataxia Cerebelosa/fisiopatología , Enfermedad de Charcot-Marie-Tooth/patología , Enfermedad de Charcot-Marie-Tooth/fisiopatología , Femenino , Mutación con Ganancia de Función , Humanos , Persona de Mediana Edad , Polirradiculoneuropatía/genética , Polirradiculoneuropatía/patología , Polirradiculoneuropatía/fisiopatología , Síndrome , Telangiectasia/genética , Telangiectasia/patología , Telangiectasia/fisiopatología
11.
Neurol Sci ; 41(2): 341-346, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31650437

RESUMEN

INTRODUCTION: Nerve biopsy has been widely used to investigate patients with peripheral neuropathy, and in many centers, it is still a useful diagnostic tool in this setting. In this study, we reviewed the histopathological spectrum of the nerve biopsies performed in our center in a 30-year period and we analyzed their relevance in the clinical setting. MATERIALS AND METHODS: Retrospective analysis of the retrieved data was done for cases of nerve biopsies performed in our institute between 1988 and 2018. Surgical technique and histopathological analysis were done accordingly to standard protocol. RESULTS: Complete clinical and pathological data were available only for 717 cases. The procedure was generally safe, with only 0.3% superimposed infection. Main pathological results were "unspecific" axonal polyneuropathy (49.8%), vasculitis neuropathy (9.3%), acquired demyelinating neuropathy (8.9%), and Charcot-Marie-Tooth (8.2%). Considering clinical-neurophysiological suspicion of vasculitis, nerve biopsy confirmed the diagnosis in 60.9% of cases. DISCUSSION: In conclusion, for inherited neuropathies, we do not recommend this invasive procedure, but we strongly suggest a genetic test. Conversely, in vasculitic neuropathies or in dysimmune neuropathies not clearly confirmed by neurophysiological examination, nerve biopsy continues to represent a useful and irreplaceable tool.


Asunto(s)
Enfermedad de Charcot-Marie-Tooth/diagnóstico , Polineuropatías/diagnóstico , Nervio Sural/patología , Vasculitis/diagnóstico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Biopsia , Enfermedad de Charcot-Marie-Tooth/patología , Niño , Preescolar , Femenino , Humanos , Masculino , Persona de Mediana Edad , Polineuropatías/etiología , Polineuropatías/patología , Polirradiculoneuropatía/diagnóstico , Polirradiculoneuropatía/patología , Estudios Retrospectivos , Vasculitis/complicaciones , Vasculitis/patología , Adulto Joven
12.
Proc Natl Acad Sci U S A ; 114(18): E3689-E3698, 2017 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-28416698

RESUMEN

Anti-MAG (myelin-associated glycoprotein) neuropathy is a disabling autoimmune peripheral neuropathy caused by monoclonal IgM autoantibodies that recognize the carbohydrate epitope HNK-1 (human natural killer-1). This glycoepitope is highly expressed on adhesion molecules, such as MAG, present in myelinated nerve fibers. Because the pathogenicity and demyelinating properties of anti-MAG autoantibodies are well established, current treatments are aimed at reducing autoantibody levels. However, current therapies are primarily immunosuppressive and lack selectivity and efficacy. We therefore hypothesized that a significant improvement in the disease condition could be achieved by selectively neutralizing the pathogenic anti-MAG antibodies with carbohydrate-based ligands mimicking the natural HNK-1 glycoepitope 1. In an inhibition assay, a mimetic (2, mimHNK-1) of the natural HNK-1 epitope blocked the interaction of MAG with pathogenic IgM antibodies from patient sera but with only micromolar affinity. Therefore, considering the multivalent nature of the MAG-IgM interaction, polylysine polymers of different sizes were substituted with mimetic 2. With the most promising polylysine glycopolymer PL84(mimHNK-1)45 the inhibitory effect on patient sera could be improved by a factor of up to 230,000 per epitope, consequently leading to a low-nanomolar inhibitory potency. Because clinical studies indicate a correlation between the reduction of anti-MAG IgM levels and clinical improvement, an immunological surrogate mouse model for anti-MAG neuropathy producing high levels of anti-MAG IgM was developed. The observed efficient removal of these antibodies with the glycopolymer PL84(mimHNK-1)45 represents an important step toward an antigen-specific therapy for anti-MAG neuropathy.


Asunto(s)
Anticuerpos Neutralizantes , Autoanticuerpos/inmunología , Antígenos CD57/inmunología , Glicoproteína Asociada a Mielina/inmunología , Polirradiculoneuropatía , Animales , Anticuerpos Neutralizantes/inmunología , Anticuerpos Neutralizantes/farmacología , Bovinos , Modelos Animales de Enfermedad , Femenino , Humanos , Masculino , Ratones , Polirradiculoneuropatía/tratamiento farmacológico , Polirradiculoneuropatía/inmunología , Polirradiculoneuropatía/patología
13.
Glia ; 67(4): 571-581, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30378179

RESUMEN

Myelinating Schwann cells undergo irreversible demyelination in many demyelinating neuropathies that show complete demyelination of the internode. Dedifferentiation, reprogramming, and myelin clearance processes-which are specifically discussed in this article-appear to be shared by various demyelinating peripheral conditions, such as Wallerian degeneration, immune-mediated, and toxic demyelinating diseases. We propose to introduce the concept of the "demyelinating Schwann cell (DSC)" as a novel cell phenotype, which has specific properties required for myelin sheath clearance. We anticipate that the introduction of the DSC concept will provide a significant advance in understanding the pathophysiological mechanisms of demyelinating peripheral neuropathies.


Asunto(s)
Polirradiculoneuropatía/patología , Células de Schwann/patología , Animales , Autofagia , Humanos , Fagocitosis , Células de Schwann/ultraestructura , Degeneración Walleriana/patología
14.
Radiology ; 293(1): 125-133, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31429680

RESUMEN

Background Traumatic brachial plexus injuries affect 1% of patients involved in major trauma. MRI is the best test for traumatic brachial plexus injuries, although its ability to differentiate root avulsions (which require urgent reconstructive surgery) from other types of nerve injury remains unknown. Purpose To evaluate the accuracy of MRI for diagnosing root avulsions in adults with traumatic brachial plexus injuries. Materials and Methods For this systematic review, MEDLINE and Embase were searched from inception to August 20, 2018. Studies of adults with traumatic nonpenetrating unilateral brachial plexus injuries were included. The target condition was root avulsion. The index test was preoperative MRI, and the reference standard was surgical exploration. A bivariate meta-analysis was used to estimate summary sensitivities and specificities of MRI for avulsion. Results Eleven studies of 275 adults (mean age, 27 years; 229 men) performed between 1992 and 2016 were included. Most participants had been injured in motorcycle collisions (84%). All studies were at risk of bias, and there were high applicability concerns for the index test (ie, MRI) in four studies given the lack of diagnostic criteria, inadequate descriptions of pulse sequences, and multiplicity of reporting radiologists. Overall, 72% of patients with brachial plexus injuries had at least one root avulsion (interquartile range [IQR]: 53%-86%); meta-analysis of patient-level data was not performed because of sparse and heterogeneous data. With the nerve root as the unit of analysis, 583 of 918 roots were avulsed (median, 55%; IQR: 38%-71%); the mean sensitivity of MRI for root avulsion was 93% (95% confidence interval [CI]: 77%, 98%) with a mean specificity of 72% (95% CI: 42%, 90%). Conclusion On the basis of limited data, MRI offers modest diagnostic accuracy for traumatic brachial plexus root avulsion(s), and early surgical exploration should remain as the preferred method of diagnosis. Published under a CC BY 4.0 license. Online supplemental material is available for this article.


Asunto(s)
Plexo Braquial/diagnóstico por imagen , Plexo Braquial/lesiones , Imagen por Resonancia Magnética/métodos , Polirradiculoneuropatía/diagnóstico por imagen , Humanos , Sensibilidad y Especificidad , Raíces Nerviosas Espinales/diagnóstico por imagen , Raíces Nerviosas Espinales/lesiones
15.
Glia ; 66(11): 2299-2315, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30417431

RESUMEN

Neuroprotective effects of erythropoietin (EPO) on peripheral nerve injury remain uncertain. This study investigated the efficacy of EPO in attenuating median nerve chronic constriction injury (CCI)-induced neuropathy. Animals received an intraneural injection of EPO at doses of 1,000, 3,000, or 5,000 units/kg 15 min before median nerve CCI. Afterwards, the behavioral and electrophysiological tests were conducted. Immunohistochemistry and immunoblotting were used for qualitative and quantitative analysis of microglial and mitogen-activated protein kinases (MAPKs), including p38, JNK, and ERK, activation. Enzyme-linked immunosorbent assay and microdialysis were applied to measure pro-inflammatory cytokine and glutamate responses, respectively. EPO pre-treatment dose-dependently ameliorated neuropathic pain behavior, decreased microglial and MAPKs activation, and diminished the release of pro-inflammatory cytokines and glutamate in the ipsilateral cuneate nucleus after CCI. Moreover, EPO pre-treatment preserved myelination of the injured median nerve on morphological investigation and suppressed injury-induced discharges. We also observed that EPO receptor (EPOR) expression was up-regulated in the injured nerve after CCI. Double immunofluorescence showed that EPOR was localized to Schwann cells. Furthermore, siRNA-mediated knockdown of EPOR expression eliminated the therapeutic effects of EPO on attenuating the microglial and MAPKs activation, pro-inflammatory cytokine responses, injury discharges, and neuropathic pain behavior in CCI rats. In conclusion, binding of EPO to its receptors on Schwann cells maintains myelin integrity and blocks ectopic discharges in the injured median nerve, that in the end contribute to attenuation of neuropathic pain via reducing glutamate release from primary afferents and inhibiting activation of microglial MAPKs and production of pro-inflammatory cytokines.


Asunto(s)
Eritropoyetina/uso terapéutico , Microglía/metabolismo , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Neuralgia/tratamiento farmacológico , Polirradiculoneuropatía/tratamiento farmacológico , Receptores de Eritropoyetina/metabolismo , Células de Schwann/metabolismo , Potenciales de Acción/efectos de los fármacos , Animales , Citocinas/metabolismo , Modelos Animales de Enfermedad , Regulación de la Expresión Génica/efectos de los fármacos , Hiperalgesia/tratamiento farmacológico , Masculino , Nervio Mediano/patología , Microglía/efectos de los fármacos , Neuralgia/etiología , Umbral del Dolor/efectos de los fármacos , Enfermedades del Sistema Nervioso Periférico/complicaciones , Fosforilación/efectos de los fármacos , Polirradiculoneuropatía/etiología , ARN Interferente Pequeño/uso terapéutico , Ratas , Ratas Sprague-Dawley , Receptores de Eritropoyetina/genética , Células de Schwann/efectos de los fármacos , Transducción de Señal/efectos de los fármacos
16.
Muscle Nerve ; 57(1): 150-156, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28093780

RESUMEN

INTRODUCTION: Autosomal dominant haploinsufficiency of GATA2 causes monocytopenia and natural killer cell lymphopenia, resulting in predisposition to mycobacterial, fungal, and viral infections. METHODS: Herein we report on the clinical, serologic, electrophysiologic, and pathologic evaluations of a 29-year-old woman with GATA2 haploinsufficiency and active Epstein-Barr virus (EBV) infection complicated by subacute painful neuropathy. RESULTS: Nerve conduction and electromyography studies showed predominantly demyelinating sensorimotor polyradiculoneuropathy. Lumbar spine MRI showed thickening and enhancement of the cauda equina nerve roots. Serum and cerebrospinal fluid anti-IgG and IgM EBV capsid and nucleic acid antibodies were positive. Sural nerve biopsy showed microvasculitis and an increased frequency of fibers with segmental demyelination. Intravenous immunoglobulin and steroids improved the patient's neuropathy. CONCLUSION: GATA2 mutation-related immunodeficiency may predispose to EBV-associated subacute demyelinating polyradiculoneuropathy by both viral susceptibility and immune dysregulation. In patients who present in this manner, immunodeficiency syndromes should be considered when lymphomatous infiltration is excluded. Immunotherapy can be helpful. Muscle Nerve 57: 150-156, 2018.


Asunto(s)
Infecciones por Virus de Epstein-Barr/complicaciones , Factor de Transcripción GATA2/genética , Haploinsuficiencia/genética , Polirradiculoneuropatía/complicaciones , Polirradiculoneuropatía/genética , Adulto , Anticuerpos Antiidiotipos , Enfermedades Autoinmunes del Sistema Nervioso/patología , Biopsia , Electromiografía , Infecciones por Virus de Epstein-Barr/diagnóstico por imagen , Femenino , Humanos , Síndromes de Inmunodeficiencia , Imagen por Resonancia Magnética , Conducción Nerviosa , Examen Neurológico , Polirradiculoneuropatía/diagnóstico por imagen , Nervio Sural/patología
19.
Eur Neurol ; 80(5-6): 304-310, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30889595

RESUMEN

Intravenous immunoglobulin therapy is FDA approved for the immune-mediated peripheral nerve disorders Guillain-Barre syndrome, chronic inflammatory demyelinating polyneuropathy, and multifocal motor neuropathy. Immunoglobulin therapy has been used increasingly with significant efficacy in the treatment of patients with disabling autoimmune forms of dysautonomia, which are most often small fiber (autonomic and/or sensory) polyneuropathies. It is recognized by most who treat these disorders, however, that patients with autonomic dysfunction treated with intravenous immunoglobulin therapy develop aseptic meningitis or severe lingering headache more frequently than other patient populations when this therapy is dosed in the traditional fashion. We discuss our combined 27 years of experience with the use of immunoglobulin and other immune modulatory therapy in patients with autoimmune small fiber polyneuropathy.


Asunto(s)
Inmunoglobulinas Intravenosas/uso terapéutico , Polirradiculoneuropatía/tratamiento farmacológico , Humanos , Inmunización Pasiva , Inmunoglobulinas Intravenosas/efectos adversos
20.
Georgian Med News ; (Issue): 81-85, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29578430

RESUMEN

The article presents an analysis of the clinical occurrence of development of chronic polyradiculoneuropathy associated with monoclonal IgG/k (kappa) gammopathy of the undetermined significance. The peculiarity of this occurrence is the uniqueness of the development of the symptoms which are characteristic of tabes dorsalis in this pathology with episodic severe visceral crises and also with ganglionopathy. The example describes the clinical polymorphism of the course of visceral crises, the problems of their diagnosis and as a consequence of inadequate treatment with the development of severe social maladaptation. The importance of timely diagnosis and treatment of such conditions is discussed.


Asunto(s)
Enfermedades del Nervio Facial/diagnóstico , Gammopatía Monoclonal de Relevancia Indeterminada/diagnóstico , Polirradiculoneuropatía/diagnóstico , Tabes Dorsal/diagnóstico , Adulto , Enfermedades del Nervio Facial/complicaciones , Enfermedades del Nervio Facial/fisiopatología , Enfermedades del Nervio Facial/terapia , Femenino , Humanos , Inmunoglobulina G/sangre , Midodrina/uso terapéutico , Gammopatía Monoclonal de Relevancia Indeterminada/complicaciones , Gammopatía Monoclonal de Relevancia Indeterminada/fisiopatología , Gammopatía Monoclonal de Relevancia Indeterminada/terapia , Plasmaféresis , Polirradiculoneuropatía/complicaciones , Polirradiculoneuropatía/fisiopatología , Polirradiculoneuropatía/terapia , Pregabalina/uso terapéutico , Tabes Dorsal/complicaciones , Tabes Dorsal/fisiopatología , Tabes Dorsal/terapia , Tramadol/uso terapéutico
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