Síndrome de Vulpian-Bernhardt. Frecuencia, características clínicas y electrofisiológicas en un centro de atención de tercer nivel en México / Vulpian-Bernhardt syndrome. Its frequency and clinical and electrophysiological features in a tertiary care centre in Mexico

INTRODUCCIÓN: El síndrome de Vulpian-Bernhardt (SVB) es un fenotipo clínico atípico e infrecuente de la esclerosis lateral amiotrófica (ELA) que condiciona un importante retraso diagnóstico, por lo que reconocer sus características clínicas y electrofisiológicas tiene relevancia. MATERIALES Y MÉTODOS: Estudio retrospectivo y transversal. Se revisaron los expedientes clínicos de pacientes con diagnóstico de ELA en el período de enero de 2017 a diciembre de 2019. Se incluyeron los que cumplían criterios para SVB para describir su frecuencia, características clínicas y electrofisiológicas. RESULTADOS: Veinte pacientes (15,8%) cumplieron los criterios para el SVB; el 55% eran mujeres; la edad de inicio de los síntomas era de 46,6 ± 12,9 años; presentaba tabaquismo el 40%; la mediana de retraso del diagnóstico fue de 24 (12-96) meses; la mediana en afectarse un segundo segmento corporal fue de 24 (12-132) meses, que fue el lumbosacro en el 65%; el promedio en la escala Revised Amyotrophic Lateral Sclerosis Functional Rating Scale fue de 27 ± 7 puntos; el 45% cumplía los criterios de El Escorial para ELA definida en el momento del diagnóstico y el 58,8%, los de Awaji. Se contó con 19 estudios de neuroconducción y 17 electromiogramas, y se encontró una razón abductor digiti minimi-abductor pollicis brevis (APB/ADM) < 0,6 en el 63% (mano dividida). CONCLUSIONES: Existe un retraso importante en el diagnóstico de enfermedades de la motoneurona en general y de SVB en particular. Calcular la razón APB/ADM y aplicar los criterios de Awaji en el estudio de electrofisiología puede ser de gran ayuda para aumentar la certeza diagnóstica en esta entidad clínica

INTRODUCTION: Vulpian-Bernhardt syndrome (VBS) is an atypical rare clinical phenotype of amyotrophic lateral sclerosis (ALS) that causes a significant delay in diagnosis, and thus it is important to recognise its clinical and electrophysiological features. MATERIALS AND METHODS: Retrospective cross-sectional study. We reviewed the clinical records of patients diagnosed with ALS in the period from January to December 2019. Those meeting criteria for VBS were included so as to describe their frequency as well as their clinical and electrophysiological features. RESULTS: Twenty patients (15.8%) met criteria for VBS; 55% were female; age at onset of symptoms was 46.6 ± 12.9 years; 40% were smokers; median delay in diagnosis was 24 (12-96) months; median time to involvement of the second body segment was 24 (12-132) months, which was lumbosacral in 65%; mean Revised Amyotrophic Lateral Sclerosis Functional Rating Scale score was 27 ± 7 points; 45% met the El Escorial criteria for ALS defined at diagnosis and 58.8% met the Awaji criteria. There were 19 nerve conduction studies and 17 electromyograms, and an abductor digiti minimi–abductor pollicis brevis (ADM/APB) ratio < 0.6 was found in 63% (split hand). CONCLUSIONS: There is a significant delay in the diagnosis of motor neuron diseases in general and more particularly in VBS. Calculating the ADM/APB ratio and applying the Awaji criteria in the electrophysiology study can be a valuable aid to increase diagnostic certainty in this clinical entity

Electrophysiological subtypes and associated prognosis factors of Mexican adults diagnosed with Guillain-Barré syndrome, a single center experience.

BACKGROUND: The clinical characteristics of electrophysiological subtypes and prognostic factors of Mexican adults diagnosed with Guillain-Barré Syndrome (GBS) have not been described. MATERIALS AND METHODS: A single center, ambispective, cohort study was performed (2015-2019). GBS was defined following the Asbury and Cornblath criteria. Electrodiagnosis was made according to Hadden criteria. Clinical, biochemical and electrodiagnostic parameters were described, compared and analyzed using a multivariate model. Only patients who completed a 3-month follow-up were included. RESULTS: 137 GBS patients (92 males; mean age 46.6 ± 16.6).132 (96.3%) underwent an electrodiagnostic assessment.68 (51.5%) were classified as axonal GBS, with further classified into two groups: acute motor axonal neuropathy (AMAN) 45.4%, and acute motor and sensory axonal neuropathy (AMSAN) 8,6%. The following characteristics were lower in the AMAN group: Medical Research Counsel sumscore (MRC) 30.1 ± 16.3 vs 36.4 ± 14.4, unilateral facial palsy 10% vs 25.9% and albuminocytologic dissociation 41.3% vs. 71.7%.Multivariate analysis found AMAN as an independent predictor of an unfavorable outcome OR: 3.34 (p = 0.03) CONCLUSIONS: AMAN subtype is the most frequent presentation of GBS in Mexican adult patients and an independent predictor of inability to walk independently at 3 months after discharge.

Intravenous cyclophosphamide monthly pulses in refractory myasthenia gravis.

INTRODUCTION: Refractory myasthenia gravis (MG) is defined as a failure to respond adequately to conventional therapies, the inability to reduce immunosuppressive therapy without clinical relapse or the need for ongoing rescue therapy, severe adverse effects from immunosuppressive therapy (treatment intolerant) or frequent myasthenic crisis even on therapy. Cyclophosphamide (CYC) is a DNA alkylating agent that causes important interference in transcription processes and DNA replication, it has been used in refractory MG with controversial results. We aim to determine the efficacy of CYC in refractory MG in the Mexican population. METHODS: In an observational, longitudinal retrospective study, we identified eight refractory MG patients treated with 30-50 mg/kg monthly CYC for at least 6 months. The efficacy was assessed by Osserman scale considering significant improvement a ≥ 1 point reduction and Myasthenia Gravis Composite Scale. The relapse-free and remission-free period were also calculated using the Kaplan-Meier statistic. RESULTS: Clinical improvement was achieved in 75% of the patients. According to the Kaplan-Meier analysis, the median progression-free survival (PFS) was 9 (6.2-11.5) months and the median time to progression (TTP) was 4 (1-8) months. Response was independent of patient's characteristics, except for the MG age of onset (p = 0.0025). CONCLUSIONS: CYC was effective in all patients with refractory MG for a mean of 9 months, with worsening thereafter, which could be associated with low cumulative dose. The symptomatic improvement with CYC was noted within the 1st month. We conclude that CYC is effective as an induction to remission therapy, although our data suggest it is not effective as a long-term therapy.

Exquisite response to intravenous immunoglobulin in Susac syndrome during pregnancy.

INTRODUCTION: From its initial report on two female patients in 1979 by J.O. Susac, Susac syndrome (SuS) or SICRET (small infarctions of cochlear, retinal and encephalic tissue) has persisted as an elusive entity. To date the available evidence for its treatment is based on case reports and case series. The largest systematic review described only 304 reported cases since the 1970s. Here we presented the first reported case to our knowledge in Mexican population and the unusual presentation in a pregnant patient. CASE PRESENTATION: A 34-year-old Hispanic woman was brought to the ER in our hospital for apathy and behavioral changes. Upon arrival at the ER, her husband described a one-month history of behavioral changes with apathy, progressive abulia, visuospatial disorientation, and gait deterioration. The initial lab test shows no significance except by a positive qualitative hCG. An MRI was obtained and showed hyperintense periventricular white matter lesions in T2 and FLAIR sequences also involving bilateral basal ganglia and with predominant affection of the corpus callosum, in addition to infratentorial cerebellar lesions. After treatment with intravenous immunoglobulins a marked and prompt clinical and radiological improvement was observed. CONCLUSION: SuS is still an elusive disease. To date, no definitive score or clinical feature can predict the outcome of the disease. The presentation during pregnancy is also rare and therefore the optimal treatment and the prognosis is unknown. We hope that this article will serve as a foundation for future research.