Abstract Limb-girdle muscular dystrophy (LGMD) is a group of myopathies that lead to progressive muscle weakness, predominantly involving the shoulder and pelvic girdles; it has a heterogeneous genetic etiology, with variation in the prevalence of subtypes according to the ethnic backgrounds and geographic origins of the populations. The aim of the present study was to analyze a series of patients with autosomal recessive LGMD (LGMD-R) to contribute to a better characterization of the disease and to find the relative proportion of the different subtypes in a Southern Brazil cohort. The sample population consisted of 36 patients with LGMD-R. A 9-gene targeted next-generation sequencing panel revealed variants in 23 patients with LGMD (64%), and it identified calpainopathy (LGMD-R1) in 26%, dysferlinopathy (LGMD-R2) in 26%, sarcoglycanopathies (LGMD-R3–R5) in 13%, telethoninopathy (LGMD-R7) in 18%, dystroglicanopathy (LGMD-R9) in 13%, and anoctaminopathy (LGMD-R12) in 4% of the patients. In these 23 patients with LGMD, there were 27 different disease-related variants in the ANO5, CAPN3, DYSF, FKRP, SGCA, SGCB, SGCG, and TCAP genes. There were different causal variants in different exons of these genes, except for the TCAP gene, for which all patients carried the p.Gln53* variant, and the FKRP gene, which showed recurrence of the p.Leu276Ile variant. We analyzed the phenotypic, genotypic and muscle immunohistochemical features of this Southern Brazilian cohort.

Resumo A distrofia muscular de cinturas (DMC) é um grupo de miopatias que leva à fraqueza muscular progressiva, e envolvendo predominante as cinturas escapular e pélvica. A DMCtem uma etiologia genética heterogênea, com variação na prevalência de subtipos de acordo com as origens étnicas e geográficas das populações. O objetivo deste estudo foi analisar uma série de pacientes com DMC do tipo autossômico recessivo (DMC-R) para contribuir para uma melhor caracterização da doença e encontrar a proporção relativa dos diferentes subtipos em uma coorte do Sul do Brasil. A população amostral foi composta por 36 pacientes com DMC-R. O painel de sequenciamento de nova geração com 9 genes revelou variantes em 23 pacientes com DMC (64%), e identificou calpainopatia (DMC-R1) em 26%, disferlinopatia (DMC-R2) em 26%, sarcoglicanopatias (DMC-R3–R5) em 13%, teletoninopatia (D-MCR7) em 18%, distroglicanopatia (D-MCR9) em 13%, e anoctaminopatia (DMC-R12) em 4% dos pacientes. Nesses 23 pacientes com DMC, havia 27 variantes diferentes nos genes ANO5, CAPN3, DYSF, FKRP, SGCA, SGCB, SGCG e TCAP. Foram encontradas diferentes variantes em diferentes éxons desses genes, com exceção do gene TCAP, para o qual todos os pacientes eram portadores da variante p.Gln53*, e do gene FKRP, que apresentou recorrência da variante p.Leu276Ile. As características fenotípicas, genotípicas e imuno-histoquímicas musculares desta coorte do Sul do Brasil foram analisadas.

ABSTRACT Background: Congenital myasthenic syndromes (CMS) have some phenotypic overlap with seronegative myasthenia gravis (SNMG). Objective: The aim of this single center study was to assess the minimum occurrence of CMS misdiagnosed as double SNMG in a Brazilian cohort. Methods: The genetic analysis of the most common mutations in CHRNE, RAPSN, and DOK7 genes was used as the main screening tool. Results: We performed genetic analysis in 22 patients with a previous diagnosis of ‘double’ SNMG. In this study, one CMS patient was confirmed due to the presence of compound heterozygous variants in the CHRNE gene (c.130insG/p.Cys210Phe). Conclusions: This study confirmed that CMS due to CHNRE mutations can be mistaken for SNMG. In addition, our study estimated the prevalence of misdiagnosed CMS to be 4.5% in ‘double’ SNMG patients of our center. Based on our findings, genetic screening could be helpful in the diagnostic workup of patients with ‘double’ SNMG in whom differential diagnosis is recommended.

RESUMO Antecedentes: As síndromes miastênicas congênitas (SMC) podem ter sobreposição fenotípica com a miastenia gravis soronegativa (MG-SN). Objetivo: Estabelecer a prevalência mínima de SMC diagnosticada inicialmente como MG duplo soronegativa em uma série de casos brasileiros. Métodos: A análise genética das mutações mais comuns nos genes CHRNE, RAPSN e DOK7 foi usada como o principal exame de triagem. Resultados: Vinte e dois pacientes com diagnóstico prévio de MG-SN foram geneticamente analisados, sendo que uma paciente foi confirmada com SMC devido a presença de variante em heterozigose composta no gene CHRNE (c.130insG/p.Cys210Phe). Conclusões: O presente estudo confirma que SMC devido mutação no gene CHNRE pode ser inicialmente diagnosticada como MG-SN. O estudo estimou como 4,5% a prevalência de diagnóstico de SMC entre nossos pacientes préviamente diagnosticados como MG-SN. Com base nesse estudo, a análise genética pode ser recomendada para investigação do diagnóstico diferencial em pacientes com MG-SN.

RESUMO Os autores apresentam uma revisão sobre aspectos da vida e obra do Professor Louis Ranvier 140 anos após a publicação de seu livro Leçons sur l’histologie du système nerveux publicado em 1878 e mostra a importância da descrição histológica nas fibras mielínicas dos nodos de Ranvier.

ABSTRACT This paper reviews aspects of the life and work of Professor Louis Ranvier 140 years after the publication of Leçons sur l’histologie du système nerveux, published in 1878, and shows the importance of the histological description of myelinated fibers of the nodes of Ranvier.

The aim of this study is to evaluate the clinical and laboratorial aspects, as well as the etiological profile and the evolution characteristics, of the diverse types of severe meningitis treated at a Pediatric Clinic of a public university hospital. From a descriptive and retrospective study, 312 children at the Pediatric Clinic of the Hospital de Clínicas of the Federal University of Paraná were evaluated between January 2003 and January 2007. All of them had a probable diagnosis of meningitis based on clinical signs, and on the cytological and biochemical alterations in the cerebrospinal fluid routine examination. Viral meningitis (VM) was present in 140 children (45%), 58 had bacterial meningitis (BM - 19%) and etiology was undetermined in 114 (36%). In MB, Neisseria meningitidis was the most frequent etiological agent (25 cases). Predominant clinical symptoms were fever, sickness and headache. The cerebrospinal fluid test showed a high number of polymorphonuclear leukocytes, high protein and low glucose level in MB; mononuclear cells were predominant in VM. Neurological complications were more frequent in BM, and convulsion the most common symptom (6/58 patients). Death happened to one case in VM and 3 in BM. Our conclusions were that the classical triad (headache, vomiting and fever) was the most common clinical manifestation, the cytological and biochemical abnormalities were typical, helping in the differentiation of MB from VM, although a good number of cases ended up with no etiological definition and, finally, immediate neurological complications and death were rare.

El objetivo de este trabajo fue evaluar los aspectos clínicos, análisis de laboratorio, el perfil etiológico y las características evolutivas de los distintos tipos de meningitis aguda atendidos en un Servicio de Pediatría de un Hospital Público Universitario. Fueron evaluados a partir de un estudio descriptivo y retrospectivo de niños atendidos en el Servicio de Pediatría del Hospital de Clínicas de la Universidad Federal del Paraná, durante el periodo entre enero 2003 a enero 2007, con el diagnóstico probable de meningitis basado en manifestaciones clínicas y en alteraciones citológicas y bioquímicas del LCR. Se diagnosticó meningitis viral (MV) en 140 niños (45%), meningitis bacteriana (MB) en 58 (19%) y en 114 la etiología fue indeterminada (36%). Entre las MB el agente etiológico más frecuente fue Neisseria meningitidis (25 casos). Lo datos clínicos predominantes fueron fiebre, vómitos y cefalea. En el LCR de la MB hubo predominio de polimorfonucleares, proteína elevada y glucosa baja. En la MV predominaron los mononucleares. Las complicaciones neurológicas fueron más frecuentes en la MB, siendo la convulsión el hallazgo más común (6/58 pacientes). El óbito ocurrió en un caso en la MV y tres en la MB. Se llegó a la conclusión de que la clásica tríada fue la manifestación clínica más común, las anormalidades citológicas y bioquímicas fueron típicas auxiliando en la diferenciación entre las MB y MV, aunque un gran número de casos haya quedado sin definición etiológica; las complicaciones neurológicas inmediatas y los óbitos han sido pocos frecuentes en esta muestra.