Clinical and Genetic Aspects of Juvenile Amyotrophic Lateral Sclerosis: A Promising Era Emerges.

Juvenile Amyotrophic Lateral Sclerosis is a genetically heterogeneous neurodegenerative disorder, which is frequently misdiagnosed due to low clinical suspicion and little knowledge about disease characteristics. More than 20 different genetic loci have been associated with both sporadic and familial juvenile Amyotrophic Lateral Sclerosis. Currently, almost 40% of cases have an identifiable monogenic basis; type 6, associated with FUS gene variants, is the most prevalent globally. Despite several upper motor neuron-dominant forms being generally associated with long-standing motor symptoms and slowly progressive course, certain subtypes with lower motor neuron-dominant features and early bulbar compromise lead to rapidly progressive motor handicap. For some monogenic forms, there is a well-established genotypic-phenotypic correlation. There are no specific biochemical and neuroimaging biomarkers for the diagnosis of juvenile Amyotrophic Lateral Sclerosis. There are several inherited neurodegenerative and neurometabolic disorders which can lead to the signs of motor neuron impairment. This review emphasizes the importance of high clinical suspicion, assessment, and proper diagnostic work-up for juvenile Amyotrophic Lateral Sclerosis.

Myasthenia gravis in the complex scenario of LRBA-related immune dysregulation / Miastenia gravis no cenário clínico complexo das imunodesregulações relacionadas ao gene LRBA

Autoimmune diseases have been progressively recognized as a potential complication of primary immunodeficiency, especially for some genetic subtypes of common variable immunodeficiency. Although often associated with other autoimmune disorders, autoimmune myasthenia gravis is occasionally identified as a neuromuscular complication of primary immunodeficiency. We report the case of a Brazilian woman with common variable immunodeficiency-8 due to an LRBA variant, in which myasthenia gravis was identified in association with anti-acetylcholine receptor antibody. Marked clinical improvement occurred after intravenous immunoglobulin therapy.

Doenças autoimunes foram progressivamente reconhecidas como complicações potenciais das imunodeficiências primárias, especialmente para alguns subtipos genéticos das imunodeficiências comuns variáveis. Embora se associe comumente a outras doenças autoimunes, a Miastenia gravis autoimune adquirida foi raramente associada como complicação neuromuscular de imunodeficiências primárias. É descrito neste artigo o caso de paciente brasileira do sexo feminino com diagnóstico de Imunodeficiência Comum Variável tipo 8 por variante no gene LRBA, na qual foi identificada Miastenia gravis em associação a anticorpos antirreceptor de acetilcolina. Ela evoluiu com marcante melhora clínica após a introdução de terapêutica com imunoglobulina endovenosa.

Clinical and Genetic Aspects of Childhood-Onset Demyelinating Charcot-Marie-Tooth's Disease in Brazil.

Charcot-Marie-Tooth's disease (CMT) represents the most common inherited neuropathy. Most patients are diagnosed during late stages of disease course during adulthood. We performed a review of clinical, neurophysiological, and genetic diagnoses of 32 patients with genetically defined childhood-onset demyelinating CMT under clinical follow-up in a Brazilian Center for Neuromuscular Diseases from January 2015 to December 2019. The current mean age was 33.1 ± 18.3 years (ranging from 7 to 71 years) and mean age at defined genetic diagnosis was 36.1 ± 18.3 years. The mean age at onset was 6.1 ± 4.4 years. The most common initial complaint was bilateral pes cavus. The genetic basis included PMP22 duplication (CMT1A) ( n = 18), GJB1 (CMTX1) ( n = 5), MPZ (CMT1B) ( n = 3), FIG4 (CMT4J) ( n = 3), SH3TC2 (CMT4C) ( n = 1), PLEKHG5 (CMTRIC) ( n = 1), and PRX (CMT4F) ( n = 1). Almost all patients ( n = 31) presented with moderate or severe compromise in the CMT neuropathy score 2 with the highest values observed in CMT1B. Medical history disclosed obstructive sleep apnea ( n = 5), aseptic meningitis ( n = 1/ MPZ ), akinetic-rigid parkinsonism ( n = 1/ FIG4 ), and overlapping chronic inflammatory demyelinating polyneuropathy ( n = 1/ MPZ ). Motor conduction block was detected in three individuals ( PMP22 , FIG4 , MPZ ). Acute denervation occurred in seven patients. Nonuniform demyelinating patterns were seen in four individuals (two CMT1A, one CMT1B, and one CMTX1). Abnormal cerebral white matter findings were detected in CMT1A and CMTX1, while hypertrophic roots were seen in CMT1A, CMT1B, and CMTX1. Our study emphasizes a relative oligogenic basis in childhood-onset demyelinating CMT and atypical findings may be observed especially in MPZ , PMP22 , and GJB1 gene variants.

The expanding clinical and genetic spectrum of alsin-related disorders: the first cohort of Brazilian patients.

There are three types of autosomal recessive disorders involving pathogenic variants in the ALS2 gene (OMIM*606352), infantile ascending hereditary spastic paraplegia (IAHSP), juvenile primary lateral sclerosis (JPLS) and juvenile amyotrophic lateral sclerosis (JALS), which are rare and related to retrograde degeneration of motor neurons. ALS2 pathogenic variants are distributed widely across the entire coding sequence and mostly result in a loss of protein function. Rarely, patients with JALS have been reported with lower motor neuron involvement. Here, we report the first Brazilian cohort (six patients) of JPLS with novel ALS2 pathogenic variants, and we propose an expanding clinical and genetic spectrum of alsin-related disorders. A review of the literature in PubMed from 2001 to September 2020 allowed us to identify 26 publications about the three different phenotypes caused by ALS2 variants (only case reports or families), encompassing 35 nonrelated families. We compiled data (sex, age, age at onset, first symptoms, atypical clinical features, molecular data, and clinical evolution (improvement or death)) from these studies and analyzed them in a general context on the basis of demographic features.

Immunosuppressors and immunomodulators in Neurology - Part I: a guide for management of patients underimmunotherapy.

For patients with autoimmune diseases, the risks and benefits of immunosuppressive or immunomodulatory treatment are a matter of continual concern. Knowledge of the follow-up routine for each drug is crucial, in order to attain better outcomes and avoid new disease activity or occurrence of adverse effects. To achieve control of autoimmune diseases, immunosuppressive and immunomodulatory drugs act on different pathways of the immune response. Knowledge of the mechanisms of action of these drugs and their recommended doses, adverse reactions and risks of infection and malignancy is essential for safe treatment. Each drug has a specific safety profile, and management should be adapted for different circumstances during the treatment. Primary prophylaxis for opportunistic infections and vaccination are indispensable steps during the treatment plan, given that these prevent potential severe infectious complications. General neurologists frequently prescribe immunosuppressive and immunomodulatory drugs, and awareness of the characteristics of each drug is crucial for treatment success. Implementation of a routine before, during and after use of these drugs avoids treatment-related complications and enables superior disease control.

Immunosuppressors and immunomodulators in Neurology - Part I: a guide for management of patients underimmunotherapy / Imunossupressores e imunomoduladores em Neurologia - Parte I: um guia para o manejo de pacientes em imunoterapia

ABSTRACT For patients with autoimmune diseases, the risks and benefits of immunosuppressive or immunomodulatory treatment are a matter of continual concern. Knowledge of the follow-up routine for each drug is crucial, in order to attain better outcomes and avoid new disease activity or occurrence of adverse effects. To achieve control of autoimmune diseases, immunosuppressive and immunomodulatory drugs act on different pathways of the immune response. Knowledge of the mechanisms of action of these drugs and their recommended doses, adverse reactions and risks of infection and malignancy is essential for safe treatment. Each drug has a specific safety profile, and management should be adapted for different circumstances during the treatment. Primary prophylaxis for opportunistic infections and vaccination are indispensable steps during the treatment plan, given that these prevent potential severe infectious complications. General neurologists frequently prescribe immunosuppressive and immunomodulatory drugs, and awareness of the characteristics of each drug is crucial for treatment success. Implementation of a routine before, during and after use of these drugs avoids treatment-related complications and enables superior disease control.

RESUMO Pacientes com doenças autoimunes exigem uma constante preocupação com os riscos e benefícios do tratamento imunossupressor ou imunomodulador. O conhecimento das rotinas no uso de cada uma dessas drogas é fundamental para o bom desfecho clínico, evitando a piora da doença ou efeitos colaterais. As drogas imunossupressoras e imunomoduladoras agem em diferentes pontos da resposta imunológica a fim de controlar a doença para qual são indicadas. O conhecimento do mecanismo de ação, principais posologias, efeitos adversos e os riscos de infecções e neoplasias relacionadas ao uso dessas medicações são fundamentais para um tratamento seguro. Cada uma delas apresenta um perfil específico de complicações e o manejo deve ser individualizado em diferentes cenários ao longo do seguimento do paciente. O uso de medicações para profilaxia primária de infecções e a vacinação são pontos essenciais no planejamento do tratamento, prevenindo potenciais complicações infecciosas ao longo do acompanhamento. O uso de imunossupressores e imunomoduladores é uma frequente realidade no dia-a-dia do neurologista, e o conhecimento das características de cada droga é crucial para o sucesso do tratamento. A realização de uma rotina antes, durante e depois do uso dessas medicações evita complicações relacionadas com o tratamento e alcança um melhor controle da doença.

Adult-onset non-5q proximal spinal muscular atrophy: a comprehensive review.

BACKGROUND: Adult-onset spinal muscular atrophy (SMA) represents an expanding group of inherited neurodegenerative disorders in clinical practice. OBJECTIVE: This review aims to synthesize the main clinical, genetic, radiological, biochemical, and neurophysiological aspects related to the classical and recently described forms of proximal SMA. METHODS: The authors performed a non-systematic critical review summarizing adult-onset proximal SMA presentations. RESULTS: Previously limited to cases of SMN1-related SMA type 4 (adult form), this group has now more than 15 different clinical conditions that have in common the symmetrical and progressive compromise of lower motor neurons starting in adulthood or elderly stage. New clinical and genetic subtypes of adult-onset proximal SMA have been recognized and are currently target of wide neuroradiological, pathological, and genetic studies. CONCLUSIONS: This new complex group of rare disorders typically present with lower motor neuron disease in association with other neurological or systemic signs of impairment, which are relatively specific and typical for each genetic subtype.

Adult-onset non-5q proximal spinal muscular atrophy: a comprehensive review / Atrofia muscular espinhal não-5q proximal de início no adulto: uma revisão abrangente

Abstract Background: Adult-onset spinal muscular atrophy (SMA) represents an expanding group of inherited neurodegenerative disorders in clinical practice. Objective: This review aims to synthesize the main clinical, genetic, radiological, biochemical, and neurophysiological aspects related to the classical and recently described forms of proximal SMA. Methods: The authors performed a non-systematic critical review summarizing adult-onset proximal SMA presentations. Results: Previously limited to cases of SMN1-related SMA type 4 (adult form), this group has now more than 15 different clinical conditions that have in common the symmetrical and progressive compromise of lower motor neurons starting in adulthood or elderly stage. New clinical and genetic subtypes of adult-onset proximal SMA have been recognized and are currently target of wide neuroradiological, pathological, and genetic studies. Conclusions: This new complex group of rare disorders typically present with lower motor neuron disease in association with other neurological or systemic signs of impairment, which are relatively specific and typical for each genetic subtype.

RESUMO Antecedentes: Atrofia muscular espinhal (AME) de início no adulto representa um grupo de doenças neurodegenerativas hereditárias em expansão na prática clínica. Objetivo: Este artigo de revisão sintetiza os principais aspectos clínicos, genéticos, radiológicos, bioquímicos e neurofisiológicos relacionados às formas clássicas e recentemente descritas de AME proximal do adulto. Métodos: Os autores realizaram uma revisão crítica não sistemática descrevendo as principais apresentações de AME proximal de início no adulto. Resultados: Previamente restrito às apresentações de AME tipo 4 associada ao gene SMN1, este grupo atualmente envolve mais de 15 diferentes condições clínicas que compartilham entre si a presença de comprometimento progressivo e simétrico do neurônio motor inferior se iniciando no adulto ou no idoso. Novos subtipos clínicos e genéticos de AME proximal de início no adulto foram reconhecidas e são alvos atuais de estudos direcionados a aspectos neurorradiológicos, patológicos e genéticos. Conclusões: Este novo grupo complexo de doenças raras tipicamente se apresenta com doença do neurônio motor inferior em associação com outros sinais de comprometimento neurológico ou sistêmico, os quais apresentam padrões relativamente específicos para cada subtipo genético.

Acute hepatic porphyrias for the neurologist: current concepts and perspectives.

BACKGROUND: Acute hepatic porphyrias represent an expanding group of complex inherited metabolic disorders due to inborn errors of metabolism involving heme biosynthesis. OBJECTIVE: We aimed to review the main clinical and therapeutic aspects associated with acute hepatic porphyrias. METHODS: The authors provided a wide non-systematic review of current concepts and recently acquired knowledge about acute hepatic porphyrias. RESULTS: Acute neurovisceral attacks are the most common and life-threatening presentation of this group and are often considered the main clinical manifestation by clinicians during differential diagnosis and the start of proper diagnostic work-up for acute porphyrias. However, atypical presentations with central nervous system involvement, neuropsychiatric disturbances, and some subtypes with photosensitivity usually make the definite diagnosis difficult and late. Early therapeutic interventions are essential during emergency treatment and intercritical periods to avoid recurrent severe presentations. The availability of new disease-modifying therapeutic proposals based on small interfering RNA (siRNA)-based therapies, complementary to the classic intravenous glucose infusion and hemin-based treatments, emphasizes the importance of early diagnosis and genetic counseling of patients. CONCLUSIONS: This review article highlights the main biochemical, pathophysiological, clinical, and therapeutic aspects of acute hepatic porphyrias in clinical practice.