RESUMO
Neurodegeneration with brain iron accumulation (NBIA) encompasses a clinically and genetically heterogeneous group of rare disorders. Here, we report clinical, neuroimaging and genetic studies in twenty three Brazilian NBIA patients. In thirteen subjects, deleterious variants were detected in known NBIA-causing genes (PANK2, PLA2G6, C9ORF12, WDR45 and FA2H), including previously unreported variants in PANK2 and PLA2G6. Two patients carried rare, likely pathogenic variants in genes not previously associated with NBIA: KMT2A c.11785A > C (p.Ile3929Leu), and TIMM8A c.127T > C (p.Cys43Arg), suggesting an expansion of their associated phenotypes to include NBIA. In eight patients the etiology remains unsolved, suggesting variants undetectable by the adopted methods, or the existence of additional NBIA-causing genes.
Assuntos
Neuroimagem , Humanos , Brasil , Feminino , Masculino , Adulto , Adolescente , Adulto Jovem , Criança , Pré-Escolar , Imageamento por Ressonância Magnética , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Encéfalo/patologia , Distrofias Neuroaxonais/genética , Distrofias Neuroaxonais/diagnóstico por imagem , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Ferro/metabolismo , Distúrbios do Metabolismo do Ferro/genética , Distúrbios do Metabolismo do Ferro/diagnóstico por imagem , Fosfolipases A2 do Grupo VIRESUMO
Neurodegeneration with brain iron accumulation (NBIA) is a complex group of hereditary progressive neurodegenerative diseases characterized by deposition of iron in the basal ganglia. Twelve genetic forms of this disorder have been identified in previous studies. Though they have different inheritance mechanisms all are usually associated with abnormal brain MRI findings. One of NBIA types is an X-linked disorder known as Beta-propeller Protein Associated Neurodegeneration (BPAN). Herein we describe the case of a 4-year-old girl with 2 episodes of febrile seizures, a brain MRI showing nonspecific hyperintense signal in the dentate nucleus area, and delays in language and communication development. Her diagnosis was made based on a genetic evaluation where exome sequencing revealed a mutation in the position chrX:48.933.022 region of the WDR45 gene. The literature describes different clinical presentations for BPAN, each with a different prognosis, suggesting a wide range of possible symptoms of BPAN, including mild cognitive delay and even epileptic encephalopathy (EE). (AU)
Assuntos
Humanos , Feminino , Pré-Escolar , Distrofias Neuroaxonais/diagnóstico , Distúrbios do Metabolismo do Ferro/diagnóstico , Convulsões Febris , Transtornos do Desenvolvimento da Linguagem , Proteínas de Transporte/genética , Distrofias Neuroaxonais/genética , Distúrbios do Metabolismo do Ferro/genéticaRESUMO
ABSTRACT Neurodegeneration with brain iron accumulation (NBIA) represents a heterogeneous and complex group of inherited neurodegenerative diseases, characterized by excessive iron accumulation, particularly in the basal ganglia. Common clinical features of NBIA include movement disorders, particularly parkinsonism and dystonia, cognitive dysfunction, pyramidal signs, and retinal abnormalities. The forms of NBIA described to date include pantothenase kinase-associated neurodegeneration (PKAN), phospholipase A2 associated neurodegeneration (PLAN), neuroferritinopathy, aceruloplasminemia, beta-propeller protein-associated neurodegeneration (BPAN), Kufor-Rakeb syndrome, mitochondrial membrane protein-associated neurodegeneration (MPAN), fatty acid hydroxylase-associated neurodegeneration (FAHN), coenzyme A synthase protein-associated neurodegeneration (CoPAN) and Woodhouse-Sakati syndrome. This review is a diagnostic approach for NBIA cases, from clinical features and brain imaging findings to the genetic etiology.
RESUMO A neurodegeneração com acúmulo cerebral de ferro (sigla em inglês NBIA) representa um grupo heterogêneo e complexo de doenças neurodegenerativas hereditárias, caracterizada pelo acúmulo cerebral de ferro, especialmente nos núcleos da base. O quadro clínico das NBIAs em geral inclui distúrbios do movimento, particularmente parkinsonismo e distonia, disfunção cognitiva, sinais piramidais e anormalidades da retina. As formas de NBIA descritas até o momento incluem neurodegeneração associada a pantothenase kinase (PKAN), neurodegeneração associada a phospholipase A2 (PLAN), neuroferritinopatia, aceruloplasminemia, neurodegeneração associada a beta-propeller protein (BPAN), síndrome de Kufor-Rakeb, neurodegeneração associada a mitochondrial membrane protein (MPAN), neurodegeneração associada a “fatty acid hydroxylase” (FAHN), neurodegeneração associada a coenzyme A synthase protein (CoPAN) e síndrome de Woodhouse-Sakati. Esta revisão é uma orientação para o diagnóstico das NBIAs, partindo das características clínicas e achados de neuroimagem, até a etiologia genética.
Assuntos
Humanos , Distrofias Neuroaxonais/genética , Distrofias Neuroaxonais/diagnóstico por imagem , Distúrbios do Metabolismo do Ferro/genética , Distúrbios do Metabolismo do Ferro/diagnóstico por imagem , Neuroimagem/métodos , Mutação , Arritmias Cardíacas/genética , Arritmias Cardíacas/diagnóstico por imagem , Doenças dos Gânglios da Base/genética , Doenças dos Gânglios da Base/diagnóstico por imagem , Ceruloplasmina/deficiência , Ceruloplasmina/genética , Coenzima A Ligases/genética , Transtornos Heredodegenerativos do Sistema Nervoso/genética , Transtornos Heredodegenerativos do Sistema Nervoso/diagnóstico por imagem , Diabetes Mellitus/genética , Diabetes Mellitus/diagnóstico por imagem , Alopecia/genética , Alopecia/diagnóstico por imagem , Hipogonadismo/genética , Hipogonadismo/diagnóstico por imagemRESUMO
ABSTRACT Pantothenate kinase-associated neurodegeneration (PKAN) is an autosomal recessive disorder caused by mutation in the PANK2 gene. It is characterized by abnormal brain iron accumulation, mainly in the globus pallidus. PKAN is included in a group of disorders known as neurodegeneration with brain iron accumulation (NBIA). We report a case of atypical PKAN with its most characteristic presentation, exhibiting marked psychiatric symptoms, speech disorder and focal dystonia. Brain MRI has great diagnostic importance in this group of disorders and, in this case, disclosed the eye-of-the-tiger sign. Genetic testing confirmed the diagnosis.
RESUMO Neurodegeneração associada à pantotenato-quinase (PKAN) é uma entidade autossômica recessiva causada pela mutação do gene PANK2. Caracteriza-se por depósito cerebral anormal de ferro, particularmente nos globos pálidos. PKAN faz parte de um grupo de desordens conhecidas como neurodegeneração com acúmulo cerebral de ferro (NBIA). Relatamos um caso de PKAN atípica com sua apresentação mais característica, sendo evidentes sintomas psiquiátricos marcados, distúrbio da fala e distonia focal. A ressonância magnética de crânio possui grande importância diagnóstica neste grupo de desordens, e neste caso, demonstrou o sinal do olho de tigre. O teste genético confirmou o diagnóstico.
Assuntos
Humanos , Distrofias Neuroaxonais , Neurodegeneração Associada a Pantotenato-QuinaseRESUMO
Pantothenate kinase-associated neurodegeneration (PKAN) is an autosomal recessive disorder caused by mutation in the PANK2 gene. It is characterized by abnormal brain iron accumulation, mainly in the globus pallidus. PKAN is included in a group of disorders known as neurodegeneration with brain iron accumulation (NBIA). We report a case of atypical PKAN with its most characteristic presentation, exhibiting marked psychiatric symptoms, speech disorder and focal dystonia. Brain MRI has great diagnostic importance in this group of disorders and, in this case, disclosed the eye-of-the-tiger sign. Genetic testing confirmed the diagnosis.
Neurodegeneração associada à pantotenato-quinase (PKAN) é uma entidade autossômica recessiva causada pela mutação do gene PANK2. Caracteriza-se por depósito cerebral anormal de ferro, particularmente nos globos pálidos. PKAN faz parte de um grupo de desordens conhecidas como neurodegeneração com acúmulo cerebral de ferro (NBIA). Relatamos um caso de PKAN atípica com sua apresentação mais característica, sendo evidentes sintomas psiquiátricos marcados, distúrbio da fala e distonia focal. A ressonância magnética de crânio possui grande importância diagnóstica neste grupo de desordens, e neste caso, demonstrou o sinal do olho de tigre. O teste genético confirmou o diagnóstico.
RESUMO
Discovery of genetic abnormalities associated with neurodegeneration with brain iron accumulation (NBIA) has led to use of a genetic-based NBIA classification schema. Most NBIA subtypes demonstrate characteristic imaging abnormalities. While clinical diagnosis of NBIA is difficult, analysis of both clinical findings and characteristic imaging abnormalities allows accurate diagnosis of most of the NBIA subtypes. This article reviews recent updates in the genetic, clinical, and imaging findings of NBIA subtypes and provides a practical step-by-step clinicoradiological algorithm toward clinical diagnosis of different NBIA subtypes.