Diagnostic reasoning in neurogenetics: a general approach

Abstract

Establishing the definitive diagnosis of a neurogenetic disease is usually a complex task. However, like any type of clinical diagnostic reasoning, an organized process of development and consideration of diagnostic hypotheses may guide neurologists and medical geneticists to solve this difficult task. The aim of the present review is to propose a general method for diagnostic reasoning in neurogenetics, with the definition of the main neurological syndrome and its associated topographical diagnosis, followed by the identification of major and secondary neurological syndromes, extraneurological findings, and inheritance pattern. We also discuss general rules and knowledge requirements of the ordering physician to request genetic testing and information on how to interpret genetic variants in a genetic report. By guiding the requests for genetic testing according to an organized model of diagnostic reasoning and with the availability of specific treatments, clinicians may find greater resoluteness and efficacy in the diagnostic investigation, shortening the struggle of patients for a definitive diagnosis.

Resumo

Estabelecer o diagnóstico definitivo de uma condição neurogenética geralmente é uma tarefa complexa; entretanto, semelhante a qualquer raciocínio diagnóstico clínico, um processo organizado de formulação e ponderação de hipóteses diagnósticas pode ajudar neurologistas e médicos geneticistas a resolverem essa difícil tarefa. O objetivo desta revisão é propor um método geral de raciocínio diagnóstico em neurogenética, com a definição da síndrome neurológica principal e seu diagnóstico topográfico associado, seguidos da identificação das síndromes neurológicas principais e secundárias, dos achados extraneurológicos, e do padrão de herança. Também discutimos as regras gerais e os requisitos de conhecimento do médico solicitante para o pedido de teste genético e informações sobre como interpretar variantes genéticas quando recebemos um laudo. Ao orientar a solicitação de exames genéticos de acordo com um modelo organizado de raciocínio diagnóstico e com a disponibilidade de tratamentos específicos, o clínico poderá encontrar maior resolutividade e eficiência na investigação diagnóstica, o que encurtará a odisseia do paciente para um diagnóstico definitivo.

Keywords

Neurology - Genetics, Medical - Diagnosis

Palavras-chave

Neurologia - Genética Médica - Diagnóstico

Authors' Contributions

HF: conceptualization, writing of the original draft; JLP: writing, review, and editing; JAS: conceptualization, writing of the original draft, and writing, review, and editing.

Publication History

Received: 22 June 2021

Accepted: 22 September 2021

Article published online:
09 November 2022

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