Dados do Trabalho

Título

AGENESIS OF THE CORPUS CALLOSUM WITH PERIPHERAL NEUROPATHY: A PATHOGENIC VARIANT IN THE SLC12A6 GENE.

Apresentação do caso único

A 15-year-old female patient, born to consanguineous parents with no family history of neuromuscular diseases, presented with hypotonia and global developmental delay starting at 6 months. She developed diffuse muscle weakness including facial weakness, absence of deep tendon reflexes, muscular atrophy, joint contractures in hands and ankles, significant scoliosis, and intellectual disability. Brain MRI revealed agenesis of the corpus callosum, and NCS & EMG indicated an axonal sensorimotor polyneuropathy. A molecular panel identified a pathogenic homozygous variant in the SLC12A6 gene: c.1614del; (p.Phe538Leufs*18).

Discussão

Hereditary sensory and motor neuropathy also known as Charcot-Marie-Tooth disease (CMT), is the most common inherited peripheral nervous system disorder. It can follow autosomal dominant, autosomal recessive, or X-linked inheritance patterns. Biallelic variants in the SLC12A6 gene are linked to autosomal recessive hereditary motor and sensory neuropathy with corpus callosum agenesis. This rare condition involves both neurodevelopmental and neurodegenerative aspects, presenting clinically with corpus callosum dysgenesis and intellectual disability of varying severity. Neurodegeneratively, it manifests as severe, progressive sensorimotor neuropathy, leading to hypotonia, areflexia, and amyotrophy.
Diagnosis should be considered in individuals with specific clinical, electrophysiologic, and neuroimaging findings, especially with a suggestive family history. Confirmation is achieved through molecular genetic testing, identifying biallelic pathogenic or likely pathogenic variants in SLC12A6.

Comentários finais

Hereditary neuropathies encompass a group with increasing recognition of causative genes. Genotype-phenotype correlation can be complex, but systemic findings help narrow down candidate genes and aid in variant evaluation. Clinicians should be vigilant for central nervous system involvement, particularly in patients with cognitive impairment and epilepsy. Optimal care requires a multidisciplinary approach involving pediatricians, pediatric neurologists, orthopedists, physiotherapists, and occupational therapists.

Referências

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Palavras Chave

peripheral neuropathy; Neuromuscular diseases; Developmental delays