Dados do Trabalho

Título

SEVERE CASE OF MYOTONIC DYSTROPHY TYPE 1 ASSOCIATED WITH SYRINGOMYELIA

Apresentação do caso

A 11-year-old brazilian boy, without family history of neurological disease, presented at 1 year and 6 months of age with pain crisis after a reconstructive surgery to correct hypospadias, and, during the postoperative period, evolved with lack of sphincter control and difficulty walking. During this period, was diagnosed with syringomyelia and, at 4-year-old, underwent surgical treatment (Filum System® method), with total improvement for 4 months. Soon after, presented with metabolic, endocrine, respiratory, cardiac, locomotor and neurocognitive deterioration, requiring a transdisciplinary approach. The final diagnosis of DM1 was confirmed by molecular genetic testing of DM protein kinase (DMPK), which showed a CTG triplet repeat expansion of 97. Although the diagnosis was established, the disease management remains a challenge, due to the multiple systems affected and lack of established therapy for DM1.

Discussão

DM1 is a genetic neuromuscular disorder, inherited in an autosomal dominant fashion of variable penetrance, caused by unstable repeat expansions of the CTG triplet in the DMPK gene (locus 19q13.3). The clinical manifestations are extremely miscellaneous, patients with childhood-onset DM1 are usually associated with cognitive and behavioral symptoms, differently from what happened in the present case. Cardiorespiratory problems, although rare, are potentially life threatening to these patients. Due to the low occurrence of DM1 associated with syringomyelia, it is not possible to associate both diseases yet. Disagreements in the literature about the management of patients and about the association between the size of the CTG codon expansion and the severity of symptoms are extremely prevalent.

Comentários finais

This is a severe case of childhood-onset DM1 associated with syringomyelia, in which the patient presented deterioration of multiple systems, requiring a transdisciplinary approach. Due to the miscellaneous presentations of DM1, disagreements are prevalent in the literature on the management of patients, so there is great need to deepen knowledge about this disease in order to improve the clinical outcome of patients.

Referências (se houver)

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Declaração de conflito de interesses de TODOS os autores

Sem conflito de interesse