Dados do Trabalho

Título

Mutations in the gene MEGF10 causing a recessive congenital multiminicore myopathy

Apresentação do caso

Case Presentation:
A 5-year-old girl, born from a consanguineous couple, is referred to our service due to weakness and hypotonia. It was necessary hospitalisation, after birth, due to respiratory insufficiency and a severe motor delay was already evident in the first months of life. At 6 months she did not have head control and at 12 months she was not able to sit without support. She developed respiratory problems with apneas and hypercapnia, at 3 years of age, that was treated with bilevel positive airway pressure ventilation. Because of aspiration pneumonia gastrostomy was indicated at the age of 4. In her evaluation she had axial and proximal muscle weakness, facial weakness, scoliosis and hypernasal speech. Despite presenting with hypotonia and gait difficulties, she was able to walk independently and did not present cognitive impairment. At the neurological workup a muscle biopsy was performed and suggested a multiminicore myopathy. A genetic investigation resulted in a homozygous mutation of MEGF10 gene.

Discussão

Discussion:
Congenital myopathies result from a variety of genetic defects. They are classified into five main types: core myopathies, nemaline myopathies, centronuclear myopathies, congenital fiber-type disproportion, and myosin storage myopathies. Core myopathies such as central core disease and multiminicore disease are the most common forms of congenital myopathies. Despite their phenotypic diversity, patients demonstrate common symptoms including hypotonia, muscle weakness, dysmorphic features, and respiratory problems. There are several mutations in MEGF10 that have been reported to cause autosomal recessive congenital myopathy, areflexia, respiratory distress, muscle weakness, dysphagia with early or late-onset syndrome, minicore myopathy and limb girdle muscular dystrophy. Affected individuals frequently become ventilator dependent or die secondary to respiratory failure.

Comentários finais

Conclusion:
MEGF10 mutations should be considered in the differential diagnosis of individuals presenting with respiratory insufficiency and myopathy, particularly when accompanied by facial weakness, scoliosis or dysphagia. The phenotypic similarities with other congenital neuromuscular disorders may cause difficulties in reaching a definite diagnosis. Treatment with a multidisciplinary team is important and family counseling is essential since consanguineous unions play a role in recessive genetic mutations manifestations.

Referências (se houver)

Referencias:

1- Fujii K, Hirano M, Terayama A, Inada R, Saito Y, Nishino I, Nagai Y. Identification of a novel mutation and genotype-phenotype relationship in MEGF10 myopathy. Neuromuscul Disord. 2022 May;32(5):436-440. doi: 10.1016/j.nmd.2022.01.009. Epub 2022 Jan 31. PMID: 35370044.

2- AlMuhaizea M, Dabbagh O, AlQudairy H, AlHargan A, Alotaibi W, Sami R, AlOtaibi R, Ali MM, AlHindi H, Colak D, Kaya N. Phenotypic Variability of MEGF10 Variants Causing Congenital Myopathy: Report of Two Unrelated Patients from a Highly Consanguineous Population. Genes (Basel). 2021 Nov 10;12(11):1783. doi: 10.3390/genes12111783. PMID: 34828389; PMCID: PMC8620084.

3- Boyden SE, Mahoney LJ, Kawahara G, Myers JA, Mitsuhashi S, Estrella EA, Duncan AR, Dey F, DeChene ET, Blasko-Goehringer JM, Bönnemann CG, Darras BT, Mendell JR, Lidov HG, Nishino I, Beggs AH, Kunkel LM, Kang PB. Mutations in the satellite cell gene MEGF10 cause a recessive congenital myopathy with minicores. Neurogenetics. 2012 May;13(2):115-24. doi: 10.1007/s10048-012-0315-z. Epub 2012 Feb 28. PMID: 22371254; PMCID: PMC3332380.

4-Harris E, Marini-Bettolo C, Töpf A, Barresi R, Polvikoski T, Bailey G, Charlton R, Tellez J, MacArthur D, Guglieri M, Lochmüller H, Bushby K, Straub V. MEGF10 related myopathies: A new case with adult onset disease with prominent respiratory failure and review of reported phenotypes. Neuromuscul Disord. 2018 Jan;28(1):48-53. doi: 10.1016/j.nmd.2017.09.017. Epub 2017 Oct 12. PMID: 2912825

Declaração de conflito de interesses de TODOS os autores

Não