A natural history of paediatric RYR1-related congenital myopathies

Two major London paediatric neuromuscular centres carried out a retrospective study of 69 children with RYR1-related myopathy followed up between 1992 and 2019:

• 29 presented a dominantEn génétique, c’est la caractéristique d’un individu qui n’a besoin que d’un seul exemplaire d’un certain gène (allèle) pour s’exprimer. Cet exemplaire unique peut venir du père ou de la mère. form of myopathy linked to RYR1, 31 a recessive form, six a de novo dominant form and three a form of transmission as yet undefined;
• Onset ranged from birth to seven years;
• The median follow-up was 6.2 years, rising to 14.8 years;
• 15% of children over the age of two did not acquire walking ability, and 7% lost it during follow-up;
• 30% had scoliosis and 17% a stiff spine;
• 22% had respiratory problems and 12% required ventilatory assistance from a median age of seven years;
• the annual fall in vital capacity was -0.2% in recessive forms compared with -1.4% in dominant forms;
• Feeding difficulties were present in 30% of children, more than half of whom were receiving enteral nutrition.

Long-term Natural History of Pediatric Dominant and Recessive RYR1-Related Myopathy. Sarkozy A, Sa M, Ridout D et al. Neurology. 2023 Oct 10;101(15):e1495-e1508.