Pediatric myotonic dystrophy

Lagrue E, Dogan C, De Antonio M, Audic F, Bach N, Barnerias C, Bellance R, Cances C, Chabrol B, Cuisset JM, Desguerre I, Durigneux J, Espil C, Fradin M, Héron D, Isapof A, Jacquin-Piques A, Journel H, Laroche-Raynaud C, Laugel V, Magot A, Manel V, Mayer M, Péréon Y, Perrier-Boeswillald J, Peudenier S, Quijano-Roy S, Ragot-Mandry S, Richelme C, Rivier F, Sabouraud P, Sarret C, Testard H, Vanhulle C, Walther-Louvier U, Gherardi R, Hamroun D, Bassez G. A large multicenter study of pediatric myotonic dystrophy type 1 for evidence-based management. Neurology. 2019 Feb 19;92(8):e852-e865.

Abstract

OBJECTIVE:

To genotypically and phenotypically characterize a large pediatric myotonic dystrophy type 1 (DM1) cohort to provide a solid frame of data for future evidence-based health management.

METHODS:

Among the 2,697 patients with genetically confirmed DM1 included in the French DM-Scope registry, children were enrolled between January 2010 and February 2016 from 24 centers. Comprehensive cross-sectional analysis of most relevant qualitative and quantitative variables was performed.

RESULTS:

We studied 314 children (52% females, with 55% congenital, 31% infantile, 14% juvenile form). The age at inclusion was inversely correlated with the CTG repeat length. The paternal transmission rate was higher than expected, especially in the congenital form (13%). A continuum of highly prevalent neurodevelopmental alterations was observed, including cognitive slowing (83%), attention deficit (64%), written language (64%), and spoken language (63%) disorders. Five percent exhibited autism spectrum disorders. Overall, musculoskeletal impairment was mild. Despite low prevalence, cardiorespiratory impairment could be life-threatening, and frequently occurred early in the first decade (25.9%). Gastrointestinal symptoms (27%) and cataracts (7%) were more frequent than expected, while endocrine or metabolic disorders were scarce.

CONCLUSIONS:

The pedDM-Scope study details the main genotype and phenotype characteristics of the 3 DM1 pediatric subgroups. It highlights striking profiles that could be useful in health care management (including transition into adulthood) and health policy planning.