These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: KMT2B-related disorders: expansion of the phenotypic spectrum and long-term efficacy of deep brain stimulation.
    Author: Cif L, Demailly D, Lin JP, Barwick KE, Sa M, Abela L, Malhotra S, Chong WK, Steel D, Sanchis-Juan A, Ngoh A, Trump N, Meyer E, Vasques X, Rankin J, Allain MW, Applegate CD, Attaripour Isfahani S, Baleine J, Balint B, Bassetti JA, Baple EL, Bhatia KP, Blanchet C, Burglen L, Cambonie G, Seng EC, Bastaraud SC, Cyprien F, Coubes C, d'Hardemare V, Deciphering Developmental Disorders Study, Doja A, Dorison N, Doummar D, Dy-Hollins ME, Farrelly E, Fitzpatrick DR, Fearon C, Fieg EL, Fogel BL, Forman EB, Fox RG, Genomics England Research Consortium, Gahl WA, Galosi S, Gonzalez V, Graves TD, Gregory A, Hallett M, Hasegawa H, Hayflick SJ, Hamosh A, Hully M, Jansen S, Jeong SY, Krier JB, Krystal S, Kumar KR, Laurencin C, Lee H, Lesca G, François LL, Lynch T, Mahant N, Martinez-Agosto JA, Milesi C, Mills KA, Mondain M, Morales-Briceno H, NIHR BioResource, Ostergaard JR, Pal S, Pallais JC, Pavillard F, Perrigault PF, Petersen AK, Polo G, Poulen G, Rinne T, Roujeau T, Rogers C, Roubertie A, Sahagian M, Schaefer E, Selim L, Selway R, Sharma N, Signer R, Soldatos AG, Stevenson DA, Stewart F, Tchan M, Undiagnosed Diseases Network, Verma IC, de Vries BBA, Wilson JL, Wong DA, Zaitoun R, Zhen D, Znaczko A, Dale RC, de Gusmão CM, Friedman J, Fung VSC, King MD, Mohammad SS, Rohena L, Waugh JL, Toro C, Raymond FL, Topf M, Coubes P, Gorman KM, Kurian MA.
    Journal: Brain; 2020 Dec 05; 143(11):3242-3261. PubMed ID: 33150406.
    Abstract:
    Heterozygous mutations in KMT2B are associated with an early-onset, progressive and often complex dystonia (DYT28). Key characteristics of typical disease include focal motor features at disease presentation, evolving through a caudocranial pattern into generalized dystonia, with prominent oromandibular, laryngeal and cervical involvement. Although KMT2B-related disease is emerging as one of the most common causes of early-onset genetic dystonia, much remains to be understood about the full spectrum of the disease. We describe a cohort of 53 patients with KMT2B mutations, with detailed delineation of their clinical phenotype and molecular genetic features. We report new disease presentations, including atypical patterns of dystonia evolution and a subgroup of patients with a non-dystonic neurodevelopmental phenotype. In addition to the previously reported systemic features, our study has identified co-morbidities, including the risk of status dystonicus, intrauterine growth retardation, and endocrinopathies. Analysis of this study cohort (n = 53) in tandem with published cases (n = 80) revealed that patients with chromosomal deletions and protein truncating variants had a significantly higher burden of systemic disease (with earlier onset of dystonia) than those with missense variants. Eighteen individuals had detailed longitudinal data available after insertion of deep brain stimulation for medically refractory dystonia. Median age at deep brain stimulation was 11.5 years (range: 4.5-37.0 years). Follow-up after deep brain stimulation ranged from 0.25 to 22 years. Significant improvement of motor function and disability (as assessed by the Burke Fahn Marsden's Dystonia Rating Scales, BFMDRS-M and BFMDRS-D) was evident at 6 months, 1 year and last follow-up (motor, P = 0.001, P = 0.004, and P = 0.012; disability, P = 0.009, P = 0.002 and P = 0.012). At 1 year post-deep brain stimulation, >50% of subjects showed BFMDRS-M and BFMDRS-D improvements of >30%. In the long-term deep brain stimulation cohort (deep brain stimulation inserted for >5 years, n = 8), improvement of >30% was maintained in 5/8 and 3/8 subjects for the BFMDRS-M and BFMDRS-D, respectively. The greatest BFMDRS-M improvements were observed for trunk (53.2%) and cervical (50.5%) dystonia, with less clinical impact on laryngeal dystonia. Improvements in gait dystonia decreased from 20.9% at 1 year to 16.2% at last assessment; no patient maintained a fully independent gait. Reduction of BFMDRS-D was maintained for swallowing (52.9%). Five patients developed mild parkinsonism following deep brain stimulation. KMT2B-related disease comprises an expanding continuum from infancy to adulthood, with early evidence of genotype-phenotype correlations. Except for laryngeal dysphonia, deep brain stimulation provides a significant improvement in quality of life and function with sustained clinical benefit depending on symptoms distribution.
    [Abstract] [Full Text] [Related] [New Search]