ABSTRACT
Defects in dystroglycan post-translational modification result in congenital muscular dystrophy with or without additional eye and brain involvement, are referred to as secondary dystroglycanopathies and have been associated with mutations in 11 different genes encoding glycosyltransferases or associated proteins. However, only one patient with a mutation in the dystroglycan encoding gene DAG1 itself has been described before. We here report a homozygous novel DAG1 missense mutation c.2006G>T predicted to result in the amino acid substitution p.Cys669Phe in the ß-subunit of dystroglycan in two Libyan siblings. The affected girls presented with a severe muscle-eye-brain disease-like phenotype with distinct additional findings of macrocephaly and extended bilateral multicystic white matter disease, overlapping with the cerebral findings in patients with megalencephalic leucoencephalopathy with subcortical cysts. This novel clinical phenotype observed in our patients further expands the clinical spectrum of dystroglycanopathies and suggests a role of DAG1 not only for dystroglycanopathies but also for some forms of more extensive and multicystic leucodystrophy.
Subject(s)
Dystroglycans/genetics , Leukoencephalopathies/genetics , Leukoencephalopathies/pathology , Walker-Warburg Syndrome/genetics , Walker-Warburg Syndrome/pathology , Amino Acid Substitution , Axons/pathology , Brain/pathology , Child, Preschool , Cysts/genetics , Female , Genetic Linkage , Homozygote , Humans , Leukoencephalopathies/diagnosis , Libya , Muscle, Skeletal/pathology , Mutation, Missense , Phenotype , Walker-Warburg Syndrome/diagnosisABSTRACT
BACKGROUND: The development and approval of disease modifying treatments have dramatically changed disease progression in patients with spinal muscular atrophy (SMA). Nusinersen was approved in Europe in 2017 for the treatment of SMA patients irrespective of age and disease severity. Most data on therapeutic efficacy are available for the infantile-onset SMA. For patients with SMA type 2 and type 3, there is still a lack of sufficient evidence and long-term experience for nusinersen treatment. Here, we report data from the SMArtCARE registry of non-ambulant children with SMA type 2 and typen 3 under nusinersen treatment with a follow-up period of up to 38 months. METHODS: SMArtCARE is a disease-specific registry with data on patients with SMA irrespective of age, treatment regime or disease severity. Data are collected during routine patient visits as real-world outcome data. This analysis included all non-ambulant patients with SMA type 2 or 3 below 18 years of age before initiation of treatment. Primary outcomes were changes in motor function evaluated with the Hammersmith Functional Motor Scale Expanded (HFMSE) and the Revised Upper Limb Module (RULM). RESULTS: Data from 256 non-ambulant, pediatric patients with SMA were included in the data analysis. Improvements in motor function were more prominent in upper limb: 32.4% of patients experienced clinically meaningful improvements in RULM and 24.6% in HFMSE. 8.6% of patients gained a new motor milestone, whereas no motor milestones were lost. Only 4.3% of patients showed a clinically meaningful worsening in HFMSE and 1.2% in RULM score. CONCLUSION: Our results demonstrate clinically meaningful improvements or stabilization of disease progression in non-ambulant, pediatric patients with SMA under nusinersen treatment. Changes were most evident in upper limb function and were observed continuously over the follow-up period. Our data confirm clinical trial data, while providing longer follow-up, an increased number of treated patients, and a wider range of age and disease severity.
Subject(s)
Muscular Atrophy, Spinal , Spinal Muscular Atrophies of Childhood , Child , Humans , Prospective Studies , Spinal Muscular Atrophies of Childhood/drug therapy , Registries , Disease Progression , Upper ExtremityABSTRACT
The natural history of patients with spinal muscular atrophy (SMA) has changed due to advances in standard care and development of targeted treatments. Nusinersen was the first drug approved for the treatment of all SMA patients. The transfer of clinical trial data into a real-life environment is challenging, especially regarding the advice of patients and families to what extent they can expect a benefit from the novel treatment. We report the results of a modified Delphi consensus process among child neurologists from Germany, Austria and Switzerland about the indication or continuation of nusinersen treatment in children with SMA type 1 based on different clinical case scenarios.