Development of respiratory care guidelines for Duchenne muscular dystrophy in the UK: key recommendations for clinical practice.

Significant inconsistencies in respiratory care provision for Duchenne muscular dystrophy (DMD) are reported across different specialist neuromuscular centres in the UK. The absence of robust clinical evidence and expert consensus is a barrier to the implementation of care recommendations in public healthcare systems as is the need to increase awareness of key aspects of care for those living with DMD. Here, we provide evidenced-based and/or consensus-based best practice for the respiratory care of children and adults living with DMD in the UK, both as part of routine care and in an emergency. METHODOLOGY: Initiated by an expert working group of UK-based respiratory physicians (including British Thoracic Society (BTS) representatives), neuromuscular clinicians, physiotherapist and patient representatives, draft guidelines were created based on published evidence, current practice and expert opinion. After wider consultation with UK respiratory teams and neuromuscular services, consensus was achieved on these best practice recommendations for respiratory care in DMD. RESULT: The resulting recommendations are presented in the form of a flow chart for assessment and monitoring, with additional guidance and a separate chart setting out key considerations for emergency management. The recommendations have been endorsed by the BTS. CONCLUSIONS: These guidelines provide practical, reasoned recommendations for all those managing day-to-day and acute respiratory care in children and adults with DMD. The hope is that this will support patients and healthcare professionals in accessing high standards of care across the UK.

Brain dopamine-serotonin vesicular transport disease presenting as a severe infantile hypotonic parkinsonian disorder.

Two male siblings from a consanguineous union presented in early infancy with marked truncal hypotonia, a general paucity of movement, extrapyramidal signs and cognitive delay. By mid-childhood they had made little developmental progress and remained severely hypotonic and bradykinetic. They developed epilepsy and had problems with autonomic dysfunction and oculogyric crises. They had a number of orthopaedic problems secondary to their hypotonia. Cerebrospinal fluid (CSF) neurotransmitters were initially normal, apart from mildly elevated 5-hydroxyindolacetic acid, and the children did not respond favourably to a trial of levodopa-carbidopa. The youngest died from respiratory complications at 10 years of age. Repeat CSF neurotransmitters in the older sibling at eight years of age showed slightly low homovanillic acid and 5-hydroxyindoleacetic acid levels. Whole-exome sequencing revealed a novel mutation homozygous in both children in the monoamine transporter gene SLC18A2 (p.Pro237His), resulting in brain dopamine-serotonin vesicular transport disease. This is the second family to be described with a mutation in this gene. Treatment with the dopamine agonist pramipexole in the surviving child resulted in mild improvements in alertness, communication, and eye movements. This case supports the identification of the causal mutation in the original case, expands the clinical phenotype of brain dopamine-serotonin vesicular transport disease and confirms that pramipexole treatment may lead to symptomatic improvement in affected individuals.

Effects of 12-Week Freestyle Libre 2.0 in Children with Type 1 Diabetes and Elevated HbA1c: A Multicenter Randomized Controlled Trial.

Objective: To investigate whether intermittently scanned continuous glucose monitoring (isCGM) reduced glycated hemoglobin (HbA1c) compared with capillary self-monitored capillary blood glucose (SMBG) in children with type 1 diabetes (T1D) and elevated glycemic control. Research Design and Methods: This multicenter 12-week 1:1 randomized, controlled, parallel-arm trial included 100 participants with established T1D aged 4-13 years (mean 10.9 ± 2.3 years) naive to isCGM and with elevated HbA1c 7.5%-12.2% [58-110 mmol/mol] [mean HbA1c was 9.05 (1.3)%] [75.4 (13.9) mmol/mol]. Participants were allocated to 12-week intervention (isCGM; FreeStyle Libre 2.0; Abbott Diabetes Care, Witney, United Kingdom) (n = 49) or control (SMBG; n = 51). The primary outcome was the difference in change of HbA1c from baseline to 12 weeks. Results: There was no evidence of a difference between groups for change in HbA1c at 12 weeks (0.23 [95% confidence interval; CI: -0.21 to 0.67], P = 0.3). However, glucose-monitoring frequency increased with isCGM +4.89/day (95% CI 2.97-6.81; P < 0.001). Percent time below range (TBR) <3.9 mmol/L (70-180 mg/dL) was reduced with isCGM -6.4% (10.6 to -4.2); P < 0.001. There were no differences in within group changes for Parent or Child scores of psychosocial outcomes at 12 weeks. Conclusions: For children aged 4-13 years with elevated Hba1c isCGM led to improvements in glucose testing frequency and reduced time below range. However, isCGM did not translate into reducing Hba1c or psychosocial outcomes compared to usual care over 12-weeks. The trial is registered within the Australian New Zealand Trial Registry on February 19, 2020 (ACTRN12620000190909p; ANZCTR.org.au) and the World Health Organization International Clinical Trials Registry Platform (Universal Trial Number U1111-1237-0090).

A comparison of FreeStyle Libre 2 to self-monitoring of blood glucose in children with type 1 diabetes and sub-optimal glycaemic control: a 12-week randomised controlled trial protocol.

PURPOSE: Frequent glucose monitoring is necessary for optimal glycaemic control. Second-generation intermittently scanned glucose monitoring (isCGM) systems inform users of out-of-target glucose levels and may reduce monitoring burden. We aim to compare FreeStyle Libre 2 (Abbott Diabetes Care, Witney, U.K.) to self-monitoring of blood glucose in children with type 1 diabetes and sub-optimal glycaemic control. METHODS: This open-label randomised controlled trial will enrol 100 children (4-13 years inclusive, diagnosis of type 1 diabetes ≥ 6 months, HbA1c 58-110 mmol/mol [7.5-12.2%]), from 5 New Zealand diabetes centres. Following 2 weeks of blinded sensor wear, children will be randomised 1:1 to control or intervention arms. The intervention (duration 12 weeks) includes second-generation isCGM (FreeStyle Libre 2) and education on using interstitial glucose data to manage diabetes. The control group will continue self-monitoring blood glucose. The primary outcome is the difference in glycaemic control (measured as HbA1c) between groups at 12 weeks. Pre-specified secondary outcomes include change in glucose monitoring frequency, glycaemic control metrics and psychosocial outcomes at 12 weeks as well as isCGM acceptability. DISCUSSION: This research will investigate the effectiveness of the second-generation isCGM to promote recommended glycaemic control. The results of this trial may have important implications for including this new technology in the management of children with type 1 diabetes. TRIAL REGISTRATION: This trial was prospectively registered with the Australian New Zealand Clinical Trials Registry on 19 February 2020 (ACTRN12620000190909p) and the World Health Organization International Clinical Trials Registry Platform (Universal Trial Number U1111-1237-0090).

Finding twinkle in the eyes of a 71-year-old lady: a case report and review of the genotypic and phenotypic spectrum of TWINKLE-related dominant disease.

Progressive external ophthalmoplegia (PEO) can be caused by a disorder characterized by multiple mitochondrial DNA (mtDNA) deletions due to mutations in the TWINKLE gene, encoding a mtDNA helicase. We describe a 71-year-old woman who had developed PEO at age 55 years. She had cataracts, diabetes, paresthesias, cognitive defects, memory problems, hearing loss, and sensory ataxia. She had muscle weakness with ragged red fibers on biopsy. MRI showed static white matter changes. A c.908G>A substitution (p.R303Q) in the TWINKLE gene was identified. Multiple mtDNA deletions were detected in muscle but not blood by a PCR-based method, but not by Southern blot analysis. MtDNA copy number was maintained in blood and muscle. A systematic literature search was used to identify the genotypic and phenotypic spectrum of dominant TWINKLE-related disease. Patients were adults with PEO and symptoms including myopathy, neuropathy, dysarthria or dysphagia, sensory ataxia, and parkinsonism. Diabetes, cataract, memory loss, hearing loss, and cardiac problems were infrequent. All reported mutations clustered between amino acids 303 and 508 with no mutations at the N-terminal half of the gene. The TWINKLE gene should be analyzed in adults with PEO even in the absence of mtDNA deletions in muscle on Southern blot analysis, and of a family history for PEO. The pathogenic mutations identified 5' beyond the linker region suggest a functional role for this part of the protein despite the absence of a primase function in humans. In our patient, the pathogenesis involved multiple mtDNA deletions without reduction in mtDNA copy number.

Effectiveness of current interventions in obese New Zealand children and adolescents.

AIMS: To determine the effectiveness of current interventions in New Zealand in obese children and adolescents accessing either a standard model of care (medical input alone or with the addition of dietitian and physical activity input), or one of the country's long-standing multi-disciplinary intervention programmes. METHODS: Data were recorded over approximately 2.1 years of intervention from 290 patients across four centres in New Zealand, who manage obese and overweight children and adolescents aged 3-16 years in paediatric clinics. RESULTS: There was a small but significant annual reduction in BMI SDS irrespective of the nature of intervention (-0.15 overall). There was no significant difference in BMI SDS between interventions. The extent of BMI SDS reduction decreased with increasing age at first outpatient attendance (p=0.0006). BMI SDS reduction was unaffected by ethnicity or gender. CONCLUSIONS: Mild reductions in BMI SDS are achievable in children being referred to and managed for obesity by a range of models. It is important that paediatricians are proactive in identifying and addressing obesity with families. Further research is required to evaluate multi-disciplinary intervention programmes, and how their effectiveness can be increased, given their recognised benefits in improving cardiovascular and metabolic profile, as well as BMI SDS.

Skeletal phenotype of mandibuloacral dysplasia associated with mutations in ZMPSTE24.

Mandibuloacral dysplasia (MAD) is a rare recessively inherited premature aging disease characterized by skeletal and metabolic anomalies. It is part of the spectrum of diseases called laminopathies and results from mutations in genes regulating the synthesis of the nuclear laminar protein, lamin A. Homozygous or compound heterozygous mutations in the LMNA gene, which encodes both the precursor protein prelamin A and lamin C, are the commonest cause of MAD type A. In a few cases of MAD type B, mutations have been identified in the ZMPSTE24 gene encoding a zinc metalloproteinase important in the post-translational modification of lamin A. Here we describe a new case of MAD resulting from compound heterozygote mutations in ZMPSTE24 (p.N256S/p.Y70fs). The patient had typical skeletal changes of MAD, but in addition a number of unusual skeletal features including neonatal tooth eruption, amorphous calcific deposits, submetaphyseal erosions, vertebral beaking, severe cortical osteoporosis and delayed fracture healing. Treatment with conventional doses of pamidronate improved estimated volumetric bone density in the spine but did not arrest cortical bone loss. We reviewed the literature on cases of MAD associated with proven LMNA and ZMPSTE24 mutations and found that the unusual features described above were all substantially more prevalent in patients with mutations in ZMPSTE24 than in those with LMNA mutations. We conclude that MAD associated with ZMPSTE24 mutations has a more severe phenotype than that associated with LMNA mutations--probably reflecting the greater retention of unprocessed farnesylated prelamin A in the nucleus, which is toxic to cells.