5 research outputs found
MPV17 mutations in juvenile- and adult-onset axonal sensorimotor polyneuropathy.
MPV17 encodes a putative channel-forming protein of the inner mitochondrial membrane and is involved in mitochondrial deoxynucleotide homeostasis. MPV17 mutations were first reported in patients with Navajo neurohepatopathy, an autosomal recessive mitochondrial DNA depletion syndrome, characterized by early-onset liver failure, failure to thrive as well as central and peripheral neurological involvement. Recently, two patients with juvenile-onset peripheral sensorimotor neuropathy associated with an MVP17 c.122G>A (p.Arg41Gln) variant have been reported. Here, we describe five additional patients from two unrelated families with sensorimotor axonal neuropathy without hepatocerebral affection caused by homozygous MPV17 variants. Patients of the first family carried the known c.122G>A variant and affected individuals of the second family had a novel c.376-9T>G near-splice variant, which was shown to result in an in-frame deletion of 11 amino acids. This report provides further evidence that MPV17 mutations should be considered in patients with pure, non-syndromic axonal neuropathy
The clinical and molecular landscape of congenital myasthenic syndromes in Austria: a nationwide study.
BACKGROUND: Congenital myasthenic syndromes (CMS) are a heterogeneous group of disorders caused by genetic defects resulting in impaired neuromuscular transmission. Although effective treatments are available, CMS is probably underdiagnosed, and systematic clinico-genetic investigations are warranted. METHODS: We used a nationwide approach to collect Austrian patients with genetically confirmed CMS. We provide a clinical and molecular characterization of this cohort and aimed to ascertain the current frequency of CMS in Austria. RESULTS: Twenty-eight cases with genetically confirmed CMS were identified, corresponding to an overall prevalence of 3.1 per million (95% CI 2.0-4.3) in Austria. The most frequent genetic etiology was CHRNE (n = 13), accounting for 46.4% of the cohort. Within this subgroup, the variant c.1327del, p.(Glu443Lysfs*64) was detected in nine individuals. Moreover, causative variants were found in DOK7 (n = 4), RAPSN (n = 3), COLQ (n = 2), GMPPB (n = 2), CHAT (n = 1), COL13A1 (n = 1), MUSK (n = 1) and AGRN (n = 1). Clinical onset within the first year of life was reported in one half of the patients. Across all subtypes, the most common symptoms were ptosis (85.7%), lower limb (67.9%), upper limb (60.7%) and facial weakness (60.7%). The majority of patients (96.4%) received specific treatment, including acetylcholinesterase inhibitors in 20, adrenergic agonists in 11 and 3,4-diaminopyridine in nine patients. CONCLUSIONS: Our study presents the first systematic characterization of individuals with CMS in Austria, providing prevalence estimates and genotype-phenotype correlations that may help to improve the diagnostic approach and patient management
The clinical and molecular landscape of congenital myasthenic syndromes in Austria: A nationwide study.
Background: Congenital myasthenic syndromes (CMS) are a heterogeneous group of disorders caused by genetic defects resulting in impaired neuromuscular transmission. Although effective treatments are available, CMS is probably underdiagnosed, and systematic clinico-genetic investigations are warranted. Methods: We used a nationwide approach to collect Austrian patients with genetically confirmed CMS. We provide a clinical and molecular characterization of this cohort and aimed to ascertain the current frequency of CMS in Austria. Results: Twenty-eight cases with genetically confirmed CMS were identified, corresponding to an overall prevalence of 3.1 per million (95% CI 2.0–4.3) in Austria. The most frequent genetic etiology was CHRNE (n = 13), accounting for 46.4% of the cohort. Within this subgroup, the variant c.1327del, p.(Glu443Lysfs*64) was detected in nine individuals. Moreover, causative variants were found in DOK7 (n = 4), RAPSN (n = 3), COLQ (n = 2), GMPPB (n = 2), CHAT (n = 1), COL13A1 (n = 1), MUSK (n = 1) and AGRN (n = 1). Clinical onset within the first year of life was reported in one half of the patients. Across all subtypes, the most common symptoms were ptosis (85.7%), lower limb (67.9%), upper limb (60.7%) and facial weakness (60.7%). The majority of patients (96.4%) received specific treatment, including acetylcholinesterase inhibitors in 20, adrenergic agonists in 11 and 3,4-diaminopyridine in nine patients. Conclusions: Our study presents the first systematic characterization of individuals with CMS in Austria, providing prevalence estimates and genotype–phenotype correlations that may help to improve the diagnostic approach and patient management
Supplementary Material for: Epidemiology of Amyotrophic Lateral Sclerosis and Effect of Riluzole on Disease Course
<p><b><i>Objectives:</i></b> To assess the epidemiology of ALS in Austria and to evaluate the long-term effect of riluzole treatment on survival. <b><i>Methods:</i></b>
Hospital discharge and riluzole prescription databases were used to
identify ALS cases from January 2008 to June 2012. Using the
capture-recapture method we evaluated the incidence and prevalence of
ALS and patients' survival in dependence of age, gender and riluzole
treatment. <b><i>Results:</i></b> The corrected incidence and prevalence
of ALS were 3.13/100,000 person-years (95% CI, 2.77 to 3.50) and
9.14/100,000 persons (95% CI, 8.53 to 9.79), respectively. Median
survival from diagnosis was 676 days (95% CI, 591 to 761). A younger age
at diagnosis was associated with a longer survival. Gender did not
appear to affect survival time. Riluzole therapy was associated with a
survival advantage only for the initial treatment period. The adjusted
hazard ratio of mortality for using riluzole increased continually over
time resulting in an apparent reversal of its beneficial effect after 6
months of therapy. <b><i>Conclusions:</i></b> We report incidence and
prevalence estimates that are on the upper end of the wide range
discussed in literature. Riluzole seems to exert a beneficial effect
only in the first 6 months of therapy.</p
Clinico-genetic spectrum of limb-girdle muscular weakness in Austria: A multi-centre cohort study.
BACKGROUND: Hereditary myopathies with limb-girdle muscular weakness (LGW) are a genetically heterogeneous group of disorders, in which molecular diagnosis remains challenging. Our aim was to present a detailed clinical and genetic characterisation of a large cohort of patients with LGW. METHODS: This nationwide cohort study included patients with LGW suspected to be associated with hereditary myopathies. Parameters associated with specific genetic aetiologies were evaluated, and we further assessed how they predicted the detection of causative variants by genetic analyses. RESULTS: Molecular diagnoses were identified in 62.0% (75/121) of the cohort, with a higher proportion of patients diagnosed by next-generation sequencing (NGS) than by single gene testing (77.3% vs. 22.7% of solved cases). Median time from onset to genetic diagnosis was 8.9 years (IQR 3.7-19.9) and 17.8 years (IQR 7.9-27.8) for single gene testing and NGS, respectively. The most common diagnoses were myopathies associated with variants in CAPN3 (n = 9), FKRP (n = 9), ANO5 (n = 8), DYSF (n = 8) and SGCA (n = 5), together accounting for 32.2% of the cohort. Younger age at disease onset (p = 0.043), >10x elevated CK activity levels (p = 0.024) and myopathic electromyography findings (p = 0.007) were significantly associated with the detection of causative variants. CONCLUSIONS: Our findings suggest an earlier use of NGS in patients with LGW to avoid long diagnostic delays. We further present parameters predictive of a molecular diagnosis that may help to select patients for genetic analyses, especially in centres with limited access to sequencing