IMPORTANCE Ataxia with oculomotor apraxia type 1 (AOA1) is an autosomal recessive cerebellar ataxia due to mutations in the aprataxin gene (APTX) that is characterized by early-onset cerebellar ataxia, oculomotor apraxia, axonal motor neuropathy, and eventual decrease of albumin serum levels. OBJECTIVES To improve the clinical, biomarker, and molecular delineation of AOA1 and provide genotype-phenotype correlations. DESIGN, SETTING, AND PARTICIPANTS This retrospective analysis included the clinical, biological (especially regarding biomarkers of the disease), electrophysiologic, imaging, and molecular data of all patients consecutively diagnosed with AOA1 in a single genetics laboratory from

BackgroundAutosomal recessive cerebellar ataxias (ARCA) are a complex group of neurodegenerative disorders with great genetic and phenotypic heterogeneity, over 30 genes/loci have been associated with more than 20 different clinical forms of ARCA. Genetic heterogeneity combined with highly variable clinical expression of the cerebellar symptoms and overlapping features complicate furthermore the etiological diagnosis of ARCA. The determination of the most frequent mutations and corresponding ataxias, as well as particular features specific to a population, are mandatory to facilitate and speed up the diagnosis process, especially when an appropriate treatment is available.MethodsWe explored 166 patients (115 families) refered to the neurology units of Algiers central hospitals (Algeria) with a cerebellar ataxia phenotype segregating as an autosomal recessive pattern of inheritance. Genomic DNA was extracted from peripheral blood samples and mutational screening was performed by PCR and direct sequencing or by targeted genomic capture and massive parallel sequencing of 57 genes associated with inherited cerebellar ataxia phenotypes.ResultsIn this work we report the clinical and molecular results obtained on a large cohort of Algerian patients (110 patients/76 families) with genetically determined autosomal recessive ataxia, representing 9 different types of ARCA and 23 different mutations, including 6 novel ones. The five most common ARCA in this cohort were Friedreich ataxia, ataxia with isolated vitamin E deficiency, ataxia with oculomotor apraxia type 2, autosomal recessive spastic ataxia of Charlevoix-Saguenay and ataxia with oculomotor apraxia type 1.ConclusionWe report here a large cohort of patients with genetically determined autosomal recessive ataxia and the first study of the genetic context of ARCA in Algeria. This study showed that in Algerian patients, the two most common types of ataxia (Friedreich ataxia and ataxia with isolated vitamin E deficiency) coexist with forms that may be less common or underdiagnosed. To refine the genotype/phenotype correlation in rare and heteregeneous diseases as autosomal recessive ataxias, more extensive epidemiological investigations and reports are necessary as well as more accurate and detailed clinical characterizations. The use of standardized clinical and molecular protocols would thus enable a better knowledge of the different forms of ARCA.

ObjectiveWe describe and compare the sociodemographic and clinical features, treatments, and prognoses and survival times of patients with amyotrophic lateral sclerosis (ALS) in Africa.MethodologyWe conducted a multicentre, hospital-based cohort study in Africa. Patients with ALS diagnosed in the neurology departments of participating hospitals from 2005 to 2017 were included. Subgroup analysis was performed by subcontinent. Survival analyses were conducted using the Cox proportional hazards model.ResultsNine centres from eight African countries participated. A total of 185 patients with ALS were included: 114 from Northern Africa, 41 from Western Africa and 30 from Southern Africa. A male predominance (male to female ratio 2.9) was evident. The median age at onset was 53.0 years (IQR 44.5–64.0 years). The onset was bulbar in 22.7%. Only 47 patients (26.3%) received riluzole, mainly in Northern and Western Africa. The median survival from the time of diagnosis was 14.0 months (95% CI 10.7 to 17.2 months). The median survival was longer in Northern Africa (19.0 months, 95% CI 10.8 to 27.2 months) than in Western (4.0 months, 95% CI 0.8 to 7.1 months) and Southern (11.0 months, 95% CI 5.6 to 16.4 months) Africa (Breslow test, p<0.0001). Both subcontinental location and riluzole treatment independently affected survival.ConclusionMore African patients with ALS were male and younger and exhibited a lower proportion of bulbar onset compared with patients with ALS from Western nations. Survival was consistent with that in Western registers but far shorter than what would be expected for young patients with ALS. The research improves our understanding of the disease in Africa.

No abstract