Aspects electroneuromyographiques des traumatismes du plexus brachial

Introduction: L’électroneuromyogramme (ENMG) garde une place cruciale dans l’exploration du plexus brachial. L’objectif de cette étude était d’étudier les caractéristiques électroneuromyographiques des atteintes plexiques brachiales post-traumatiques et de déterminer les facteurs associés à la topographie et à la sévérité des lésions. Patients et méthodes: Une étude rétrospective a été réalisée dans le service de Neurologie du CHU RAZI incluant les patients adressés à l’unité d’électroneurophysiologie pour une atteinte traumatique du plexus brachial durant la période allant de janvier 2003 à juin 2018. Les données démographiques, cliniques et les résultats de l’ENMG ont été recueillis et analysés. La sévérité de la lésion a été évaluée selon la version modifiée de l’échelle de Dumitru et Wilbourn. Résultats: Nous avons colligé 36 plexopathies brachiales post traumatiques chez 35 patients (H/F = 30/5, âge moyen = 39,3 ans). L’ENMG a été réalisé 3 semaines après le traumatisme chez 91,3% des patients. Il a montré une conduction nerveuse altérée (97,2 %), un tracé neurogène (91,7 %) et des signes de dénervation (55,6 %). Le niveau lésionnel concernait les troncs primaires (66,7 %) et les troncs secondaires (33,3 %). Il était sans lien significatif avec la cause (p>0,05). La lésion était sévère (61,1 %), modérée (36,1 %) et légère (2,8 %) sans association significative ni avec la cause ni avec le site lésionnel (p>0,05). Conclusion: Notre étude a permis d’appuyer le rôle de l’ENMG dans l’étude de la plexopathie brachiale post traumatique. Elle a démontré que la topographie et la sévérité des lésions étaient indépendantes des étiologies du traumatisme.   English title: Electroneuromyogram findings of traumatic brachial plexus injuries Background: Electroneuromyogram (ENMG) plays a crucial role in the exploration of the brachial plexus. The purpose of this study was to investigate the electroneuromyographic characteristics of posttraumatic plexus brachial damage and to determine the factors associated with the topography and severity of the lesions. Patients and methods:  A retrospective study was carried out in the Neurology Department of the RAZI University Hospital including patients referred to the electroneurophysiology unit for traumatic brachial plexus damage during the period from January 2003 to June 2018. Demographic, clinical and ENMG’s data results were collected and analyzed. The severity of the lesion was evaluated according to the modified version of the Dumitru and Wilbourn scale. Results:  We collected 36 post-traumatic brachial plexopathies in 35 patients (M / F = 30/5, mean age = 39.3 years). ENMG was performed 3 weeks after trauma in 91.3% of patients. He showed impaired nerve conduction (97.2%), a neurogenic trace (91.7%) and signs of denervation (55.6%). The lesion level concerned the primary trunks (66.7%) and the secondary trunks (33.3%). It was not significantly related to the cause (p> 0.05). The lesion was severe (61.1%), moderate (36.1%) and mild (2.8%) with no significant association with either the cause or the site of injury (p> 0.05). Conclusion:  Our study supported the role of ENMG in the study of post-traumatic brachial plexopathy. It demonstrated that the topography and the severity of the lesions were independent of the etiologies of the trauma. &nbsp

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century