RESUMO
A brief unexplained resolved event (BRUE) is an event observed in a child under 1 year of age in which the observer witnesses a sudden, brief but resolved episode of change in skin color, lack of breathing, weakness or poor responsiveness. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of coronavirus disease-2019 (COVID-19). We report the case of a previously healthy, full-term infant infected with SARS-CoV-2 when he was 8 months old. Previous to this event, both his grandfather and great-uncle had died of severe pneumonia and his mother had developed respiratory symptoms and fever. Over the following month he was seen five times in the emergency room and was hospitalized twice for recurrent BRUE. At the first hospital admission, after the second emergency room visit, he twice tested positive for COVID-19 after nasopharyngeal swab tests. During his second hospital admission, after the fifth emergency room visit, chest computed tomography revealed typical SARS-CoV-2 pneumonia. During a follow-up examination 6 months later, mild respiratory distress required administration of inhaled oxygen (0.5 L/min) and chest computed tomography disclosed a slight improvement in pulmonary involvement. The clinical manifestation of pulmonary complications from COVID-19 infection was unusual. This is the first report of an infant at high-risk for BRUE, which was the only manifestation of long-term lung involvement due to SARS-CoV-2 pneumonia.
RESUMO
The cognitive and behavioural deficits caused by traumatic brain injury (TBI) to the immature brain are more severe and persistent than TBI in the mature brain. Understanding this developmental sensitivity is critical as children under four years of age sustain TBI more frequently than any other age group. Microglia (MG), resident immune cells of the brain that mediate neuroinflammation, are activated following TBI in the immature brain. However, the type and temporal profile of this activation and the consequences of altering it are still largely unknown. In a mouse model of closed head weight drop paediatric brain trauma, we characterized i) the temporal course of total cortical neuroinflammation and the phenotype of ex vivo isolated CD11B-positive microglia/macrophage (MG/MΦ) using a battery of 32 markers, and ii) neuropathological outcome 1 and 5days post-injury. We also assessed the effects of targeting MG/MΦ activation directly, using minocycline a prototypical microglial activation antagonist, on these processes and outcome. TBI induced a moderate increase in both pro- and anti-inflammatory cytokines/chemokines in the ipsilateral hemisphere. Isolated cortical MG/MΦ expressed increased levels of markers of endogenous reparatory/regenerative and immunomodulatory phenotypes compared with shams. Blocking MG/MΦ activation with minocycline at the time of injury and 1 and 2days post-injury had only transient protective effects, reducing ventricular dilatation and cell death 1day post-injury but having no effect on injury severity at 5days. This study demonstrates that, unlike in adults, the role of MG/MΦ in injury mechanisms following TBI in the immature brain may not be negative. An improved understanding of MG/MΦ function in paediatric TBI could support translational efforts to design therapeutic interventions.
