Tocilizumab and COVID-19: Timing of administration assessment.

Recent evidence showed greater efficacy of tocilizumab (TCZ) in the subgroups of COVID-19 patients who presented with symptoms for less than 7 days and in those only receiving oxygen. We retrospectively analyzed a compassionate use cohort to determine the best timing for TCZ injection. We showed no association between the timing of injection after symptom onset and the efficacy of TCZ on mortality. We then investigated whether the oxygen level at the time of TCZ injection impacted the mortality rate. Our study finally suggested that TCZ could be less effective when oxygen requirement is >11L/min and we hypothesized that earlier administration could be associated with better outcome. However, randomized clinical trials are required to confirm this hypothesis.

[COVID-19: Pathogenesis of a multi-faceted disease]. / COVID-19 : physiopathologie d'une maladie à plusieurs visages.

SARS-CoV-2 infection, named COVID-19, can lead to a dysregulated immune response and abnormal coagulation responsible for a viral sepsis. In this review, we specify physiopathological mechanisms of each phase of COVID-19 - viral, immune and pro-thrombotic - notably because they involve different treatment. Finally, we specify the physiopathological mechanisms of organ injury.

[COVID-19: Clinical, biological and radiological characteristics in adults, infants and pregnant women. An up-to-date review at the heart of the pandemic]. / COVID-19 : caractéristiques cliniques, biologiques et radiologiques chez l'adulte, la femme enceinte et l'enfant. Une mise au point au cœur de la pandémie.

The spread of the new coronavirus SARS-CoV-2, discovered in China in January 2020, led to a pandemic as early as March 2020, forcing every health care system in the affected countries to adapt quickly. In order to better address this major health crisis, which has given rise to numerous scientific publications, we have synthesized the main original clinical studies to facilitate the day-to-day management of patients with COVID-19. We detail the early signs and progression of the disease as well as the different clinical forms, including extra-pulmonary, as known at the beginning of this pandemic. We focus on clinical, biological and CT markers predictive of severity or mortality. Finally, we discuss the impact of SARS-CoV-2 infection in populations suspected to be at high risk of severe forms.