Clinical phenotypes and outcomes associated with SARS-CoV-2 variant Omicron in critically ill French patients with COVID-19.

Infection with SARS-CoV-2 variant Omicron is considered to be less severe than infection with variant Delta, with rarer occurrence of severe disease requiring intensive care. Little information is available on comorbid factors, clinical conditions and specific viral mutational patterns associated with the severity of variant Omicron infection. In this multicenter prospective cohort study, patients consecutively admitted for severe COVID-19 in 20 intensive care units in France between December 7th 2021 and May 1st 2022 were included. Among 259 patients, we show that the clinical phenotype of patients infected with variant Omicron (n = 148) is different from that in those infected with variant Delta (n = 111). We observe no significant relationship between Delta and Omicron variant lineages/sublineages and 28-day mortality (adjusted odds ratio [95% confidence interval] = 0.68 [0.35-1.32]; p = 0.253). Among Omicron-infected patients, 43.2% are immunocompromised, most of whom have received two doses of vaccine or more (85.9%) but display a poor humoral response to vaccination. The mortality rate of immunocompromised patients infected with variant Omicron is significantly higher than that of non-immunocompromised patients (46.9% vs 26.2%; p = 0.009). In patients infected with variant Omicron, there is no association between specific sublineages (BA.1/BA.1.1 (n = 109) and BA.2 (n = 21)) or any viral genome polymorphisms/mutational profile and 28-day mortality.

Convalescent plasma therapy for B-cell-depleted patients with protracted COVID-19.

Anti-CD20 monoclonal antibodies are widely used for the treatment of hematological malignancies or autoimmune disease but may be responsible for a secondary humoral deficiency. In the context of COVID-19 infection, this may prevent the elicitation of a specific SARS-CoV-2 antibody response. We report a series of 17 consecutive patients with profound B-cell lymphopenia and prolonged COVID-19 symptoms, negative immunoglobulin G (IgG)-IgM SARS-CoV-2 serology, and positive RNAemia measured by digital polymerase chain reaction who were treated with 4 units of COVID-19 convalescent plasma. Within 48 hours of transfusion, all but 1 patient experienced an improvement of clinical symptoms. The inflammatory syndrome abated within a week. Only 1 patient who needed mechanical ventilation for severe COVID-19 disease died of bacterial pneumonia. SARS-CoV-2 RNAemia decreased to below the sensitivity threshold in all 9 evaluated patients. In 3 patients, virus-specific T-cell responses were analyzed using T-cell enzyme-linked immunospot assay before convalescent plasma transfusion. All showed a maintained SARS-CoV-2 T-cell response and poor cross-response to other coronaviruses. No adverse event was reported. Convalescent plasma with anti-SARS-CoV-2 antibodies appears to be a very promising approach in the context of protracted COVID-19 symptoms in patients unable to mount a specific humoral response to SARS-CoV-2.

Acute kidney injury in patients with SARS-CoV-2 infection.

BACKGROUND: Acute Kidney Injury (AKI) is a frequent complication of severe SARS-CoV-2 infection. Multiple mechanisms are involved in COVID-19-associated AKI, from direct viral infection and secondary inflammation to complement activation and microthrombosis. However, data are limited in critically-ill patients. In this study, we sought to describe the prevalence, risk factors and prognostic impact of AKI in this setting. METHODS: Retrospective monocenter study including adult patients with laboratory confirmed SARS-CoV-2 infection admitted to the ICU of our university Hospital. AKI was defined according to both urinary output and creatinine KDIGO criteria. RESULTS: Overall, 100 COVID-19 patients were admitted. AKI occurred in 81 patients (81%), including 44, 10 and 27 patients with AKI stage 1, 2 and 3 respectively. The severity of AKI was associated with mortality at day 28 (p = 0.013). Before adjustment, the third fraction of complement (C3), interleukin-6 (IL-6) and ferritin levels were higher in AKI patients. After adjustment for confounders, both severity (modified SOFA score per point) and AKI were associated with outcome. When forced in the final model, C3 (OR per log 0.25; 95% CI 0.01-4.66), IL-6 (OR per log 0.83; 95% CI 0.51-1.34), or ferritin (OR per log 1.63; 95% CI 0.84-3.32) were not associated with AKI and did not change the model. CONCLUSION: In conclusion, we did not find any association between complement activation or inflammatory markers and AKI. Proportion of patients with AKI during severe SARS-CoV-2 infection is higher than previously reported and associated with outcome.