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Published on: June 5, 2021
Similar Kinetics of Pulmonary SARS-CoV-2 Load in Intensive Care Unit Patients with COVID-19 Pneumonia with or Without
Valentine Le Stang1, Paul Bastard2,3,4,5, Elise Langouet1
1Médecine Intensive Réanimation, Sorbonne Université, Groupe Hospitalier Pitié-Salpêtrière, Assistance Publique - Hôpitaux de Paris (AP-HP), Paris, France.
Purpose:
The pathogenesis of life-threatening coronavirus disease 2019 (COVID-19) pneumonia in ICU patients can involve pre-existing auto-antibodies (auto-Abs) neutralizing type I interferons (IFNs). The impact of these auto-Abs on SARS-CoV-2 clearance in the lower respiratory tract (LRT) is unclear.
Methods:
We performed a retrospective study in 99 ICU patients with COVID-19 pneumonia between March and May 2020. LRT SARS-CoV-2 load (intensity and duration) was analyzed according to the presence or not of circulating auto-Abs neutralizing type I IFNs.
Results:
Among the 99 included patients, 38 (38%) were positive for auto-Abs neutralizing type I IFNs, with 5 (5%) harboring auto-Abs neutralizing IFN-α2 at any concentration, while 33 (33%) had auto-Abs neutralizing only IFN-ω at the lower concentration. SARS-CoV-2 load in the LRT and duration of viral shedding, were similar in patients with or without auto-Abs neutralizing type I IFNs. Patients with auto-Abs had the same mortality than those without auto-Abs, despite greater occurrence of renal failure and ECMO support, and longer duration of mechanical ventilation and ICU stay.
Conclusion:
In summary, 5% of patients with critical COVID-19 pneumonia carried auto-Abs neutralizing IFN-α2, while about 1/3 harbored auto-Abs neutralizing low concentrations of IFN-ω. The detection of either type of auto-Abs did not impact LRT viral clearance and mortality, although it was associated with greater morbidity and a longer hospitalization. These findings suggest that similar albeit hitherto unknown mechanisms of disease drive critical COVID-19 pneumonia in patients without auto-Abs against type I IFNs.
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