Patients at Risk of Pulmonary Fibrosis Post Covid-19: Pulmonary Sequelae and Humoral Response

Abstract

Background: The COVID-19 pandemic is one of the major public health problems. The aim of this study is to characterize patients hospitalized for COVID-19 pneumonia at risk of pulmonary fibrosis and to know the amount of protective antibodies and their permanence in these patients.

Methods: Follow-up study of the humoral response in hospitalized patients at risk of pulmonary fibrosis post-COVID-19 who were followed up for one year after hospital discharge.

Results: The study included 72 patients, 52 of whom had pre-existing chronic comorbidities. COVID-19 clinical severity was rated in 6% as mild, 58% as moderate and 36% as severe. After one year follow-up, forty percent had pulmonary sequelae, the most frequent being mild pulmonary fibrosis. All patients presented RBD IgG, 88% IgA after 8-9 months. The amount of RBD IgG was similar at 4-5 and 8-9 months post-COVID-19. There was no difference in RBD IgG level according to COVID-19 severity (P = .441, P = .594).

Conclusions: The amount of RBD IgG is maintained throughout the convalescent phase and could protect against new reinfections in patients at risk of pulmonary fibrosis Post Covid-19. However, it does not seem to predict the development or not of pulmonary fibrosis.