ABSTRACT
Given the various clinical manifestations that characterize COVID-19, the scientific community is constantly searching for biomarkers with prognostic value. SP-A and SP-D collectins play a crucial role in ensuring proper alveolar function and an alteration of their serum levels have been reported in several pulmonary diseases characterized by ARDS and pulmonary fibrosis. Considering that such clinical manifestations can also occur during SARS-CoV-2 infection, we wondered if these collectins could act as prognostic markers. In this regard, serum levels of SP-A and SP-D were measured by enzyme immunoassay in patients with SARS-CoV-2 infection (n=51) at admission (T0) and after 7 days (T1) and compared with healthy donors (n=11). SP-D increased in COVID-19 patients compared to healthy controls during the early phases of infection, while a significant reduction was observed at T1. Stratifying SARS-CoV-2 patients according to disease severity, increased serum SP-D levels were observed in severe compared to mild patients. In the light of these results SP-D, but not SP-A, seems to be an eligible marker of COVID-19 pneumonia and the early detection of SP-D serum levels could be crucial for a preventive clinical management