Comparison of immunological profiles and laboratory parameters in patients admitted to ICUs during different SARS-CoV-2 outbreaks.
inflammation; covid-19; vitamin D
The prognosis of covid-19 relies on several factors, including the immune response of the patient, metabolic and nutritional status and the genetic characteristics of the virus. This study investigated the inflammatory profile, oxidative stress and vitamin D levels in patients admitted to intensive care units at Hospital do Coração (HC) and Hospital Giselda Trigueiro (HGT), infected with original and Gamma strains of SARS-CoV-2, respectively. Patients with positive RT-PCR were organized into two groups: the first group had their blood collected from April to May 2020 (HC). The second group had blood collected in January 2021 (HGT). Global and differential leukocyte counts, neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), systemic levels of C-reactive protein, lactate dehydrogenase (LDH), creatinine, vitamin D, malondialdehyde (MDA) and cytokines and chemokines were assessed. Based on hematological characteristics and blood marker levels, two different groups were characterized, showing that HGT patients had a higher number of leukocytes, mainly neutrophils, with higher proportions of NLR and PLR when compared to HC patients. Furthermore, higher levels of LDH, CXCL8 and MDA and lower levels of vitamin D, GM-CSF and IFN-g were found in HGT patients. The neutrophilia observed together with elevated levels of CXCL8 and LDH in HGT patients suggests greater susceptibility to the occurrence of pyroptosis and NETosis, which may play an important role in the severity of lung damage and systemic compromise during covid-19 caused by the Gamma variant, in contrast with patients with the original strain