The dynamics of quantitative SARS-CoV-2 antispike IgG response to BNT162b2 vaccination.

Vaccination for SARS-CoV-2 is necessary to overcome coronavirus disease 2019 (COVID-19). However, the time-dependent vaccine-induced immune response is not well understood. This study aimed to investigate the dynamics of SARS-CoV-2 antispike immunoglobulin G (IgG) response. Medical staff participants who received two sequential doses of the BNT162b2 vaccination on days 0 and 21 were recruited prospectively from the Musashino Red Cross Hospital between March and May 2021. The quantitative antispike receptor-binding domain (RBD) IgG antibody responses were measured using the Abbott SARS-CoV-2 IgGII Quant assay (cut off ≥50 AU/ml). A total of 59 participants without past COVID-19 history were continuously tracked with serum samples. The median age was 41 (22-75) years, and 14 participants were male (23.7%). The median antispike RBD IgG and seropositivity rates were 0 (0-31.1) AU/ml, 0.3 (0-39.5) AU/ml, 529.1 (48.3-8711.4) AU/ml, 18,836.9 (742.2-57,260.4) AU/ml, and 0%, 0%, 98.3%, and 100% on days 0, 3, 14, and 28 after the first vaccination, respectively. The antispike RBD IgG levels were significantly increased after day 14 from vaccination (p < 0.001) The BNT162b2 vaccination led almost all participants to obtain serum antispike RBD IgG 14 days after the first dose.

Liver injury with COVID-19 based on gastrointestinal symptoms and pneumonia severity.

BACKGROUND/AIM: The coronavirus disease 2019 (COVID-19) had become a big threat worldwide. Liver injury is not uncommon in patients with COVID-19, and clarifying its characteristics is needed. This study aimed to identify factors associated with liver injury and to develop a new classification of predictive severity in patients with COVID-19. METHODS: Confirmed patients with COVID-19 (n = 60) were recruited retrospectively from Musashino Red Cross Hospital. The factors of liver injury especially on the elevation of liver enzymes (aspartate aminotransferase [AST] and alanine aminotransferase [ALT]) were analyzed. Grading was assessed according to the Common Terminology Criteria for Adverse Events (CTCAE) version 5.0. RESULTS: During a median hospitalization follow-up of 15 (4-41) days, 51 (85.0%) patients had COVID-19 pneumonia. In clinical courses, oxygenation was needed for 25 (41.6%) patients and intubation was needed for 9 (15.0%) patients. A total of 27 (45.0%) patients had gastrointestinal symptoms (GS), such as appetite loss, diarrhea, and nausea. A logistic regression analysis revealed that C-reactive protein (CRP) at baseline, oxygenation, intubation, and GS were significant factors of liver injury. Based on these results, patients were classified into three groups: group 1, no oxygenation pneumonia; group 2, pneumonia with oxygenation or GS; and group 3, intubation. We classified 25 (41.7%), 26 (43.3%), and 9 (15.0%) patients into mild, moderate, and severe groups, respectively. The peak of AST and ALT levels was significantly stratified with this criteria (mild [median AST, 28 IU/L; median ALT, 33 IU/L], moderate [median AST, 48 IU/L; median ALT, 47.5 IU/L], and severe [median AST, 109 IU/L; median ALT, 106 IU/L]; P<0.001 and P = 0.0114, respectively). CONCLUSION: COVID-19-related liver injury was significantly stratified based on GS and severity of pneumonia.