Admission High-Sensitive Cardiac Troponin T Level Increase Is Independently Associated with Higher Mortality in Critically Ill Patients with COVID-19: A Multicenter Study.

BACKGROUND: In coronavirus disease 2019 (COVID-19) patients, increases in high-sensitive cardiac troponin T (hs-cTnT) have been reported to be associated with worse outcomes. In the critically ill, the prognostic value of hs-cTnT, however, remains to be assessed given that most previous studies have involved a case mix of non- and severely ill COVID-19 patients. METHODS: We conducted, from March to May 2020, in three French intensive care units (ICUs), a multicenter retrospective cohort study to assess in-hospital mortality predictability of hs-cTnT levels in COVID-19 patients. RESULTS: 111 laboratory-confirmed COVID-19 patients (68% of male, median age 67 (58-75) years old) were included. At ICU admission, the median Charlson Index, Simplified Acute Physiology Score II, and PaO2/FiO2 were at 3 (2-5), 37 (27-48), and 140 (98-154), respectively, and the median hs-cTnT serum levels were at 16.0 (10.1-31.9) ng/L. Seventy-five patients (68%) were mechanically ventilated, 41 (37%) were treated with norepinephrine, and 17 (15%) underwent renal replacement therapy. In-hospital mortality was 29% (32/111) and was independently associated with lower PaO2/FiO2 and higher hs-cTnT serum levels. CONCLUSIONS: At ICU admission, besides PaO2/FiO2, hs-cTnT levels may allow early risk stratification and triage in critically ill COVID-19 patients.

Receptor binding domain-IgG levels correlate with protection in residents facing SARS-CoV-2 B.1.1.7 outbreaks.

BACKGROUND: Limited information exists on nursing home (NH) residents regarding BNT162b2 vaccine efficacy in preventing SARS-CoV-2 and severe COVID-19, and its association with post-vaccine humoral response. METHODS: 396 residents from seven NHs suffering a SARS-CoV-2 B.1.1.7 (VOC-α) outbreak at least 14 days after a vaccine campaign were repeatedly tested using SARS-CoV-2 real-time reverse-transcriptase polymerase chain reaction on nasopharyngeal swab test (RT-qPCR). SARS-CoV-2 receptor-binding domain (RBD) of the S1 subunit (RBD-IgG) was measured in all residents. Nucleocapsid antigenemia (N-Ag) was measured in RT-qPCR-positive residents and serum neutralizing antibodies in vaccinated residents from one NH. RESULTS: The incidence of positive RT-qPCR was lower in residents vaccinated by two doses (72/317; 22.7%) vs one dose (10/31; 32.3%) or non-vaccinated residents (21/48; 43.7%; p < .01). COVID-19-induced deaths were observed in 5 of the 48 non-vaccinated residents (10.4%), in 2 of the 31 who had received one dose (6.4%), and in 3 of the 317 (0.9%) who had received two doses (p = .0007). Severe symptoms were more common in infected non-vaccinated residents (10/21; 47.6%) than in infected vaccinated residents (15/72; 21.0%; p = .002). Higher levels of RBD-IgG (n = 325) were associated with a lower SARS-CoV-2 incidence. No in vitro serum neutralization activity was found for RBD-IgG levels below 1050 AU/ml. RBD-IgG levels were inversely associated with N-Ag levels, found as a risk factor of severe COVID-19. CONCLUSIONS: Two BNT162b2 doses are associated with a 48% reduction of SARS-CoV-2 incidence and a 91.3% reduction of death risk in residents from NHs facing a VOC-α outbreak. Post-vaccine RBD-IgG levels correlate with BNT162b2 protection against SARS-CoV-2 B.1.1.7.

Analytical evaluation of the novel VITROS BRAHMS procalcitonin immunoassay.

To determine the analytical performance of Novel VITROS BRAHMS Procalcitonin Immunoassay on VITROS 3600 and correlation with BRAHMS PCT sensitive KRYPTOR reference method. Analytical performances including imprecision studies, linearity, limit of detection (LoD) and determination of hemolysis index were performed for VITROS BRAHMS PCT assay. Imprecision was assessed on plasma pool and internal control with 2 levels. The method comparison was performed using 162 plasma obtained from clinical departments. The total imprecision was acceptable and all CV were <5%. The LoD was in accordance with manufacturer's claims. The equation of linearity in the lower range was found to be y = 1.0014x - 0.0091, with r2 = 1. No interference to hemoglobin up to 11 g/L was observed. Correlation studies showed a good correlation between PCT measurements using VITROS BRAHMS PCT assay against KRYPTOR system including for values lower than 2 µg/L. The novel VITROS BRAHMS PCT assay from OrthoClinical Diagnostics shows analytical performances acceptable for clinical use. In addition, the concordance with KRYPTOR method was fine at all clinical cut-offs.