Israel Medical Association Journal

Background: Immune cell counts in blood in severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection may be useful prognostic biomarkers of disease severity, mortality, and response to treatment.

Objectives: To analyze sub-populations of lymphocytes at hospital admission in survivors and deceased from severe pneumonia due to coronavirus disease-2019 (COVID-19).

Methods: We conducted a cross-sectional study of healthcare workers confirmed with SARS-CoV-2 in convalescents (control group) and healthy controls (HC) diagnosed with severe COVID-19. Serum samples were taken at hospital admission and after recovery. Serum samples ≥ 25 days after onset of symptoms were analyzed for lymphocyte subpopulations through flow cytometry. Descriptive statistics, Kruskall-Wallis test, receiver operating characteristic curve, calculation of sensitivity, specificity, predictive values, and Kaplan-Meier analysis were performed.

Results: We included 337 patients: 120 HC, 127 convalescents, and 90 severe COVID-19 disease patients (50 survivors, 40 deceased). For T cells, total lymphocytes ≥ 800/μL, CD3+ ≥ 400/μL, CD4+ ≥ 180/μL, CD8+ ≥ 150/μL, B cells CD19+ ≥ 80/μL, and NK ≥ 34/μL subsets were associated with survival in severe COVID-19 disease patients. All subtypes of lymphocytes had higher concentrations in survivors than deceased, but similar between HC and convalescents. Leukocytes ≥ 10.150/μL or neutrophils ≥ 10,000/μL were associated with increased mortality. The neutrophil-to-lymphocyte ratio (NLR) ≥ 8.5 increased the probability of death in severe COVID-19 (odds ratio 11.68).

Conclusions: Total lymphocytes; NLR; and levels of CD3+, CD4+, CD8+, and NK cells are useful as biomarkers of survival or mortality in severe COVID-19 disease and commonly reach normal levels in convalescents.

Background: There is limited clinical information on coronavirus disease-19 (COVID-19) patients in Israel.

Objectives: To describe the characteristics, outcomes, and potential associations of hospitalized COVID-19 patients in Israel.

Methods: We conducted a single-center, retrospective study of 58 consecutive laboratory-confirmed COVID-19 patients admitted to Laniado Hospital, Israel, between 14 March 2020 and 14 May 2020. Demographic, clinical, and laboratory data on admission were collected and analyzed, and the association to subsequent respiratory failure was assessed.

Results: Mean age of patients was 70.7 ± 16.9 years (53% males, 47% females.); 74% had at least one co-morbidity. Most patients were of Jewish Ashkenazi descent. During hospitalization 15 patients (mean age 78.18 ± 10.35 years); 80% male, 73% Sephardi descent developed respiratory failure rates of 60% occurring on average 10.6 days following intubation. Laboratory tests at admission displayed a significant increase in C-reactive protein (CRP) and creatine kinase (CK) and a decrease in absolute lymphocyte count (ALC) in patients who eventually developed respiratory failure (163.97 mg/L, 340.87 IU/L, 0.886 K/μl vs. 50.01 mg/L and 123.56 IU/L, 1.28 K/μl, respectively). Multivariate logistic analysis revealed an integrated parameter of CRP, CK, and ALC highly correlated with respiratory failure. Receiver operating characteristic curve revealed the area under the curve of CRP, CK, and ALC and the integrated parameter to be 0.910, 0.784, and 0.754, respectively. CRP was the strongest predictor to correlate with respiratory failure.

Conclusions: CRP, CK, and ALC levels on admission could possibly be used to detect high-risk patients prone to develop respiratory failure.