Hematological findings in adult patients with SARS CoV‐2 infection at Tygerberg Hospital Cape Town South Africa

BACKGROUND: Coronavirus disease 2019 (COVID‐19) is associated with hematological abnormalities of variable severity. The full blood count (FBC) and leukocyte differential count (DIFF) could facilitate the prediction of disease severity and outcome in COVID‐19. This study aimed to assess the hematological parameters in early severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) infection and their correlation with disease outcome. METHODS: A retrospective cross‐sectional descriptive study was performed. Adults with a FBC and positive SARS‐CoV‐2 polymerase chain reaction results between March 1, and June 31, 2020 were reviewed. Basic hematological parameters (FBC, DIFF) and human immunodeficiency virus (HIV) status were recorded. Outcome measures were admission to a general ward or intensive care unit (ICU), recovery or death. RESULTS: Six hundred and eighty‐five cases median age 51 years, were analyzed. Forty‐four percent were males and fourteen percent were HIV‐positive with no association between death and/or ICU admission (p = 0.522 and p = 0.830, respectively). Leucocytosis was predictive of ICU admission (odds ratio [OR]: 2.4, confidence interval [CI]: 1.77–3.8186) and neutrophilia, of both mortality (OR: 1.5, CI: 1.0440–2.0899) and ICU admission (OR: 4, CI: 2.5933–6.475). Median lymphocyte count was decreased and d‐dimer raised, showing no significant association with outcome. Raised neutrophil‐to‐lymphocyte‐ratio (NLR) was associated with increased odds of mortality (OR: 2.5, CI: 1.3556–3.2503) and ICU admission (OR: 4.8, CI: 2.4307–9.5430) as was monocyte‐to‐lymphocyte‐ratio (MLR) (OR: 2, CI: 1.3132–2.9064) and (OR: 2.3, CI: 1.0608–1.9935), respectively. Hospital admission and older age were significantly associated with mortality (p = 0.0008 and p < 0.0001), respectively. CONCLUSION: Evidence‐based interpretation of routine laboratory parameters, readily available in resource‐constrained settings, may identify patients at increased risk of mortality. The FBC, DIFF, NLR, and MLR should form part of the early COVID‐19 investigation.