Hematological characteristics of COVID‐19 patients with fever infected by the Omicron variant in Shanghai: A retrospective cohort study in China

Abstract

Background A wave of the Omicron variant of severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) infection has rapidly spread in Shanghai, China. Hematological abnormalities have been reported in coronavirus disease 2019 (COVID‐19) patients; however, the difference in hematological parameters between COVID‐19 patients with fever and patients who are febrile from other causes remains unexplored. Methods This retrospective cohort study enrolled 663 SARS‐CoV‐2 positive patients identified by RT‐PCR. Clinical parameters, including age, sex, and threshold cycle values of all COVID‐19 patients, and hematological parameters of COVID‐19 patients in the fever clinic were abstracted for analysis. Results Overall, 60.8% of COVID‐19 patients were male, and the median age was 45 years. Most of COVID‐19 patients were asymptomatic, while 25.8% of patients showed fever and 10.9% of patients had other emergencies. COVID‐19 patients with fever had significantly lower white blood cells (WBCs), neutrophils, lymphocytes, platelets and C‐reactive protein (CRP), and significantly higher monocyte‐to‐lymphocyte ratio (MLR), platelet‐to‐lymphocyte ratio (PLR), mean platelet volume (MPV), and mean platelet volume‐to‐platelet ratio (MPR) levels, compared with those in SARS‐CoV‐2 negative patients with fever from other causes (p < 0.05). Neutrophil‐to‐lymphocyte ratio (NLR), PLR, and systemic inflammatory index (SII) levels were significantly higher in COVID‐19 patients with emergencies (p < 0.05). WBCs showed the best performance with an area under the curve (0.756), followed by neutrophils (0.730) and lymphocytes (0.694) in the diagnosis of COVID‐19 in the fever clinic. Conclusion WBCs, neutrophils, lymphocytes, platelets, CRP and MLR, PLR, and MPR may be useful in early diagnosis of COVID‐19 in the fever clinic.

Characteristics of hematological parameters on admission in COVID-19 Omicron variant infected in Chinese population: a large-scale retrospective study

“…Furthermore, the ROC curve analysis in the present study observed that a decreased levels of LYM counts (0.738) on admission might be the most valuable hematological parameter for early diagnosis of COVID-19 with fever, followed by the decreased NEU counts (0.718), increased MLR (0.713), increased PLR (0.702), decreased WBC counts (0.700), and decreased MCHC (0.687), which is in concordance with previous report [ 38 ]. These are accessible and affordable hematological parameters that may assist clinicians in making timely differential diagnoses between COVID-19 patients and non-COVID-19 patients with fever.…”

“…It may be due to the toxicity of Omicron was attenuated compared with that of the original strain and other mutants. Additionally, the weakened immune status of pneumonia patients and the suppressed inflammatory response, consistent with earlier publications [ 38 , 52 ].…”

“…In this study, 2021 COVID-19 patients were enrolled, the majority of whom presented with an upper respiratory tract infection with symptoms (66.40%). Furthermore, febrile COVID-19 patients are characterized by a high dominant of females (54.25%) aged 18–60 years (55.51%), similar to previous studies [ 38 , 39 ]. Additionally, the present study’s overall case-lung infection rate was approximately 33.60%.…”

“…Previous research has indicated that hematological parameters can serve as useful prognostic markers in COVID-19 patients [ 37 ]. Nevertheless, on the one hand, small sample-scale previous studies have compared the hematological parameters of Omicron variant-infected patients with fever and SARS-CoV-2 negative patients with fever [ 38 ]. More importantly, few studies have investigated the potential role of hematological parameters in the early identification of the Omicron variant in COVID-19 patients with pulmonary infection.…”

“…Furthermore, previous studies have highlighted that the Ct value of SARS-CoV-2, as determined by RT-qPCR on admission, can not only serve as an indicator of the viral load in COVID-19 patients but also act as an independent predictor for disease progression. Febrile COVID-19 patients exhibit a higher viral load compared to their non-febrile counterparts [ 38 , 62 ]. Given its clinical significance, viral load should ideally be incorporated into our research analysis.…”