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Clinical laboratory parameters associated with severe or critical novel coronavirus disease 2019 (COVID-19): A
Jude Moutchia1,2, Pratik Pokharel2,3, Aldiona Kerri2,3
1Bamenda Regional Hospital, Bamenda, Cameroon.
Insights
Laboratory markers can predict severe Coronavirus disease 2019 (COVID-19). Severe cases show higher neutrophils and lower lymphocytes, CD4, and CD8 T cells, alongside elevated C-reactive protein, interleukin-6, Troponin I, and D-dimer.
Area of Science:
- Clinical Medicine
- Immunology
- Infectious Diseases
Background:
- Clinical laboratory parameters for Coronavirus disease 2019 (COVID-19) severity lack consistent reporting across studies.
- Identifying reliable biomarkers is crucial for managing COVID-19 patient outcomes.
Purpose of the Study:
- To systematically review and assess clinical laboratory parameters that may predict or indicate severe or critical COVID-19.
- To consolidate evidence on laboratory findings associated with COVID-19 severity.
Main Methods:
- Systematic literature search across major databases (MEDLINE, Embase, Web of Science, CINAHL, Google Scholar) and pre-print servers.
- Inclusion of hospital-based observational studies on confirmed COVID-19 cases, excluding studies with high proportions of children or pregnant women.
- Meta-analysis using random effects model to calculate meta-median differences (MMD) and 95% confidence intervals (CI) for laboratory parameters.
Main Results:
- Severe or critical COVID-19 cases exhibited significantly higher neutrophil counts (MMD: 1.23 ×10^9 cells/L) compared to non-severe cases.
- Marked decreases were observed in lymphocyte, CD4 T cell, and CD8 T cell counts in severe COVID-19.
- Elevated C-reactive protein (MMD: 36.97 mg/L), interleukin-6 (MMD: 17.37 pg/ml), Troponin I (MMD: 0.01 ng/ml), and D-dimer (MMD: 0.65 mg/ml) were associated with severe disease.
Conclusions:
- Severe COVID-19 is characterized by an overactive innate immune response and a suppressed adaptive immune response.
- Increased markers of tissue damage and organ failure are evident in severe cases.
- These identified laboratory markers can aid in recognizing and monitoring the clinical course of severe or critical COVID-19.
Background:
To date, several clinical laboratory parameters associated with Coronavirus disease 2019 (COVID-19) severity have been reported. However, these parameters have not been observed consistently across studies. The aim of this review was to assess clinical laboratory parameters which may serve as markers or predictors of severe or critical COVID-19.
Methods And Findings:
We conducted a systematic search of MEDLINE, Embase, Web of Science, CINAHL and Google Scholar databases from 2019 through April 18, 2020, and reviewed bibliographies of eligible studies, relevant systematic reviews, and the medRxiv pre-print server. We included hospital-based observational studies reporting clinical laboratory parameters of confirmed cases of COVID-19 and excluded studies having large proportions (>10%) of children and pregnant women. Two authors independently carried out screening of articles, data extraction and quality assessment. Meta-analyses were done using random effects model. Meta-median difference (MMD) and 95% confidence interval (CI) was calculated for each laboratory parameter. Forty-five studies in 6 countries were included. Compared to non-severe COVID-19 cases, severe or critical COVID-19 was characterised by higher neutrophil count (MMD: 1.23 [95% CI: 0.58 to 1.88] ×109 cells/L), and lower lymphocyte, CD4 and CD8 T cell counts with MMD (95% CI) of -0.39 (-0.47, -0.31) ×109 cells/L, -204.9 (-302.6, -107.1) cells/μl and -123.6 (-170.6, -76.6) cells/μl, respectively. Other notable results were observed for C-reactive protein (MMD: 36.97 [95% CI: 27.58, 46.35] mg/L), interleukin-6 (MMD: 17.37 [95% CI: 4.74, 30.00] pg/ml), Troponin I (MMD: 0.01 [0.00, 0.02] ng/ml), and D-dimer (MMD: 0.65 [0.45, 0.85] mg/ml).
Conclusions:
Relative to non-severe COVID-19, severe or critical COVID-19 is characterised by increased markers of innate immune response, decreased markers of adaptive immune response, and increased markers of tissue damage and major organ failure. These markers could be used to recognise severe or critical disease and to monitor clinical course of COVID-19.
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