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Hematological changes associated with COVID-19 infection
Enass Abdul Kareem Dagher Al-Saadi1, Marwa Ali Abdulnabi2
1Department of Pathology, College of Medicine, University of Kerbala, Kerbala, Iraq.
Insights
Monitoring blood markers in COVID-19 patients can predict disease severity. Hematological changes like lymphopenia and elevated D-dimer indicate a higher risk of adverse outcomes in severe cases.
Area of Science:
- Infectious Diseases
- Hematology
- Clinical Biochemistry
Background:
- The COVID-19 pandemic significantly strains global health services.
- While PCR confirms infection, hematological and biochemical markers aid in risk stratification and outcome prediction.
- Mutated virus strains exacerbate spread and health system constraints.
Purpose of the Study:
- To review hematological changes in COVID-19.
- To highlight the diagnostic and prognostic significance of blood indices and biochemical markers.
- To summarize findings across different stages of COVID-19 infection.
Main Methods:
- Conducted a literature search for studies on hematological manifestations and COVID-19.
- Included English-language articles on human samples from December 2019 to January 2021.
- Utilized keywords such as "hematological," "lymphopenia," "platelet," and "COVID-19."
Main Results:
- No hematological changes were noted in asymptomatic or presymptomatic COVID-19 patients.
- Subtle changes, primarily lymphocytopenia (80.4%), were observed in non-severe cases.
- In severe/critical cases with cytokine storm, neutrophilia, lymphocytopenia, elevated D-dimer, prolonged PT, and reduced fibrinogen predict adverse outcomes.
Conclusions:
- Hematological monitoring helps predict patients needing intensive care and stratify risk for severe COVID-19.
- Further research in Iraq is needed to compare local hematological findings with global data.
- Hematological markers are crucial for assessing disease progression and prognosis.
Background:
The unresolved COVID-19 pandemic considerably impacts the health services in Iraq and worldwide. Consecutive waves of mutated virus increased virus spread and further constrained health systems. Although molecular identification of the virus by polymerase chain reaction is the only recommended method in diagnosing COVID-19 infection, radiological, biochemical, and hematological studies are substantially important in risk stratification, patient follow-up, and outcome prediction.
Aim:
This narrative review summarized the hematological changes including the blood indices, coagulative indicators, and other associated biochemical laboratory markers in different stages of COVID-19 infection, highlighting the diagnostic and prognostic significance.
Methods:
Literature search was conducted for multiple combinations of different hematological tests and manifestations with novel COVID-19 using the following key words: "hematological," "complete blood count," "lymphopenia," "blood indices," "markers" "platelet" OR "thrombocytopenia" AND "COVID-19," "coronavirus2019," "2019-nCoV," OR "SARS-CoV-2." Articles written in the English language and conducted on human samples between December 2019 and January 2021 were included.
Results:
Hematological changes are not reported in asymptomatic or presymptomatic COVID-19 patients. In nonsevere cases, hematological changes are subtle, included mainly lymphocytopenia (80.4%). In severe, critically ill patients and those with cytokine storm, neutrophilia, lymphocytopenia, elevated D-dimer, prolonged PT, and reduced fibrinogen are predictors of disease progression and adverse outcome.
Conclusion:
Monitoring hematological changes in patients with COVID-19 can predict patients needing additional care and stratify the risk for severe course of the disease. More studies are required in Iraq to reflect the hematological changes in COVID-19 as compared to global data.
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