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Cq values as an indicator for COVID-19 outcomes: A study of the correlation between laboratory parameters
Hadi Safdari1, Saeede Bagheri1, Nasrin Talkhi2
1Department of Laboratory Sciences, School of Paramedical Sciences, Faculty of Paramedical and Rehabilitation Sciences, Mashhad University of Medical Sciences, Mashhad, Iran.
Insights
Cycle quantitation (Cq) levels correlate with key laboratory markers in COVID-19 patients. These findings suggest Cq values combined with routine lab tests can aid in understanding COVID-19 disease progression.
Area of Science:
- Infectious Diseases
- Clinical Chemistry
- Hematology
Background:
- The COVID-19 pandemic poses a significant global health challenge.
- Understanding disease markers is crucial for patient management.
Purpose of the Study:
- To investigate the relationship between cycle quantitation (Cq) values and various laboratory parameters in COVID-19 patients.
- To assess the potential of Cq levels as an indicator of disease severity.
Main Methods:
- A study involving 234 participants, divided into COVID-19 cases and controls.
- Real-time PCR for COVID-19 diagnosis.
- Analysis of complete blood count, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), lactate dehydrogenase (LDH), D-dimer, IgG, and IgM levels.
Main Results:
- COVID-19 patients showed elevated neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), D-dimer, ESR, CRP, and LDH.
- Lower lymphocyte and platelet counts were observed in COVID-19 cases.
- Significant correlations were found between Cq levels and lymphocyte count (positive) and NLR (inverse).
Conclusions:
- Cq levels are significantly associated with inflammatory markers (CRP, ESR), coagulation markers (D-dimer), and ratios like NLR and PLR in COVID-19.
- Integrating Cq values with laboratory parameters may offer a valuable prognostic tool for COVID-19.
Objective:
The ongoing outbreak of the respiratory disease coronavirus disease 2019 (COVID-19) is currently presenting a major global health threat. This pandemic is unprecedented in recent human history. The objective of this study was to examine the relationship between cycle quantitation (Cq) and laboratory parameters in COVID-19 patients, aiming to determine if Cq levels can provide valuable insights into the COVID-19 disease.
Methods:
This study involved 234 participants who were divided into case and control groups. Real-time PCR tests were used to diagnose COVID-19 cases in the study participants. Blood tests, including complete blood count, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), lactate dehydrogenase (LDH), D-dimer, IgG, and IgM, were also conducted. Statistical analysis was performed using SPSS 22 software.
Results:
The findings showed that COVID-19-positive cases had significantly higher levels of the neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), D-dimer, ESR, CRP, and LDH compared to normal cases. Additionally, the case group had significantly lower lymphocyte and platelet counts. There was a statistically significant positive correlation between Cq levels and lymphocyte count (r = .124, p = .014). Conversely, there was a statistically significant inverse correlation between Cq levels and NLR (r = -.208, p = .017). Furthermore, the evaluation of hematological, inflammatory, and biochemical indexes in COVID-19 patients using the receiver-operating characteristics curve demonstrated statistically appropriate sensitivity and specificity.
Conclusion:
Our outcomes indicated a significant association between Cq levels and PLR, NLR, D-dimer, CRP, and ESR in COVID-19 patients. Consequently, including the report of laboratory parameters alongside Cq values offers a promising prognosis.
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