Amin Sepehr - Department of Bacteriology, Pasteur Institute of Iran, Tehran, Iran.
Sepideh Fereshteh - Department of Bacteriology, Pasteur Institute of Iran, Tehran, Iran.

Background and Aim : The recent outbreak of SARS-CoV-۲ has spread all over the world.Evaluation of laboratory parameters in suspected patients is a vital issue for rapid and accuratediagnosis of COVID-۱۹, which improves the survival of the patients.Methods : This study was performed on ۴۹۸۷ participants suspected of SARS-CoV-۲ referred toa medical diagnostic laboratory in Tehran, Iran, from March ۲۰۲۰ to September ۲۰۲۰. Real-timePCR was performed for the detection of the N and Orf۱ab genes. Blood test evaluation wasperformed by examining white blood cell count (WBC), lymphocyte count (Lymph), C-reactiveprotein (CRP), and IgM and IgG antibodies. Data analysis was done using the receiver operatingcharacteristic curve analysis method to evaluate the accuracy of the test.Results : The RT-PCR was positive in ۱۲.۶۵% of cases. The CRP level and WBC count weresignificantly different between the positive and negative groups (P-value <۰.۰۰۱). The leukopeniawas observed in ۴۴% of infected patients in the group with cycle time (CT) ۱۵-۳۱. The accuracyof the CRP test was in the low range, whereas the accuracy of other laboratory serologicalparameters and antibody tests was poor (P-value <۰.۰۰۱).Conclusion : According to obtained results, RT-PCR is the standard gold method for SARS-CoV-۲ diagnosis. IgM-IgG antibodies levels and other clinical laboratory tests such as WBC,lymphocyte, and CRP can provide an overall picture of the patient's health status and predictionof the infection stage. No blood test by itself is reliable for determining the status of SARS-CoV-۲.

SARS-CoV-۲, C-reactive protein, COVID-۱۹, Leukopenia.