The Relation between RT-PCR and Chest CT Scan Sensitivity as Tools in the Diagnosis of COVID-19 Patients in Al-Najaf Province, Iraq

  • Layth Abdulmajeed Abdulkhaleq Department of Pathology and Poultry Disease, Collage of Veterinary Medicine, University of Bagdad, Iraq.
  • Moutaz AW Abdul Mounan Department of Vet. Public Health, Collage of Veterinary Medicine, University of Bagdad, Iraq.
  • Walaa F Obead Department of Anatomy and Histology, Collage of Veterinary Medicine, University of Kerbala, Iraq.
Keywords: RT-PCR, Chest CT Scan, COVID-19, Sensitivity, Specificity


The typical test for diagnosis of severe acute respiratory syndrome coronavirus 2 is a reverse transcription-polymerase chain reaction (RT-PCR) technique, but the chest CT scan might play a complementary role at the first detection of Coronavirus Disease 2019 (COVID-19) pneumonia.

Objectives: To determine the sensitivity of CT scan on patients with COVID-19 in Al-Najaf, Iraq, and to compare the accuracy of CT scan with that of RT-PCR technique.

Material and Method: This is a prospective study. The patients suspicious of having COVID-19 infection and respiratory symptoms were registered. All patients were diagnosed by RT-PCR and chest CT. Diagnostic performance of CT was intended using RT-PCR as the reference standard in the centre of coronavirus investigation in Al-Najaf city, Iraq from March 2020 to September 2020.

Results: The study population included 125 consecutive participants (males and females; mean age = 53 ± 17 years). Of the 125 participants, fever was observed in 93 (74.4%), cough was observed in 81 (64.8%), dyspnoea was observed in 47 (33%), and lymphocytopenia was observed in 89 (71.2%) subjects. The sensitivity and specificity of chest CT scan was 94% (95% confidence interval).

Conclusion: The typical diagnosis of Coronavirus Disease 2019 pneumonia is by RT-PCR at the first stage of infection which can then be confirmed by chest CT.

How to cite this article:
Abdulkhaleq LA, Mounan MAWA, Obead FW. The Relation between RT-PCR and Chest CT Scan Sensitivity as Tools in the Diagnosis of COVID-19 Patients in Al-Najaf Province, Iraq. J Commun Dis. 2021;53(4):114-118.



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