Diagnosis of the Coronavirus disease (COVID-19): rRT-PCR or CT?

Eur J Radiol. 2020 May:126:108961. doi: 10.1016/j.ejrad.2020.108961. Epub 2020 Mar 25.

Abstract

Purpose: To evaluate the diagnostic value of computed tomography (CT) and real-time reverse-transcriptase-polymerase chain reaction (rRT-PCR) for COVID-19 pneumonia.

Methods: This retrospective study included all patients with COVID-19 pneumonia suspicion, who were examined by both CT and rRT-PCR at initial presentation. The sensitivities of both tests were then compared. For patients with a final confirmed diagnosis, clinical and laboratory data, in addition to CT imaging findings were evaluated.

Results: A total of 36 patients were finally diagnosed with COVID-19 pneumonia. Thirty-five patients had abnormal CT findings at presentation, whereas one patient had a normal CT. Using rRT-PCR, 30 patients were tested positive, with 6 cases initially missed. Amongst these 6 patients, 3 became positive in the second rRT-PCR assay(after 2 days, 2 days and 3 days respectively), and the other 3 became positive only in the third round of rRT-PCR tests(after 5 days, 6 days and 8 days respectively). At presentation, CT sensitivity was therefore 97.2%, whereas the sensitivity of initial rRT-PCR was only 83.3%.

Conclusion: rRT-PCR may produce initial false negative results. We suggest that patients with typical CT findings but negative rRT-PCR results should be isolated, and rRT-PCR should be repeated to avoid misdiagnosis.

Keywords: Coronavirus; Pneumonia; Severe Acute Respiratory Syndrome; Tomography; X-Ray Computed.

MeSH terms

  • Adult
  • Aged
  • Betacoronavirus / genetics*
  • COVID-19
  • COVID-19 Testing
  • COVID-19 Vaccines
  • Clinical Laboratory Techniques / methods
  • Coronavirus Infections / diagnosis*
  • Female
  • Humans
  • Male
  • Middle Aged
  • Pandemics
  • Pneumonia, Viral / diagnosis*
  • Real-Time Polymerase Chain Reaction
  • Retrospective Studies
  • SARS-CoV-2
  • Tomography, X-Ray Computed