Performance of Low-Dose Chest CT Scan for Initial Triage of COVID-19
| Author | Hooman Bahrami-Motlagh | en |
| Author | Sahar Abbasi | en |
| Author | Maryam Haghighimorad | en |
| Author | Babak Salevatipour | en |
| Author | Ilad Alavi Darazam | en |
| Author | Morteza Sanei Taheri | en |
| Author | Farzad Esmaeili Tarki | en |
| Author | Seyed Sina Naghibi Irvani | en |
| Orcid | Hooman Bahrami-Motlagh [0000-0002-0593-8511] | en |
| Orcid | Sahar Abbasi [0000-0002-6144-3767] | en |
| Orcid | Maryam Haghighimorad [0000-0003-0086-9446] | en |
| Orcid | Babak Salevatipour [0000-0002-0304-2914] | en |
| Orcid | Ilad Alavi Darazam [0000-0002-4440-335X] | en |
| Orcid | Morteza Sanei Taheri [0000-0002-8881-9058] | en |
| Issued Date | 2020-10-31 | en |
| Abstract | Background: Chest computed tomography (CT) scan is frequently used for diagnosis of coronavirus disease 2019 (COVID-19), especially in regions with limited availability of reverse-transcription polymerase chain reaction test (RT-PCR) test. Low-dose CT of chest offers acceptable image quality with lower radiation dose, particularly important in younger patients. Objectives: We have designed the current study to evaluate the diagnostic efficacy of low-dose chest CT versus early RT-PCR results, for triage of COVID-19 patients. Patients and Methods: From February 20 to April 15, 2020, 163 patients including 100 males (61.3%) with the median age of 65 years (21 to 97), who underwent both RT-PCR and chest CT were registered in the study. Low-dose chest CT protocol was applied with parameters modified from the lung cancer screening protocol. The accuracy of low-dose chest CT for COVID-19 diagnosis was evaluated, considering first RT-PCR results as reference. Results: Of 163 patients, 89 cases (54.6%) were presented with positive initial RT-PCR result. Lymphocyte percentage and lymphocyte count were significantly lower in the positive RT-PCR group (15% versus 19%, and 0.98 vs. 1.3, respectively); while, erythrocyte sedimentation rate (ESR) was significantly higher (53 vs. 22). Positive chest CT findings were present in 133/163 cases (81.6%). The sensitivity, specificity, positive and negative predictive values (PPV and NPV) and accuracy of low-dose chest CT scan were 96.6% (95% confidence interval [CI], 90% - 99%), 36.5% (95% CI, 26% - 49%), 64.7% (95% CI, 56% - 73%), 90% (95% CI, 72% - 97%) and 69.3% (95% CI, 61% - 76%), respectively based on positive RT-PCR results. Conclusion: Low-dose chest CT scan provides both high sensitivity and negative predictive value in diagnosing COVID-19 compared to initial RT-PCR as the gold standard. It can be used as an alternate to standard-dose CT scan in areas with high prevalence of COVID-19 disease and limited availability of RT-PCR for early triage. | en |
| DOI | https://doi.org/10.5812/iranjradiol.104950 | en |
| Keyword | Novel Coronavirus 2019 | en |
| Keyword | COVID-19 | en |
| Keyword | Chest CT Scan | en |
| Keyword | Low-Dose Protocol | en |
| Publisher | Brieflands | en |
| Title | Performance of Low-Dose Chest CT Scan for Initial Triage of COVID-19 | en |
| Type | Research Article | en |