Diagnostic performance of thorax CT in mildly symptomatic COVID-19 patients: The importance of atypical CT findings

OBJECTIVE: Computed tomography of the thorax (Thorax CT) is frequently used to diagnose viral pneumonia in moderate to severe COVID-19 patients, but its diagnostic performance in mildly symptomatic COVID-19 patients is still unclear. Assessing the diagnostic performance of thorax CT in mildly symptomatic COVID-19 patients was the purpose of our study.
METHODS: Mildly symptomatic and clinically stable, suspected COVID-19 patients scanned with Thorax CTs between March 11, 2020, and April 13, 2020, were included in this study. The sensitivity, specificity, positive and negative likelihood ratios, positive and negative predictive values, and the respective accuracies were calculated for diagnostic purposes.
RESULTS: Among the 1119 patients enrolled in our study, abnormal thorax CT scans were 527 out of which 363/527 (68.9%) had typical CT features for COVID-19. According to analysis of typical COVID findings, sensitivity, specificity, positive predictive values, negative predictive value, and the accuracy of Thorax CTs with were 51.45%, 86.07%, 78.24%, 64.55%, and 68.99%, respectively. When typical CT findings and atypical CT findings were combined for the statistical analysis, the sensitivity, specificity, and accuracy observed 68.84%, 74%, and 71.49%.
CONCLUSION: Diagnosing pneumonia can be challenging in mildly symptomatic COVID-19 patients since the Reverse Transcription Polymerase Chain Reaction test results, when compared with symptoms are not always evident. According to our study, thorax CT sensitivity was higher when atypical COVID-19 CT findings were included compared to those with typical COVID-19 CT findings alone. Our study which included the largest number of patients among all other similar studies indicates that not only typical but also atypical CT findings should be considered for an accured diagnosis of COVID-19 pneumonia.

Hafif semptomlu Covid19 hastalarýnda Toraks BT'nin tanýsal performansý: Atipik BT bulgularýnýn önemi

Amaç: Toraks bilgisayarlý tomografi (BT), orta ila þiddetli Covid19 hastalarýnda viral pnömoniyi teþhis etmek için sýklýkla kullanýlýr, ancak hafif semptomlu Covid19 hastalarýndaki tanýsal performansý halen net deðildir. Hafif semptomlu Covid19 hastalarýnda Toraks BT tanýsal performansýný deðerlendirmek, çalýþmamýzýn amacý idi.
Yöntemler: 11 Mart 2020 ile 13 Nisan 2020 tarihleri arasýnda toraks BT ile taranan, hafif semptomlu ve klinik olarak stabil, þüpheli Covid19 hastalarý bu çalýþmaya dahil edildi. Taný amaçlý sensitivite, spesifite, pozitif ve negatif olabilirlik oranlarý, pozitif ve negatif prediktif deðerleri ve ilgili doðruluklar hesaplandý.
Bulgular: Çalýþmamýza katýlan 1119 hasta arasýnda, anormal Toraks BT taramalarý 527 idi ve bunlarýn 363 / 527'sinde (%68,9) Covid19 için tipik BT özellikleri vardý. Tipik Covid19 bulgularýnýnanalizine göre; Toraks BT’lerin sensitivite, spesifite, pozitif prediktif deðer, negatif prediktif deðer ve doðruluðu sýrasýyla %51.45, %86.07, %78.24, %64.55 ve %68.99 idi. Tipik BT bulgularý ve atipik BT bulgularý istatistiksel analiz için birleþtirildiðinde, sensitivite, spesifite ve doðruluk % 68,84, %74 ve %71,49 olarak gözlendi.
Sonuç: Hafif semptomlu Covid19 hastalarýnda pnömoni tanýsý koymak zor olabilir çünkü Revers-Transkriptaz Polimeraz Zincir Reaksiyonu (RT-PCR) test sonuçlarý, semptomlarla karþýlaþtýrýldýðýnda her zaman net deðildir. Çalýþmamýza göre atipik Covid19 BT bulgularý dahil edildiðinde toraks BT duyarlýlýðý, tek baþýna tipik Covid19 BT bulgularýna göre daha yüksekti. Diðer tüm benzer çalýþmalar arasýnda en fazla sayýda hastayý içeren çalýþmamýz, Covid19 pnömonisinin doðru tanýsý için yalnýzca tipik deðil, ayný zamanda atipik BT bulgularýnýn da dikkate alýnmasý gerektiðini göstermektedir. (NCI-2020-0458.R1)