Chest CT Outperformed Lab Testing in Diagnosing Coronavirus Disease

A recent study found chest Computed Tomography (CT) outperformed lab testing in the diagnosis of the coronavirus disease COVID-19.

And, these researchers at Tongji Hospital in Wuhan, China, found that the sensitivity of CT for COVID-19 infection was 97 percent compared to RT-PCR sensitivity of 71 percent.

Published on February 26, 2020, this study’s results are based on 1,014 Chinese patient evaluations between January 6 and February 6, 2020.

The results showed that 601 patients (59%) had positive RT-PCR results, and 888 (88%) had positive chest CT scans.

Of these, 48 percent were considered as highly likely cases, with 33 percent as probable cases.

By analysis of serial RT-PCR assays and CT scans, the interval between the initial negative to positive RT-PCR results was 4 to 8 days.

A Chest CT is a routine imaging tool for pneumonia diagnosis and is fast and relatively easy to perform.

"About 81% of the patients with negative RT-PCR results but positive chest CT scans were re-classified as highly likely or probable cases with COVID-19, by the comprehensive analysis of clinical symptoms, typical CT manifestations, and dynamic CT follow-ups," the authors wrote.

They concluded that CT should be used as the primary screening tool for COVID-19 disease.

This is an important study in the absence of specific therapeutic drugs for COVID-19 disease, as it is essential to detect the disease at an early stage and immediately isolate an infected patient from the healthy population.

According to the latest guidelines published by the Chinese government, the diagnosis of COVID-19 disease must be confirmed by reverse-transcription polymerase chain reaction (RT-PCR) or gene sequencing for respiratory or blood specimens, as the key indicator for hospitalization.

However, with limitations of sample collection and transportation, as well as kit performance, the total positive rate of RT-PCR for throat swab samples has been reported to be about 30 to 60 percent at an initial presentation.

In the current public health emergency, the low sensitivity of RT-PCR implies that a large number of COVID-19 patients won’t be identified quickly and may not receive appropriate treatment.

In addition, given the highly contagious nature of the virus, they carry a risk of infecting a larger population.

Coronavirus diagnostic testing news published by Coronavirus Today.