AHMEDABAD: When a city-based general physician developed Covid-19 symptoms in late May, he underwent an RT-PCR test. To his relief, the result was negative. But fellow doctors suggested he undergo high-resolution computed tomography (HRCT) thorax screening, and his lungs showed patches of ‘opaque ground glass’ typically associated with Covid-19. A repeat blood test showed he was Covid-19 positive.
The physician was among 125-plus city-based medical practitioners who underwent free diagnosis offered by Dr Amit Gupta, a city-based radiologist at his imaging centre for the past 10 days. This was during the time when Covid-19 testing mandated government approval and hospitalization. Out of total screening, 73 tested positive, said Dr Gupta.
“I started the screening as a large number of medical practitioners started getting infected by Covid-19. It was a small gesture of gratitude towards the frontline Covid-19 warriors,” said Dr Gupta. “About 30 doctors underwent RT-PCR after getting diagnosed of Covid-19 through CT scan and all tested positive.” Interestingly, it is not just Dr Gupta who swears by the accuracy of CT scans – several critical care specialists and radiologists have started Covid-19 screening based on ‘CT severity score’ which is internationally accepted practice during the pandemic.
“Accuracy of CT scans is higher than RT-PCR. Moreover, RT-PCR is a yes or no kind of test whereas CT scans give the exact picture of severity. The score is given based on patches found in all five lobes of our two lungs. If the score is up to 12, it’s mild. If it’s above 18, it’s severe. The course of treatment is decided based on the score,” said Dr Priyank Mehta, a city-based radiologist, who has conducted over 70 scans for Covid-19 so far. “There are also almost nil chances of false taste – something that we have seen in RT-PCR.”
Scanning an opportunity
When the RT-PCR tests were under red tape, the alternative methods were widely used by the medical practitioners to quickly assess the patient’s health conditions before important surgeries or medical procedures. Experts point at CT scan, chest X-ray and tests such as ferritin levels and c-reactive protein (CRP) levels in blood as some of the important markers of Covid.
Dr Maharshi Desai, critical care specialist on the state government’s expert committee on Covid-19 response, said that CT scan and other methods are surely used widely by the experts to assess the health indicators of the patient. “But RT-PCR remains the gold standard. Even when a patient’s lungs show opaque patches in CT scan, he or she would be under suspect category and would be advised by the RTPCR test to confirm the person as a Covid-19 positive.”
Dr Jayesh Sheth, a citybased genetic scientist, said that ferritin and CRP tests should be a norm to assess the patients on whether they have infection. “They are much quicker and reliable to point at the body’s response to the infection. It can save precious time and in some cases a patient’s life,” he said.