Chest CT Scans As An Alternative To Test Kits To Diagnose COVID-19
With the coronavirus continuing to explode globally, many health care systems have been pushed to their limits attempting to care for all the seriously ill patients flooding their facilities. Compounding the problem is a shortage of critically needed test kits. Even when test kits are available, the results can take days to get back to physicians, at times delaying treatment as well as efforts to prevent the spread of the disease.
Although routine chest X-rays are usually sufficient in patients presenting with respiratory distress, computed tomography (CT) scans are often used in hospital settings for patients who present with more severe symptoms, as they are more sensitive than plain chest X-rays in distinguishing some aspects of lung disease.
Doctors in China turned to CT scans to make medical decisions about patients as an alternative to the test kits, as early diagnosis of COVID-19 was absolutely crucial,both for treatment and control of the disease. The doctors discovered a peculiar “ground glass’ pattern seen in the patients’ lungs in the CT scans that correlated well with the diagnosis of COVID-19, which was later confirmedwith the coronavirus test kits.
The Chinese physicians published a study in the Febuary26th issue of the journal Radiology detailing their findings in 1014 coronavirus patients who had pneumonia and concluded that chest CT has a “high sensitivity for diagnosis of COVID-19. Chest CT may be considered as a primary tool for the current COVID-19 detection in epidemic areas.”
Radiologists in the United States have expressed concern over the use of CT scans as a COVID-19 diagnostic tool, and urge radiologists to use caution. The American College of Radiology is reluctant to endorse CT scans as a diagnostic tool even though they admit that “…studies suggest that chest CT in particular may be positive in the setting of a negative test.”
Jeffrey Kane, a radiologist from the Department of Radiology, University of Wisconsin-Madison School of Medicine and Public Health, looked at CT scan data coming from China and noted that the findings on CT scans from patients with COVID-19 “are similar to those reported for SARS-CoV (11–13) and MERS-CoV(14,15), not surprising as the responsible viruses are also coronaviruses.” He also went on to state that bilateral ground-glass opacities should prompt radiologists to consider COVID-19 as a possible diagnosis.
While chest CT scans are not 100 percent accurate in pinpointing the presence of coronavirus in patients, with the continued availability of test kits still in short supply, physicians should consider using CTs to presumptively diagnose COVID-19, as early diagnosis can mean life–saving treatment for the patient and can also help to prevent the spread of disease by the early identification of contacts.
The author Venu Madhav Chennupati has been working in public health in India and is a final semester masters student in epidemiology at Harvard University. You can reach him at firstname.lastname@example.org