A Characteristic Chest Radiographic Pattern in the Setting of COVID-19 Pandemic

Smith, David L.; Grenier, John-Paul; Batte, Catherine; Spieler, Bradley

BACKGROUND: Compared with chest CT, there is a relative paucity of data regarding the role of the chest radiograph (CXR) in the diagnosis of COVID-19. PURPOSE: To determine the utility of CXR in aiding clinical diagnosis of COVID-19, utilizing RT-PCR as the standard of comparison. MATERIALS AND METHODS: A retrospective study was performed of persons under investigation (PUIs) for COVID-19 presenting to our institution during the exponential growth phase of the COVID-19 outbreak in New Orleans, USA (March 13 – 25, 2020). 376 in-hospital CXR exams for 366 individual patients were reviewed along with concurrent RT-PCR tests. Two experienced radiologists categorized each CXR as characteristic, nonspecific, or negative in appearance for COVID-19, utilizing well-documented COVID-19 imaging patterns. CXR categorization was compared against RT-PCR results to determine the utility of CXR in diagnosing COVID-19. RESULTS: There were 178/366 male (49%) and 188/366 female (51%) patients with a mean age of 52.7 years (range 17 to 98 years). 37/376 CXR exams (10%) exhibited the characteristic COVID-19 appearance; 215/376 (57%) exhibited the nonspecific appearance; and 124/376 (33%) were considered negative for a pulmonary abnormality. Of the 376 RT-PCR tests evaluated, 200/376 (53%) were positive and 176/376 (47%) were negative. RT-PCR tests took an average of 2.5 ± 0.7 days to result. Sensitivity and specificity for correctly identifying COVID-19 with a characteristic CXR pattern were 15.5% (31/200) and 96.6% (170/176), with PPV and NPV 83.8% (31/37) and 50.1% (170/339), respectively. CONCLUSION: The presence of patchy and/or confluent, bandlike ground glass opacity or consolidation in a peripheral and mid-to-lower lung zone distribution on a chest radiograph obtained in the setting of pandemic COVID-19 is highly suggestive of SARS-CoV-2 infection and should be used in conjunction with clinical judgement to make a diagnosis.