Disease course and temporal changes of chest X-ray findings in COVID-19 positive patients at Phayao hospital

Abstract

Background & Purpose: Since the outbreak of coronavirus disease 2019 (COVID-19) infection is progressing and worsening in various parts of the world. COVID-19 infection usually manifests clinically as pneumonia. In Thailand, portable chest X-ray (CXR) was the most commonly used modality for identification and follow up of lung abnormalities in COVID-19 positive patients. This study aims to describe the CXR findings and temporal radiographic changes in patients with confirmed COVID-19 throughout the admission period.

Material and Methods: A retrospective descriptive study of a laboratory confirmed COVID-19 patients by

using RT-PCR who were admitted in Phayao hospital from April 10, 2021 to May 15, 2021. Patients'

demographics, baseline CXR and serial follow up CXR were reviewed. A severity index was determined for each lung image. The lung finding scores were summed to produce the total severity score (TTS).

Results: A total of 58 patients (30 (51.7%) males and 28 (48.3%) females). Age of the patients ranged from 2 to 79 years old with mean age was 35.52 ± 16.80 years. A total of 241 chest x-rays were obtained for the 58 patients. Thirty-one in 58 patients (53.4%) had abnormal CXR findings at certain points of the disease course. There were 172 baseline CXR and serial CXR of 31 patients with abnormalities were analyzed to see temporal lung change. The most common finding on CXR was peripheral ground glass opacities (GGO) affecting the lower lung lobes. In the course of illness, the GGO progressed to diffuse consolidations affecting the middle and lower lung lobes around 1-8 days with peaking at day 1-4 after initial CXR. The severity of findings at CXR peaked at 4-7 days from initial CXR. The consolidations regressed and reticulations were developed over day 9 from initial CXR, indicating a healing phase. Bilateral middle lung zones and bilateral lower lung zones were the last areas of recovered.

Conclusion:  This study showed that CXR was a good monitoring of COVID-19 radiologic manifestations and its scoring system provided a good method to predict the disease severity.