COVID-19: Chest X-ray and CT findings in a patient with marked dyspnea

date : 13.05.2020

*Alexandra Boyapati
**Tsvetomir Karagechev
**
***Orlin Zlatarski
*Kameliya Genova

*Department of Radiology, UMHATEM “N. I. Pirogov”, Sofia, Bulgariа **Department of Radiology, Acibadem City Clinic Tokuda Hospital, Sofia, Bulgaria ***Emergency Department, Acibadem City Clinic Tokuda Hospital, Sofia, Bulgaria

alexandraboyapati@gmail.com

Keywords: COVID-19, Viral pneumonia, CXR, Computed Tomography

Clinical history: A 54-year-old male patient presented to the Emergency Department with a 7-day history of fatigue, non-productive cough, fever up to 38C and an epidemiological history of contact with COVID-19. Medical history – hypertension. Laboratory tests on admission: CRP – 11,46 mg/dL, Leu – 7,69 G/L, Ly – 18,6%, ESR – 55mm/h, O2 saturation of 89%. IgG/IgM immunoassay was positive for both IgM and IgG.

Imaging findings:

Chest X-ray at initial presentation showed bilateral, fairly symmetric, patchy, multifocal, confluent opacities, especially in the middle and lower zones. The central regions were relatively spared (Figure 1). Chest NCCT showed bilateral, multifocal, ground-glass opacities (GGO) and a crazy-paving pattern (mixed GGO along with thickened interlobular septa). The imaging findings predominantly affected the dorsal lung segments with greater involvement of the right hemithorax. A large area of dense consolidation was identified in the right upper lobe with sharp delineation by the visceral pleura. Parenchymal consolidations were also identified in the basal segments of the right lung. Moreover, the diameters of the pulmonary vascular branches were greater than those of the accompanying bronchi. There were no signs of mediastinal lymphadenopathy or pleural effusion. (Figures 2-7)

Final diagnosis: The imaging pattern of parenchymal lung disease is in keeping with atypical pneumonia – viral pneumonia, caused by Coronavirus (SARS –CoV2) – COVID-19.

Discussion:

The SARS-CoV-2 disease tends to affect the distal airways and these patients most often present with symptoms of acute respiratory tract infection. Therefore, conventional radiography is considered the imaging method of first choice in the diagnostic process. In the early stages of the infection, CXR findings are mostly negative (1). As the disease progresses, radiographic worsening is observed with increased interstitial markings, increased density of the lung fields with diffusely disturbed GGOs and patchy confluent opacities. The interlobular septae in the pulmonary interstitium become prominent. Pulmonary consolidations are usually not seen until the later stages of infection. The imaging findings are typically peripheral in distribution, which corresponds affection of the distal airways. Computed tomography is a highly sensitive modality, which allows identification and assessment of lung anomalies even before the patients develop severe clinical symptoms of COVID-19 infection (3,4). According to a study from Wuhan University, China (2), CT imaging findings can be categorized in 5 stages – ultra-early stage, early stage, rapid progression stage, consolidation stage, dissipation stage. During the ultra-early stage of infection (patients without clinical manifestation, within 1-2 weeks after exposure to the virus), CT scans show single or diffuse GGOs, lung nodules surrounded by ground-glass opacities and consolidation with air-bronchogram. In the early stage (1-3 days after onset of clinical symptoms), CT imaging features include GGOs and interlobular septal thickening. Typical CT findings during the rapid progression stage (3-7 days after clinical manifestations) are larger areas of parenchymal consolidation with air-bronchograms, which decrease in size and density during the consolidation stage (7-14 days after the onset of clinical symptoms). In the final stage (dissipation stage, 2-3 weeks from the clinical symptoms) the pattern of chest CT abnormalities consists of patchy consolidations, strip-like opacities and bronchial wall thickening. The imaging findings in the presented case are typical for stage III (rapid progression stage) and show a good correlation with the time after the onset of the clinical symptoms – seven days. According to the WHO’s criteria, this case is classified as severe COVID-19 disease – saturation ≤93% and infiltration of more than 50% of the lung field.

Differential diagnosis:

Viral pneumonia with different etiology; Mycoplasma pneumonia, Chlamydia pneumonia; In patients without epidemiological risk factors, which present with relevant clinical symptoms, non-infectious diseases such as vasculitis and dermatomyositis should be included in the differential diagnosis.

Take home messages:

COVID-19 infection can be suspected with a reasonable degree of probability based on the chest X-Ray and CT findings. The severity of the involvement of parenchymal tissue can be simultaneously evaluated with the CT scan and shows good correlation with the clinical manifestation of the disease.

Bibliography:

1.Ng M, Lee EYP, Yang J, et al. Imaging profile of the COVID-19 infection: Radiologic findings and literature review. Radiology: Cardiothoracic Imaging 2020;2(1):e200034. Doi: 10.1148/ryct.2020200034. 2.A rapid advice guideline for the diagnosis and treatment of 2019 novel coronavirus (2019-nCoV) infected pneumonia (standard version) Ying-Hui Jin, Lin Cai... Zhongnan Hospital of Wuhan University Novel Coronavirus Management and Research Team, Evidence-Based Medicine Chapter of China International Exchange and Promotive Association for Medical and Health Care (CPAM) https://mmrjournal.biomedcentral.com/articles/10.1186/s40779-020-0233-6 3.Kim JY, Choe PG, Oh Y, et al. The first case of 2019 novel coronavirus pneumonia imported into Korea from Wuhan, China: implication for infection prevention and control measures; Korean Med Sci 2020; 35:e61 4.Pan Y, Guan H, Zhou S, et al. Initial CT findings and temporal changes in patients with the novel coronavirus pneumonia (2019-nCoV): a study of 6

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