An 83-year-old female patient, presented with fever (38C), dry cough and asthenia for four days. She denied dyspnoea, chest pain, and gastrointestinal symptoms. She lived with her daughter. Laboratory studies revealed elevated serum ferritin (401 ng/mL; normal range 12 ng/mL - 300 ng/mL), slightly increased C-reactive protein (CRP, 7.58 mg/L; normal range <5.0 mg/L). The patient was hospitalised for further care.
Later, her 59-years-old daughter presented with fever (38.6C), dry cough, myalgia, headache. The patient was a tobacco cigarette smoker.
The mother’s non-contrast chest CT (Figs. 1a-f) demonstrated multifocal bilateral patchy ground-glass opacities with a predominantly lower and peripheral distribution. Superimposed on the ground-glass opacities a linear pattern with multiple small irregular lines was visible, consistent with crazy-paving pattern and diffuse bronchial wall thickening. No pleural effusion was found.
The daughter’s non-contrast chest CT (Figs. 2a-d) also demonstrated multifocal bilateral patchy ground-glass opacities with a predominantly lower and peripheral distribution and thickness of interlobular septa. In addition, CT images show bilateral alveolar consolidation in the lower and back parts of both lungs. Apical-predominant centrilobular emphysema was also evident.
Coronavirus disease-19 (COVID-19) is a disease caused by severe respiratory acute syndrome – coronavirus – 2 (SARS-CoV-2). It was initially reported in Wuhan, China, in December 2019, and is currently spreading worldwide [1,2]. The World Health Organization (WHO) stated that COVID-19 was a global health emergency on January 30th, 2020, and classified it as a pandemic on March 11th, 2020 .
SARS-CoV-2 is the seventh known coronavirus able to infect humans. Two other remarkable examples include severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS) [3-5].
The majority of patients with lower respiratory tract infections caused by COVID-19 presents with cough, fever and other non-specific symptomatology including dyspnoea, myalgia, headache and fatigue [3,4]. Some patients may also present early gastrointestinal symptoms, including vomiting, nausea, and diarrhoea, which preceded respiratory symptoms . About 20% of cases are severe, and the fatality rate is approximately 3% [1,3].
Real-time polymerase chain reaction (RT-PCR) is the current standard diagnostic method used to detect viral nucleotides from specimens obtained by nasopharyngeal swab, oropharyngeal swab, bronchoalveolar lavage, or tracheal aspirate [4,7]. Nevertheless, this method sensitivity is as low as 60-71% for detecting SARS-CoV-2, which can probably be attributed to the low viral load present in test samples .
By contrast, chest CT has revealed about 56-98% sensitivity in detecting COVID-19 even at initial presentation and can be useful in correcting false negatives acquired from RT-PCR during initial stages of infection [1,7].
During the early course of infection, main lung abnormalities include peripheral focal or multifocal ground-glass opacities affecting both lungs in approximately 50%–75% of patients [1-3]. As the progression of the disease, crazy paving and consolidation become the major CT findings, peaking around 9–13 days of disease. Then, it’s usually followed by a gradual clearing at near 1 month and beyond [1-3]. Pleural effusions and mediastinal lymphadenopathy are usually absent in COVID-19 patients .
Finally, it is important to point out that chest CT is more sensitive than chest X-ray for the detection of ground-glass opacities .
Thoracic imaging has a crucial role in the evaluation of patients suspected of COVID-19. Prompt recognition of imaging patterns based on the infection time course is essential for not only understanding the natural history of infection but also for helping to predict patient evolution and possible complication development .
The hallmark in the clinical diagnosis of COVID-19 infection includes focal or multifocal ground-glass opacities, crazy paving, and consolidation, with peripheral predominance.
Written patient consent for this case was waived by the Editorial Board. Patient data may have been modified to ensure patient anonymity.
 Kanne J, Little B, Chung J, et al (2020): Essentials for Radiologists on COVID-19: An Update—Radiology Scientific Expert Panel. Radiology. (PMID: 32105562)
 Ming-Yen NG, Elaine YP L, Jin Y, et al (2020): Imaging Profile of the COVID-19 Infection: Radiologic Findings and Literature Review. Radiology.
 Bernheim A, Mei X, Huang M, et al (2020): Chest CT Findings in Coronavirus Disease-19 (COVID-10): Relationship to Duration of Infection. Radiology. (PMID: 32077789)
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