Fig. 4

Two representative cases to illustrate the application of the nomogram. A A 40-year-old male patient complained of fever for 4 days (score ≈ 80). He had travelled to Huangshi, a city in Wuhan Province, China a week before the onset (score ≈ 100). His laboratory tests indicated leukocytopenia (1.99*10^9/L, score ≈ 92). His chest CT showed patchy ground glass opacities with vascular enlargement and reticular changes on bilateral lower lobes (left lower lobe involvement: score ≈ 83; multifocal: score ≈85). Lesions were located both central and peripheral (score ≈ 80). No mediastinal lymphadenopathy was observed (score ≈ 80). Slight pleural thickening was observed (score ≈ 85). Total estimated score reached around 687, indicating > 99.8% probability to be a COVID-19 case. He was later confirmed by RT-PCR. B A 60-year-old female patient complained of fever for 3 days (score ≈ 80). She claimed no contact or exposure history (score ≈ 60). Her WBC count is slightly elevated (10.52*10^9/L, score ≈ 60). Her chest CT showed unifocal (score ≈ 68) large patchy ground glass opacities with consolidation only involving the right upper lobe (score ≈ 63), but with both central and peripheral distribution (score ≈ 80). Mediastinal lymphadenopathy was observed in mediastinal window (score ≈ 60). No pleural thickening (score ≈ 70). Total estimated score reached around 541, indicating < 0.2% probability to be a COVID-19 case. She was radiologically suspected as COVID-19, but the diagnosis of COVID-19 was ruled out by 2 consecutively negative RT-PCR test results. She was finally diagnosed with respiratory syncytial virus infection