Normal CXR findings were significantly more frequent in patients with viral infection compared to bacterial infections (30% vs. 9%; p = 0.03). Multilobar infiltrates and pleural effusion on CXR were observed less often among subjects with viral infection (Tables 11, 12 and 13).Table 11Radiological findings for adult patients Viral Bacterial Mixed No pathogen p-value a (n = 40) (n = 36) (n = 6) (n = 100) Viral vs. bacterial Viral vs. mixed Viral vs. no pathogen X-ray, (n)3326581 Unilobar infiltrate, n (%)9 (27.3)5 (19.2)0 (0.0)14 (17.3)0.480.470.23 Multilobar infiltrates, n (%)6 (18.2)10 (38.5)2 (40.0)30 (37.0)0.090.560.05 Interstitial infiltrates, n (%)3 (9.1)7 (26.9)1 (20.0)17 (21.0)0.140.890.13 Pleural effusion, n (%)5 (15.2)11 (42.3)0 (0.0)24 (29.6)0.020.950.11 Normal, n (%)8 (24.2)2 (7.7)1 (20.0)14 (17.3)0.181.000.40Computer tomography, (n)2329571 Unilobar infiltrate, n (%)5 (21.7)4 (13.8)0 (0.0)7 (9.9)0.700.690.26 Multilobar infiltrates, n (%)11 (47.8)16 (55.2)4 (80.0)32 (45.1)0.600.420.82 Ground glass opacity, n (%)4 (17.4)6 (20.7)2 (40.0)29 (40.8)1.000.570.04 Pleural effusion, n (%)5 (21.7)13 (44.8)1 (20.0)25 (35.2)0.091.000.23 Normal, n (%)2 (8.7)0 (0.0)0 (0.0)0 (0.0)0.381.000.12 n number. Multiple findings were counted individually aMantel-Haenszel chi square test or Fisher exact test were used Table 12Radiological findings for pediatric patients Viral Bacterial Mixed No pathogen p-value a (n = 40) (n = 6) (n = 5) (n = 21) Viral vs. bacterial Viral vs. mixed Viral vs. no pathogen X-ray, (n)286516 Unilobar infiltrate, n (%)6 (21.4)0 (0.0)1 (20.0)2 (12.5)0.561.000.76 Multilobar infiltrates, n (%)6 (21.4)2 (33.3)4 (80.0)6 (37.5)0.880.040.42 Interstitial infiltrates, n (%)2 (7.1)1 (16.7)1 (20.0)2 (12.5)0.910.800.93 Pleural effusion, n (%)4 (14.3)2 (33.3)1 (20.0)2 (12.5)0.561.001.00 Normal, n (%)10 (35.7)1 (16.7)0 (0.0)3 (18.8)0.700.280.40Computer tomography, (n)5123 Unilobar infiltrate, n (%)2 (40.0)0 (0.0)0 (0.0)0 (0.0)1.000.950.71 Multilobar infiltrates, n (%)2 (40.0)1 (100.0)2 (100.0)3 (100.0)1.000.570.36 Ground glass opacity, n (%)0 (0.0)0 (0.0)1 (50.0)0 (0.0)n/a0.57n/a Pleural effusion, n (%)2 (40.0)1 (100.0)1 (50.0)2 (66.7)1.001.001.00 Normal, n (%)1 (20.0)0 (0.0)0 (0.0)0 (0.0)1.001.001.00 n number. Multiple findings were counted individually aMantel-Haenszel chi square test or Fisher exact test were used Table 13Radiological findings for all patients Viral Bacterial Mixed No pathogen p-value a (n = 80) (n = 42) (n = 11) (n = 121) Viral vs. bacterial Viral vs. mixed Viral vs. no pathogen X-ray, (n)61321097 Unilobar infiltrate, n (%)15 (24.6)5 (15.6)1 (10.0)16 (16.5)0.320.570.21 Multilobar infiltrates, n (%)12 (19.7)12 (37.5)6 (60.0)36 (37.1)0.060.030.02 Interstitial infiltrates, n (%)5 (8.2)8 (25.0)2 (20.0)19 (19.6)0.060.510.05 Pleural effusion, n (%)9 (14.8)13 (40.6)1 (10.0)26 (26.8)0.011.000.08 Normal, n (%)18 (29.5)3 (9.4)1 (10.0)17 (17.5)0.030.370.08Computer tomography, (n)2830774 Unilobar infiltrate, n (%)7 (25.0)4 (13.3)0 (0.0)7 (9.5)0.260.350.10 Multilobar infiltrates, n (%)13 (46.4)17 (56.7)6 (85.7)35 (47.3)0.440.140.94 Ground glass opacity, n (%)4 (14.3)6 (20.0)3 (42.9)29 (39.2)0.820.250.02 Pleural effusion, n (%)7 (25.0)14 (46.7)2 (28.6)27 (36.5)0.091.000.28 n number. Multiple findings were counted individually aMantel-Haenszel chi square test or Fisher exact test were used