Table 2.

 Laboratory and chest radiographic findings of 442 patients with 2009 pandemic influenza A (H1N1)

Variable	Overall patients (n = 442)	Pediatric patients (n = 387)	Adult patients (n = 55)	P value*
Leukocyte count
Leukocytosis (White cell count >10 × 109 cells/l), no./total no. (%)	20/216 (9·3)	18/184 (9·8)	2/32 (6·3)	0·745
Leukopenia (White cell count <3 × 109 cells/l), no./total no. (%)	9/216 (4·2)	7/184 (3·8)	2/32 (6·3)	0·625
Lymphocyte count				0·010
<3·0 (×109 cells/l) in children, no./total no. of children (%)	–	170/182 (93·4)	–
<1·5 (×109 cells/l) in adults, no./total no. of children (%)	–	–	24/31 (77·4)
Platelet count
Thrombocytosis (>450 × 109 cells/l), no./total no. (%)	1/215 (0·5)	1/183 (0·5)	0/32 (0)	>0·99
Thrombocytopenia (<149 × 109 cells/l), no./total no. (%)	38/215 (17·7)	27/183 (14·5)	9/32 (24·4)	0·074
C‐reactive protein >5 mg/l (reference value <5 mg/l), no./total no. (%)	139/208 (66·8)	116/183 (63·4)	23/25 (92)	0·003
Creatine kinase >130 U/l (reference value 15–130 U/l), no./total no. (%)	31/144 (21·5)	28/130 (21·5)	3/14 (21·4)	>0·99
Lactic dehydrogenase >225 U/l (reference value 135–225 U/l), no./total no. (%)	55/139 (39·5)	50/126 (39·6)	5/13 (23·1)	>0·99
Aspartate aminotransferase >40 U/l (reference value >40 U/l), no./total no. (%)	26/181 (14·4)	24/168 (14·3)	2/13 (15·4)	>0·99
Alanine aminotransferase >40 U/l (reference value >40 U/l), no./total no. (%)	18/182 (9·9)	14/164 (8·5)	4/18 (22·2)	0·084
Abnormalities on chest radiograph, no./total no.(%)	19/227 (8·4)	18/190 (9·5)	1/37 (2·7)	0·326
Features of abnormalities appeared on chest radiography, no./total no. with abnormalities (%)
Lung infiltration	9/19 (47·4)	9/18 (50)	–	–
Lung consolidation	7/19 (36·8)	7/18 (38·9)	–	–
Lung consolidation with pleural effusion	3/19 (15·8)	2/18 (11·1)	1/1 (100)	–

*Comparison between pediatric and adult patients.