Clinical study on patients with severe influenza A (H1N1)

Abstract

Objective To describe basic characteristics, clinical features and outcomes of patients with severe irfluenza A(H1N1), and provide reference for clinical prevention and treatment. Methods 36 patients with severe influeza A(H1N1) at 6 hospitals of Hangzhou between June and December 2009 were observed, among which 27 cases were serious influenza A(H1N1) patients, 9 cases were criticalinfluenza A(H1N1) patients. Results Patients were young (median, 24.0 [range, 2.5-73.0]ages).36 cases(100.0%) had fever and pharyngeal hyperemia, 35 cases (97.2%) had cough, 27 cases(75.0%) were with weak and 16 cases (44.4%)had muscle soreness. 27 cases (75.0%) had pneumonia and 5 cases(13.9%) were with respiratory failure. On admission, the median fever days,APACHE Ⅱ score, PaO2/FiO2, creatinine levels, platelet, creatine kinase levels in patients with critical influenza A (H1N1)were 8.5(3-17)days, (14±5), 157(130-337)mm Hg(1 mm Hg=0.133 kPa), 93(66-298)μmol/L, (113±41)×109/L, 335(64-2038)U/L, respectively, but in patients with serious influenza A(H1N1) were 6(2-13) days,(10±3), 258(210-557)mm Hg, 79(25-107)μmol/L, (164±57)×109/L, 116.0(27-451)U/L, respectively. There were significant differences in all parameters above between two groups (t=2.104,2.790,-2.558,2.359,-2.478,2.782, respectively, P＜0.05). 32cases received antiviral therapy with osehamivir. 13 cases received glucocorticoid.2cases received mechanical ventilation for severe acute respiratory distress syndrome and refractory hypoxemia. No patients died. Conchusions Severe illness of influenza A (H1N1) occurs mainly in young indiv iduals, the main clinical manifestations are fever, respiratory and systemic symptom. Patients with critical influenza A(H1N1) are often companied with most of multiorgans damage. APACHE Ⅱ can be used to identify critical patients in early stage. Key words: Influenza A virus,H1N1 subtype; Severe; Clinical features