轻型和重型甲型H1N1流行性感冒患者临床特征、病毒载量以及排毒时间分析比较

Analysis on clinical features, viral load and viral shedding period of patients with mild or severe H1N1 influenza A virus infection

目的 了解轻型和重型甲型H1N1流行性感冒（流感）患者的临床和实验室特征、病毒载量及排毒时间.方法 对深圳地区70例轻型和16例合并肺炎的重型甲型H1N1流感患者采用实时荧光定量PCR方法,检测其甲型H1N1流感病毒载量.比较年龄＜14岁和≥14岁患者,以及轻型无肺炎和重型合并肺炎患者的病毒载量和病毒清除时间的差异.统计学方法采用t检验或卡方检验.结果 甲型H1N1流感患者最常见的临床表现是发热、咳嗽和扁桃体肿大.重型患者咳嗽、呼吸困难比例和最高体温较轻型患者显著增高（x2=10.9、14.3,t=3.65,均P＜0.01）.重型患者WBC计数、ALT水平较轻型患者显著升高（t=3.2、2.4,均P＜0.05）.重型患者胸部影像学类似间质性肺炎,多为磨玻璃样影.＜14岁患者的病毒载量和病毒清除时间较≥14岁的显著升高[（4.86±1.23）lg比（4.17±0.89）lg,t=2.3,P＜0.05]或延长[（5.33±0.49）d比（3.63±0.28）d,t=3.4,P＜0.01],重型患者病毒载量和病毒清除时间较轻型患者显著升高[（6.36±1.44）lg比（4.35±0.99）lg,t=6.1,P＜0.01]或延长[（5.75±1.77）d比（4.24±1.96）d,t=3.2,P＜0.01）.结论 甲型H1N1流感患者年龄和病情严重程度与病毒载量和排毒时间存在显著相关性.

Objective To analyze clinical and laboratory features, viral load and viral shedding period of patients with mild or severe H1N1 influenza A infection. Methods Seventy mild cases and 16 severe cases with concurrent pneumonia were included from Shcnzhen area for analysis.Nasopharyngeal-swab specimens of patients were collected and viral load was detected by real-time quantitative polymerase chain reaction （PCR） assay during their hospitalization. The viral load and viral shedding period were compared between patients over 14 years old and less than 14 years old, and between 70 mild cases without pneumonia and 16 severe cases with pneumonia. The statistic analysis was performed using t test and chi square test. Results The most common symptoms and signs of the patients were fever, cough and enlargement of tonsils. However, the severe cases suffered more frequently from cough, dyspnea and high fever compared with the mild cases （x2 = 10. 9 and 14.3, respectively, t=3.65; both P〈0.01 ）. The levels of white blood cell （WBC） count and alanine arninotransferase （ALT） of severe patients were both significantly higher than those of mild patients（t= 3.2, 2.4,respectively; both P〈0.05）. The chest radiology of the severe cases showed interstitial pneumonia,mostly with ground glass image. The viral load of patients under 14 years was significantly higher than those over 14 years [（4.86± 1.23） lg vs （4. 17±0.89） lg; t=2.3, P〈0.05], and the viral shedding period of patients under 14 years was significantly longer than those over 14 years [（5.33±0. 49） d vs（3. 63±0.28） d; t=3.4, P〈0.01]. The severe patients also displayed significantly higher viral load and prolonged viral shedding period than the mild patients [（6. 36±1. 44） lg vs （4. 35±0.99） lg, t=6.1,P〈0.01; （5.75±1.77） d vs （4. 24±1. 96） d, t=3.2, P〈0.01]. Conclusion Age anddisease severity of patients with H1N1 influenza A infection are significantly associated with viral load and viral shedding period.