人感染H7N9禽流行性感冒17例患者的临床特征和救治分析

Clinical characteristics and treatment of 17 patients with avian influenza A H7N9 virus infection

目的了解人感染H7N9禽流行性感冒（流感）重症病例的临床特征和危险因素，提高对重症病例诊治的认识。方法对广州市第八人民医院2014年1月至5月确诊的17例人感染H7N9禽流感患者的临床资料，包括基础疾病、禽类接触史、人院时病情严重程度、临床表现、实验室检查、影像学特征、并发症、治疗及转归等进行回顾性分析。计量资料采用t检验，计数资料采用y。检验（或Fisher确切概率法）；非正态数据采用Mann-WhitneyU检验。结果17例患者年龄4～88岁，平均53岁。存活11例，死亡6例。其中有11例存在基础疾病，合并两种以上基础疾病者6例。14例为重症病例。存活组患者氧合指数明显高于死亡组[（196．4土100．3）mmHg（1mmHg=0．133kPa）比（78．3±27．9）mmHg，t=3．523，P=0．004]，入院时急性生理与慢性健康评分Ⅱ（APACHElI）死亡组患者评分明显高于存活组（28．8士4．6比15．4±7．6，t=3．955，P=0．001）。入院检查所有重症患者均有不同程度的淋巴细胞及CD4’T淋巴细胞计数减少，存活组患者CD4’T淋巴细胞计数明显高于死亡组（t=2．378，P=0．031）。住院治疗过程中共有6例患者痰（肺泡灌洗液）培养病原学结果阳性，其中3例培养出鲍曼不动杆菌、白念珠菌、耐甲氧西林金黄色葡萄球菌（MRSA）、肺炎克雷伯菌、耐甲氧西林溶血葡萄球菌（MRSH）等多种病原体。17例患者均接受抗病毒治疗。14例重症患者入住ICU，均需机械通气治疗，其中7例患者予无创辅助通气，7例患者需有创通气支持；3例重度急性呼吸窘迫综合征（ARDs）患者予俯卧位通气治疗后氧合指数明显改善。结论高龄、有基础疾病是H7N9感染病例发展为重症的主要危险因素，重症病例主要表现为呼吸衰竭和免疫功能损害，容易继发细菌感染、感染性休克和多器官功能障碍综合征。多数病例需要ICU的综合救治，机械通气是主要救治措施，其中俯卧位通气可明显改善重症ARDS患者的氧合。

Objective To investigate the clinical characteristics and risk factors of patients with avian influenza A H7N9 virus severe infection, and to improve cognition of diagnosis and treatment for severe cases. Methods Data were collected and analyzed retrospectively from 17 patients with confirmed avian influenza A H7N9 virus infection admitted to Guangzhou Eighth Peoplers Hospital between January and May 2014, including underlying diseases, exposure history, illness severity on admission, clinical manifestations, laboratory examinations, imaging features, complications, treatment, the period of hospitalization and outcomes. Univariate analysis was performed using chi-square tests （or Fisher% exact tests） for binary outcomes and student t-tests for normally distributed outcomes or Mann-Whitney U test for non-normally distributed outcomes. Results The average age of 17 patients were 53（4-88） years old. Among them, 11 patients survived and 6 patients died. Eleven cases had underlying diseases and 6 cases had two or more than two underlying diseases. Fourteen cases were severe infection. Oxygenation index were significantly higher in the survive group compared with the death group （[-196.4± 100.3] mmHgvs [-78.34-27.9] mmHg, t=3.523,P=0.004）. Average acute physiology and chronic health evaluation II （APACHE II ） score in the survive group was 15.4± 7.6, which was significantly lower than the death group （28.8±4.6, t=3. 955,P= 0. 001）. The lymphocytes and CD4＋ T lymphocyte count decreased in all severe cases, but CD4＋ T lymphocyte count in the survive group was significantly higher than the death group （t= 2. 378, P= 0. 031）. Sputum （bronchoalveolar lavage fluid） cultures from 6 patients were positive, including 3 of Acinetobacter baumanii, Albicans saccharomyces, methicillin resistant Staphylococcus aureus （MRSA）, Klebsiella pneumoniae and methicillin resistant Staphylococcus haemolyticus （MRSH）. Antiviral therapy was administered for all the 17 patients. Fourteen severe cases were admitted to intensive care units and required mechanical ventilation, of which 7 patients with noninvasive ventilation and 7 patients with invasive ventilation. Three cases With severe acute respiratory distress syndrome （ARDS） were treated with the prone positioning during mechanical ventilation, and oxygenation index improved significantly after treatment. Conclusions Elderly and underlying diseases are the major risk factors for patients with severe H7N9 infection. Most severe cases show respiratory failure and immunosuppression, leading to secondary bacterial infections, septic shock and multiple organ dysfunction syndrome. Most severe cases require intensive care. Mechanical ventilation is the main treatment measures, and prone positioning can significantly improve oxygenation in patients with severe ARDS in short time.