探讨急性髓系白血病（AML）患者诱导缓解期间发生医院下呼吸感染的病原菌分布、危险因素及影像学特点。

回顾性分析2010年1月至2014年12月本科新入并住院治疗的126例急性髓系白血病患者，对发生医院下呼吸道感染病例进行单因素检验和多因素的非条件Logistic回归分析，并对肺部感染的影像学特点进行分析。

126例AML患者中发生医院下呼吸道感染102例，感染率为80.9%，感染病死率为3.2%。单因素分析初步筛选出年龄> 60岁、白细胞数≤ 2 × 10⁹/L及> 10 × 10⁹/L、血红蛋白≤ 60 g/L、淋巴细胞计数、白蛋白≤ 30 g/L、化疗方案（IA方案）、住院时间> 30 d以及PICC置管为可能危险因素。多因素Logistic回归分析，最终确定血红蛋白≤ 60 g/L、白蛋白≤ 30 g/L以及化疗方案（IA方案）为急性髓系白血病患者下呼吸道感染的危险因素。CT影像显示，102例患者中两肺都有病变的62例、右肺病变的23例、左肺病变的17例。大片或斑片状阴影37例，占所有肺部感染36.3%；结节病变共22例，占所有肺部感染21.6%；条索、片状及磨玻璃影19例，占所有肺部感染病例的18.6%；结节及斑片影共17例（占16.7%）；结节、实变及空洞影共7例（占6.8%）。5例真菌培养阳性患者均表现为结节影合并空洞影，而细菌感染者仅2例（2/26），表现为结节影合并空洞影，有统计学意义（χ² = 20.44，P = 0.00）。

AML患者诱导缓解期发生医院下呼吸道感染率高，血红蛋白≤ 60 g/L、白蛋白≤ 30 g/L以及化疗方案（IA方案）为急性髓系白血病患者下呼吸道感染的危险因素。急性髓系白血病患者下呼吸道感染肺部影像学表现多样，但结节影合并空洞影提示真菌感染可能性大。

To analyze the pathogenic bacteria distribution, risk factors and imaging features for nosocomial infections in patients with acute myelogenous leukemia (AML) at the induced remission stage.

The data of 126 patients with AML hospitalized in our hospital from January 2010 to December 2014 were analyzed, restrospectively. The clinical data for cases with lower respiratory infection were analyzed by the single factor test and the multi-factor unconditioned Logistic regression analysis. While the imaging characteristics of pulmonary infection were analyzed.

There were 102 cases with lower respiratory tract infection among the 126 patients with AML, the infection rate was 80.9% and the infection mortality rate was 3.2%. Age > 60 years old, white blood cell count ≤ 2 × 10⁹/L and > 10 × 10⁹/L, The level of hemoglobin ≤ 60 g/L, lymphocytes count, albumin ≤ 30 g/L, chemotherapy (IA program), length of hospital stay > 30 days and PICC catheter were all the possible risk factors by single factor analysis. The level of hemoglobin ≤ 60 g/L, albumin ≤ 30 g/L and chemotherapy (IA program) were all the risk factors of respiratory infections for patients with AML by multivariate Logistic regression analysis. There were 62 cases with both lung lesions, 23 cases with right lung disorders, 17 cases with left lung lesions. There were 37 cases with Large or patchy shadows, accounting for 36.3% of all lung infection; 22 cases with nodular lesions, accounting for 21.6% of all lung infection; 19 cases had cord and ground glass flake, accounting for 18.6%; 17 cases (16.7%) had nodules and patchy total; 7 cases (6.8%) had nodules, consolidation and empty shadow. 5 cases with fungal culture-positive showed nodules merged with empty shadow, while only 2 cases (2/26) of bacterial infection showed nodules empty shadow, with significant differences (χ² = 20.44, P = 0.00).

For patients with AML remission induction, the hospital infection rate was high. Hemoglobin ≤ 60 g/L, albumin ≤ 30 g/L and chemotherapy (IA program ) were all risk factors of respiratory infection for patients with AML. The lung imaging of acute myeloid leukemia in patients with lower respiratory tract infection was diversity, nodular shadows merged with empty shadow suggests fungal infection.