目的: 探讨难治性肺炎（RMPP）患儿感染病原学特征及免疫球蛋白、C-反应蛋白（CRP）、白细胞（WBC）计数及降钙素原（PCT）等指标的临床价值。方法: 回顾性分析我院2019年1月―2021年3月收治的213例RMPP患儿及87例普通肺炎（GMPP）患儿临床资料。采集两组患儿外周血检测免疫球蛋白、CRP、WBC、PCT水平,并采集RMPP患儿支气管肺泡灌洗液（BALF）行细菌培养及药敏试验。以受试者工作特征曲线（ROC曲线）分析免疫球蛋白、CRP、WBC、PCT水平对RMPP鉴别诊断价值。结果: 213例RMPP患儿共检出158株病原菌,98株革兰阴性菌、60株革兰阳性菌。革兰阴性菌以肺炎克雷伯菌（29株）为主,革兰阳性菌以肺炎链球菌（31株）及金黄色葡萄球菌（24株）为主。药敏结果表明,肺炎克雷伯菌对亚胺培南、厄他培南、哌拉西林/他唑巴坦、妥布霉素、阿米卡星敏感;肺炎链球菌对头孢曲松、头孢噻肟、美罗培南、厄他培南、万古霉素、利奈唑胺、氯霉素、莫西沙星、左氧氟沙星敏感,金黄色葡萄球菌对庆大霉素、万古霉素、喹奴普丁/达福普汀、利奈唑胺、替加环素、莫西沙星、利福平敏感。两组患儿IgA、WBC水平比较无差异;RMPP组患儿IgG、IgM、CRP、PCT水平高于GMPP组患儿。ROC曲线显示,IgG、IgM、CRP、PCT对RMPP具有一定鉴别诊断价值（AUC=0.770、0.778、0.824、0.806,P<0.001）,且四项联合（AUC=0.902,P<0.001）鉴别诊断价值较高。结论: RMPP患儿感染病原菌主要为肺炎克雷伯菌、肺炎链球菌、金黄色葡萄球菌,经验性治疗时需覆盖以上病原体,并尽早检测病原学,疗效欠佳时需考虑耐药情况,并及时依据药敏结果予以目标性治疗。其IgG、IgM、CRP、PCT水平明显高于GMPP患儿,而RMPP不会对WBC造成较大影响,联合检测IgG、IgM、CRP、PCT可用于RMPP鉴别诊断。

Objective To investigate the etiological characteristics of infection and the expression significance of immunoglobulin, C-reactive protein (CRP), white blood cell count (WBC) and procalcitonin (PCT) in children with refractory pneumonia (RMPP). Methods The clinical data of 213 children with RMPP and 87 children with general pneumonia (GMPP) admitted from January 2019 to March 2021 were retrospectively analyzed. Peripheral blood of two groups of children was collected to detect the levels of immunoglobulin, CRP, WBC, and PCT, bronchoalveolar lavage fluid (BALF) of RMPP children was collected for pathogen culture and drug sensitivity test. The receiver operating characteristic (ROC) curve was used to analyze the value of immunoglobulin, CRP, WBC, and PCT in the differential diagnosis of RMPP. Results A total of 158 strains of pathogens were detected in 13 children with RMPP, including 98 strains of Gram-negative bacteria and 60 strains of Gram-positive bacteria. The Gram-negative bacteria were mainly Klebsiella pneumoniae (29 strains), while the Gram-positive bacteria were mainly Streptococcus pneumoniae (31 strains) and Staphylococcus aureus (24 strains). The results showed that Klebsiella pneumoniae was sensitive to imipenem, ertapenem, piperacillin/tazobactam, tobramycin and amikacin. Streptococcus pneumoniae was sensitive to ceftriaxone, cefotaxime, meropenem, ertabenem, vancomycin, Linezolid, chloramphenicol, moxifloxacin, levofloxacin, while Staphylococcus aureus was sensitive to gentamicin, vancomycin, quinuprtin/Dafoputine, linezolid, tegacycline, moxifloxacin, and rifampicin. There was no difference in the levels of IgA and WBC between the two groups; The levels of IgG, IgM, CRP, and PCT in the RMPP group were higher than those in the GMPP group. The ROC curve shows that IgG, IgM, CRP, and PCT have a certain differential diagnosis value for RMPP (AUC=0.770, 0.778, 0.824, 0.806, P<0.001), and the combination of the four (AUC=0.902, P<0.001) has a differential diagnosis value Higher. Conclusion The pathogenic bacterias of children with RMPP are mainly Klebsiella pneumoniae, Streptococcus pneumoniae and Staphylococcus aureus. The above pathogenic bacterias should be covered during empirical treatment, and the pathogen should be detected as soon as possible. If the curative effect is not good, drug resistance should be considered . And promptly give targeted treatment based on the results of drug sensitivity. The IgG, IgM, CRP and PCT level apparently higher than GMPP group, and RMPP will not have a significant impact on WBC. Combined detection of IgG, IgM, CRP, and PCT can be used for the differential diagnosis of RMPP.