极/超低出生体质量儿院内感染病原菌分布及临床特点分析

Distribution and clinical characteristics of nosocomial infection in very/extremely low birth weight infants

目的探讨极/超低出生体质量儿医院感染的发生情况及临床特征,为预防和控制医院感染提供依据。方法回顾性分析2017年1月1日至2018年12月31日首都医科大学附属北京妇产医院新生儿重症监护室发生院内感染的极/超低出生体质量儿的临床特点。结果120例极/超低出生体质量儿中发生医院内感染40例,感染部位主要为血液(57.7%),其次是呼吸道(21.1%)。检出的50种致病菌中革兰阳性球菌(Gram-positive bacteria,G^+)、革兰阴性菌(Gram-negative bacteria,G^-)及真菌占比分别为56%、18%及26%。前5位致病菌为近平滑念珠菌、表皮葡萄球菌、屎肠球菌、鲍曼不动杆菌、粪肠球菌。表皮葡萄球菌对复方新诺明、苯唑西林、青霉素全部耐药,对环丙沙星、左旋氧氟沙星及红霉素出现部分耐药;屎肠球菌对环丙沙星、氨卡西林、红霉素及青霉素等出现不同程度的耐药,这3种G^+球菌对万古霉素及利奈唑胺均敏感。鲍曼不动杆菌对头孢呋辛、头孢喹林及氨卡西林出现明显耐药,但对4代头孢、碳青霉烯类抗菌药物敏感。近平滑念珠菌则对氟康唑等抗真菌药普遍敏感。G^+、G^-及真菌感染患儿的胎龄、出生体质量、院内感染发生的时间差异无统计学意义,早期出现反应差、发热、血氧下降/呼吸暂停、腹胀等消化道症状、血小板减少、白细胞总数及分类异常、CRP及降钙素原增高的发生率比较,差异均无统计学意义。结论极/超低出生体质量儿是院内感染的易感人群,感染比例高,致病菌主要是凝固酶阴性的葡萄球菌、真菌及肠球菌,感染主要部位是血流感染和呼吸道感染,且G^+、G^-及真菌引起的院内感染早期没有特异性,应严格控制感染因素,采用针对性措施控制极/超低出生体质量儿院内感染发生。

Objective To investigate the status and clinical characteristics of nosocomial infection in very/extremely low birth weight infants,and to provide evidence for the prevention and control of nosocomial infection.Methods The clinical characteristics of very/extremely low birth weight infants with nosocomial infection in Neonatal Intensive Care Unit from January 1 st,2017 to December 31 st,2018 were retrospectively investigated.Results A total of 120 very/extremely low birth weight infants were enrolled in the study,of which 40 had nosocomial infections.Blood infection was the most common site of nosocomial infection(57.7%),followed by respiratory infection(21.1%).Among 50 isolated pathogens,28 strains of gram-positive bacteria(G^+)accounted for 56%,nine strains of gram-negative bacteria(G^-)accounted for 18%and 13 strains of fungi accounted for 26%.The top five pathogens were Candida near smooth,Staphylococcus epidermidis,Enterococcus faecium,Acinetobacter baumannii and Enterococcus faecalis.Resistance analysis showed that Staphylococcus epidermidis were all resistant to compound trimethoprim,oxacillin and penicillin,and partly resistant to ciprofloxacin,levofloxacin and erythromycin.Enterococcus faecalis showed no drug resistance.Enterococcus faecium showed different degrees of resistance to ciprofloxacin,amikacillin,erythromycin and penicillin.These three G^+were sensitive to vancomycin and linezolid.Acinetobacter baumannii were resistant to cefuroxime,cefaquilin and amkacillin,but sensitive to fourth generation cephalosporins and carbapenems.Smooth Candida were generally sensitive to fluconazole and other antifungal agents.There were no significant difference in gestational age,birth weight and time of nosocomial infection among infants with G^+,G^-and fungal nosocomial infections.A similar incidence of poor response,fever,hypoxia/apnea,abdominal distention and other digestive tract symptoms,thrombocytopenia,total white blood cell count and classification abnormalities,increased CRP and procalcitonin were found in infants with G^+,G^-and fungal nosocomial infections in the early stage.Conclusions Very/extremely low birth weight infants are susceptible to nosocomial infection.The main pathogens detected in the center are coagulase-negative staphylococcus,fungi and enterococcus.The main sites of nosocomial infection are blood and respiratory tract.There is no specificity in the early stage of nosocomial infection caused by G^+,G^-and fungi.Targeted measures should be adopted to prevent and control the occurrence of nosocomial infection in very/extremely low birth weight infants.