儿童耐碳青霉烯类抗生素鲍曼不动杆菌感染32例临床及耐药性分析

目的 总结儿童耐碳青霉烯类抗生素鲍曼不动杆菌(CRAB)感染的临床特征及细菌耐药性,并探讨儿童CRAB感染的危险因素.方法 回顾性分析2004年1月1日-2010年12月31日温州医学院附属育英儿童医院收治的32例CRAB感染患儿的临床及细菌药敏资料,并对CRAB和碳青霉烯类抗生素敏感鲍曼不动杆菌(CSAB)感染患儿进行1∶2回顾性病例对照研究.结果 32例中男21例,女11例,年龄1 d～16岁(中位年龄43 d),其中≤28 d患儿14例(44%).诊断为医院获得性肺炎(HAP)28例(88%),创口感染4例(12%).主要的原发疾病为新生儿呼吸窘迫综合征(12例),先天性心脏病(5例)和开放性骨折(5例).32例中接受过外科手术10例(31%);入住ICU29例(91%);接受气管插管机械通气26例(81%),通气时间2～249 d(中位时间12 d);分离出CRAB前2周内使用过碳青霉烯类抗生素者17例(53%),使用β内酰胺类加酶抑制剂13例(41%),使用三代头孢菌素8例(25%).治愈16例(50%),好转12例(38%),未愈自动出院1例(3%),死亡3例(9%).自32例中共检出49株CRAB,占同期AB检出数的10.4%(49/472),其中40株(82%)分离自呼吸道,9株(18%)分离自开放性骨折创口,均呈多重耐药,其中13株(27%)为泛耐药.对氨苄两林/舒巴坦的耐药率为90%,对头孢菌素的耐药率均超过85%,对头孢哌酮/舒巴坦的耐药率最低(19%).Logistic回归分析显示,感染CRAB的独立危险因素为接受外科手术(OR=8.450)、气管插管机械通气＞10 d(OR=6.366)及检出前2周内使用碳青霉烯类抗生素(OR=7.084).结论 CRAB主要导致儿童HAP和开放性创口感染.CRAB呈现多重耐药甚至泛耐药.接受外科手术、气管插管机械通气＞10 d、检出CRAB前2周内使用碳青霉烯类抗生素是发病的独立危险因素.

Abstract：

Objective This study aimed to summarize the clinical characteristics and antimicrobial resistance of carbapenem-resistant Acinetobacter baumannii (CRAB) infections in children,identify its risk factors and to raise the level of diagnosis and treatment of this disease.Method The data of clinical and antimicrobial susceptibility of 32 cases of CRAB and 64 cases of carbapenem-susceptible Acinetobacter baumannii (CSAB) infections as control seen between January 1, 2004 and December 31, 2010 in Yuying Children's Hospital Affiliated to Wenzhou Medical College were analyzed retrospectively. Result Thirty-two cases of CRAB infections were identified, 21 were male and 11 female. The ages ranged from 1 day to 16 years (median age 43 days),among whom 14(44%) were aged ≤28 days; 28 cases (88%)were diagnosed as hospital-acquired pneumonia(HAP)and 4 cases(12%)had wound infection.The common primary diseases of the cases were neonatal respiratory distress syndrome(n=12,38%),followed by congenital heart disease(n=5,16%) and open fractures(n=5,16%).Before the isolation of CRAB, 10 cases (31%) had received major surgery;29 patients (91%) had stayed in ICUs,26 cases(81%)had received tracheal intubation and mechanical ventilation,the ventilation time was 2-249 days(median:12 days).Carbapenem was used in 17 cases(53%)previously,13(41%)had received β-lactam/β-lactamase inhibitor combinations, 8(25%)had used 3rd-generation cephalosporins within 2 weeks before the isolation of CRAB. Sixteen cases(50%)were cured, 12 cases(38%)were improved,parents of 1 case(3%)automatically gave up hospitalization without being cured and 3 cases(9%)died.Forty-nine CRAB strains were isolated from the 32 cases, accounting for 10.4% of AB isolation strains in the same period,in which 40 strains (82%)were isolated from sputum specimens and 9 strains(18%)from open wounds secretions.All 49 strains showed multidrug-resistance (MDR),of which 13 strains (27%)were pandrug-resistant(PDR) to the common antimicrobials.The rates of resistance to ampicillin-sulbactam and cephalosporins were 90% and more than 85%, respectively;while the rates of resistance to cefoperazone-sulbactam were 19% , the lowest among the tested agents.In multivariate analysis,receiving surgery(OR=8.450),tracheal intubation and mechanical ventilation for more than 10 days(OR=6.366)and previous use of carbapenems (OR=7.084)were independent risk factors for CRAB infections.Conclusion Nosocomial infections in children due to CRAB infections mainly cause HAP and open wound infection.Previous surgery,prolonged tracheal intubation and mechanical ventilation for more than 10 days and previous carbapenems therapy within 2 weeks before the isolation of CRAB were independent risk factors for CRAB infections. CRAB showed MDR or even PDR to the common antimicrobials, which made great difficulties in antibiotic choices.

Analysis of clinical characteristics and antimicrobial resistance of carbapenem-resistant Acinetobacter baumannti infections in children

Objective This study aimed to summarize the clinical characteristics and antimicrobial resistance of carbapenem-resistant Acinetobacter baumannii (CRAB) infections in children,identify its risk factors and to raise the level of diagnosis and treatment of this disease.Method The data of clinical and antimicrobial susceptibility of 32 cases of CRAB and 64 cases of carbapenem-susceptible Acinetobacter baumannii (CSAB) infections as control seen between January 1, 2004 and December 31, 2010 in Yuying Children's Hospital Affiliated to Wenzhou Medical College were analyzed retrospectively. Result Thirty-two cases of CRAB infections were identified, 21 were male and 11 female. The ages ranged from 1 day to 16 years (median age 43 days),among whom 14(44%) were aged ≤28 days; 28 cases (88%)were diagnosed as hospital-acquired pneumonia(HAP)and 4 cases(12%)had wound infection.The common primary diseases of the cases were neonatal respiratory distress syndrome(n=12,38%),followed by congenital heart disease(n=5,16%) and open fractures(n=5,16%).Before the isolation of CRAB, 10 cases (31%) had received major surgery;29 patients (91%) had stayed in ICUs,26 cases(81%)had received tracheal intubation and mechanical ventilation,the ventilation time was 2-249 days(median:12 days).Carbapenem was used in 17 cases(53%)previously,13(41%)had received β-lactam/β-lactamase inhibitor combinations, 8(25%)had used 3rd-generation cephalosporins within 2 weeks before the isolation of CRAB. Sixteen cases(50%)were cured, 12 cases(38%)were improved,parents of 1 case(3%)automatically gave up hospitalization without being cured and 3 cases(9%)died.Forty-nine CRAB strains were isolated from the 32 cases, accounting for 10.4% of AB isolation strains in the same period,in which 40 strains (82%)were isolated from sputum specimens and 9 strains(18%)from open wounds secretions.All 49 strains showed multidrug-resistance (MDR),of which 13 strains (27%)were pandrug-resistant(PDR) to the common antimicrobials.The rates of resistance to ampicillin-sulbactam and cephalosporins were 90% and more than 85%, respectively;while the rates of resistance to cefoperazone-sulbactam were 19% , the lowest among the tested agents.In multivariate analysis,receiving surgery(OR=8.450),tracheal intubation and mechanical ventilation for more than 10 days(OR=6.366)and previous use of carbapenems (OR=7.084)were independent risk factors for CRAB infections.Conclusion Nosocomial infections in children due to CRAB infections mainly cause HAP and open wound infection.Previous surgery,prolonged tracheal intubation and mechanical ventilation for more than 10 days and previous carbapenems therapy within 2 weeks before the isolation of CRAB were independent risk factors for CRAB infections. CRAB showed MDR or even PDR to the common antimicrobials, which made great difficulties in antibiotic choices.