Lazareva A V, Katosova L K, Kryzhanovskaya O A, Ponomarenko O A, Karaseva O V, Gorelik A L, Mayanskiy N A
Antibiot Khimioter. 2014;59(7-8):8-15.
Nosocomial infections and their rational antibiotic treatment represent a major challenge for the healthcare nowadays. In this context, gramnegative bacteria including Pseudomonas aeruginosa, Acinetobacter baumanii and Enterobacteriaceae spp. are etiologically important and characterized by a significant level of antibiotic resistance. To examine dynamics of the respiratory tract colonization by hospital flora, tracheal aspirates obtained at three time points from 69 children with severe craniocerebral trauma during their stay in ICU were analysed. Colonization was observed on the 4th day of the ICU stay with predomination of K. pneumoniae (45%) and A. baumanii (27-37%). P. aeruginosa was detected after the 8th day of the ICU stay with the isolation rate of 33%. Substantial proportions of P. aeruginosa (61%), A. baumanii (78%) and K. pneumoniae (25%) were resistant to carbapenems. In 65 carbapemen resistant isolates, the presence of carbapenemases was examined using PCRs. OXA-48 carbapenemase was detected in 11 out of 14 (78%) K. pneumoniae isolates. Among the A. baumanii isolates, 30/31 (97%) carried OXA-40 and 1/31 (3%) had OXA-23 carbapenemases. None of the examined A. baumanii and K. pneumoniae isolates produced metallo-betalactamases (MBL). In contrast, all 20 carbapenem resistant P. aeruginosa isolates produced a MBL, and in 12 out of 20 (60%) of theme VIM-2 was detected. Thus, gramnegative nosocomial microflora rapidly colonizes ICU patients and has a high level of resistance to antibiotics, including carbapenems.
医院感染及其合理的抗生素治疗是当今医疗保健面临的一项重大挑战。在这种背景下,包括铜绿假单胞菌、鲍曼不动杆菌和肠杆菌科细菌在内的革兰氏阴性菌在病因学上具有重要意义,且具有显著水平的抗生素耐药性。为了研究医院菌群在呼吸道的定植动态,对69例重症颅脑外伤患儿在重症监护病房(ICU)住院期间三个时间点采集的气管吸出物进行了分析。在入住ICU的第4天观察到定植,以肺炎克雷伯菌(45%)和鲍曼不动杆菌(27%-37%)为主。入住ICU第8天后检测到铜绿假单胞菌,分离率为33%。相当比例的铜绿假单胞菌(61%)、鲍曼不动杆菌(78%)和肺炎克雷伯菌(25%)对碳青霉烯类耐药。在65株碳青霉烯类耐药菌株中,使用聚合酶链反应(PCR)检测碳青霉烯酶的存在。在14株肺炎克雷伯菌分离株中的11株(78%)检测到OXA-48碳青霉烯酶。在鲍曼不动杆菌分离株中,30/31(97%)携带OXA-40,1/31(3%)具有OXA-23碳青霉烯酶。所检测的鲍曼不动杆菌和肺炎克雷伯菌分离株均未产生金属β-内酰胺酶(MBL)。相比之下,所有20株碳青霉烯类耐药铜绿假单胞菌分离株均产生MBL,其中12/20(60%)检测到VIM-2。因此,革兰氏阴性医院菌群迅速定植于ICU患者,并对包括碳青霉烯类在内的抗生素具有高度耐药性。