Rahdar Hossein Ali, Malekabad Ebadallah Shiri, Dadashi Ali-Reza, Takei Elahe, Keikha Masuod, Kazemian Hossein, Karami-Zarandi Morteza
Department of Social Medicine, Aja University of Medical Sciences, Tehran, Iran.
Department of Microbiology, School of Medicine, Iranshahr University of Medical Sciences, Iranshahr, Iran.
Ethiop J Health Sci. 2019 Nov;29(6):745-750. doi: 10.4314/ejhs.v29i6.11.
Klebsiella pneumoniae is a Gram-negative enteric bacterium that causes nosocomial infections; this bacterium has survived from harsh condition using biofilm formation in hospital equipment and cause severe infection. In the other hand, the emergence and extension of carbapenem resistance burden among K. pneumonia producing biofilm is the current concern of public health services. There are controversial findings about this subject. The aim of this study was to evaluate the correlation between biofilm formation and resistance to carbapenem among clinical isolates of K. pneumoniae.
A total of 160 K. pneumoniae isolates were collected from various infections of hospitalized patients. The Carba NP test and molecular methods were used for detection of carbapenem resistance isolates of K. pneumonia. Subsequently, the ability for biofilm production was performed from all isolates. Finally, Correlation of biofilm formation among carbapenem resistant isolates was calculated using χ2 and Fisher's exact tests.
Among K. pneumoniae isolates 42.5% have carbapenemase activity by Carba NP test, while carbapenemase genes were detected in 35.6% of isolates in amplification assay. Moreover, there are 52.5% (n= 84) of all isolates were formed a strong biofilm, while 38.1% (n= 61) and 9.3% (n= 15) of isolates were middle and weak biofilm producer, respectively. Among carbapenem resistant cases (n= 68), there are 77.9% (n= 53) and 22% (n= 15) of isolates were reported as strong and middle biofilm producer, respectively. We see a significant correlation was seen between biofilm formation ability and carbapenem resistant isolates (p-value < 0.00001).
The increase of carbapenem resistance burden in biofilm producing isolates of K. pneumoniae is considered as serious alert and the basic measures to combat this phenomenon is imperative.
肺炎克雷伯菌是一种革兰氏阴性肠道细菌，可引起医院感染；该细菌通过在医院设备中形成生物膜在恶劣条件下存活并导致严重感染。另一方面，产生物膜的肺炎克雷伯菌中碳青霉烯耐药负担的出现和扩大是公共卫生服务当前关注的问题。关于这个主题存在有争议的发现。本研究的目的是评估肺炎克雷伯菌临床分离株中生物膜形成与对碳青霉烯耐药之间的相关性。
从住院患者的各种感染中收集了总共160株肺炎克雷伯菌分离株。采用Carba NP试验和分子方法检测肺炎克雷伯菌的碳青霉烯耐药分离株。随后，对所有分离株进行生物膜产生能力检测。最后，使用χ2检验和Fisher精确检验计算碳青霉烯耐药分离株中生物膜形成的相关性。
在肺炎克雷伯菌分离株中，通过Carba NP试验有42.5%具有碳青霉烯酶活性，而在扩增试验中35.6%的分离株检测到碳青霉烯酶基因。此外，所有分离株中有52.5%（n = 84）形成强生物膜，而分别有38.1%（n = 61）和9.3%（n = 15）的分离株是中等和弱生物膜产生者。在碳青霉烯耐药病例（n = 68）中，分别有77.9%（n = 53）和22%（n = 15）的分离株被报告为强和中等生物膜产生者。我们发现生物膜形成能力与碳青霉烯耐药分离株之间存在显著相关性（p值<0.00001）。
产生物膜的肺炎克雷伯菌分离株中碳青霉烯耐药负担的增加被视为严重警示，应对这一现象的基本措施势在必行。
