Yu Wen-Liang, Ko Wen-Chien, Cheng Kuo-Chen, Lee Hsin-Chun, Ke Der-Shin, Lee Ching-Chien, Fung Chang-Phone, Chuang Yin-Ching
Department of Intensive Care Medicine, Chi-Mei Medical Center, Yungkang City, Tainan, Taiwan.
Clin Infect Dis. 2006 May 15;42(10):1351-8. doi: 10.1086/503420. Epub 2006 Apr 11.
The association of the magA gene with the hypermucoviscosity phenotype relevant to the pathogenesis of Klebsiella pneumoniae liver abscess has been reported in Taiwan. Similarly, the rmpA gene, known as a positive regulator of extracapsular polysaccharide synthesis that confers a mucoid phenotype, may be another candidate gene causing hypermucoviscosity. However, the association of rmpA with K. pneumoniae clinical syndromes is unreported. We aimed to investigate the clinical correlation between rmpA and primary Klebsiella abscess, focusing on sites other than the liver.
From July 2003 through December 2004, a total of 151 K. pneumoniae isolates recovered from 151 patients with bacteremia were collected from 2 large medical centers in southern Taiwan. Clinical data were collected from medical records. The genes rmpA and magA were amplified by polymerase chain reaction using specific primers.
The prevalences of hypermucoviscosity, rmpA, and magA were 38%, 48%, and 17%, respectively. As determined by statistical multivariate analysis, strains carrying rmpA were significantly associated with the hypermucoviscosity phenotype, and there was a significant correlation with purulent tissue infections, such as liver abscess and lung, neck, psoas muscle, or other focal abscess.
Our data support a statistical correlation between the rmpA gene and virulence in terms of abscess formation for these hypermucoviscous K. pneumoniae strains. Hypermucoviscosity associated with rmpA, together with a thorough physical examination, may be helpful as a guide to carry out appropriate diagnostic tests on patients with an initially unknown source of K. pneumoniae bacteremia, particularly when looking for the occurrence of an underlying abscess.
在台湾，已报道magA基因与肺炎克雷伯菌肝脓肿发病机制相关的高黏液性表型有关。同样，rmpA基因作为一种赋予黏液样表型的荚膜外多糖合成的正调控因子，可能是导致高黏液性的另一个候选基因。然而，rmpA与肺炎克雷伯菌临床综合征之间的关联尚未见报道。我们旨在研究rmpA与原发性克雷伯菌脓肿之间的临床相关性，重点关注肝脏以外的部位。
2003年7月至2004年12月，从台湾南部的2家大型医疗中心收集了151例菌血症患者分离出的151株肺炎克雷伯菌。从病历中收集临床数据。使用特异性引物通过聚合酶链反应扩增rmpA和magA基因。
高黏液性、rmpA和magA的患病率分别为38%、48%和17%。经统计学多变量分析确定，携带rmpA的菌株与高黏液性表型显著相关，且与化脓性组织感染显著相关，如肝脓肿、肺脓肿、颈部脓肿、腰大肌脓肿或其他局灶性脓肿。
我们的数据支持这些高黏液性肺炎克雷伯菌菌株的rmpA基因与脓肿形成的毒力之间存在统计学相关性。与rmpA相关的高黏液性，连同全面的体格检查，可能有助于指导对最初病因不明的肺炎克雷伯菌菌血症患者进行适当的诊断检查，特别是在寻找潜在脓肿的发生时。
