肠球菌溶血素的表型及基因型检测

目的 探讨影响肠球菌溶血素检测的因素,提高肠球菌溶血素检测的准确性. 方法 分别用兔血、人血、绵羊血检测48株肠球菌的溶血素表型,比较其检出率;用PCR检测溶血性肠球菌的溶血素cylA基因片段;对129株肠球菌同时进行溶血素表型(兔血检测)及基因型的检测,比较其检出率的差异. 结果 兔血、人血的肠球菌溶血素检出率分别为41.7%和35.4%,而绵羊血的肠球菌溶血素检出率为0(P＜0.01);14.06%cylA基因阳性菌株未出现相应表型, 6.78%溶血表型阳性菌株PCR未检测到溶血素cylA基因. 结论 兔血及人血对肠球菌溶血素较敏感,绵羊血对肠球菌溶血素不敏感;溶血素表型及基因型的检测不完全相符;对肠球菌溶血素同时进行表型及基因型的检测,能提高肠球菌溶血素检测的准确性.

Detection of Enterococci Hemolysin in Phenotype and Genotype

Objective To investigate factors affecting the detection of Enterococci hemolysin in order to enhance the accuracy of hemolysin detection. Methods Hemolytic phenotype were detected by rabbit, human and sheep blood plate disk respectively in 48 strain Enterococci, and their incidence of hemolytic circle were compared. Hemolysin genotype was detected by PCR of cylA gene. Incidence of 129 Enterococci hemolytic phenotype and genotype were compared. Results Incidence of hemolysin using rabbit and human erythrocytes were 41.7% and 35.4% respectively, compared with 0% using sheep erythrocytes(P<0.01). Hemolytic phenotype were not detected in 14.06%cylA gene positive strains, and cylA genes were not detected in 6.78% exhibiting hemolytic phenotype. Conclusion Rabbit erythrocytes and human erythrocytes are more sensitive to Enterococci hemolytic than sheep erythrocytes. Discrepancy existed between the phenotype and genotype of Enterococci. Phenotype and genotype of Enterococci should be examined simultaneously to enhance the detection accuracy.