对奥谱托欣耐药肺炎链球菌的鉴定

Identification of Streptococcus pneumoniae resistant to optochin

目的对奥谱托欣耐药的肺炎链球菌和奥谱托欣敏感的其他α溶血性链球菌进行准确的鉴定。方法采用奥谱托欣敏感试验、胆汁溶解试验、乳胶凝集试验及生化鉴定试验进行鉴定。结果630株肺炎链球菌中有两株对奥谱托欣具有抗药性,占0.3%。31株对奥谱托欣具有敏感性的α溶血性链球菌包括13株缓症链球菌、6株口腔链球菌、6株孪生球菌、3株少酸链球菌、2株中间型链球菌、1株星座链球菌。对奥谱托欣敏感的α溶血性链球菌,其抑菌环直径绝大部分在14～17mm范围内,而肺炎链球菌对奥谱托欣的抑菌环直径绝大部分都在20mm以上。对奥谱托欣敏感的α溶血性链球菌对苯唑西林大都呈高度耐药(93.5%),而肺炎链球菌大都敏感(94.0%)。结论胆汁溶解试验和乳胶凝集试验鉴定肺炎链球菌的特异性高,试验结果可靠。APIStrept鉴定试条和VITEK·TWOGPC鉴定卡可用于耐奥谱托欣肺炎链球菌的鉴定。

Objective Correctly identify Streptococcus pneumoniae resistant to optochin and other alpha hemolytic streptococcus susceptible to optochin. Methods Optochin susceptibility test, bile resolution test, latex agglutination test as well as some biochemical methods （VITEKCCA-GPI identifying cards, APIStrept identifying bar, VITEK TWO-GPC identifying cards） were applied. Results It was observed that 2 strains （ 0. 3% ） of Streptococcus pneumoniae out of 630 were resistant to optochin and 31strains of Streptococci, classfied as alpha hemolytic streptococci, susceptible to optochin, including 13 of S. mitis, 6 of S. oralis, 6 of S. twin, 3 of S. acidominimus, 2 of S. intermedius and 1 of S. constellatus. The inhibition zone of these alpha hemolytic streptococci susceptible sensitive to optochin was within the range of 14-17ram in diameter, in not 20 mm or more than 20 mm, compared with the inhibition zone of most strains of S. pneumoniae. Most of these alpha hemolytic streptococci （93.5%） susceptible to optochin showed highly resistance to benzoxazolecillin, to which most Streptococci （94%） showed sensitivity . Conclusion S. pneumoniae can be effectively identified by bile resolution test and latex agglutination test because of its high specificity with credible test results. API-Strept identifying bar and VITEK TWO-GPC identifying cards can be applied to identify S. pneumoniae resistant to optochin.