- 期刊
B群鏈球菌與常見生殖道棲息菌在CMP^(TM) GBS TransCultSwab裝置中的消長情形
Growth of Group B Streptococcus and Common Genital Tract Colonizing Bacteria in CMP^(TM) GBS TransCultSwab Device
摘要
CMP^(TM) GBS TransCultSwab係針對B群鏈球菌（Group B Streptococcus，GBS，Streptococcus agalactiae，B群鏈球菌）檢驗檢體的採檢、輸送、增菌與輔助鑑別的一種裝置。此裝置為一個帶有兩個腔室的塑膠管，上層腔室含有特殊的培養液，有利於B群鏈球菌的生長，且能抑制非鏈球菌類細菌的生長。由於B群鏈球菌的生長會將培養液變為胡蘿蔔色，因此該培養液稱為胡蘿蔔培養液（carrot broth）。本研究旨在調查生殖道常見定植菌對該裝置中B群鏈球菌生長的影響。測試時，取出裝置下層腔室的棉拭，分別接種10^3 CFU的GBS與糞腸球菌（Enterococcus faecalis）以及10^6 CFU的大腸桿菌（Escherichia coli）、金黃色葡萄球菌（Staphylococcus aureus）、枯草芽孢桿菌（Bacillus subtilis）或白色念珠菌（Candida albicans），隨即將棉拭裝置與管子轉緊，接著輕經地壓斷上層腔室塑膠細管，讓carrot broth的液體流入下層腔室，與棉拭浸泡，混合均勻。接種後的裝置隨後在35℃或室溫下培養0、2.5、5.0或7.5小時。在每個時間點取出接種培養液的一部分，並接種於TSA培養基上，以塗抹法進行菌落數計數（Total viable counts），操作雙重複。結果指出隨著培養時間的延長，GBS與糞腸球菌的菌量隨著增加，在培養7.5小時後，兩者菌量分別增加約565倍及184倍，而金黃色葡萄球菌增長約44倍；枯草桿菌降低約99.1倍，而大腸桿菌及白色念珠菌則完全消失。至於在室溫培養則測試菌的菌量改變不大。基於上述的發現，吾等認為利用CMP^(TM) GBS TransCultSwab採檢產前生殖道檢體，在35℃培養的7.5小時內其所含的carrot broth可即時讓GBS增菌，並且降低其它定植菌的菌量，從而提高GBS分離率。此外，此新裝置若與微生物自動化接種系統如Kiestra InoqulA（BD公司，美國）或WASP（Copan公司，義大利）結合，將可大幅提升檢驗效率，有助於檢驗室縮短GBS檢驗週期與提升GBS檢出率，值得臨床醫師及檢驗人員的應用。
並列摘要
The CMP^(TM) GBS TransCultSwab with transport/enrichment medium is a device for collection and transport of samples for detection of Group B Streptococcus (GBS, Streptococcus agalactiae) as well as enrichment and preliminary identification of GBS. The device is a plastic tube with two chambers. The upper chamber contains special broth which favors the growth of GBS but is inhibitory for that of non-streptococcal bacteria. As the growth of GBS will turn the culture broth carrot color, the broth is referred to as carrot broth. This study was conducted to investigate the influence of common colonizing bacteria of the reproductive tract on the growth of GBS in the device. For the test, the cotton swab in the lower chamber of the device was removed and inoculated individually with 10^3 CFU of GBS, Enterococcus faecalis or 10^6 CFU of Escherichia coli, Staphylococcus aureus, Bacillus subtilis, or Candida albicans. The inoculated swab was returned to the tube, followed by breakin g the upper chamber, thus allowing the carrot broth to flow to the lower chamber and soak the cotton swab. The inoculated device was then incubated at 35℃ or room temperature for 0, 2.5, 5.0, or 7.5 hours. An aliquot of the inoculated broth was taken at each time point and plated on TSA for CFU determination. After 7.5 hours of incubation at 35℃ , we observed an increase in the CFU of GBS (565 fold), Enterococcus faecalis (184 fold), and Staphylococcus aureus (44 fold); a decrease in the CFU of Bacillus cereus (99.1 fold); and complete disappearance of both E. coli and Candida albicans. At room temperature, the amounts of GBS and the other five bacteria remained unchanged even after 7.5 hours of incubation. Based on these results, we conclude that the GBS TransCultSwab is an effective device for transport and enhancement of GBS. As it can be applied to automated microbial inoculation systems such as Kiestra InoqulA (BD) or WASP (Copan), it will greatly improve the efficiency and turnaround time for GBS detection and identification.