Alexander Sarah, Ison Catherine
Sexually Transmitted Bacteria Reference Laboratory, Health Protection Agency, Centre for Infections, Colindale Avenue, London NW9 5HT, UK.
J Med Microbiol. 2005 Sep;54(Pt 9):827-831. doi: 10.1099/jmm.0.46108-0.
Eight identification methods were evaluated against 100 isolates of Neisseria gonorrhoeae and 21 non-gonococcal Neisseria strains. The methods examined included four commercial biochemical kits, API NH, RapID NH, Gonochek II and Neisseria Preformed Enzyme Test (PET), three immunological kits, Phadebact Monoclonal GC test, GonoGen II and MicroTrak, and one in-house carbohydrate-utilization method, cystine trypticase agar (CTA) sugars. The percentage of isolates unambiguously identified as N. gonorrhoeae by each of the methods was as follows: API NH, 66 %; RapID NH, 64 %; GonoChek II, 66 %; Neisseria PET, 66 %; Phadebact Monoclonal GC OMNI test, 99 %; GonoGen II, 100 %; MicroTrak, 100 %; and CTA sugars, 96 %. The low sensitivity of the biochemical kits for the identification of N. gonorrhoeae was due to a lack of the enzyme proline iminopeptidase (Pip) in 34 % of the isolates examined. All the biochemical kits utilized the presence of this enzyme as a marker for N. gonorrhoeae. The Phadebact Monoclonal GC kit, GonoGen II, MicroTrak, CTA sugars and the API NH kit all exhibited high specificity, but non-gonococcal Neisseria were misidentified as N. gonorrhoeae using RapID NH (two strains), Gonochek II (11 strains) and Neisseria PET (11 strains). Whilst the isolates examined in this study may not be truly representative, they do indicate that N. gonorrhoeae isolates lacking the enzyme Pip can give anomalous results when using commercially available biochemical tests and that some non-pathogenic Neisseria species are still being misidentified using some biochemical kits. This further reinforces the recommendation that any dubious biochemical result should be confirmed with an immunological test.
针对100株淋病奈瑟菌分离株和21株非淋菌性奈瑟菌菌株，对8种鉴定方法进行了评估。所检测的方法包括4种商业生化试剂盒，即API NH、RapID NH、Gonochek II和奈瑟菌预形成酶试验（PET）；3种免疫试剂盒，即Phadebact单克隆GC试验、GonoGen II和MicroTrak；以及1种内部碳水化合物利用方法，即胱氨酸胰蛋白酶琼脂（CTA）糖试验。通过每种方法明确鉴定为淋病奈瑟菌的分离株百分比如下：API NH为66%；RapID NH为64%；GonoChek II为66%；奈瑟菌PET为66%；Phadebact单克隆GC全项试验为99%；GonoGen II为100%；MicroTrak为l00%；CTA糖试验为96%。生化试剂盒对淋病奈瑟菌鉴定的低敏感性是由于在所检测的分离株中有34%缺乏脯氨酸亚氨基肽酶（Pip）。所有生化试剂盒都利用该酶的存在作为淋病奈瑟菌的标志物。Phadebact单克隆GC试剂盒、GonoGen II、MicroTrak、CTA糖试验和API NH试剂盒均表现出高特异性，但使用RapID NH（2株）、Gonochek II（11株）和奈瑟菌PET（11株）时，非淋菌性奈瑟菌被误鉴定为淋病奈瑟菌。虽然本研究中检测的分离株可能并非真正具有代表性，但它们确实表明，缺乏Pip酶的淋病奈瑟菌分离株在使用市售生化试验时可能会得出异常结果，并且一些非致病性奈瑟菌物种仍会被某些生化试剂盒误鉴定。这进一步强化了以下建议，即任何可疑生化结果均应用免疫试验进行确认。
