Punsalang A, Migneault P C, Nolte F S
J Clin Microbiol. 1986 Dec;24(6):1104-6. doi: 10.1128/jcm.24.6.1104-1106.1986.
Commercial latex agglutination tests (LATs) for the simultaneous detection of clumping factor and protein A are gaining increased acceptance as a means of identifying Staphylococcus aureus. We evaluated two LATs (Accu-Staph; Carr-Scarborough, Decatur, Ga.; Staphaurex; Wellcome, Dartford, England) with particular emphasis on their ability to correctly identify oxacillin-resistant S. aureus. We tested 59 oxacillin-resistant S. aureus, 136 oxacillin-susceptible S. aureus, and 92 coagulase-negative staphylococcal strains with the two LATs and with thermonuclease, slide clumping factor, tube coagulase, and protein A hemagglutination tests. Clumping factor and protein A were present in 96.9 and 82.1% of our S. aureus strains, respectively. Accu-Staph correctly identified 92.8% and Staphaurex correctly identified 91.3% of S. aureus strains. No significant difference in LAT positivity rates, presence of clumping factor, or presence of protein A was found between oxacillin-resistant and -susceptible S. aureus. Overall, there were 31 false-negative LATs for 20 S. aureus strains, 14 with Accu-Staph and 17 with Staphaurex. Ninety-five percent of these strains possessed either clumping factor or protein A or both when these factors were determined independently. There were five false-positive LATs for four strains of coagulase-negative staphylococci (three Staphylococcus epidermidis and one Staphylococcus warneri), four with Accu-Staph and one with Staphaurex. Clumping factor was present in one S. warneri strain. Thus, the specificities of Accu-Staph, Staphaurex, and the clumping factor test were 95.6, 98.9, and 98.9%, respectively. Our results indicated that LATs identify oxacillin-resistant and -susceptible S. aureus equally well; however, they offer no greater sensitivity or specificity than the clumping factor test for identification of S. aureus.
用于同时检测凝聚因子和蛋白A的商用乳胶凝集试验（LAT）作为鉴定金黄色葡萄球菌的一种方法正越来越被广泛接受。我们评估了两种LAT（Accu-Staph；Carr-Scarborough公司，佐治亚州迪凯特市；Staphaurex；英国惠康公司，达特福德），特别着重于它们正确鉴定耐苯唑西林金黄色葡萄球菌的能力。我们用这两种LAT以及热核酸酶、玻片凝聚因子、试管凝固酶和蛋白A血凝试验检测了59株耐苯唑西林金黄色葡萄球菌、136株苯唑西林敏感金黄色葡萄球菌和92株凝固酶阴性葡萄球菌菌株。我们的金黄色葡萄球菌菌株中分别有96.9%和82.1%存在凝聚因子和蛋白A。Accu-Staph正确鉴定了92.8%的金黄色葡萄球菌菌株，Staphaurex正确鉴定了91.3%的金黄色葡萄球菌菌株。耐苯唑西林和苯唑西林敏感的金黄色葡萄球菌在LAT阳性率、凝聚因子的存在或蛋白A的存在方面未发现显著差异。总体而言，20株金黄色葡萄球菌菌株有31次LAT假阴性，Accu-Staph有14次，Staphaurex有17次。当独立检测这些因子时，这些菌株中有95%拥有凝聚因子或蛋白A或两者都有。4株凝固酶阴性葡萄球菌（3株表皮葡萄球菌和1株沃氏葡萄球菌）有5次LAT假阳性，Accu-Staph有4次，Staphaurex有1次。1株沃氏葡萄球菌菌株存在凝聚因子。因此，Accu-Staph、Staphaurex和凝聚因子试验的特异性分别为95.6%、98.9%和98.9%。我们的结果表明，LAT对耐苯唑西林和苯唑西林敏感的金黄色葡萄球菌的鉴定效果相同；然而，在鉴定金黄色葡萄球菌方面，它们的敏感性和特异性并不比凝聚因子试验更高。
