Howe R A, Wootton M, Walsh T R, Bennett P M, MacGowan A P
Bristol Centre for Antimicrobial Research and Evaluation, Southmead Health Services NHS Trust and University of Bristol, Department of Microbiology, Southmead Hospital, Bristol, UK.
J Antimicrob Chemother. 1999 Nov;44(5):675-8. doi: 10.1093/jac/44.5.675.
Isolates of Staphylococcus aureus resistant to vancomycin have been reported but appear to be extremely rare. However, isolates displaying hetero-resistance to vancomycin (hVRSA) are reportedly common in parts of Japan (9.3% of MRSA isolated from a group of university hospitals). We have investigated the reliability of the proposed method for detection of hetero-resistant isolates and the ability of clinical S. aureus isolates to express vancomycin resistance. The original method for identification of hVRSA was found to have poor reproducibility and may select for, rather than detect, vancomycin resistance. There appears to be a spectrum of heterogeneity in the expression of resistance to vancomycin among S. aureus. Until there is a clearer understanding of the mechanism and control of vancomycin resistance in S. aureus, and reliable tests are devised, the clinical relevance of different degrees of hetero-resistance cannot be assessed.
已报道了对万古霉素耐药的金黄色葡萄球菌分离株，但似乎极为罕见。然而，据报道，对万古霉素表现出异质性耐药（hVRSA）的分离株在日本部分地区很常见（从一组大学医院分离出的MRSA中占9.3%）。我们研究了所提出的检测异质性耐药分离株方法的可靠性以及临床金黄色葡萄球菌分离株表达万古霉素耐药性的能力。发现最初鉴定hVRSA的方法重现性差，可能会选择出万古霉素耐药性，而不是检测到它。金黄色葡萄球菌对万古霉素的耐药表达似乎存在一系列异质性。在对金黄色葡萄球菌中万古霉素耐药的机制和控制有更清晰的了解并设计出可靠的检测方法之前，无法评估不同程度异质性耐药的临床相关性。
