| Title | Prevalence and characterization of heterogeneous vancomycin-intermediate Staphylococcus aureus (hVISA) from 14 cities in China. | | Author(s) | Sun W, Chen H, Liu Y, Zhao C, Nichols WW, Chen M, Zhang J, Ma Y, Wang H | | Institution | Department of Clinical Laboratory, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, 100730, People's Republic of China; Graduate School, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, 100730, People's Republic of China; AstraZeneca Pharmaceuticals LP, Waltham, MA 02451, USA; Chinese Center for Disease Control and Prevention, Beijing, 102206, People's Republic of China; National Institute for the Control of Pharmaceutical and Biological Products, Beijing, 100050, People's Republic of China. | | Source | Antimicrob Agents Chemother 2009 Jun 22. | | Abstract | The prevalence of hVISA among 1,012 vancomycin-susceptible MRSA isolates collected from 14 cities in China from 2005 to 2007 was 13-16 %, as determined by a combination of: (i) measuring by the 'modified population analysis profile - area under the curve' method (PAP-AUC); and (ii) estimating from the results of a screening method of measured sensitivity and specificity. Two hundred isolates from blood were chosen as a sub-set for measuring the sensitivity and specificity of several previously described screening methods, using PAP-AUC as reference. During this testing, one isolate was found to be VISA so was not used in evaluating the screening tests. Of the other 199, 13.1% (26/199) were hVISA as assessed by PAP-AUC. A screening cascade of brain heart infusion agar containing teicoplanin (5 mg/L) followed by subjecting the positive isolates to a macro-Etest method was applied to the 812 non-blood isolates, yielding 149 positives. From this, and adjusting for sensitivity (0.423) and specificity (0.861), the prevalence was estimated as 15.7 %. The precision of that estimate was assessed by re-applying the screening cascade to 120 randomly-selected isolates from the 812 and simultaneously determining hVISA status by PAP-AUC. Because PAP-AUC is impractical for large numbers of isolates, the screen-based estimation method is useful as a first approximation of the prevalence of hVISA. Of the 27 VISA/hVISA from blood: 22.2% and 74.1% were SCCmec II and III, while 77.8% and 22.2% were agr 1 and agr 2, respectively; MIC ranges were 0.5-4 mg/L for vancomycin and 0.25-1 mg/L for daptomycin. | | Language | ENG | | Pub Type(s) | JOURNAL ARTICLE
| | PubMed ID | 19546358 |
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