Utility of bile esculin azide agar for screening of stool samples for vancomycin resistant enterococci from patients with gut colonization

Background: Due to increased prevalence of vancomycin resistant enterococci (VRE) in hospital settings as an important nosocomial pathogen, microbiology laboratories should be prepared with test protocol for prompt detection and reporting of these resistant organisms. This helps in appropriate treatment of patients without delay and implementation of infection control measures in order to prevent spread of such infections. With this background present study was conducted to demonstrate utility of bile esculin azide agar with vancomycin (BEAV) for screening of enterococci for vancomycin drug resistance.Methods: Over a period of one year 200 stool samples were collected from hospitalized patients in a tertiary care hospital. Samples were inoculated on bile esculin azide agar with vancomycin (6ug/ml) to screen for vancomycin drug resistance in enterococci isolated from stool samples. Vancomycin drug resistance was confirmed by agar dilution method.Results: Out of 200 stool samples collected from hospitalized patients, 13 (6.5%) samples showed growth on bile esculin azide agar with vancomycin (6 µg/ml). Of these 13 isolates, 12 (92.3%) isolates were confirmed as VRE by agar dilution method and demonstrated minimum inhibitory concentration (MIC) of ≥32 µg/ml and all 12 isolates were identified as E. faecium. One (7.7%) isolate grown on BEAV was identified as E. gallinarum and showed MIC value of 8 µg/ml.Conclusions: Present study recommends use of bile esculin azide agar with vancomycin (6 µg/ml) as a screening medium for isolation of VRE from stool samples which usually carries mixed commensal flora of gastrointestinal tract

Evaluating the association of multiple single nucleotide polymorphisms with response to gemcitabine and platinum combination chemotherapy in urothelial carcinoma of the bladder .

OBJECTIVE: To examine germline single nucleotide polymorphisms (SNPs) as markers of response to gemcitabine platinum (GP) combination chemotherapy in urothelial carcinoma (UC). METHODS: Saliva or blood was prospectively collected from 216 patients treated with GP for UC of the bladder between 1991 and 2011. Based on reported associations with gemcitabine and cisplatin response or putative mechanisms of gemcitabine or cisplatin/carboplatin activity, we selected SNPs of interest and were able to genotype 59 SNPs (using the SequenomMass ARRAYiPLEX platform) in 261 patients randomly split 2/3 into a training set (n = 174) and 1/3 into a test set (n = 87). Logistic regression was used to test the association between response to GP and SNPs. RESULTS: The median age at diagnosis was 64 years (range: 28 - 85) for the discovery set and 67 years (range: 30 - 84) for the validation set. Males composed 76% and 69%, and white non-Hispanics composed 88% and 91% of the training and test validation sets, respectively. Three SNPs on GALNTL4 (rs7937567, rs12278731, and rs9988868) and one intergenic SNP (rs1321391) were significantly associated with response to GP in the training set and were used to build a SNP score. However, when assessed in the test set, the SNP score was not significantly associated with response. CONCLUSION: Multiple SNPs selected from previous studies failed to predict response to GP in this cohort. Larger studies capable of accounting for population-based allele frequency heterogeneity may be required for replication of genetic alterations important to pharmacogenomics