Analysis of results of PCR and culture.

<p>Analysis of results of PCR and culture.</p

PCR positive urine specimens with inconclusive culture results (n = 18).

<p>PCR positive urine specimens with inconclusive culture results (n = 18).</p

Amplification of serial dilutions of bacterial cells.

<p>Standard curves (top) of PCRs for detection of <i>Citrobacter/Enterobacter spp</i>. (yellow), <i>Klebsiella spp</i>. (blue), <i>E</i>.<i>coli</i> (red), <i>E</i>.<i>faecalis</i> (brown), <i>P</i>.<i>mirabilis</i> (dark blue), and <i>P</i>.<i>aeruginosa</i> (purple). The Cq values per dilution are shown below the figure. Cq values that correspond with 10³ and 10⁵ cfu/ml were underlined in blue and red, respectively.</p

PCR positive and culture positive urine specimens (n = 44).

<p>PCR positive and culture positive urine specimens (n = 44).</p

Graphic showing the correlation between positive cultures and PCR Cq values.

<p>Comparison of PCR and culture results for <i>E</i>. <i>coli</i>. Cq values of PCR are depicted in the blue bars ranging from Cq22-Cq40 on the left axis. The red bars depict positive cultures with growth of 10³, 10⁵, and >10⁵ cfu/ml on the right axis. Low Cq values correspond with high loads of micro-organisms, and thus with larger yield of positivity and quantities of cultures.</p

Analysis of results of PCR and the Seegene kit.

<p>Analysis of results of PCR and the Seegene kit.</p

The Widespread Presence of a Multidrug-Resistant <i>Escherichia coli</i> ST131 Clade among Community-Associated and Hospitalized Patients

<div><p>Background & Aims</p><p>The extent of entry of multidrug-resistant <i>Escherichia coli</i> from the community into the hospital and subsequent clonal spread amongst patients is unclear. To investigate the extent and direction of clonal spread of these bacteria within a large teaching hospital, we prospectively genotyped multidrug-resistant <i>E</i>. <i>coli</i> obtained from community- and hospital associated patient groups and compared the distribution of diverse genetic markers.</p><p>Methods</p><p>A total of 222 <i>E</i>. <i>coli</i>, classified as multi-drug resistant according to national guidelines, were retrieved from both screening (n = 184) and non-screening clinical cultures (n = 38) from outpatients and patients hospitalized for various periods. All isolates were routinely genotyped using an amplified fragment length polymorphism (AFLP) assay and real-time PCR for CTX-M genes. Multi-locus sequence typing was additionally performed to confirm clusters. Based on demographics, patients were categorized into two groups: patients that were not hospitalized or less than 72 hours at time of strain isolation (group I) and patients that were hospitalized for at least 72 hours (group II).</p><p>Results</p><p>Genotyping showed that most multi-drug resistant <i>E</i>. <i>coli</i> either had unique AFLP profiles or grouped in small clusters of maximally 8 isolates. We identified one large ST131 clade comprising 31% of all isolates, containing several AFLP clusters with similar profiles. Although different AFLP clusters were found in the two patient groups, overall genetic heterogeneity was similar (35% vs 28% of isolates containing unique AFLP profiles, respectively). In addition, similar distributions of CTX-M groups, including CTX-M 15 (40% and 44% of isolates in group I and II, respectively) and ST131 (32% and 30% of isolates, respectively) were found.</p><p>Conclusion</p><p>We conclude that multi-drug resistant <i>E</i>. <i>coli</i> from the CTX-M 15 associated lineage ST131 are widespread amongst both community- and hospital associated patient groups, with similar genetic diversity and similar distributions of genetic markers.</p></div

Antimicrobial resistance rates of MDR <i>E</i>. <i>coli</i>.

<p>Antimicrobial resistance rates of MDR <i>E</i>. <i>coli</i>.</p

Basic parameters of included patients.

<p>Basic parameters of included patients.</p

Genotyping of multi-drug resistant <i>E</i>. <i>coli</i>.

<p>Cluster analysis based on AFLP data with (<b>A)</b> similarity matrix of community associated isolates (group I) and (<b>B)</b> hospital associated isolates (group II). AFLP clusters are indicated by dark boxes, whites are unique profiles. The green bar adjacent to the similarity matrix indicates Sequence Type 131, color-coded boxes to the left of this indicate clusters with identical AFLP profiles.</p