Resistance and virulence potential of uropathogenic Escherichia coli strains isolated from patients hospitalized in urology departments: a French prospective multicentre study.

We characterized antibiotic resistance and virulence of uropathogenic Escherichia coli (UPEC) strains isolated from urinary tract infections (UTIs) in patients hospitalized in urology departments. A prospective multicentre study was initiated from March 2009 and lasted until February 2010 in French urology units. All patients with asymptomatic bacteriuria (ABU), acute cystitis, acute pyelonephritis or acute prostatitis in whom UPEC was detected were included. Antimicrobial resistance and virulence factors were compared among the different groups. To identify independent associations between virulence markers and the risk of UTI, we used a multivariate logistic regression. We included 210 patients (mean age: 65.8 years; 106 female). Episode of UTI was community acquired in 72.4 %. ABU was diagnosed in 67 cases (31.9 %), cystitis in 52 cases (24.7 %), pyelonephritis in 35 cases (16.7 %) and prostatitis in 56 cases (26.7 %). ABU was more frequent in patients with a urinary catheter (76.1 vs 23.9 %, P<0.001). The resistance rate was 7.6 and 24.8 % for cefotaxime and ciprofloxacin, respectively. UPEC isolated from infections belonged more frequently to phylotypes B2 and D (P =0.07). The papG allele II and papA, papC, papE, kpsMTII and iutA genes were significantly more frequent in infecting strains (P<0.05). In multivariate analysis, strains susceptible to ciprofloxacin were significantly associated with papG allele II (P=0.007), kpsMTK1 (P<0.001) and hlyA (P<0.001) compared with the ciprofloxacin-resistant strains. To the best of our knowledge, this is the first study evaluating the antibiotic resistance and virulence features of UPEC isolated from patients hospitalized in urology departments. High resistance rates were observed, notably for ciprofloxacin, highlighting the importance of a reinforced surveillance in this setting.

Diagnostic criteria of urinary tract infection in male patients with spinal cord injury.

BACKGROUND: The current diagnostic criteria of urinary tract infection (UTI) in male patients with spinal cord injury (SCI) are not clear. METHODS: The authors studied 381 episodes of "symptomatic" UTI (209 participants) and 277 episodes of "asymptomatic" UTI (205 participants) in male SCI patients using intermittent catheterization. UTI was defined as a bacterial count ≥10(2) colony-forming units (cfu)/mL (American Paraplegia Society criterion). Univariate analysis and receiver operating characteristic (ROC) curve analysis were used to determine optimal cfu and white blood cell (WBC) thresholds. RESULTS: The most prevalent clinical signs, alone or in combination, were cloudy and/or malodorous urine (51.4%), onset of urinary incontinence (51.2%), fatigue (41.7%), fever (30.7%), and increased spasticity (30.2%). Urine cfu and WBC levels in patients with only one sign, including fever, were not significantly higher than those in asymptomatic controls. WBC, but not cfu, levels increased significantly with the number of signs (P = .026). Univariate analysis and ROC curve analysis failed to identify cfu, WBC, or a combination of cfu and WBC count thresholds, allowing discrimination between the symptomatic and asymptomatic UTI groups. CONCLUSIONS: Clinical signs of UTI correlate poorly with the urine cfu and WBC levels in SCI patients, except for a positive relationship between WBC counts and the number of signs. Fever alone has no higher diagnostic value. There are no satisfactory cfu and WBC thresholds: thresholds more restrictive than the current American Paraplegia Society criteria provide higher specificity values but with equivalent loss of sensitivity.

Extended-spectrum cephalosporinase in Acinetobacter baumannii.

An AmpC-type beta-lactamase conferring high-level resistance to expanded-spectrum cephalosporins and monobactams was characterized from an Acinetobacter baumannii clinical isolate. This class C beta-lactamase (named ADC-33) possessed a Pro210Arg substitution together with a duplication of an Ala residue at position 215 (inside the Omega-loop) compared to a reference AmpC cephalosporinase from A. baumannii. ADC-33 hydrolyzed ceftazidime, cefepime, and aztreonam at high levels, which allows the classification of this enzyme as an extended-spectrum AmpC (ESAC). Site-directed mutagenesis confirmed the role of both substitutions in its ESAC property.

Detection of Campylobacter jejuni by culture and real-time PCR in a French cohort of patients with Guillain-Barre syndrome.

Bacteriological culture and real-time PCR (RT-PCR) were used to detect Campylobacter jejuni in fecal samples from a French cohort of 237 patients with Guillain-Barré syndrome (GBS). We provide evidence that diverse serotypes and genotypes of C. jejuni are a major trigger of GBS in France.

Intermediate mutation frequencies favor evolution of multidrug resistance in Escherichia coli.

In studying the interplay between mutation frequencies and antibiotic resistance among Escherichia coli natural isolates, we observed that modest modifications of mutation frequency may significantly influence the evolution of antibiotic resistance. The strains having intermediate mutation frequencies have significantly more antibiotic resistances than strains having low and high mutation frequencies.

Spread of a Klebsiella pneumoniae strain producing a plasmid-mediated ACC-1 AmpC beta-lactamase in a teaching hospital admitting disabled patients.

We describe a large outbreak involving a Klebsiella pneumoniae strain producing a plasmid-encoded ACC-1 type AmpC beta-lactamase in a hospital caring for patients with motor impairment. The epidemic strain was isolated from 57 patients in six wards between September 1999 and May 2003 and caused clinical infections in 19 patients.

Molecular typing of Legionella pneumophila serogroup 1 isolates from patients and the nosocomial environment by arbitrarily primed PCR and pulsed-field gel electrophoresis.

The ubiquity of Legionella pneumophila in aquatic habitats means that epidemiological evaluation is important for the investigation and control of nosocomial outbreaks of legionellosis. Pulsed-field gel electrophoresis (PFGE) of chromosomal DNA following digestion with SfiI is considered to be one of the most discriminative methods for detecting DNA polymorphisms amongst L. pneumophila serogroup 1 (Lp1) isolates. This paper describes an arbitrarily primed PCR (AP-PCR) method with three different primers (20-mers) for detecting DNA polymorphisms of Lp1 isolates. The AP-PCR assay was compared with PFGE analysis. Both experimental methods were found to have good discriminatory power (discrimination index of 98% and 94.3%, respectively) with 27 unrelated isolates from different geographical areas collected between 1987 and 1997. Furthermore, when the AP-PCR was used in the epidemiological investigation of nosocomial cases of infection, convergent results with the three primers allowed an epidemiological link to be established between isolates from patients and their environment. The AP-PCR method, which is rapid and easy to perform, gave results at least as discriminatory as those obtained with the PFGE method and is proposed for use in the molecular typing of Lp1 outbreaks.