Sensibilité aux antibiotiques des Escherichia coli isolés d’infections urinaires communautaires

High Prevalence of Multidrug-Resistant Escherichia coli in Urine Samples from Inpatients and Outpatients at a Tertiary Care Hospital in Sétif, Algeria

The worldwide dissemination of multidrug-resistant (MDR) Enterobacteriaceae is a major public health issue. The aim of this study was to investigate the prevalence of MDR Escherichia coli (MDR-EC) isolates, in inpatients/outpatients with urinary tract infections at Sétif University Hospital (Algeria). Bacterial cultures were obtained from 426 of the 3,944 urine samples collected from January 2015 to February 2017. Among these cultures, 215 E. coli isolates were identified by mass spectrometry, and 38 (17.7%) were MDR-EC (disk diffusion method): 36 produced only extended-spectrum β-lactamases (ESBL), one ESBL and a carbapenemase, and one only a cephalosporinase (double-disk synergy test). Multiplex PCR and sequencing analyses showed that 37 ESBL-producing isolates harbored genes encoding CTX-M enzymes (CTX-M-15 in 33 isolates, 89.19%; and CTX-M-14 group in four isolates, 10.81%). One CTX-M-15-producing isolate co-expressed also an OXA-48-like carbapenemase. Phylogenetic group analysis of the 37 ESBL-producing and 178 non-ESBL-producing isolates indicated that the most common phylogenetic group was B2 (54.05% of ESBL-producing and 48.31% of non-ESBL-producing isolates), followed by A and D for ESBL-, and by B1, A, and F for non-ESBL-producing isolates. This is the first report highlighting the presence of MDR-EC isolates that produce both CTX-M and OXA-48-like enzymes in Sétif, Algeria.

Epidemiology of urinary tract infections, bacterial species and resistances in primary care in France

General practitioners often have to manage urinary tract infections (UTI) with probabilistic treatments, although bacterial resistances are increasing. Therefore, the French Society of Infectious Diseases published new guidelines in 2014. The aim of this study was to investigate the bacterial epidemiology of UTI in the general population in primary care and analyse risk factors for Escherichia coli resistance to antibiotics. A cross-sectional study was conducted in 12 ambulatory laboratories. Patients over 18 years of age coming for urinalysis were included. Risk factors for UTI were collected using a questionnaire and the laboratory records. Bacteria meeting criteria for UTI were analysed. A positive urinalysis was found in 1119 patients, corresponding to 1125 bacterial isolates. The bacterial species were: E. coli (73 %), Enterococcus spp. (7 %), Klebsiella spp. (6 %), Proteus spp. (4 %), Staphylococcus spp. (3 %) and Pseudomonas spp. (2 %). Regardless of the bacteria, the most common resistance was that to co-trimoxazole: 27 % (95 % confidence interval [CI] = [0.24; 0.30]), followed by ofloxacin resistance: 16 % [0.14; 0.18]. Escherichia coli resistances to co-trimoxazole, ofloxacin, cefixime, nitrofurantoin and fosfomycin were, respectively, 25.5 % [0.23; 0.28], 17 % [0.14; 0.20], 5.6 % [0.04; 0.07], 2.2 % [0.01; 0.03] and 1.2 % [0.005; 0.02]. Independent risk factors for E. coli resistance to ofloxacin were age over 85 years (odds ratio [OR] = 3.08; [1.61; 5.87]) and a history of UTI in the last 6 months (OR = 2.34; [1.54; 3.52]). Our findings support the guidelines recommending fluoroquinolone sparing. The scarcity of E. coli resistance to fosfomycin justifies its use as a first-line treatment in acute cystitis. These results should be reassessed in a few years to identify changes in the bacterial epidemiology of UTI.

Evaluation of antimicrobial susceptibility of Escherichia coli strains isolated in Rabat University Hospital (Morocco)

BACKGROUND

Escherichia coli (E. coli) is the most commonly isolated bacteria in human pathology. In Morocco the data concerning the nature and the rates of antibiotic resistance of E. coli in both hospitals and city environment remains relatively poor and needs further investigations.

METHODS

During a 16 months period, E. coli isolates were collected from different culture specimens received in the Bacteriology Department of the Military teaching Hospital Mohammed-V-Rabat for routine diagnostic purposes. E. coli isolates were identified and their antimicrobial susceptibility pattern was determined.

RESULTS

A total of 1369 E. coli isolates comprising 33% (1369/4110) of culture-positive samples were consecutively collected. Isolates of E. coli were, in 40.5% (554/1369) of cases from hospitalized patients and in 59.5% (815/1369) of cases from outpatients. Urine isolates represented 82% (1123/1369) of the cases. High rates of resistance were found for amoxicillin (42.5%), cefalotin (30.4%), norfoloxacin (29.9%) and sulfamethoxazole (37.7%). The detection rate of ESBL was 6.1% (85/1369). In hospitalized patients 11.9% of the isolates of E. coli (66/554) had an ESBL phenotype while in outpatients cases only 2.3% of isolates of E. coli (19/815) had this phenotype.

CONCLUSIONS

Our findings suggest that more judicious use of antibiotics is needed especially in probabilistic treatment. The emergence of ESBL in the Moroccan cities is an indicator of the severity of this problem that is not limited to health care facilities.

Antibiotic Resistance, Virulence, and Genetic Background of Community-Acquired Uropathogenic Escherichia coli from Algeria

The aim of the study was to investigate antibiotic resistance mechanisms, virulence traits, and genetic background of 150 nonrepetitive community-acquired uropathogenic Escherichia coli (CA-UPEC) from Algeria. A rate of 46.7% of isolates was multidrug resistant. bla genes detected were blaTEM (96.8% of amoxicillin-resistant isolates), blaCTX-M-15 (4%), overexpressed blaAmpC (4%), blaSHV-2a, blaTEM-4, blaTEM-31, and blaTEM-35 (0.7%). All tetracycline-resistant isolates (51.3%) had tetA and/or tetB genes. Sulfonamides and trimethoprim resistance genes were sul2 (60.8%), sul1 (45.9%), sul3 (6.7%), dfrA14 (25.4%), dfrA1 (18.2%), dfrA12 (16.3%), and dfrA25 (5.4%). High-level fluoroquinolone resistance (22.7%) was mediated by mutations in gyrA (S83L-D87N) and parC (S80I-E84G/V or S80I) genes. qnrB5, qnrS1, and aac(6')-Ib-cr were rare (5.3%). Class 1 and/or class 2 integrons were detected (40.7%). Isolates belonged to phylogroups B2+D (50%), A+B1 (36%), and F+C+Clade I (13%). Most of D (72.2%) and 38.6% of B2 isolates were multidrug resistant; they belong to 14 different sequence types, including international successful ST131, ST73, and ST69, reported for the first time in the community in Algeria and new ST4494 and ST4529 described in this study. Besides multidrug resistance, B2 and D isolates possessed virulence factors of colonization, invasion, and long-term persistence. The study highlighted multidrug-resistant CA-UPEC with high virulence traits and an epidemic genetic background.

Antibiotic treatment of acute uncomplicated cystitis based on rapid urine test and local epidemiology: lessons from a primary care series

Background

Acute uncomplicated cystitis (AUC) is an ideal target of optimization for antibiotic therapy in primary care. Because surveillance networks on urinary tract infections (UTI) mix complicated and uncomplicated UTI, reliable epidemiological data on AUC lack. Whether the antibiotic choice should be guided by a rapid urine test (RUT) for leukocytes and nitrites has not been extensively studied in daily practice. The aim of this primary care study was to investigate local epidemiology and RUT-daily use to determine the optimal strategy.

Methods

General practitioners included 18–65 years women with symptoms of AUC, performed a RUT and sent urines for analysis at a central laboratory. Different treatment strategies were simulated based on RUT and resistance results.

Results

Among 347 enrolled patients, 78% had a positive urine culture. Escherichia coli predominated (71%) with high rates of susceptibility to nitrofurantoin (100%), fosfomycin (99%), ofloxacin (97%), and even pivmecillinam (87%) and trimethoprim-sulfamethoxazole (87%). Modelization showed that the systematic use of RUT would reduce by 10% the number of patients treated. Fosfomycin for patients with positive RUT offered a 90% overall bacterial coverage, compared to 98% for nitrofurantoin. 95% for ofloxacin, 86% for trimethoprim-sulfamethoxazole and 78% for pivmecillinam.

Conclusion

Local epidemiology surveillance data not biased by complicated UTI demonstrates that the worldwide increase in antibiotic resistance has not affected AUC yet. Fosfomycin first line in all patients with positive RUT seems the best treatment strategy for AUC, combining good bacterial coverage with expected low toxicity and limited effect on fecal flora.

Trial registration

The current study was registered at clinicaltrials.gov (NCT00958295)

[Bacteriological analysis of more than 600 febrile urinary infections managed in a community health network]

Community-acquired febrile urinary tract infections (UTI) in adult has received little attention in the literature. The objective of our study was to determinate the distribution of bacterial strains isolated from adults with community-acquired febrile UTI and antibiotic susceptibility patterns of Escherichia coli.

PATIENTS AND METHOD

We studied the SPHERES's databank. SPHERES is a Parisian medical community network aimed at securing and facilitating the ambulatory management of potentially serious acute illnesses. Each patient is included in the network according to specific clinical criteria and standardized medical data are recorded. We retrospectively studied the medical records of all patients treated for a pyelonephritis or a prostatitis between April 2005 and October 2008.

RESULTS

Five hundred and sixty-eight patients were enrolled: 410 women and 158 men. The overall bacteria's distribution was similar to that observed in previous strictly microbiological studies with a more prominent role of E. coli (87.5%) to the detriment of other species. The overall susceptibility of E. coli to antibiotics recommended in the empiric treatment of pyelonephritis and prostatitis was preserved: ciprofloxacin (95.8%), cefotaxime (98%), gentamicin (99.4%). In women over 65 years, the susceptibility of E. coli to systemic fluoroquinolones fell up 89.7%. This could affect the empiric oral treatment of pyelonephritis in older women.

CONCLUSIONS

We report the bacterial distribution and the resistance pattern of bacteria implicated in febrile urinary infections diagnosed and treated in a health network. It seems that E. coli resistance increased more in women more than 65 years than in men.

Managing urinary tract infections

Urinary tract infections (UTI) are common in childhood. Presence of pyuria and bacteriuria in an appropriately collected urine sample are diagnostic of UTI. The risk of UTI is increased with an underlying urological abnormality such as vesicoureteral reflux, constipation, and voiding dysfunction. Patients with acute pyelonephritis are at risk of renal scarring and subsequent complications such as hypertension, proteinuria with and without FSGS, pregnancy-related complications and even end-stage renal failure. The relevance and the sequence of the renal imaging following initial UTI, and the role of antimicrobial prophylaxis and surgical intervention are currently undergoing an intense debate. Prompt treatment of UTI and appropriate follow-up of those at increased risk of recurrence and/or renal scarring are important.