Community-Acquired Uropathogenic Escherichia coli, Antimicrobial Susceptibility, and Extended-Spectrum Beta-Lactamase Detection
April 2022, Vol 24, No 2

INTRODUCTION Urinary tract infection is the second-leading reason for consults in primary health care. Bacterial urinary tract infections are the most common, of which Escherichia coli is the main etiologic agent. Antimicrobial resistance and multidrug resistance complicate effective community treatment, especially if resistance is caused by extended-spectrum beta-lactamase production. WHO recommends that antimicrobial susceptibility be evaluated in different regions of the world at different times. Community-acquired E. coli’s susceptibility to colistin has not yet been studied in Cuba, and mcr-1 gene screening is necessary.

OBJECTIVE Evaluate community-acquired uropathogenic E. coli isolates’ susceptibility to antibiotics, including colistin, and identify extended-spectrum beta-lactamase–producing bacteria.

METHODS We conducted a descriptive cross-sectional study that included 281 community-acquired uropathogenic E. coli isolates (153 from the Isle of Youth Special Municipality’s Hygiene, Epidemiology, and Microbiology Center and 128 from Microbiology Laboratories of 7 institutions in Havana) from June 2016 through July 2018. We used the disk diffusion method to determine susceptibility to ampicillin, ampicillin/sulbactam, cefazolin, trimethoprim/sulfamethoxazole, ciprofloxacin, nitrofurantoin and fosfomycin. The disk elution method was used to determine susceptibility to colistin. The combined disk method was used to identify extended-spectrum beta-lactamases. Estimates were made regarding the frequency and percentages of antimicrobial susceptibility and resistance, as well as multidrug-resistance patterns.

RESULTS Of the 281 isolates, 68.3% (192/281) were resistant to ampicillin, 54.8% (154/281) were resistant to ciprofloxacin, and 49.5% (139/281) were resistant to trimethoprim/sulfamethoxazole. Resistance to colistin was not detected. On the other hand, 14.2% (40/281) were susceptible to the 8 antibiotics we evaluated, 22.1% (62/281) showed resistance to only 1 antibiotic, and 63.7% (179/281) were resistant to 2 or more antibiotics. In the extended-spectrum beta-lactamase determination, 34.5% (97/281) had inhibition zones ≤14 mm with cefazolin. Of those with inhibition zones, 64.9% (63/97) were positive in the phenotype test, and 35.1% (34/97) were negative. In extended-spectrum beta-lactamase–producing bacteria, 1.6% (1/63) were resistant to fosfomycin, and 3.2% (2/63) were resistant to nitrofurantoin. The most common multidrug-resistance pattern (22.9%; 30/131) was to ampicillin/sulbactam, ampicillin, cefazolin, ciprofloxacin, and trimethoprim/sulfamethoxazole.

CONCLUSIONS Uropathogenic E. coli resistance to the antibiotics most frequently used in community medical practice is quite common, and extended-spectrum beta-lactamase–producing bacteria is the mechanism for beta-lactam antibiotic resistance. Multidrug-resistance patterns include resistance to the antibiotics most used in community-acquired infections. Fosfomycin and nitrofurantoin are the most active in extended-spectrum beta-lactamase producing bacteria. All the isolates were susceptible to colistin.

KEYWORDS Uropathogenic Escherichia coli, urinary tract infections, microbial susceptibility tests, Cuba

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Carbapenamase-Producing Acinetobacter baumannii in China, Latin America and the Caribbean:
January 2022, Vol 24, No 1

INTRODUCTION Carbapenem-resistant Acinetobacter baumannii is a complex health problem, causing difficulties in clinical–therapeutic management worldwide. It is of particular concern in Latin America, the Caribbean and China, where it is an emerging health problem. Carbapenemases produced by these organisms inactivate carbapenem antibiotics. Monitoring circulating genotypes’ geographic dispersion contributes to more effective control measures. However, exhaustive studies on carbapenem-resistant A. baumannii are scarce.

OBJECTIVES Study the production of carbapenemases in clinical isolates of A. baumannii resistant to carbapenem antibiotics and the geographic distribution of the sequences circulating in China, Latin America and the Caribbean.

DATA ACQUISITION We followed PRISMA indications. We carried out a systematic search in Pubmed, BVS and CKNI on papers on A. baumannii and carbapenemases published during 2015–2020 in English, Spanish and Chinese, and selected 29 cross-sectional studies that met the search criteria. Studies were evaluated using JBI Critical Appraisal tools, and quantitative data were collated for meta-analysis using the Metaprop library in Stata15.

DEVELOPMENT OXA-type carbapenemases were detected in all studies; among A. baumannii resistant to carbapenem antibiotics, predominant types were OXA-23, OXA-24, OXA-54 and OXA-72; metallobetalactamases were identified less frequently than OXA carbapenemases. Only one clinical isolate producer of Class A carbapenemases (KPC) was identified in Colombia. In total, 41 sequence types were identified; in Latin America and the Caribbean the most common types were: ST79, ST25, ST1 and ST15; in China, the sequences ST195, ST208, ST191, ST368 and ST369 were the most prevalent. ST2 was found in both regions.

CONCLUSIONS The most prevalent carbapenemases and sequence types vary by region, indicating different ancestral strains. Microbiological surveillance, antibiotic use optimization, adequate infection treatment and timely control strategies are essential for carbapenem-resistant A. baumannii prevention and control in geographies such as Latin America, the Caribbean and China where such resistance is an emerging health problem.

KEYWORDS Acinetobacter baumannii, carbapenemase, genotype, epidemiology, Latin America, Caribbean region, China

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