Impact of Prior Antibiotic Use in Primary Care on Escherichia coli Resistance to Third Generation Cephalosporins: A Case-Control Study

Antibiotic deprescribing: Spanish general practitioners' views on a new strategy to reduce inappropriate use of antibiotics in primary care

BACKGROUND

A doctor may recommend that a patient stop an antibiotic course before its scheduled completion time if further treatment may cause more harm than benefit.

OBJECTIVES

This study explores general practitioners' (GP) opinions about the use of antibiotic deprescribing (AD) in general practice.

METHODS

A cross-sectional, questionnaire-based study answered from February to March 2022. GPs (n = 6,083) affiliated with the largest Spanish scientific society of primary care were invited to participate. The survey included two statements related to use and fourteen views about AD rated by GPs using a 5-item Likert scale.

RESULTS

Eleven hundred and seven doctors completed the surveys (18.2%), of whom 92.5% (95% confidence interval [CI] 90.8-94%) reported having used the AD strategy in their practice at least once. GPs felt very confident in using a deprescribing strategy in patients with common cold and influenza (97.6% and 93.5%, respectively) but less with acute bronchitis (45.5%); 12.1% (95% CI, 10.2-14.2%) considered this practice harmful to patients. Respondents reported using AD more frequently when they initiated the antibiotic course (96.8%; 95% CI, 95.5-97.7) than when the treatment was initiated by another doctor (52.3%; 95% CI, 49.3-55.3%). However, doctors aged >60 years were more prone to use AD compared with younger colleagues (64.5% vs. 50%; p < 0.005).

CONCLUSION

The GPs in this study employ the strategy of AD. Nonetheless, essential differences lie in their views of the way the strategy is used. Further studies are warranted to explore the beliefs behind these perceptions and promote wider use of AD by GPs.

Prevalence of Extended-Spectrum β-Lactamase-Resistant Genes in Escherichia coli Isolates from Central China during 2016-2019

The emergence and dissemination of Escherichia coli (E. coli) strains that produce extended-spectrum beta-lactamases (ESBLs) represents a major public health threat. The present study was designed to evaluate the prevalence and characteristics of ESBL-producing Escherichia coli isolates from chickens in central China during 2016-2019. A total of 407 E. coli strains isolated from 581 chicken swabs were identified conventionally and analyzed for various cephalosporin susceptibility by disk-diffusion assay. ESBL-producing strains were screened using the double=disk synergy test and ESBL-encoding genes were carried out by PCR/sequencing. A total of 402 E. coli isolates exhibited strong resistance to first- to fourth-generation cephalosporins and monobactam antibiotics, especially cefazolin (60.69%), cefuroxime (54.05%), cefepime (35.14%), ceftriaxone (54.30%), and aztreonam (40.29%). Piperacillin/tazobactam (1.72%) was the most effective drug against the strains, but the resistance rates increased each year. Among the isolates, 262 were identified as ESBL producers and the isolation rates for the ESBL producers increased from 63.37% to 67.35% over the four years. CTX-M (97.33%) was the most prevalent type, followed by TEM (76.72%) and SHV (3.05%). The most common ESBL genotype combination was bla_TEM + bla_CTX-M (74.46%), in which the frequency of carriers increased steadily, followed by bla_CTX-M + bla_SHV (3.05%). In addition, the most predominant specific CTX-M subtypes were CTX-M-55 (48.47%) and CTX-M-1 (17.94%), followed by CTX-M-14 (11.01%), CTX-M-15 (8.02%), CTX-M-9 (6.11%), CTX-M-65 (4.58%), and CTX-M-3 (1.15%). Moreover, a novel multiplex qPCR assay was developed to detect bla_CTX-M, bla_TEM, and bla_SHV, with limits of detection of 2.06 × 10¹ copies/μL, 1.10 × 10¹ copies/μL, and 1.86 × 10¹ copies/μL, respectively, and no cross-reactivity with other ESBL genes and avian pathogens. The assays exhibited 100% sensitivity and specificities of 85%, 100%, and 100% for bla_CTX-M, bla_TEM, and bla_SHV, respectively. In conclusion, our findings indicated that ESBL-producing E.coli strains isolated from chickens in central China were highly resistant to cephalosporins and frequently harbored diversity in ESBL-encoding genes. These isolates can pose a significant public health risk. The novel multiplex qPCR method developed in this study may be a useful tool for molecular epidemiology and surveillance studies of ESBL genes.

Effect of Fluoroquinolone Use in Primary Care on the Development and Gradual Decay of Escherichia coli Resistance to Fluoroquinolones: A Matched Case-Control Study

The reversibility of bacterial resistance to antibiotics is poorly understood. Therefore, the aim of this study was to determine, over a period of five years, the effect of fluoroquinolone (FQ) use in primary care on the development and gradual decay of Escherichia coli resistance to FQ. In this matched case−control study, we linked three sources of secondary data of the Health Service of the Autonomous Province of Bolzano, Italy. Cases were all those with an FQ-resistant E. coli (QREC)-positive culture from any site during a 2016 hospital stay. Data were analyzed using conditional logistic regression. A total of 409 cases were matched to 993 controls (FQ-sensitive E. coli) by the date of the first isolate. Patients taking one or more courses of FQ were at higher risk of QREC colonization/infection. The risk was highest during the first year after FQ was taken (OR 2.67, 95%CI 1.92−3.70, p < 0.0001), decreased during the second year (OR 1.54, 95%CI 1.09−2.17, p = 0.015) and became undetectable afterwards (OR 1.09, 95%CI 0.80−1.48, p = 0.997). In the first year, the risk of resistance was highest after greater cumulative exposure to FQs. Moreover, older age, male sex, longer hospital stays, chronic obstructive pulmonary disease (COPD) and diabetes mellitus were independent risk factors for QREC colonization/infection. A single FQ course significantly increases the risk of QREC colonization/infection for no less than two years. This risk is higher in cases of multiple courses, longer hospital stays, COPD and diabetes; in males; and in older patients. These findings may inform public campaigns and courses directed to prescribers to promote rational antibiotic use.

Use and quality of point-of-care microscopy, urine culture and susceptibility testing for urinalysis in general practice

Objective: To describe the use and quality of point-of-care (POC) microscopy, urine culture and susceptibility testing performed in general practice in Northern Denmark from 2013 to 2018.Design: Descriptive studySetting: General practices receiving a fee for examining urine samples.Subjects: Simulated urine samples containing uropathogenic bacteria distributed by the organisation for improvement of microbiological quality (MIKAP).Main outcome measures: Percentage of use and correct answers for microscopy, culture and susceptibility testing.Results: A total of 5361 samples were analysed by the use of microscopy (39.7%), culture (66.0%) and/or susceptibility testing (76.5%). For culture, Flexicult SSI urinary kittm (87.6%) demonstrated the highest percentage of correct answers followed by chromogenic agar (85.1%) and 2-plate dipslide (85.2%). Mueller Hinton agar with tablets had the highest percentage of correct answers for susceptibility testing of most bacterial strains (84.6%), followed by Flexicult (77.2%). Furthermore, susceptibility testing with tablets (range: 76.1-84.6%) was found to be more accurate than discs (range: 72.9-75.5%). Overall, the highest percentage of correct answers was obtained when examining urine samples containing Escherichia coli: Microscopy (78.3%), culture (87.0%) and susceptibility testing (range: 84.3-90.7%).Conclusion: The quality of POC testing in general practice was high when examining urine samples containing the most common uropathogen E. coli. Surprisingly, susceptibility testing was more frequently used than culture. This approach may compromise the treatment decision as only cultures contribute with information about the flora composition and bacterial quantification. Interestingly, microscopy was the least used method even though the result may be reached within a few minutes.Key pointsThe quality of POC tests (microscopy, urine culture, susceptibility testing) performed in general practice was high when examining urine containing E. coli, whereas difficulties were observed for samples including S. saprophyticus or K. pneumoniae.Susceptibility testing was more often performed than urine culture, which indicates a problem as only urine cultures contribute with information about the flora composition and bacterial quantification.