US outpatient antibiotic prescribing variation according to geography, patient population, and provider specialty in 2011

Increased Antimicrobial and Multidrug Resistance Downstream of Wastewater Treatment Plants in an Urban Watershed

Development and spread of antimicrobial resistance (AMR) and multidrug resistance (MDR) through propagation of antibiotic resistance genes (ARG) in various environments is a global emerging public health concern. The role of wastewater treatment plants (WWTPs) as hot spots for the dissemination of AMR and MDR has been widely pointed out by the scientific community. In this study, we collected surface water samples from sites upstream and downstream of two WWTP discharge points in an urban watershed in the Bryan-College Station (BCS), Texas area, over a period of nine months. E. coli isolates were tested for resistance to ampicillin, tetracycline, sulfamethoxazole, ciprofloxacin, cephalothin, cefoperazone, gentamycin, and imipenem using the Kirby-Bauer disc diffusion method. Antimicrobial resistant heterotrophic bacteria were cultured on R2A media amended with ampicillin, ciprofloxacin, tetracycline, and sulfamethoxazole for analyzing heterotrophic bacteria capable of growth on antibiotic-containing media. In addition, quantitative real-time polymerase chain reaction (qPCR) method was used to measure eight ARG – tetA, tetW, aacA, ampC, mecA, ermA, blaTEM, and intI1 in the surface water collected at each time point. Significant associations (p < 0.05) were observed between the locations of sampling sites relative to WWTP discharge points and the rate of E. coli isolate resistance to tetracycline, ampicillin, cefoperazone, ciprofloxacin, and sulfamethoxazole together with an increased rate of isolate MDR. The abundance of antibiotic-resistant heterotrophs was significantly greater (p < 0.05) downstream of WWTPs compared to upstream locations for all tested antibiotics. Consistent with the results from the culture-based methods, the concentrations of all ARG were substantially higher in the downstream sites compared to the upstream sites, particularly in the site immediately downstream of the WWTP effluent discharges (except mecA). In addition, the Class I integron (intI1) genes were detected in high amounts at all sites and all sampling points, and were about ∼20 times higher in the downstream sites (2.5 × 10⁷ copies/100 mL surface water) compared to the upstream sites (1.2 × 10⁶ copies/100 mL surface water). Results suggest that the treated WWTP effluent discharges into surface waters can potentially contribute to the occurrence and prevalence of AMR in urban watersheds. In addition to detecting increased ARG in the downstream sites by qPCR, findings from this study also report an increase in viable AMR (HPC) and MDR (E. coli) in these sites. This data will benefit establishment of improved environmental regulations and practices to help manage AMR/MDR and ARG discharges into the environment, and to develop mitigation strategies and effective treatment of wastewater.

Prescription Antibiotic Use Among the US population 1999-2018: National Health and Nutrition Examination Surveys

Background

Antibiotic resistance has been identified as a public health threat both in the United States and globally. The United States published the National Strategy for Combating Antibiotic Resistance in 2014, which included goals to reduce inappropriate outpatient antibiotic use.

Methods

This cross-sectional study was conducted using National Health and Nutrition Examination Surveys (NHANES) years 1999–2018. Weighted prevalence of past 30-day nontopical outpatient antibiotic use was calculated, as well as the change in prevalence from 1999–2002 to 2015–2018 and 2007–2010 to 2015–2018, both overall and for subgroups. Associations with past 30-day nontopical outpatient antibiotic use in 2015–2018 were examined using predictive margins calculated by multivariable logistic regression.

Results

The overall prevalence of past 30-day nontopical outpatient antibiotic use adjusted for age, sex, race/ethnicity, poverty status, time of year of the interview, and insurance status from 1999–2002 to 2015–2018 changed significantly from 4.9% (95% CI, 3.9% to 5.0%) to 3.0% (95% CI, 2.6% to 3.0%), with the largest decrease among children age 0–1 years. From 2007–2010 to 2015–2018, there was no significant change (adjusted prevalence ratio [adjPR], 1.0; 95% CI, 0.8 to 1.2). Age was significantly associated with antibiotic use, with children age 0–1 years having significantly higher antibiotic use than all other age categories >6 years. Being non-Hispanic Black was negatively associated with antibiotic use as compared with being non-Hispanic White (adjPR, 0.6; 95% CI, 0.4 to 0.8).

Conclusions

While there were declines in antibiotic use from 1999–2002 to 2015–2018, there were no observed declines during the last decade.

Appropriateness of Antibiotic Prescription for Prophylactic Purposes among Italian Dental Practitioners: Results from a Cross-Sectional Study

The primary objective of this study was to investigate the pattern of antibiotic prescription for prophylaxis purposes among Italian DPs (dental practitioners). A nationwide cross-sectional study was conducted using a multi-stage sampling design. A structured questionnaire was used to collect socio-demographic data and information about antibiotic prophylaxis (AP) prescriptions for selected dental diagnoses and surgical procedures. The presence of an indication and appropriateness of AP were defined according to international guidelines. In total, 563 DPs answered the questionnaire (response rate 52.6%). The proportions of DPs who prescribed AP in the presence of an indication ranged from 39.1% for luxation injury with soft tissue trauma to 73.1% for dental implants, whilst DPs who prescribed AP in healthy patients ranged from 41.9% in luxation injury with soft tissue trauma to 70.3% for bone grafting. The course of AP reported by DPs was not consistent with the guidelines in 70.9% of explored procedures. A high proportion of AP prescriptions before dental procedures were unnecessary. This highlights the urgent need to incorporate recommendations for best practices into national and local protocols as soon as they are established. Specific antibiotic stewardship strategies targeted to DPs should be implemented and assessed for effectiveness in improving prescribing of antibiotics.

Regulation of the Mitochondrion-Fatty Acid Axis for the Metabolic Reprogramming of Chlamydia trachomatis during Treatment with β-Lactam Antimicrobials

Infection with the obligate intracellular bacterium Chlamydia trachomatis is the most common bacterial sexually transmitted disease worldwide. Since no vaccine is available to date, antimicrobial therapy is the only alternative in C. trachomatis infection. However, changes in chlamydial replicative activity and the occurrence of chlamydial persistence caused by diverse stimuli have been proven to impair treatment effectiveness. Here, we report the mechanism for C. trachomatis regulating host signaling processes and mitochondrial function, which can be used for chlamydial metabolic reprogramming during treatment with β-lactam antimicrobials. Activation of signal transducer and activator of transcription 3 (STAT3) is a well-known host response in various bacterial and viral infections. In C. trachomatis infection, inactivation of STAT3 by host protein tyrosine phosphatases increased mitochondrial respiration in both the absence and presence of β-lactam antimicrobials. However, during treatment with β-lactam antimicrobials, C. trachomatis increased the production of citrate as well as the activity of host ATP-citrate lyase involved in fatty acid synthesis. Concomitantly, chlamydial metabolism switched from the tricarboxylic acid cycle to fatty acid synthesis. This metabolic switch was a unique response in treatment with β-lactam antimicrobials and was not observed in gamma interferon (IFN-γ)-induced persistent infection. Inhibition of fatty acid synthesis was able to attenuate β-lactam-induced chlamydial persistence. Our findings highlight the importance of the mitochondrion-fatty acid interplay for the metabolic reprogramming of C. trachomatis during treatment with β-lactam antimicrobials.IMPORTANCE The mitochondrion generates most of the ATP in eukaryotic cells, and its activity is used for controlling the intracellular growth of Chlamydia trachomatis Furthermore, mitochondrial activity is tightly connected to host fatty acid synthesis that is indispensable for chlamydial membrane biogenesis. Phospholipids, which are composed of fatty acids, are the central components of the bacterial membrane and play a crucial role in the protection against antimicrobials. Chlamydial persistence that is induced by various stimuli is clinically relevant. While one of the well-recognized inducers, β-lactam antimicrobials, has been used to characterize chlamydial persistence, little is known about the role of mitochondria in persistent infection. Here, we demonstrate how C. trachomatis undergoes metabolic reprogramming to switch from the tricarboxylic acid cycle to fatty acid synthesis with promoted host mitochondrial activity in response to treatment with β-lactam antimicrobials.

Concordance of antibiotic prescribing with the American Dental Association acute oral infection guidelines within Veterans' Affairs (VA) dentistry

OBJECTIVE

United States dentists prescribe 10% of all outpatient antibiotics. Assessing appropriateness of antibiotic prescribing has been challenging due to a lack of guidelines for oral infections. In 2019, the American Dental Association (ADA) published clinical practice guidelines (CPG) on the management of acute oral infections. Our objective was to describe baseline national antibiotic prescribing for acute oral infections prior to the release of the ADA CPG and to identify patient-level variables associated with an antibiotic prescription.

DESIGN

Cross-sectional analysis.

METHODS

We performed an analysis of national VA data from January 1, 2017, to December 31, 2017. We identified cases of acute oral infections using International Classification of Disease, Tenth Revision, Clinical Modification (ICD-10-CM) codes. Antibiotics prescribed by a dentist within ±7 days of a visit were included. Multivariable logistic regression identified patient-level variables associated with an antibiotic prescription.

RESULTS

Of the 470,039 VA dental visits with oral infections coded, 12% of patient visits with irreversible pulpitis, 17% with apical periodontitis, and 28% with acute apical abscess received antibiotics. Although the median days' supply was 7, prolonged use of antibiotics was frequent (≥8 days, 42%-49%). Patients with high-risk cardiac conditions, prosthetic joints, and endodontic, implant, and oral and maxillofacial surgery dental procedures were more likely to receive antibiotics.

CONCLUSIONS

Most treatments of irreversible pulpitis and apical periodontitis cases were concordant with new ADA guidelines. However, in cases where antibiotics were prescribed, prolonged antibiotic courses >7 days were frequent. These findings demonstrate opportunities for the new ADA guidelines to standardize and improve dental prescribing practices.

Medical Cost of Upper Respiratory Tract Infections in Children in Ambulatory Care

OBJECTIVE

The aim of this study was to estimate the direct cost per episode and the annual cost for upper respiratory tract infection (URTI) in children in Ambulatory Health Centers of the Ministry of Public Health (MSP) of Ecuador.

METHODS

A cost of illness study with a provider perspective was carried out through a micro-costing of health resources and valuated in international dollars. Medical visits, laboratory tests, imaging examinations, and other procedures were valued using the tariff framework of services for the National Health System, and for prescribed medication a reported cost registry of pharmacy purchases made in the year of study was used.

RESULTS

We included 380 electronic health records of children. We found a re-consultation rate of 22.89%, a medicine prescription rate of 95.52%, and an antibiotic prescription rate of 45.26%. The first medical consultation accounted for 71.9% of the total cost of URTI, the following visits accounted for 11.82%, and medication accounted for 14.68%. Antibiotics accounted for 58.92% of the total cost of medication.

CONCLUSION

The direct medical cost to the MSP of Ecuador of 1 episode of URTI in children in primary care was around I$37.28 (2017 dollars) (95% CI: I$35.81-I$38.75). The total cost of URTI cases in children to the MSP in 2017 was at least I$50.478 million (2017 dollars) (95% CI I$48.527m-I$52.523m). Re-consultation and the prescription of medication represent an important component of the direct cost of medical care of URTI.

Trends in the consumption of antibiotics in the Lebanese community between 2004 and 2016

Background Antibiotic resistance has reached an alarming rate globally especially in middle-income countries such as Lebanon. The development of antibiotic resistance is strongly linked to the increased population's injudicious consumption of antibiotics. Objective This study aims to explore the trends of antibiotics consumption in the Lebanese community, between 2004 and 2016, to inform rational use of antibiotics. Setting The study was performed using the Intercontinental Marketing Statistics (IMS) Health Lebanon database Method This is an observational longitudinal study conducted through a review of the IMS database. The annual antibiotics consumption was determined by the Defined Daily Dose (DDD)/1000 inhabitants/day (DID). The trends of antibiotics consumption were then categorized by antibiotic class and spectrum of activity. Main outcome measure The total consumption of antibiotics in Lebanon and the classes of antibiotics used by the community. Results Total community consumption of antibiotics, measured by DDD/1000 inhabitants/day (DID), significantly increased from 18.71 in 2004 to 31.26 in 2016. Penicillin combinations, quinolones, third-generation cephalosporins, tetracyclines, and carbapenems showed significant uptrends, in contrast to first-generation cephalosporins, sulfonamides and diaminopyrimidines, and beta-lactamase resistant penicillins. Broad-spectrum antibiotics showed a marked increase in their consumption from 11.50 DID in 2004 to 22.51 DID in 2016 whereas intermediate-spectrum antibiotics had only a slight increase in their consumption from 7.18 DID in 2004 to 8.51 DID in 2016, and narrow-spectrum antibiotics had a severe decline in their consumption from 0.006 DID in 2004 to 0.0003 DID in 2016. Conclusion There is an alarming increase in antibiotics consumption in Lebanon, particularly broad-spectrum antibiotics. This should be complemented with evidence on the determinants of antibiotic consumption such as prescriber and patient-related factors and drug promotional activities to minimize antibiotics overuse.

Changes in US Outpatient Antibiotic Prescriptions From 2011-2016

BACKGROUND

While antibiotics are life-saving drugs, their use is not without risk, including adverse events and antibiotic resistance. The majority of US antibiotic prescriptions are prescribed in outpatient settings, making outpatient antibiotic prescribing an important antibiotic stewardship target. The primary objective of this study was to describe trends in US outpatient oral antibiotic prescriptions from 2011-2016.

METHODS

We estimated annual oral antibiotic prescription rates using national prescription dispensing count data from IQVIA Xponent, divided by census estimates for 2011-2016. We calculated the ratio of broad- to narrow-spectrum prescriptions by dividing broad-spectrum prescription rates by narrow-spectrum prescription rates. We used Poisson models to estimate prevalence rate ratios, comparing 2011 and 2016 antibiotic prescription rates, and linear models to evaluate temporal trends throughout the study period.

RESULTS

Oral antibiotic prescription rates decreased 5%, from 877 prescriptions per 1000 persons in 2011 to 836 per 1000 persons in 2016. During this period, rates of prescriptions dispensed to children decreased 13%, while adult rates increased 2%. The ratio of broad- to narrow-spectrum antibiotics decreased from 1.62 in 2011 to 1.49 in 2016, driven by decreases in macrolides and fluoroquinolones. The proportion of prescriptions written by nurse practitioners and physician assistants increased during the study period; in 2016, these providers prescribed over one-quarter of all antibiotic prescriptions.

CONCLUSIONS

Outpatient antibiotic prescription rates, especially of broad-spectrum agents, have decreased in recent years. Clinicians who prescribe to adults, including nurse practitioners and physician assistants, are important targets for antibiotic stewardship.

Socioeconomic Status and Determinants of Pediatric Antibiotic Use

Introduction. Evidence suggests that early-life antibiotic use can alter gut microbiome, predisposing children to obesity. The obesity epidemic has a disproportionate effect on individuals from lower socioeconomic status (SES). Thus, this study aims to explore the link between SES and antibiotic use. Design. We performed a retrospective cohort study of all babies born at and receiving 2 or more outpatient visits at a large, suburban health system in Illinois (United States) between 2007 and 2017. We collected data on zip code as a proxy for SES and antibiotic use in the first year of life. We also obtained comorbid diagnosis codes, race/ethnicity, gender, and number of inpatient, outpatient, and emergency department visits. Results. A total of 7224 patients met our study criteria. Children from low-poverty areas received a lifetime average of 4.28 prescriptions, while those from high-poverty neighborhoods received an average of 3.31 prescriptions. This was statistically significant in our unadjusted analysis but not after adjusting for covariates. Children from high-poverty areas were significantly more likely to receive more antibiotics at 48 hours, 1 week, and 1 month of life in our unadjusted analysis, but not after adjusting for covariates. In our unadjusted and adjusted analyses, children from high-poverty areas were significantly more likely to have received antibiotics at 1 week of life. Conclusion. The relationship between SES and antibiotic use warrants further investigation to help elucidate possible causes of the disproportionate impact obesity has in low-income communities.

Association between tendon ruptures and use of fluoroquinolone, and other oral antibiotics: a 10-year retrospective study of 1 million US senior Medicare beneficiaries

OBJECTIVES

To assess the association of fluoroquinolone use with tendon ruptures compared with no fluoroquinolone and that of the four most commonly prescribed non-fluoroquinolone antibiotics in the USA.

DESIGN

Retrospective observational study.

SETTING

US seniors enrolled in the federal old-age, survivor's insurance programme.

PARTICIPANTS

1 009 925 Medicare fee-for-service beneficiaries and their inpatient, outpatient, prescription drug records were used.

INTERVENTIONS

Seven oral antibiotics, fluoroquinolones (ciprofloxacin, levofloxacin, moxifloxacin) and amoxicillin, amoxicillin-clavulanate, azithromycin and cephalexin.

PRIMARY AND SECONDARY OUTCOME MEASURES

All tendon ruptures combined, and three types of tendon ruptures by anatomic site, Achilles tendon rupture, rupture of rotator cuff and other tendon ruptures occurred in 2007-2016.

RESULTS

Of three fluoroquinolones, only levofloxacin exhibited a significant increased risk of tendon ruptures-16% (HR=1.16; 95% CI 1.06 to 1.28), and 120% (HR=2.20; 95% CI 1.50 to 3.24) for rotator cuff and Achilles tendon rupture, respectively, in the ≤30 days window. Ciprofloxacin (HR=0.96; 95% CI 0.89 to 1.03) and moxifloxacin (HR=0.59; 95% CI 0.37 to 0.93) exhibited no increased risk of tendon ruptures combined.Among the non-fluoroquinolone antibiotics, cephalexin exhibited increased risk of combined tendon ruptures (HR=1.31; 95% CI 1.22 to 1.41) and modest to large risks across all anatomic rupture sites (HRs 1.19-1.93) at ≤30 days window. Notably, the risk of levofloxacin never exceeded the risk of the non-fluoroquinolone, cephalexin in any comparison.

CONCLUSIONS

In our study, fluoroquinolones as a class were not associated with the increased risk of tendon ruptures. Neither ciprofloxacin nor moxifloxacin exhibited any risk for tendon ruptures. Levofloxacin did exhibit significant increased risk. Cephalexin with no reported effect on metalloprotease activity had an equal or greater risk than levofloxacin; so we question whether metalloprotease activity has any relevance to observed associations with tendon rupture. Confounding by indication bias may be more relevant and should be given more consideration as explanation for significant associations in observational studies of tendon rupture.

Decreased Overall and Inappropriate Antibiotic Prescribing in a Veterans Affairs Hospital Emergency Department following a Peer Comparison-Based Stewardship Intervention

Antibiotic prescribing is very common in emergency departments (EDs). Optimal stewardship intervention strategies in EDs are not well defined. We conducted a prospective, observational cohort study in a Veterans Affairs ED in which clinician education and monthly e-mail-based peer comparisons were directed against all oral antibiotic prescribing for discharged patients. Oral antibiotic prescriptions were compared in baseline (June 2016 to December 2017) and intervention (January to June 2018) periods using an interrupted time series regression model. Prescribing appropriateness was compared during January to June 2017 and the intervention period. During the intervention period, antibiotic prescriptions decreased monthly by 10.4 prescriptions per 1,000 ED visits (P = 0.07 [95% confidence interval {CI}, -21.7 to 1.0]). The relative decrease in the trend of antibiotic prescriptions during the intervention period compared to baseline was 9.9 prescriptions per 1,000 ED visits per month (P = 0.07 [95% CI, -20.9 to 1.0]). The intervention was associated with a significant decrease and increase in amoxicillin-clavulanate and cephalexin prescriptions, respectively (P < 0.001, P = 0.004). Decreasing trends in ciprofloxacin prescriptions during the baseline period were maintained during the intervention. Unnecessary antibiotic prescribing (i.e., antibiotic not indicated) decreased from 55.6% to 38.7% during the intervention (30.4% decrease, P = 0.003). Optimal antibiotic prescribing (i.e., antibiotics were indicated, and a guideline-concordant agent was prescribed for guideline-concordant duration) increased by 36% (21.6% to 29.3%, P = 0.12). A peer comparison-based stewardship intervention directed at ED clinicians was associated with reductions in overall and unnecessary oral antibiotic prescribing. There is potential to further improve antibiotic use as suboptimal prescribing remained common.

Rurality of Residence and Inappropriate Antibiotic Use for Acute Respiratory Infections Among Young Tennessee Children

Background

Antibiotic use is common for acute respiratory infections (ARIs) in children, but much of this use is inappropriate. Few studies have examined whether rurality of residence is associated with inappropriate antibiotic use. We examined whether rates of ARI-related inappropriate antibiotic use among children vary by rurality of residence.

Methods

We conducted a retrospective cohort study of children aged 2 months-5 years enrolled in Tennessee Medicaid between 2007 and 2017 and diagnosed with ARI in the outpatient setting. Study outcomes included ARI, ARI-related antibiotic use, and ARI-related inappropriate antibiotic use. Multivariable Poisson regression was used to measure associations between rurality of residence, defined by the US Census Bureau, and the rate of study outcomes, while accounting for other factors including demographics and underling comorbidities.

Results

A total of 805 332 children met selection criteria and contributed 1 840 048 person-years (p-y) of observation. Children residing in completely rural, mostly rural, and mostly urban counties contributed 70 369 (4%) p-y, 479 121 (26%) p-y, and 1 290 558 p-y (70%), respectively. Compared with children in mostly urban counties (238 per 1000 p-y), children in mostly rural (450 per 1000 p-y) and completely rural counties (468 per 1000 p-y) had higher rates of inappropriate antibiotic use (adjusted incidence rate ratio [aIRR] = 1.34, 95% confidence interval [CI] = 1.33-1.35 and aIRR = 1.33, 95% CI = 1.32-1.35, respectively).

Conclusions

Inappropriate antibiotic use is common among young children with ARI, with higher rates in rural compared with urban counties. These differences should inform targeted outpatient antibiotic stewardship efforts.

Upper Gastrointestinal Perforations: A Possible Danger of Antibiotic Overuse

BACKGROUND

The role of changes in gut microflora on upper gastrointestinal (UGI) perforations is not known. We conducted a retrospective case-control study to examine the relationship between antibiotic exposure-a proxy for microbiome modulation-and UGI perforations in a national sample.

METHODS

We queried a 5% random sample of Medicare (2009-2013) to identify patients ≥ 65 years old hospitalized with UGI (stomach or small intestine) perforations using International Classification of Diseases diagnosis codes. Cases with UGI perforations were matched with 4 controls, each based on age and sex. Exposure to outpatient antibiotics (0-30, 31-60, 61-90 days) prior to case patients' index hospitalization admission data was determined with Part D claims. Univariate and multivariable regression analyses were performed to evaluate the effect of antibiotic exposure on UGI perforation.

RESULTS

Overall, 504 cases and 2016 matched controls were identified. Compared to controls, more cases had antibiotic exposure 0-30 days (19% vs. 3%, p < 0.001) and 31-60 days (5% vs. 2%, p < 0.001) prior to admission. In adjusted analyses, antibiotic exposure 0-30 days prior to admission was associated with 6.8 increased odds of an UGI perforation (95% CI 4.8, 9.8); 31-60 days was associated with 1.9 increased odds (95% CI 1.1, 3.3); and 61-90 days was associated with 3.7 increased odds (95% CI 2.0, 6.9).

CONCLUSIONS

Recent outpatient antibiotic use, in particular in the preceding 30 days, is associated with UGI perforation among Medicare beneficiaries. Exposure to antibiotics, one of the most modifiable determinants of the microbiome, should be minimized in the outpatient setting.

Time Trends and Factors Associated with Antibiotic Prescribing in Swiss Primary Care (2008 to 2020)

Antibiotic resistance (ABR) is a major threat to public health, and the majority of antibiotics are prescribed in the outpatient setting, especially in primary care. Monitoring antibiotic consumption is one key measure in containing ABR, but Swiss national surveillance data are limited. We conducted a retrospective cross-sectional study to characterise the patterns of antibiotic prescriptions, assess the time trends, and identify the factors associated with antibiotic prescribing in Swiss primary care. Using electronic medical records data, we analysed 206,599 antibiotic prescriptions from 112,378 patients. Based on 27,829 patient records, respiratory (52.1%), urinary (27.9%), and skin (4.8%) infections were the commonest clinical indications for antibiotic prescribing. The most frequently prescribed antibiotics were broad-spectrum penicillins (BSP) (36.5%), fluoroquinolones (16.4%), and macrolides/lincosamides (13.8%). Based on the WHO AWaRe classification, antibiotics were 57.9% Core-Access and 41.7% Watch, 69% of which were quinolones and macrolides. Between 2008 and 2020, fluoroquinolones and macrolides/lincosamides prescriptions significantly declined by 53% and 51%; BSP prescriptions significantly increased by 54%. Increasing patients' age, volume, and employment level were significantly associated with antibiotic prescribing. Our results may inform future antibiotic stewardship interventions to improve antibiotic prescribing.

The role of "spillover" in antibiotic resistance

Antibiotic use is a key driver of antibiotic resistance. Understanding the quantitative association between antibiotic use and resulting resistance is important for predicting future rates of antibiotic resistance and for designing antibiotic stewardship policy. However, the use-resistance association is complicated by "spillover," in which one population's level of antibiotic use affects another population's level of resistance via the transmission of bacteria between those populations. Spillover is known to have effects at the level of families and hospitals, but it is unclear if spillover is relevant at larger scales. We used mathematical modeling and analysis of observational data to address this question. First, we used dynamical models of antibiotic resistance to predict the effects of spillover. Whereas populations completely isolated from one another do not experience any spillover, we found that if even 1% of interactions are between populations, then spillover may have large consequences: The effect of a change in antibiotic use in one population on antibiotic resistance in that population could be reduced by as much as 50%. Then, we quantified spillover in observational antibiotic use and resistance data from US states and European countries for three pathogen-antibiotic combinations, finding that increased interactions between populations were associated with smaller differences in antibiotic resistance between those populations. Thus, spillover may have an important impact at the level of states and countries, which has ramifications for predicting the future of antibiotic resistance, designing antibiotic resistance stewardship policy, and interpreting stewardship interventions.

Perceptions of the Benefits and Risks of Antibiotics Among Adult Patients and Parents With High Antibiotic Utilization

Background

Inappropriate antibiotic use is common. Understanding how patients view antibiotic risks and/or benefits could inform development of patient education materials and clinician communication strategies. We explored current knowledge, attitudes, and behaviors related to antibiotics among populations with high antibiotic use.

Methods

We conducted 12 focus groups with adult patients and parents across the United States by telephone in March 2017. Purposive sampling was used to identify participants with high antibiotic use. We transcribed the discussions verbatim and performed thematic analysis.

Results

We identified 4 major themes. First, participants expressed uncertainty regarding which clinical syndromes required antibiotics, and emotion often influenced their desire for antibiotics. Second, they had a limited understanding of antibiotic risks. Antibiotic resistance was viewed as the primary risk but was seen as a “distant, future” issue, whereas immediate adverse events, such as side effects, were minimized; however, patients expressed concern when told about the risk of serious adverse events. Third, they prioritized antibiotic benefits over risks in their decision-making, both due to an inaccurate estimation of antibiotic risks and/or benefits and a tendency to prioritize instant gratification. Fourth, most participants were willing to defer to their clinicians’ decisions about antibiotics, especially if their clinician provided symptomatic treatment and anticipatory guidance.

Conclusions

Patients have a limited understanding of antibiotic risks, potentially explaining why they are willing to try antibiotics even if it is unclear antibiotics will help. Educating patients on the potential antibiotic risks versus benefits, rather than just antibiotic resistance, may have a bigger impact on their decision-making.

Current update and future directions on gut microbiome and nephrolithiasis

The incidence of nephrolithiasis is increasing worldwide. Understanding how gut microbiome influences oxalate homeostasis has the potential to offer new strategies to prevent nephrolithiasis. The literature was reviewed to gather the evidence on the association between gut microbiome, hyperoxaluria and nephrolithiasis, and to identify the therapeutic interventions focused on the gut microbiome that could decrease hyperoxaluria and prevent nephrolithiasis. Gut microbiome is constituted by a plethora of microbiota including Oxalobacter formigenes (Oxf) and lactobacilli. Oxf can degrade dietary oxalate and induce enteral oxalate secretion. Animal studies suggested an association between oral Oxf supplementation and a decrease in hyperoxaluria. However, human studies have showed inconsistent results. Oral supplementation of lactobacilli did not show benefit in decreasing the hyperoxaluria. Antibiotic exposure, by affecting the gut microbiome, has been associated with an increase in nephrolithiasis. In vivo studies suggest fecal transplantation as a potential treatment option for reducing nephrolithiasis, but needs further evaluation in clinical studies. The current evidence suggests an association between gut microbiome and nephrolithiasis. However, the strategies focused on modulating gut microbiome for decreasing hyperoxaluria and preventing nephrolithiasis need further research. Judicious use of antibiotics in those predisposed to nephrolithiasis offers a preventative strategy for decreasing nephrolithiasis.

Efflux pump inhibitors: new updates

The discovery of antibiotics ought to have ended the issue of bacterial infections, but this was not the case as it has led to the evolution of various mechanisms of bacterial resistance against various antibiotics. The efflux pump remains one of the mechanisms through which organisms develop resistance against antibiotics; this is because organisms can extrude most of the clinically relevant antibiotics from the interior cell environment to the exterior environment via the efflux pumps. Efflux pumps are thought to contribute significantly to biofilm formation as highlighted by various studies. Therefore, the inhibition of these efflux pumps can be a potential way of improving the activity of antibiotics, particularly now that the discovery of novel antibiotics is becoming tedious. Efflux pump inhibitors (EPIs) are molecules that can inhibit efflux pumps; they have been considered potential therapeutic agents for rejuvenating the activity of antibiotics that have already lost their activity against bacteria. However, studies are yet to determine the specific substrates for such pumps; the effect of altered efflux activity of these pumps on biofilm formation is still being investigated. A clear knowledge of the involvement of efflux pumps in biofilm development could aid in developing new agents that can interfere with their function and help to prevent biofilms formation; thereby, improving the outcome of treatment strategies. This review focuses on the novel update of EPIs and discusses the evidence of the roles of efflux pumps in biofilm formation; the potential approaches towards overcoming the increasing problem of biofilm-based infections are also discussed.

Measuring Antibiotic Stewardship Programmes and Initiatives: An Umbrella Review in Primary Care Medicine and a Systematic Review of Dentistry

Antibiotic stewardship aims to tackle the global problem of drug-resistant infections by promoting the responsible use of antibiotics. Most antibiotics are prescribed in primary care and widespread overprescribing has been reported, including 80% in dentistry. This review aimed to identify outcomes measured in studies evaluating antibiotic stewardship across primary healthcare. An umbrella review was undertaken across medicine and a systematic review in dentistry. Systematic searches of Ovid Medline, Ovid Embase and Web of Science were undertaken. Two authors independently selected and quality assessed the included studies (using Critical Appraisal Skills Programme for the umbrella review and Quality Assessment Tool for Studies with Diverse Designs for the systematic review). Metrics used to evaluate antibiotic stewardship programmes and interventions were extracted and categorized. Comparisons between medical and dental settings were made. Searches identified 2355 medical and 2704 dental studies. After screening and quality assessment, ten and five studies, respectively, were included. Three outcomes were identified across both medical and dental studies: All focused on antibiotic usage. Four more outcomes were found only in medical studies: these measured patient outcomes, such as adverse effects. To evaluate antibiotic stewardship programmes and interventions across primary healthcare settings, measures of antibiotic use and patient outcomes are recommended.

A Baker's Dozen of Top Antimicrobial Stewardship Intervention Publications in 2019

Staying current on literature related to antimicrobial stewardship can be challenging given the ever-increasing number of published articles. The Southeastern Research Group Endeavor (SERGE-45) identified antimicrobial stewardship–related peer-reviewed literature that detailed an actionable intervention for 2019. The top 13 publications were selected using a modified Delphi technique. These manuscripts were reviewed to highlight the actionable intervention used by antimicrobial stewardship programs to provide key stewardship literature for teaching and training and to identify potential intervention opportunities within one’s institution.

Clinician and Patient Factors Influencing Treatment Decisions: Ethnographic Study of Antibiotic Prescribing and Operative Procedures in Out-of-Hours and General Dental Practices

Operative treatment is indicated for most toothache/dental abscesses, yet antibiotics instead of procedures are often prescribed. This ethnographic study aimed to identify clinician and patient factors influencing urgent dental care for adults during actual appointments; and to identify elements sensitive to context. Appointments were observed in out-of-hours and general dental practices. Follow-up interviews took place with dentists, dental nurses, and patients. Dentist and patient factors were identified through thematic analysis of observation records and appointment/interview transcripts. Dentist factors were based on a published list of factors influencing antibiotic prescribing for adults with acute conditions across primary health care and presented within the Capability-Opportunity-Motivation-Behaviour model. Contextually sensitive elements were revealed by comparing the factors between settings. In total, thirty-one dentist factors and nineteen patient factors were identified. Beliefs about antibiotics, goals for the appointment and access to dental services were important for both dentists and patients. Dentist factors included beliefs about the lifetime impact of urgent dental procedures on patients. Patient factors included their communication and negotiation skills. Contextual elements included dentists’ concerns about inflicting pain on regular patients in general dental practice; and patients’ difficulties accessing care to complete temporary treatment provided out of hours. This improved understanding of factors influencing shared decisions about treatments presents significant opportunity for new, evidence-based, contextually sensitive antibiotic stewardship interventions.

Outpatient Antibiotic Dispensing for the Population with Government Health Insurance in Syria in 2018-2019

Little is known about antibiotic uses at the population level in Syria. The aim of our study is to present outpatient antibiotic dispensing (OAD) patterns and rates for patients with health insurance in the parts of Syria that are controlled by the Syrian government using different indicators. Outpatient data on all dispensed antibiotics for 81,314 adults with health insurance were obtained and stratified according to age, sex, governorate and annual season. OAD was mainly expressed as the number of defined daily doses (DDDs) per 1000 people per day (DID). OAD patterns were assessed according to the anatomical therapeutic classification (ATC) and the Access, Watch and Reserve (AWaRe) classification. OAD was 20.13 DID. Amoxicillin/clavulanic acid and clarithromycin were the most dispensed antibiotics (5.76 and 4.4 DID, respectively). Overall, a predominant consumption of broad-spectrum antibiotics was noted. The Watch group of the AWaRe classification had the biggest percentage of OAD (13.26 DID), followed by the Access and the Reserve groups (6.55 and 0.17 DID, respectively). There was a significant difference in OAD between the sex and age groups. The seasonal and regional variations in OAD were also significant. Broad-spectrum antibiotics dispensing was high compared to other studies from different countries. These results are concerning, as they can contribute to antibiotic resistance.

Reducing Antibiotic Prescribing in Primary Care for Respiratory Illness

BACKGROUND

One-third of outpatient antibiotic prescriptions for pediatric acute respiratory tract infections (ARTIs) are inappropriate. We evaluated a distance learning program's effectiveness for reducing outpatient antibiotic prescribing for ARTI visits.

METHODS

In this stepped-wedge clinical trial run from November 2015 to June 2018, we randomly assigned 19 pediatric practices belonging to the Pediatric Research in Office Settings Network or the NorthShore University HealthSystem to 4 wedges. Visits for acute otitis media, bronchitis, pharyngitis, sinusitis, and upper respiratory infection for children 6 months to <11 years old without recent antibiotic use were included. Clinicians received the intervention as 3 program modules containing online tutorials and webinars on evidence-based communication strategies and antibioti c prescribing, booster video vignettes, and individualized antibiotic prescribing feedback reports over 11 months. The primary outcome was overall antibiotic prescribing rates for all ARTI visits. Mixed-effects logistic regression compared prescribing rates during each program module and a postintervention period to a baseline control period. Odds ratios were converted to adjusted rate ratios (aRRs) for interpretability.

RESULTS

Among 72 723 ARTI visits by 29 762 patients, intention-to-treat analyses revealed a 7% decrease in the probability of antibiotic prescribing for ARTI overall between the baseline and postintervention periods (aRR 0.93; 95% confidence interval [CI], 0.90-0.96). Second-line antibiotic prescribing decreased for streptococcal pharyngitis (aRR 0.66; 95% CI, 0.50-0.87) and sinusitis (aRR 0.59; 95% CI, 0.44-0.77) but not for acute otitis media (aRR 0.93; 95% CI, 0.83-1.03). Any antibiotic prescribing decreased for viral ARTIs (aRR 0.60; 95% CI, 0.51-0.70).

CONCLUSIONS

This program reduced antibiotic prescribing during outpatient ARTI visits; broader dissemination may be beneficial.

Prevalence of and rationale for antimicrobial prescription during ambulatory care visits in Japan: a prospective, multicentre, cross-sectional study

OBJECTIVE

To determine the rate of outpatient antimicrobial use and the rationale for antimicrobial prescription.

DESIGN

A prospective, multicentre, cross-sectional study.

SETTING

Ambulatory care settings at community general hospitals.

PARTICIPANTS

A total of 1972 consecutive ambulatory visits by 1952 patients were included from 2 February 2020 to 13 February 2020. Visits resulting in hospital admission and regularly scheduled visits were excluded.

MAIN OUTCOME MEASURES

The primary outcome was the proportion of ambulatory visits resulting in antimicrobial drug prescriptions. The secondary outcomes were the reasons for antimicrobial drug prescription and the proportion of unnecessary antimicrobial prescriptions among all antimicrobial drugs used for treatment.

RESULTS

The mean patient age was 53.8 (SD 25.8) years old, and the proportion of women was 52.6%. A total of 162 antimicrobial drugs were prescribed in 153 (7.8%) visits. The most common antimicrobial drugs were penicillins (n=48, 29.6%), followed by third-generation cephalosporins (n=35, 21.6%) and quinolones (n=20, 12.4%). Among all the antimicrobial drugs prescribed, 125 (77.2%), 18 (11.1%) and 11 (6.8%) were used for infection treatment, wound prophylaxis and surgical prophylaxis, respectively. Of the 125 antimicrobial drugs used for infection treatment, 60 (48.0%) were judged to be unnecessary.

CONCLUSIONS

One in every 13 ambulatory visits resulted in antimicrobial use in Japan. Three-fourths of the prescribed antimicrobial drugs were used for infection treatment, but approximately half of those drugs may have been unnecessary. Further efforts to reduce unnecessary antimicrobial drug use are needed.

TRIAL REGISTRATION NUMBER

UMIN000039360.

Expanding the Spectrum of Antibiotics Capable of Killing Multidrug-Resistant Staphylococcus aureus and Pseudomonas aeruginosa

Infections from antibiotic-resistant Staphylococcus aureus and Pseudomonas aeruginosa are a serious threat because reduced antibiotic efficacy complicates treatment decisions and prolongs the disease state in many patients. To expand the arsenal of treatments against antimicrobial-resistant (AMR) pathogens, 600-Da branched polyethylenimine (BPEI) can overcome antibiotic resistance mechanisms and potentiate β-lactam antibiotics against Gram-positive bacteria. BPEI binds cell-wall teichoic acids and disables resistance factors from penicillin binding proteins PBP2a and PBP4. This study describes a new mechanism of action for BPEI potentiation of antibiotics generally regarded as agents effective against Gram-positive pathogens but not Gram-negative bacteria. 600-Da BPEI is able to reduce the barriers to drug influx and facilitate the uptake of a non-β-lactam co-drug, erythromycin, which targets the intracellular machinery. Also, BPEI can suppress production of the cytokine interleukin IL-8 by human epithelial keratinocytes. This enables BPEI to function as a broad-spectrum antibiotic potentiator, and expands the opportunities to improve drug design, antibiotic development, and therapeutic approaches against pathogenic bacteria, especially for wound care.

Evaluation of the Cost-effectiveness of Infection Control Strategies to Reduce Hospital-Onset Clostridioides difficile Infection

Importance

Clostridioides difficile infection is the most common hospital-acquired infection in the United States, yet few studies have evaluated the cost-effectiveness of infection control initiatives targeting C difficile.

Objective

To compare the cost-effectiveness of 9 C difficile single intervention strategies and 8 multi-intervention bundles.

Design, Setting, and Participants

This economic evaluation was conducted in a simulated 200-bed tertiary, acute care, adult hospital. The study relied on clinical outcomes from a published agent-based simulation model of C difficile transmission. The model included 4 agent types (ie, patients, nurses, physicians, and visitors). Cost and utility estimates were derived from the literature.

Interventions

Daily sporicidal cleaning, terminal sporicidal cleaning, health care worker hand hygiene, patient hand hygiene, visitor hand hygiene, health care worker contact precautions, visitor contact precautions, C difficile screening at admission, and reduced intrahospital patient transfers.

Main Outcomes and Measures

Cost-effectiveness was evaluated from the hospital perspective and defined by 2 measures: cost per hospital-onset C difficile infection averted and cost per quality-adjusted life-year (QALY).

Results

In this agent-based model of a simulated 200-bed tertiary, acute care, adult hospital, 5 of 9 single intervention strategies were dominant, reducing cost, increasing QALYs, and averting hospital-onset C difficile infection compared with baseline standard hospital practices. They were daily cleaning (most cost-effective, saving $358 268 and 36.8 QALYs annually), health care worker hand hygiene, patient hand hygiene, terminal cleaning, and reducing intrahospital patient transfers. Screening at admission cost $1283/QALY, while health care worker contact precautions and visitor hand hygiene interventions cost $123 264/QALY and $5 730 987/QALY, respectively. Visitor contact precautions was dominated, with increased cost and decreased QALYs. Adding screening, health care worker hand hygiene, and patient hand hygiene sequentially to the daily cleaning intervention formed 2-pronged, 3-pronged, and 4-pronged multi-intervention bundles that cost an additional $29 616/QALY, $50 196/QALY, and $146 792/QALY, respectively.

Conclusions and Relevance

The findings of this study suggest that institutions should seek to streamline their infection control initiatives and prioritize a smaller number of highly cost-effective interventions. Daily sporicidal cleaning was among several cost-saving strategies that could be prioritized over minimally effective, costly strategies, such as visitor contact precautions.

Variation in antibiotic prescription rates in febrile children presenting to emergency departments across Europe (MOFICHE): A multicentre observational study

BACKGROUND

The prescription rate of antibiotics is high for febrile children visiting the emergency department (ED), contributing to antimicrobial resistance. Large studies at European EDs covering diversity in antibiotic and broad-spectrum prescriptions in all febrile children are lacking. A better understanding of variability in antibiotic prescriptions in EDs and its relation with viral or bacterial disease is essential for the development and implementation of interventions to optimise antibiotic use. As part of the PERFORM (Personalised Risk assessment in Febrile illness to Optimise Real-life Management across the European Union) project, the MOFICHE (Management and Outcome of Fever in Children in Europe) study aims to investigate variation and appropriateness of antibiotic prescription in febrile children visiting EDs in Europe.

METHODS AND FINDINGS

Between January 2017 and April 2018, data were prospectively collected on febrile children aged 0-18 years presenting to 12 EDs in 8 European countries (Austria, Germany, Greece, Latvia, the Netherlands [n = 3], Spain, Slovenia, United Kingdom [n = 3]). These EDs were based in university hospitals (n = 9) or large teaching hospitals (n = 3). Main outcomes were (1) antibiotic prescription rate; (2) the proportion of antibiotics that were broad-spectrum antibiotics; (3) the proportion of antibiotics of appropriate indication (presumed bacterial), inappropriate indication (presumed viral), or inconclusive indication (unknown bacterial/viral or other); (4) the proportion of oral antibiotics of inappropriate duration; and (5) the proportion of antibiotics that were guideline-concordant in uncomplicated urinary and upper and lower respiratory tract infections (RTIs). We determined variation of antibiotic prescription and broad-spectrum prescription by calculating standardised prescription rates using multilevel logistic regression and adjusted for general characteristics (e.g., age, sex, comorbidity, referral), disease severity (e.g., triage level, fever duration, presence of alarming signs), use and result of diagnostics, and focus and cause of infection. In this analysis of 35,650 children (median age 2.8 years, 55% male), overall antibiotic prescription rate was 31.9% (range across EDs: 22.4%-41.6%), and among those prescriptions, the broad-spectrum antibiotic prescription rate was 52.1% (range across EDs: 33.0%-90.3%). After standardisation, differences in antibiotic prescriptions ranged from 0.8 to 1.4, and the ratio between broad-spectrum and narrow-spectrum prescriptions ranged from 0.7 to 1.8 across EDs. Standardised antibiotic prescription rates varied for presumed bacterial infections (0.9 to 1.1), presumed viral infections (0.1 to 3.3), and infections of unknown cause (0.1 to 1.8). In all febrile children, antibiotic prescriptions were appropriate in 65.0% of prescriptions, inappropriate in 12.5% (range across EDs: 0.6%-29.3%), and inconclusive in 22.5% (range across EDs: 0.4%-60.8%). Prescriptions were of inappropriate duration in 20% of oral prescriptions (range across EDs: 4.4%-59.0%). Oral prescriptions were not concordant with the local guideline in 22.3% (range across EDs: 11.8%-47.3%) of prescriptions in uncomplicated RTIs and in 45.1% (range across EDs: 11.1%-100%) of prescriptions in uncomplicated urinary tract infections. A limitation of our study is that the included EDs are not representative of all febrile children attending EDs in that country.

CONCLUSIONS

In this study, we observed wide variation between European EDs in prescriptions of antibiotics and broad-spectrum antibiotics in febrile children. Overall, one-third of prescriptions were inappropriate or inconclusive, with marked variation between EDs. Until better diagnostics are available to accurately differentiate between bacterial and viral aetiologies, implementation of antimicrobial stewardship guidelines across Europe is necessary to limit antimicrobial resistance.

Patterns of Antibiotic Prescription in Colombia: Are There Differences between Capital Cities and Municipalities?

The use of antibiotics is the most important modifiable risk factor for the development of microorganism resistance. A cross-sectional study of outpatients receiving antibiotic prescriptions registered in a population database in Colombia was conducted. The characteristics of the consumption in capital cities and small municipalities was studied and the AWaRe classification was used. AWaRe classifies antibiotics into three stewardship groups: Access, Watch and Reserve, to emphasize the importance of their optimal use and potential harms of antimicrobial resistance. A total of 182,397 patients were prescribed an antibiotic; the most common were penicillins (38.6%), cephalosporins (30.2%) and fluoroquinolones (10.9%). ‘Access’ antibiotics (86.4%) were the most frequently prescribed, followed by ‘Watch’ antibiotics (17.0%). Being 18 or older, being male, living in a municipality, having one or more comorbidities and urinary, respiratory or gastrointestinal disorders increased the probability of receiving ‘Watch’ or ‘Reserve’ antibiotics. Penicillin and urinary antiseptic prescriptions predominated in cities, while cephalosporin and fluoroquinolone prescriptions predominated in municipalities. This analysis showed that the goal set by the WHO Access of mainly using Access antibiotics is being met, although the high use of Watch antibiotics in municipalities should be carefully studied to determine if it is necessary to design specific campaigns to improve antibiotics use.

Prescription and indications for the use of fluoroquinolones in a group of outpatients in Colombia

Introducción.

Existen evidencias sobre el uso indiscriminado de antibióticos en el tratamiento de diversas enfermedades.

Objetivo.

Determinar los patrones de prescripción y de indicaciones de uso de las fluoroquinolonas en un grupo de pacientes ambulatorios en Colombia.

Materiales y métodos.

Se llevó a cabo un estudio descriptivo farmacoepidemiológico del tipo de prescripción e indicaciones de uso a partir de una base de datos poblacionales que incluía pacientes con prescripciones ambulatorias de fluoroquinolonas entre mayo y octubre de 2018. Se recabó la información sobre las variables sociodemográficas, farmacológicas y clínicas (diagnóstico según la Clasificación Internacional de Enfermedades, versión 10) y se estableció la proporción del uso de fluoroquinolonas en indicaciones aprobadas y no aprobadas por las agencias reguladoras.

Resultados.

Se identificaron 23.373 pacientes que habían recibido fluoroquinolonas; su edad media era de 47,9 ± 18,1 años y 15.767 eran mujeres (67,5 %). La ciprofloxacina fue el medicamento más prescrito (n=19.328; 82,7 %), seguida de la norfloxacina (n=3.076; 13,2 %), la levofloxacina (n=573; 2,5 %) y la moxifloxacina (n=394; 1,7 %). Las principales indicaciones fueron la infección de las vías urinarias en sitio no especificado (n=10.777; 46,1 %), la diarrea y la gastroenteritis de presunto origen infeccioso (n=3.077, 13,2 %) y la cistitis aguda (n=956; 4,2 %). El 76 % (n=17.759) de las prescripciones correspondía a indicaciones aprobadas y el resto a usos no aprobados, como la rinofaringits o las infecciones de tejidos blandos. El ser hombre (odds ratio, OR=1,26; IC_95%: 1,18-1,34) y tener menos de 35 años (OR=1,92; IC_95%:1,48-1,50) se asociaron con una mayor probabilidad de uso de fluoroquinolonas en indicaciones no aprobadas.

Conclusión.

Las fluoroquinolonas, en particular la ciprofloxacina, se están prescribiendo especialmente a mujeres con infecciones de las vías urinarias, pero hasta la cuarta parte de los pacientes las recibieron para usos no aprobados por las agencias reguladoras.

Modeling inpatient and outpatient antibiotic stewardship interventions to reduce the burden of Clostridioides difficile infection in a regional healthcare network

Antibiotic exposure can lead to unintended outcomes, including drug-drug interactions, adverse drug events, and healthcare-associated infections like Clostridioides difficile infection (CDI). Improving antibiotic use is critical to reduce an individual's CDI risk. Antibiotic stewardship initiatives can reduce inappropriate antibiotic prescribing (e.g., unnecessary antibiotic prescribing, inappropriate antibiotic selection), impacting both hospital (healthcare)-onset (HO)-CDI and community-associated (CA)-CDI. Previous computational and mathematical modeling studies have demonstrated a reduction in CDI incidence associated with antibiotic stewardship initiatives in hospital settings. Although the impact of antibiotic stewardship initiatives in long-term care facilities (LTCFs), including nursing homes, and in outpatient settings have been documented, the effects of specific interventions on CDI incidence are not well understood. We examined the relative effectiveness of antibiotic stewardship interventions on CDI incidence using a geospatially explicit agent-based model of a regional healthcare network in North Carolina. We simulated reductions in unnecessary antibiotic prescribing and inappropriate antibiotic selection with intervention scenarios at individual and network healthcare facilities, including short-term acute care hospitals (STACHs), nursing homes, and outpatient locations. Modeled antibiotic prescription rates were calculated using patient-level data on antibiotic length of therapy for the 10 modeled network STACHs. By simulating a 30% reduction in antibiotics prescribed across all inpatient and outpatient locations, we found the greatest reductions on network CDI incidence among tested scenarios, namely a 17% decrease in HO-CDI incidence and 7% decrease in CA-CDI. Among intervention scenarios of reducing inappropriate antibiotic selection, we found a greater impact on network CDI incidence when modeling this reduction in nursing homes alone compared to the same intervention in STACHs alone. These results support the potential importance of LTCF and outpatient antibiotic stewardship efforts on network CDI burden and add to the evidence that a coordinated approach to antibiotic stewardship across multiple facilities, including inpatient and outpatient settings, within a regional healthcare network could be an effective strategy to reduce network CDI burden.

Communicating Antibiotic Stewardship: Emotional Responses and Their Impact on Adherence

Although watchful watching has been recommended as a means of reducing unnecessary use of antibiotics, nonadherence has frequently been observed. Drawing from appraisal theories of emotion, this study (n = 579) examined (a) the factors that shape pediatric caregivers' emotional experiences in the medical contexts and (b) the influence of emotions on (non)adherence behavioral intentions. Caregivers reported more intense negative emotions and less intense positive emotions following watchful waiting advice versus receiving an antibiotic prescription. The differences were mostly driven by false beliefs about antibiotics' effectiveness. Emotional responses predicted intentions to adhere to watchful waiting advice (e.g., counterargue and seek another healthcare provider), with anger being the most consistent determinant of these outcomes. Improving antibiotic stewardship can be achieved by educational efforts to correct false beliefs and by training healthcare providers to manage caregiver emotions.

The speed of adoption of new drugs and prescription volume after the amendments in reimbursement coverage: the case of non-vitamin K antagonist oral anticoagulants in South Korea

Background

The speed of adoption of new drugs and frequencies of substitutions leads to changes in health care expenditures as well as patient outcomes. In this study, we aim to understand the speed of adoption of new drugs and their prescription volume in health care institutions and evaluate the impact of policy options to manage pharmaceutical expenditure.

Methods

We conducted a retrospective cohort study of health care institutions prescribing NOACs, including Apixaban, Dabigatran, and Rivaroxaban, to address the speed of adoption and their substitution from October 1, 2010, through December 31, 2015, using the National Health Insurance Service-National Sample Cohort. Two threshold time points, including the extension of reimbursement with the need for the letter of opinion and the withdrawal of the letter of opinion, were noted in this study. Then, we applied a survival analysis to elucidate factors that affected the speed of adoption of NOACs, and interrupted time series analysis to estimate the effect of amendments in reimbursement coverage in prescription volume.

Results

Among 934 health care institutions in a study population, 334 institutions (36%) had prescribed NOACs at least one time during the study period, indicating that health care institutions were conservative in adopting new drugs. However, the speed of adoption was related to the characteristics of health care institution. We also found that prescriptions of NOACs before the withdrawal of the need for the letter of opinion were marginal, and the prescription volume of NOACs was significantly increased after the withdrawal of a letter of opinion.

Conclusions

Health care institutions were conservative in adopting new drugs, and the speed of adoption is not closely related to an increased prescription volume in the short run. Thus, policies that are centered on managing pharmaceutical expenditure should be devised with considering the impact of introducing new drugs in the long run. A letter of opinion, which was devised to manage prescriptions of NOACs, was effective in managing pharmaceutical expenditures in health care institutions, particularly for tertiary institutions. Conversely, the withdrawal of the need for the letter of opinion should be implemented with caution.

FDA collaboration to improve safe use of fluoroquinolone antibiotics: an ex post facto matched control study of targeted short-form messaging and online education served to high prescribers

Objective:

This ex post facto matched control study was conducted to evaluate the effect of targeted short-form messages or continuing medical education (CME) on fluoroquinolone prescribing among high prescribers.

Methods:

A total of 11,774 Medscape healthcare provider (HCP) members prescribing high volumes of fluoroquinolones were randomized into three segments to receive one of three unique targeted short-form messages, each delivered via email, web alerts, and mobile alerts. Some HCPs receiving targeted short-form messages also participated in CME on fluoroquinolone prescribing. A fourth segment of HCPs participated in CME only. Test HCPs were matched to third-party-provider prescriber data to identify control HCPs. We used prescriber data to determine new prescription volume; percentage (%) of HCPs with reduced prescribing; new prescription volume for acute bacterial sinusitis (ABS), uncomplicated urinary tract infection (uUTI), and acute bacterial exacerbations of chronic bronchitis in those with chronic obstructive pulmonary disease (ABECB-COPD). Open rates for emailed targeted short-form messages were also measured.

Results:

Targeted short-form messages and CME each resulted in significant new prescription volume reduction versus control. Combining targeted short-form messages with CME yielded the greatest percentage of test HCPs with reduced prescribing (80.1%) versus controls (76.2%; p<0.0001). New prescription volume decreased significantly for uUTI and ABS following exposure to targeted short-form messages, CME, or both. Targeted short-form messages containing comparative prescribing information with or without clinical context were opened at slightly higher rates (10.8% and 10.6%, respectively) than targeted short-form messages containing clinical context alone (9.1%).

Conclusions:

Targeted short-form messages and CME, alone and in combination, are associated with reduced oral fluoroquinolone prescribing among high prescribers.

Overcoming Multidrug Resistance and Biofilms of Pseudomonas aeruginosa with a Single Dual-Function Potentiator of β-Lactams

Clinicians prescribe hundreds of millions of β-lactam antibiotics to treat the majority of patients presenting with bacterial infections. Patient outcomes are positive unless resistant bacteria, such as Pseudomonas aeruginosa (P. aeruginosa), are present. P. aeruginosa has both intrinsic and acquired antibiotic resistance, making clinical management of infection a real challenge, particularly when these bacteria are sequestered in biofilms. These problems would be alleviated if, upon the initial presentation of bacterial infection symptoms, clinicians were able to administer an antibiotic that kills both susceptible and otherwise resistant bacteria and eradicates biofilms. As the most common class of antibiotics, β-lactams could be used in a new drug if the leading causes of β-lactam antibiotic resistance, permeation barriers from lipopolysaccharide, efflux pumps, and β-lactamase enzymes, were also defeated. Against P. aeruginosa and their biofilms, the potency of β-lactam antibiotics is restored with 600 Da branched polyethylenimine (600 Da BPEI). Checkerboard assays using microtiter plates demonstrate the potentiation of piperacillin, cefepime, Meropenem, and erythromycin antibiotics. Growth curves demonstrate that only a combination of 600 Da BPEI and piperacillin produces growth inhibition against antibiotic resistant P. aeruginosa. Scanning electron microscopy (SEM) was used to confirm that the combination treatment leads to abnormal P. aeruginosa morphology. Data collected with isothermal titration calorimetry and fluorescence spectroscopy demonstrate a mechanism of action in which potentiation at low concentrations of 600 Da BPEI reduces diffusion barriers from lipopolysaccharides without disrupting the outer membrane itself. Coupled with the ability to overcome a reduction in antibiotic activity created by biofilm exopolymers, targeting anionic sites on lipopolysaccharides and biofilm exopolysaccharides with the same compound provides new opportunities to counter the rise of multidrug-resistant infections.

Perturbations of the Gut Microbiome and Metabolome in Children with Calcium Oxalate Kidney Stone Disease

BACKGROUND

The relationship between the composition and function of gut microbial communities and early-onset calcium oxalate kidney stone disease is unknown.

METHODS

We conducted a case-control study of 88 individuals aged 4-18 years, which included 44 individuals with kidney stones containing ≥50% calcium oxalate and 44 controls matched for age, sex, and race. Shotgun metagenomic sequencing and untargeted metabolomics were performed on stool samples.

RESULTS

Participants who were kidney stone formers had a significantly less diverse gut microbiome compared with controls. Among bacterial taxa with a prevalence >0.1%, 31 taxa were less abundant among individuals with nephrolithiasis. These included seven taxa that produce butyrate and three taxa that degrade oxalate. The lower abundance of these bacteria was reflected in decreased abundance of the gene encoding butyryl-coA dehydrogenase (P=0.02). The relative abundance of these bacteria was correlated with the levels of 18 fecal metabolites, and levels of these metabolites differed in individuals with kidney stones compared with controls. The oxalate-degrading bacterial taxa identified as decreased in those who were kidney stone formers were components of a larger abundance correlation network that included Eggerthella lenta and several Lactobacillus species. The microbial (α) diversity was associated with age of stone onset, first decreasing and then increasing with age. For the individuals who were stone formers, we found the lowest α diversity among individuals who first formed stones at age 9-14 years, whereas controls displayed no age-related differences in diversity.

CONCLUSIONS

Loss of gut bacteria, particularly loss of those that produce butyrate and degrade oxalate, associates with perturbations of the metabolome that may be upstream determinants of early-onset calcium oxalate kidney stone disease.

Prevalence and Determinants of Antibiotic Consumption in the Elderly during 2006-2017

Elderly people are a particularly important population with regard to antibiotic overuse, using around 50% more antibiotics per capita than younger adults. The aim of this study was to analyze the prevalence, associated factors and evolution over time of antibiotic consumption among the Spanish population aged ≥ 65 years from 2006 to 2017. A descriptive cross-sectional study was conducted using data from the Spanish National Health Survey in 2006, 2011/2012 and 2017, and from the European Health Survey in Spain in 2009 and 2014. The sample consisted of 26,891 non-institutionalized individuals ≥ 65 years. Antibiotic consumption was the dependent variable, and sociodemographic variables, lifestyle habits and health status were analyzed using a logistic regression model. The prevalence of antibiotic consumption was 4.94%, with a marked increase from 2006 (4.64%) to 2017 (5.81%) (p < 0.0001). Higher antibiotic consumption was associated with poor or very poor self-perceived health status, no polypharmacy and not having been in hospital during the previous twelve months, while a lower consumption was linked to being limited but not severely due to a health problem and not being at all limited.

Antibiotic Prescribing Patterns for Acute Otitis Media for Children 2 Years and Older

OBJECTIVE

To determine the frequency that non-first-line antibiotics, safety-net antibiotic prescriptions (SNAPS), and longer than recommended durations of antibiotics were prescribed for children ≥2 years of age with acute otitis media and examine patient and system level factors that contributed to these outcomes.

STUDY DESIGN

Children age ≥2 years with acute otitis media seen at Denver Health Medical Center outpatient locations from January to December 2018 were included. The percentages of patients who received first-line antibiotics, SNAPs, and recommended durations of antibiotics were determined. Factors associated with non-first-line and longer than recommended antibiotic durations were evaluated using multivariate logistic regression modeling.

RESULTS

Of the 1025 visits evaluated, 98.0% were prescribed an antibiotic; only 4.5% of antibiotics were SNAPs. Non-first-line antibiotics were prescribed to 18.8% of patients. Most antibiotic durations (94.1%) were longer than the institution recommended 5 days and 54.3% were ≥10 days. Private insurance was associated with non-first-line antibiotics (aOR, 1.89; 95% CI, 1; 14-3.14, P = .01). Patients who were younger (2-5 years; aOR 2.01; 95% CI, 1.32-3.05; P < .001) or seen in emergency/urgent care sites (aOR, 1.73; 95% CI, 1.26-2.38; P < .001) were more likely to receive ≥10 days of antibiotic compared with those in pediatric clinics.

CONCLUSIONS

Antibiotic stewardship interventions that emphasize the duration of antibiotic therapy as well as the use of SNAPs or observation may be higher yield than those focusing on first-line therapy alone. Numerous system and patient level factors are associated with off-guideline prescribing.

Antibiotic Prescribing Variability in a Large Urgent Care Network: A New Target for Outpatient Stewardship

Improving antibiotic prescribing in outpatient settings is a public health priority. In the United States, urgent care (UC) encounters are increasing and have high rates of inappropriate antibiotic prescribing. Our objective was to characterize antibiotic prescribing practices during UC encounters, with a focus on respiratory tract conditions. This was a retrospective cohort study of UC encounters in the Intermountain Healthcare network. Among 1.16 million UC encounters, antibiotics were prescribed during 34% of UC encounters and respiratory conditions accounted for 61% of all antibiotics prescribed. Of respiratory encounters, 50% resulted in antibiotic prescriptions, yet the variability at the level of the provider ranged from 3% to 94%. Similar variability between providers was observed for respiratory conditions where antibiotics were not indicated and in first-line antibiotic selection for sinusitis, otitis media, and pharyngitis. These findings support the importance of developing antibiotic stewardship interventions specifically targeting UC settings.

Patient and provider characteristics and outcomes associated with outpatient antibiotic overuse in acute adult bronchitis

Nonbacterial acute bronchitis leads to many outpatient clinic visits in the US that result in an antibiotic prescription. Understanding antibiotic prescribing patterns and their clinical consequences will help improve antimicrobial stewardship efforts. A retrospective chart review was conducted to identify any correlations between patient and provider characteristics with antibiotic use in adult acute bronchitis (AAB) and to compare the clinical outcomes and rates of health care utilization between those who did and did not receive antibiotics. Study participants included adults with uncomplicated AAB seen by family medicine or internal medicine, specialty, and mid-level practitioners in a Baylor Scott & White Health outpatient facility. Phase 1 investigated whether prescribing rates varied by provider- or patient-level characteristics. Phase 2 compared clinical outcomes and health care utilization between patients who received an antibiotic versus those who did not receive an antibiotic for AAB. Among 35,383 visits for AAB, 81.4% resulted in a prescription for an antibiotic. Physicians >35 years of age and internal and family medicine physicians were more likely to prescribe antibiotics. Health care utilization rates did not differ between cohorts. The number of Clostridium difficile events was negligible.

Discovery and Characterization of the Antimetabolite Action of Thioacetamide-Linked 1,2,3-Triazoles as Disruptors of Cysteine Biosynthesis in Gram-Negative Bacteria

Increasing rates of drug-resistant Gram-negative (GN) infections, combined with a lack of new GN-effective antibiotic classes, are driving the need for the discovery of new agents. Bacterial metabolism represents an underutilized mechanism of action in current antimicrobial therapies. Therefore, we sought to identify novel antimetabolites that disrupt key metabolic pathways and explore the specific impacts of these agents on bacterial metabolism. This study describes the successful application of this approach to discover a new series of chemical probes, N-(phenyl)thioacetamide-linked 1,2,3-triazoles (TAT), that target cysteine synthase A (CysK), an enzyme unique to bacteria that is positioned at a key juncture between several fundamental pathways. The TAT class was identified using a high-throughput screen against Escherichia coli designed to identify modulators of pathways related to folate biosynthesis. TAT analog synthesis demonstrated a clear structure-activity relationship, and activity was confirmed against GN antifolate-resistant clinical isolates. Spontaneous TAT resistance mutations were tracked to CysK, and mode of action studies led to the identification of a false product formation mechanism between the CysK substrate O-acetyl-l-serine and the TATs. Global transcriptional responses to TAT treatment revealed that these antimetabolites impose substantial disruption of key metabolic networks beyond cysteine biosynthesis. This study highlights the potential of antimetabolite drug discovery as a promising approach to the discovery of novel GN antibiotics and the pharmacological promise of TAT CysK probes.

Barriers and facilitators to the uptake of an antimicrobial stewardship program in primary care: A qualitative study

The overuse of antimicrobials in primary care can be linked to an increased risk of antimicrobial-resistant bacteria for individual patients. Although there are promising signs of the benefits associated with Antimicrobial Stewardship Programs (ASPs) in hospitals and long-term care settings, there is limited knowledge in primary care settings and how to implement ASPs in these settings is unclear. In this context, a qualitative study was undertaken to explore the perceptions of primary care prescribers of the usefulness, feasibility, and experiences associated with the implementation of a pilot community-focused ASP intervention in three primary care clinics. Qualitative interviews were conducted with primary care clinicians, including local ASP champions, prescribers, and other primary health care team members, while they participated in an ASP initiative within one of three primary care clinics. An iterative conventional content analyses approach was used to analyze the transcribed interviews. Themes emerged around the key enablers and barriers associated with ASP implementation. Study findings point to key insights relevant to the scalability of community ASP activities with primary care providers.

The appropriateness of antimicrobial use in the outpatient clinics of three hospitals in the Netherlands

OBJECTIVES

Antimicrobial Stewardship Programs commonly have an in-hospital focus. Little is known about the quality of antimicrobial use in hospital outpatient clinics. We investigated the extent and appropriateness of antimicrobial prescriptions in the outpatient clinics of three hospitals.

METHODS

From June 2018 to January 2019, we performed ten point prevalence surveys in outpatient clinics of one university hospital and two large teaching hospitals. All prophylactic and therapeutic prescriptions were retrieved from the electronic medical records. Appropriateness was defined as being in accordance with guidelines. Furthermore, we investigated the extent to which the dose was adjusted to renal function and documentation of an antibiotic plan in the case notes.

RESULTS

We retrieved 720 prescriptions for antimicrobial drugs, of which 173 prescriptions (24%) were prophylactic. A guideline was present for 95% of prescriptions, of which the guideline non-adherence rate was 25.6% (n = 42/164) for prophylaxis and 43.1% (n = 224/520) for therapy. Of all inappropriate prescriptions (n = 266), inappropriate prescriptions for skin and soft tissue infections (n = 60/226) and amoxicillin-clavulanic acid (n = 67/266) made up the largest proportion. In only 13 of 138 patients with impaired or unknown renal function the dosage regimen was adjusted. Amoxicillin-clavulanic acid was the drug for which most often renal function was not taken into account. In 94.6% of prescriptions the antibiotic plan was documented.

CONCLUSIONS

In hospital outpatient clinics, a substantial part of therapeutics were inappropriately prescribed. Amoxicillin-clavulanic acid was the most inappropriately prescribed drug, due to non-adherence to the guidelines and because dose adjustment to renal function was often not considered.

Antimicrobial utilization and antimicrobial resistance in patients with haematological malignancies in Japan: a multi-centre cross-sectional study

BACKGROUND

Infection is a major complication for patients with haematological malignancies. It is important to better understand the use of antimicrobial agents and antibiotic resistance for appropriate treatment and prevention of drug resistance. However, very few multi-centre analyses have focused on the use of antimicrobial agents and antibiotic resistance have been carried out in Japan. This study aimed to describe the characteristics of the use of antimicrobial agents and antibiotic resistance in patients with haematological malignancies.

METHODS

We conducted a cross-sectional study using administrative claims data and antimicrobial susceptibility data in Japan. We included patients diagnosed with haematological malignancies, who were hospitalized in a haematology ward between 1 April 2015 and 30 September 2017 in 37 hospitals. Descriptive statistics were used to summarize patient characteristics, antimicrobial utilization, bacterial infections, and antibiotic resistance.

RESULTS

In total, 8064 patients were included. Non-Hodgkin lymphoma (50.0%) was the most common malignancy. The broad-spectrum antibiotics displayed a following antimicrobial use density (AUD): cefepime (156.7), carbapenems (104.8), and piperacillin/tazobactam (28.4). In particular, patients with lymphoid leukaemia, myeloid leukaemia, or myelodysplastic syndromes presented a higher AUD than those with Hodgkin lymphoma, non-Hodgkin lymphoma, or multiple myeloma. The most frequent bacterial species in our study cohort was Escherichia coli (9.4%), and this trend was also observed in blood specimens. Fluoroquinolone-resistant E. coli (3.6%) was the most frequently observed antibiotic-resistant strain, while other antibiotic-resistant strains were rare.

CONCLUSIONS

Broad-spectrum antibiotics were common in patients with haematological malignancies in Japan; however, antibiotic-resistant bacteria including carbapenem-resistant or multidrug-resistant bacteria were infrequent. Our results provide nationwide, cross-sectional insight into the use of antimicrobial agents, prevalence of bacteria, and antibiotic resistance, demonstrating differences in antimicrobial utilization among different haematological diseases.

A genome-wide analysis of targets of macrolide antibiotics in mammalian cells

Macrolide antibiotics, such as erythromycin and josamycin, are natural polyketide products harboring 14- to 16-membered macrocyclic lactone rings to which various sugars are attached. These antibiotics are used extensively in the clinic because of their ability to inhibit bacterial protein synthesis. More recently, some macrolides have been shown to also possess anti-inflammatory and other therapeutic activities in mammalian cells. To better understand the targets and effects of this drug class in mammalian cells, we used a genome-wide shRNA screen in K562 cancer cells to identify genes that modulate cellular sensitivity to josamycin. Among the most sensitizing hits were proteins involved in mitochondrial translation and the mitochondrial unfolded protein response, glycolysis, and the mitogen-activated protein kinase signaling cascade. Further analysis revealed that cells treated with josamycin or other antibacterial agents exhibited impaired oxidative phosphorylation and metabolic shifts to glycolysis. Interestingly, we observed that knockdown of the mitogen-activated protein kinase kinase kinase 4 (MAP3K4) gene, which contributes to p38 mitogen-activated protein kinase signaling, sensitized cells only to josamycin but not to other antibacterial agents. There is a growing interest in better characterizing the therapeutic effects and toxicities of antibiotics in mammalian cells to guide new applications in both cellular and clinical studies. To our knowledge, this is the first report of an unbiased genome-wide screen to investigate the effects of a clinically used antibiotic on human cells.

Analysis of a high-prescribing state's 2016 outpatient antibiotic prescriptions: Implications for outpatient antimicrobial stewardship interventions

OBJECTIVE

To identify prescriber characteristics that predict antibiotic high-prescribing behavior to inform statewide antimicrobial stewardship interventions.

DESIGN

Retrospective analysis of 2016 IQVIA Xponent, formerly QuintilesIMS, outpatient retail pharmacy oral antibiotic prescriptions in Tennessee.

SETTING

Statewide retail pharmacies filling outpatient antibiotic prescriptions.

PARTICIPANTS

Prescribers who wrote at least 1 antibiotic prescription filled at a retail pharmacy in Tennessee in 2016.

METHODS

Multivariable logistic regression, including prescriber gender, birth decade, specialty, and practice location, and patient gender and age group, to determine the association with high prescribing.

RESULTS

In 2016, 7,949,816 outpatient oral antibiotic prescriptions were filled in Tennessee: 1,195 prescriptions per 1,000 total population. Moreover, 50% of Tennessee's outpatient oral antibiotic prescriptions were written by 9.3% of prescribers. Specific specialties and prescriber types were associated with high prescribing: urology (odds ratio [OR], 3.249; 95% confidence interval [CI], 3.208-3.289), nurse practitioners (OR, 2.675; 95% CI, 2.658-2.692), dermatologists (OR, 2.396; 95% CI, 2.365-2.428), physician assistants (OR, 2.382; 95% CI, 2.364-2.400), and pediatric physicians (OR, 2.340; 95% CI, 2.320-2.361). Prescribers born in the 1960s were most likely to be high prescribers (OR, 2.574; 95% CI, 2.532-2.618). Prescribers in rural areas were more likely than prescribers in all other practice locations to be high prescribers. High prescribers were more likely to prescribe broader-spectrum antibiotics (P < .001).

CONCLUSIONS

Targeting high prescribers, independent of specialty, degree, practice location, age, or gender, may be the best strategy for implementing cost-conscious, effective outpatient antimicrobial stewardship interventions. More information about high prescribers, such as patient volumes, clinical scope, and specific barriers to intervention, is needed.

Antibiotic Stewardship for Older Adults in Ambulatory Care Settings: Addressing an Unmet Challenge

Inappropriate antibiotic use is common in older adults (aged >65 y), and they are particularly vulnerable to serious antibiotic-associated adverse effects such as cardiac arrhythmias, delirium, aortic dissection, drug-drug interactions, and Clostridioides difficile. Antibiotic prescribing improvement efforts in older adults have been primarily focused on inpatient and long-term care settings. However, the ambulatory care setting is where the vast majority of antibiotic prescribing to older adults occurs. To help improve the clinical care of older adults, we review drivers of antibiotic prescribing in this population, explore systems aspects of ambulatory care that can create barriers to optimal antibiotic use, discuss existing stewardship interventions, and provide guidance on priority areas for future inquiry. J Am Geriatr Soc 68:244-249, 2020.

Use of oral third generation cephalosporins and quinolones and occurrence of antibiotic-resistant strains in the neurogenic bladder (NB) outpatient setting: a retrospective chart audit

STUDY DESIGN

A retrospective chart audit.

OBJECTIVES

Neurogenic bladder (NB), a risk factor for urinary tract infection, has not been comprehensively studied in terms of antimicrobial stewardship. In this study, we studied the relationship between the use of oral third generation cephalosporins and quinolones, and the occurrence of antibiotic-resistant strains.

SETTING

Hyogo Prefectural Central Rehabilitation Hospital, Hyogo, Japan.

METHODS

We retrospectively investigated antibiotic-resistant bacteria and the amount of antibiotics prescribed in outpatients with NB caused by spinal cord injury between 2012 and 2017. We intervened in urological departments whose physicians often prescribed third generation cephalosporins and fluoroquinolone, and analyzed the number of prescriptions and the amount of Cefdinir (CFDN) and Levofloxacin (LVFX), and studied changes of ratios in antibiotic-resistant strains such as extended-spectrum β-lactamases (ESBLs) and quinolone-resistant Escherichia coli and Klebsiella pneumoniae.

RESULTS

The number of CFDN prescriptions per year significantly decreased from 463 cases to 130 cases over 6 years (p = 0.012). The number of LVFX prescriptions per year decreased from 640 cases to 171 cases (p = 0.025). The incidence rate of ESBL-producing K. pneumoniae decreased from 25% to 7% of total K. pneumoniae (p < 0.001). The incidence of LVFX-resistant E. coli and K. pneumoniae significantly decreased in 2017 compared with 2012 (p = 0.03 and p = 0.016, respectively).

CONCLUSIONS

Antimicrobial stewardship interventions decreased the use of CFDN and LVFX for outpatients with NB. Our findings suggested that the reduction in the use of third generation cephalosporins and quinolones correlates with observed decrease in the occurrence of antibiotic-resistant, ESBL-producing, and quinolone-resistant bacteria.

Population-based assessment of patient and provider characteristics influencing pediatric outpatient antibiotic use in a high antibiotic-prescribing state

OBJECTIVE

To identify patient and provider characteristics associated with high-volume antibiotic prescribing for children in Tennessee, a state with high antibiotic utilization.

DESIGN

Cross-sectional, retrospective analysis of pediatric (aged <20 years) outpatient antibiotic prescriptions in Tennessee using the 2016 IQVIA Xponent (formerly QuintilesIMS) database.

METHODS

Patient and provider characteristics, including county of prescription fill, rural versus urban county classification, patient age group, provider type (nurse practitioner, physician assistant, physician, or dentist), physician specialty, and physician years of practice were analyzed.

RESULTS

Tennessee providers wrote 1,940,011 pediatric outpatient antibiotic prescriptions yielding an antibiotic prescribing rate of 1,165 per 1,000 population, 50% higher than the national pediatric antibiotic prescribing rate. Mean antibiotic prescribing rates varied greatly by county (range, 39-2,482 prescriptions per 1,000 population). Physicians wrote the greatest number of antibiotic prescriptions (1,043,030 prescriptions, 54%) of which 56% were written by general pediatricians. Pediatricians graduating from medical school prior to 2000 were significantly more likely than those graduating after 2000 to be high antibiotic prescribers. Overall, 360 providers (1.7% of the 21,798 total providers in this dataset) were responsible for nearly 25% of both overall and broad-spectrum antibiotic prescriptions; 20% of these providers practiced in a single county.

CONCLUSIONS

Fewer than 2% of providers account for 25% of pediatric antibiotic prescriptions. High antibiotic prescribing for children in Tennessee is associated with specific patient and provider characteristics that can be used to design stewardship interventions targeted to the highest prescribing providers in specific counties and specialties.

Risk Factors for Unnecessary Antibiotic Prescribing for Acute Respiratory Tract Infections in Primary Care

Objective

To determine independent risk factors for inappropriate antibiotic prescribing for acute respiratory tract infections (ARIs) in internal medicine (IM) residency–based primary care offices.

Patients and Methods

A retrospective study was conducted to measure antibiotic prescribing rates, and multivariable analysis was utilized to identify predictors of inappropriate prescribing among patients presenting to IM residency–based primary care office practices. Patients with an office visit at either of 2 IM residency–based primary care office practices from January 1, 2016, through December 31, 2016, with a primary encounter diagnosis of ARI were included.

Results

During the study period, 911 unique patient encounters were included with 518 for conditions for which antibiotics were considered always inappropriate. Antibiotics were not indicated in 85.8% (782 of 911) of encounters. However, antibiotics were prescribed in 28.4% (222 of 782) of these encounters. Inappropriate antibiotic prescribing occurred in 111 of 518 (21.4%) encounters for conditions for which antibiotics are always inappropriate. Using multivariable logistic regression analysis to assess for independent risk factors when adjusted for other potential risk factors for office visits at which antibiotics were not indicated, IM resident–associated visits (odds ratio, 0.25; 95% CI, 0.18-0.36) was the only variable independently associated with lower risk of inappropriate antibiotic prescribing.

Conclusion

For ARI visits at which antibiotics were not indicated, IM resident comanagement was associated with lower rates of inappropriate prescribing.