Association between antibiotic resistance and community prescribing: a critical review of bias and confounding in published studies

Estimating antibiotics consumption in a tertiary care hospital in Islamabad using a WHO's defined daily dose methodology

BACKGROUND

Antibiotics have helped to reduce the incidence of common infectious diseases in all modern healthcare systems, but improper use of antibiotics including their overuse and misuse can change the bacteria so much that antibiotics don't work against them. In case of developing imposable selective pressure with regard to the proportion of hospitalized patients who receive antibiotics, the quantity of antibiotics that are prescribed to them, and the proportion of patients who receive antibiotic treatment is one of the major contributors to the rising global health issue of antimicrobial resistance. Concerning the levels of antibiotic consumption in Pakistani hospitals, there is negligible research data available.

AIM

This study aimed to evaluate five-year inpatient antibiotic use in a tertiary care hospital in Islamabad using the World Health Organization (WHO) Recommended Anatomical Therapeutic Chemical (ATC) Classification / Defined Daily Dose (DDD) methodology.

METHOD

It was a descriptive study involving a retrospective record review of pharmacy records of antibiotics dispensed (amount in grams) to patients across different specialties of the hospital from January 2017 to December 2021 (i.e., 60 consecutive months). The antibiotic consumption was calculated by using the DDD/100-Bed Days (BDs) formula, and then relative percent change was estimated using Microsoft Excel 2021 edition.

RESULT

A total of 148,483 (77%) patients who received antibiotics were included in the study out of 193,436 patients admitted in the hospital. Antibiotic consumption trends showed considerable fluctuations over a five-year period. It kept on declining irregularly from 2017 to 2019, inclined vigorously in 2020, and then suddenly dropped to the lowest DDD/100 BDs value (96.02) in the last year of the study. The overall percentage of encounters in which antibiotics were prescribed at tertiary care hospital was 77% which is very high compared to the WHO standard reference value (< 30%). WATCH group antibiotics were prescribed (76%) and consumed more within inpatient settings than Access (12%) and Reserve (12%) antibiotics.

CONCLUSION

The hospital antibiotic consumption data is well maintained across different inpatient specialties but it is largely non-aligned with WHO AWaRe (Access-Watch-Reserve) antibiotics use and optimization during 2017-2021. Compared to the WHO standard reference figure, the overall percentage of antibiotics encountered was higher by about 47%. Antibiotic consumption trends vary with a slight increase in hospital occupancy rate, with positive relative changes being lower in number but higher in proportion than negative changes. Although the hospital antibiotics policy is in place but seems not to be followed with a high degree of adherence.

Determinants of Antimicrobial Resistance among the Different European Countries: More than Human and Animal Antimicrobial Consumption

Although antimicrobial consumption is considered the main driver of antimicrobial resistance (AMR), other factors probably have a significant but less studied impact. The study’s goal was to assess AMR drivers across different European countries and quantify their possible contributions using the latest data available. Using the ESAC-Net (European Surveillance of Antimicrobial Consumption Network) database, the ESVAC (European Surveillance of Veterinary Antimicrobial Consumption) database and the OECD (Organisation for Economic Cooperation and Development) information, a dataset including 23 European countries was created. Associations between AMR and potential contributing factors were assessed using bivariate correlation and multiple linear regression models for multivariable analyses. Factors associated with the AMR rate among European countries were human ambulatory consumption of antibiotics and per capita expenditure on health, meaning that the higher human ambulatory consumption of antibiotics and the lower the per capita expenditure on health, the higher the AMR. Both variables together explain 74% of AMR variation. Private expenditure on health in terms of % GDP (Gross Domestic Profit) was positively related to a higher AMR rate. In conclusion, considering antibiotic consumption as the most important factor contributing to AMR may be a deviant focus, as resistance transmission may be paramount for AMR levels. Low per capita expenditure on health, probably a surrogate of worse healthcare conditions and a high level of resistance transmission, has a strong correlation with the AMR rate. Increasing public expenditure on healthcare, to strengthen infection control structures and processes interventions, seems relevant to tackle antimicrobial resistance at the European scale.

Virulence Factors in Coagulase-Negative Staphylococci

Coagulase-negative staphylococci (CoNS) have emerged as major pathogens in healthcare-associated facilities, being S. epidermidis, S. haemolyticus and, more recently, S. lugdunensis, the most clinically relevant species. Despite being less virulent than the well-studied pathogen S. aureus, the number of CoNS strains sequenced is constantly increasing and, with that, the number of virulence factors identified in those strains. In this regard, biofilm formation is considered the most important. Besides virulence factors, the presence of several antibiotic-resistance genes identified in CoNS is worrisome and makes treatment very challenging. In this review, we analyzed the different aspects involved in CoNS virulence and their impact on health and food.

Genetic association of BIN1 and GAB2 in Alzheimer's disease: A meta-analysis and systematic review

Aim

Heredity plays an important role in the pathogenesis of Alzheimer's disease (AD) especially for single‐nucleotide polymorphism (SNPs) of susceptible genes, which is one of the significant factors in the pathogenesis of AD. The SNPs of BIN1 rs744373, BIN1 rs7561528 and GAB2 rs2373115 are associated with AD in Asian and white people.

Methods

We included 34 studies with a total of 38 291 patients with AD and 55 538 controls of diverse races from four main databases. We used meta‐analysis to obtain I²‐values and odds ratios of five genetic models in three SNPs. We carried out analysis of sensitivity, subgroup, publication bias and linkage disequilibrium test.

Results

The forest plots showed the odds ratio value of the three SNPs was >1 in white individuals, but not Asian individuals, in their genetic model. The funnel plot was symmetrical, and the D'‐value was 0.986 between rs744373 and rs7561528.

Conclusions

BIN1 rs744373, BIN1 rs7561528 and GAB2 rs2373115 are pathogenicity sites for AD in white people, and also rs7561528 belongs to a risk site in Asian people. The rs7561528 and rs744373 SNPs have strong linkage disequilibrium in Chinese people. In addition, apolipoprotein E ε4 status promotes them to result in the pathogenesis of AD. Geriatr Gerontol Int 2021; 21: 185–191.

Perinatal risk factors for fecal antibiotic resistance gene patterns in pregnant women and their infants

Perinatal factors can shape fecal microbiome patterns among pregnant women and their infants. However, there is scarce information about the effect of maternal demographics and perinatal exposures on antibiotic resistance genes (ARG) and mobile genetic element (MGE) patterns in pregnant women and infants. We examined fecal samples from pregnant women during their third trimester of pregnancy (n = 51) and 6-month-old infants (n = 40). Of the 91 participants, 72 represented 36 maternal-infant dyads, 15 were additional pregnant women, and 4 were additional infants. We assessed the effects of demographics, pre-pregnancy BMI, smoking and parity in the pregnancy resistome and the effects of demographics, delivery mode, feeding habits and prenatal antibiotic treatment on the infancy resistome. ARG and MGE richness and abundance were assessed using a SmartChip qPCR-array. Alpha diversity (Shannon and Inverse Simpson index) and beta diversity (Sorensen and Bray-Curtis index) were calculated. The Wilcoxon and the Kruskal non-parametric test were used for comparisons. There is a high variability in shared resistome patterns between pregnant women and their infants. An average of 29% of ARG and 24% of MGE were shared within dyads. Infants had significantly greater abundance and higher diversity of ARG and MGE compared to pregnant women. Pregnancy and infancy samples differed in ARG and MGE gene composition and structure. Composition of the fecal resistome was significantly associated with race in pregnant women, with non-white women having different patterns than white women, and, in infants, with extent of solid food consumption. Our data showed that the pregnancy and infancy resistome had different structure and composition patterns, with maternal race and infant solid food consumption as possible contributors to ARG. By characterizing resistome patterns, our results can inform the mechanism of antibiotic resistome development in pregnant women and their infants.

Modelling the effect of a dengue vaccine on reducing the evolution of resistance against antibiotic due to misuse in dengue cases

Background

This paper intends to check whether and how a hypothetical dengue vaccine could contribute to issue of evolution of bacteria resistance against antibiotics by reducing the number of patients that would inappropriately being treated with antibiotics.

Methods

We use a new mathematical model that combines, in a novel way, two previously published papers, one on the evolution of resistance against antibiotics and one classical Ross-Macdonald model for dengue transmission.

Results

The model is simulated numerically and reproduces a real case of evolution of resistance against antibiotics. In addition the model shows that the use of a hypothetical dengue vaccine could help to curb the evolution of resistance against an antibiotic inappropriately used in dengue patients. Both the increase in the proportion of resistant bacteria due to the misuse of antibiotics in dengue cases as a function of the fraction of treated patients and the reduction of that proportion as a function of vaccination coverage occur in a highly non-linear fashion.

Conclusion

The use of a dengue vaccine is helpful in reducing the rate of evolution of antibiotic resistance in a scenario of misuse of the antibiotics in dengue patients.

Impact of Chlorhexidine Bathing on Antimicrobial Utilization in Surgical Intensive Care Unit

BACKGROUND

This secondary analysis compared antimicrobial utilization among surgical intensive care unit patients randomized to every other day chlorhexidine bathing (chlorhexidine) versus daily soap and water bathing (soap-and-water) using data from the CHlorhexidine Gluconate BATHing trial.

MATERIALS AND METHODS

Antimicrobial utilization was quantified using defined daily dose (DDD)/100 patient-days and agent-days/100 patient-days for systemic antimicrobials. Antivirals (except oseltamivir), antiparasitics, and prophylaxis agents were excluded. The 2018 anatomic therapeutic chemical/DDD index was used to calculate DDD. Agent-days were calculated as the sum of calendar days where antimicrobials were administered. Patient-days were defined as time patients were at risk for health care-acquired infections plus up to 14 d. Primary analyses were conducted using linear regression adjusted for baseline Acute Physiology and Chronic Health Evaluation II scores.

RESULTS

Of 325 CHlorhexidine Gluconate BATHing trial patients, 312 (157 in soap-and-water and 155 in chlorhexidine) were included. The median (interquartile range) of total antimicrobial DDD/100 patient-days was 135.4 (75.2-231.8) for soap-and-water and 129.9 (49.2-215.3) for chlorhexidine. The median (interquartile range) of total antimicrobial agent-days/100 patient-days was 155.6 (83.3-243.2) for soap-and-water and 146.7 (66.7-217.4) for chlorhexidine. After adjusting for Acute Physiology and Chronic Health Evaluation II scores, chlorhexidine bathing was associated with a nonsignificant reduction in total antimicrobial DDD/100 patient-days (-3.9; 95% confidence interval, -33.9 to 26.1; P = 0.80) and total antimicrobial agent-days/100 patient-days (-10.3; 95% confidence interval, -34.7 to 14.1; P = 0.41).

CONCLUSIONS

Compared with daily soap and water bathing, every other day chlorhexidine bathing did not significantly reduce total antimicrobial utilization in surgical intensive care unit patients.

A Novel Antimicrobial-Phytochemical Conjugate With Antimicrobial Activity Against Streptococcus uberis, Enterococcus faecium, and Enterococcus faecalis

Antimicrobial resistance is one of the major threats to human and animal health. An effective strategy to reduce and/or delay antimicrobial resistance is to use combination therapies. Research in our laboratory has been focused on combination therapies of antimicrobials and phytochemicals and development of antimicrobial–phytochemical conjugates. In this study, we report the synthesis and antimicrobial activity of a novel sulfamethoxazole–gallic acid conjugate compound (Hybrid 1). Hybrid 1 not only showed much stronger activity than sulfamethoxazole towards Streptococcus uberis 19436, Enterococcus faecium 700221, and Enterococcus faecalis 29212, which were purchased from American Type Culture Collection (ATCC), but also exhibited a promising antimicrobial effect against two E. faecalis clinical isolates, one of which was multidrug-resistant. Further studies are warranted to establish the in vivo antimicrobial activity for Hybrid 1 and develop more potent sulfamethoxazole–gallic acid-based antimicrobial conjugates using hybrid 1 as a lead compound.

Bystander Selection for Antimicrobial Resistance: Implications for Patient Health

Antimicrobial therapy promotes resistance emergence in target infections and in off-target microbiota. Off-target resistance emergence threatens patient health when off-target populations are a source of future infections, as they are for many important drug-resistant pathogens. However, the health risks of antimicrobial exposure in off-target populations remain largely unquantified, making rational antibiotic stewardship challenging. Here, we discuss the contribution of bystander antimicrobial exposure to the resistance crisis, the implications for antimicrobial stewardship, and some novel opportunities to limit resistance evolution while treating target pathogens.

A Pilot Study to Investigate Antibiotic Prescribing in Private Dental Practice in the UK

This paper examines antibiotic prescribing by dental practitioners delivering private dental care in the UK. An online questionnaire utilising the online Surveymonkey tool was used to collate data on aspects of therapeutic and prophylactic antibiotic prescribing in private dental practice. In total, 53 private dental practitioners registered with Simplyhealth professionals (formerly DENPLAN Ltd) responded to this study. All respondents recognised that an elevated temperature associated with a dental infection requires a prescription of systemic antibiotics. Other reported indications for prescribing antibiotics, as an adjunct to definitive management of the cause, included gross diffuse swelling (50%), difficulty in swallowing (48%) or closure of the eye due to swelling (51%). The majority of respondents were found to prescribe the appropriate antibiotic at the correct dose, frequency and duration. Overall, private dental practitioners prescribed or dispensed fewer than six courses of antibiotics each month and just less than half the respondents did not audit their prescribing.<br/>The results of this limited pilot study suggest that most dental practitioners providing private dental care prescribe appropriately and at lower levels than NHS dental practitioners. A definitive larger study of private dental practitioners antibiotic prescribing would be of value in determining their contribution to reducing the development of antimicrobial resistance.

Patient-related factors, antibiotic prescribing and antimicrobial resistance of the commensal Staphylococcus aureus and Streptococcus pneumoniae in a healthy population - Hungarian results of the APRES study

Background

Antimicrobial resistance (AMR) is an increasing public health problem worldwide.

We studied some patient-related factors that might influence the antimicrobial resistance.

and whether the volume of antibiotic prescribing of the primary care physicians correlate with the antibiotic resistance rates of commensal nasal Staphylococcus aureus and Streptococcus pneumoniae.

Methods

The socio-demographic questionnaires, the antibiotic prescription and resistance data of commensal nasal S. aureus and S. pneumoniae were collected in the 20 participating Hungarian practices of the APRES study.

Multivariate logistic regression analyses were performed on the patient-related data and the antimicrobial resistance of the S. aureus and S. pneumoniae on individual, patient level.

Ecological analyses were performed with Spearman’s rank correlations at practice level, the analyses were performed in the whole sample (all practices) and in the cohorts of primary care practices taking care of adults (adult practices) or children (paediatric practices).

Results

According to the multivariate model, age of the patients significantly influenced the antimicrobial resistance of the S. aureus (OR = 0.42, p = 0.004) and S. pneumoniae (OR = 0.89, p < 0.001). Living with children significantly increased the AMR of the S. pneumoniae (OR = 1.23, p = 0.019). In the cohorts of adult or paediatric practices, neither the age nor other variables influenced the AMR of the S. aureus and S. pneumoniae.

At practice level, the prescribed volume of penicillins significantly correlated with the resistance rates of the S. aureus isolates to penicillin (rho = 0.57, p = 0.008). The volume of prescribed macrolides, lincosamides showed positive significant correlations with the S. pneumoniae resistance rates to clarithromycin and/or clindamycin in all practices (rho = 0.76, p = 0.001) and in the adult practices (rho = 0.63, p = 0.021).

Conclusions

The age is an important influencing factor of antimicrobial resistance. The results also suggest that there may be an association between the antibiotic prescribing of the primary care providers and the antibiotic resistance of the commensal S. aureus and S. pneumoniae. The role of the primary care physicians in the appropriate antibiotic prescribing is very important to avoid the antibiotic resistance.

Genotypic and phenotypic variations in methicillin-resistant Staphylococcus aureus isolates from outpatient, inpatient and nursing homes

PURPOSE

The epidemiological shift in MRSA distribution from healthcare-related facilities to the general population is distressing and requires continuous monitoring to manage and control the rate of incidences.

METHOD

The retrospective relationship between genetic and phenotypic variability of methicillin-resistant Staphylococcus aureus (MRSA) isolates was determined in respect to the specimen source, patient location, sex and age. A total of 521 MRSA isolates were classified based on SCCmec, mec, agr, pvl and spa genetic markers using three different multiplex PCRs.

RESULTS

Based on the genetic variability, the isolates were divided into 97 profiles, of which 59% belonged to only two profiles (P17 and P33). P17 was the predominate profile, harbouring SCCmecIVa, ccr2, mecB, agr1, spa413 and pvl markers. P17 was more prevalent among the younger population (average 33.9 years) from outpatient (77%) locations and wound (88%) sources. The second largest profile was P33, harbouring SCCmecII, ccr2+ccr3, mecA, agr2, spa413 and no PVL. P33 was more prevalent in the older population (average 70.7 years) and more common in females (62%) than males (38%). With respect to antibiotic resistance, P33 exhibited a high rate of resistance to penicillins, cephalosporins, fluoroquinolones and macrolides, and P17 had a lower resistance to fluoroquinolones.

CONCLUSION

This report contributes to the existing understanding of evolutionary epidemiology of antibiotic resistance in MRSA. The diversity of MRSA isolates and unique environmental preferences for each profile highlights the importance of epidemiological knowledge of MRSA distribution to determine the best treatment for patients in both community and hospital settings.

Global increase and geographic convergence in antibiotic consumption between 2000 and 2015

Tracking antibiotic consumption patterns over time and across countries could inform policies to optimize antibiotic prescribing and minimize antibiotic resistance, such as setting and enforcing per capita consumption targets or aiding investments in alternatives to antibiotics. In this study, we analyzed the trends and drivers of antibiotic consumption from 2000 to 2015 in 76 countries and projected total global antibiotic consumption through 2030. Between 2000 and 2015, antibiotic consumption, expressed in defined daily doses (DDD), increased 65% (21.1-34.8 billion DDDs), and the antibiotic consumption rate increased 39% (11.3-15.7 DDDs per 1,000 inhabitants per day). The increase was driven by low- and middle-income countries (LMICs), where rising consumption was correlated with gross domestic product per capita (GDPPC) growth (P = 0.004). In high-income countries (HICs), although overall consumption increased modestly, DDDs per 1,000 inhabitants per day fell 4%, and there was no correlation with GDPPC. Of particular concern was the rapid increase in the use of last-resort compounds, both in HICs and LMICs, such as glycylcyclines, oxazolidinones, carbapenems, and polymyxins. Projections of global antibiotic consumption in 2030, assuming no policy changes, were up to 200% higher than the 42 billion DDDs estimated in 2015. Although antibiotic consumption rates in most LMICs remain lower than in HICs despite higher bacterial disease burden, consumption in LMICs is rapidly converging to rates similar to HICs. Reducing global consumption is critical for reducing the threat of antibiotic resistance, but reduction efforts must balance access limitations in LMICs and take account of local and global resistance patterns.

Pediatric fluoroquinolone prescription in South Korea before and after a regulatory intervention: A nationwide study, 2007-2015

Objective

To investigate the impact of national implementation of age restriction on fluoroquinolone prescription in children and adolescents.

Methods

Data collected from the database of Health Insurance Review and Assessment Service in South Korea, a national health insurance system to analyze fluoroquinolone prescribing practice in children and adolescents younger than 18 years, between 2007 and 2015. The age restriction was implemented in December 2009. The annual prescription rate of FQ per 100,000 person-years was calculated and an autoregressive model was used to predict the prescription pattern if an intervention had not occurred.

Results

A total of 505,859 children received systemic fluoroquinolone during the study period—297,054 ciprofloxacin, and 208,805 levofloxacin. After implementation of the drug utilization review program, the annual prescription rate for ciprofloxacin declined by 97.5% (from 840 to 21 per 100,000 person-years, P < 0.001), and for levofloxacin by 96.4% (from 598 to 11 per 100,000 person-years, P < 0.001). The decline was more dramatic in the outpatient setting than in the inpatient setting for both drugs.

Conclusion

The dramatic and sustained decline in prescription number and change in prescription pattern after the regulatory action suggests that the implementation under drug utilization review program was successful in controlling excessive and inappropriate use of fluoroquinolones in children, possibly guiding towards more judicious and selective prescription behavior.

Impact of amoxicillin therapy on resistance selection in patients with community-acquired lower respiratory tract infections: a randomized, placebo-controlled study

OBJECTIVES

To determine the effect of amoxicillin treatment on resistance selection in patients with community-acquired lower respiratory tract infections in a randomized, placebo-controlled trial.

METHODS

Patients were prescribed amoxicillin 1 g, three times daily (n = 52) or placebo (n = 50) for 7 days. Oropharyngeal swabs obtained before, within 48 h post-treatment and at 28-35 days were assessed for proportions of amoxicillin-resistant (ARS; amoxicillin MIC ≥2 mg/L) and -non-susceptible (ANS; MIC ≥0.5 mg/L) streptococci. Alterations in amoxicillin MICs and in penicillin-binding-proteins were also investigated. ITT and PP analyses were conducted.

RESULTS

ARS and ANS proportions increased 11- and 2.5-fold, respectively, within 48 h post-amoxicillin treatment compared with placebo [ARS mean increase (MI) 9.46, 95% CI 5.57-13.35; ANS MI 39.87, 95% CI 30.96-48.78; P < 0.0001 for both]. However, these differences were no longer significant at days 28-35 (ARS MI -3.06, 95% CI -7.34 to 1.21; ANS MI 4.91, 95% CI -4.79 to 14.62; P > 0.1588). ARS/ANS were grouped by pbp mutations. Group 1 strains exhibited significantly lower amoxicillin resistance (mean MIC 2.8 mg/L, 95% CI 2.6-3.1) than group 2 (mean MIC 9.3 mg/L, 95% CI 8.1-10.5; P < 0.0001). Group 2 strains predominated immediately post-treatment (61.07%) and although decreased by days 28-35 (30.71%), proportions remained higher than baseline (18.70%; P = 0.0004).

CONCLUSIONS

By utilizing oropharyngeal streptococci as model organisms this study provides the first prospective, experimental evidence that resistance selection in patients receiving amoxicillin is modest and short-lived, probably due to 'fitness costs' engendered by high-level resistance-conferring mutations. This evidence further supports European guidelines that recommend amoxicillin when an antibiotic is indicated for community-acquired lower respiratory tract infections.

Predicting Antimicrobial Resistance Prevalence and Incidence from Indicators of Antimicrobial Use: What Is the Most Accurate Indicator for Surveillance in Intensive Care Units?

OBJECTIVE

The optimal way to measure antimicrobial use in hospital populations, as a complement to surveillance of resistance is still unclear. Using respiratory isolates and antimicrobial prescriptions of nine intensive care units (ICUs), this study aimed to identify the indicator of antimicrobial use that predicted prevalence and incidence rates of resistance with the best accuracy.

METHODS

Retrospective cohort study including all patients admitted to three neonatal (NICU), two pediatric (PICU) and four adult ICUs between April 2006 and March 2010. Ten different resistance/antimicrobial use combinations were studied. After adjustment for ICU type, indicators of antimicrobial use were successively tested in regression models, to predict resistance prevalence and incidence rates, per 4-week time period, per ICU. Binomial regression and Poisson regression were used to model prevalence and incidence rates, respectively. Multiplicative and additive models were tested, as well as no time lag and a one 4-week-period time lag. For each model, the mean absolute error (MAE) in prediction of resistance was computed. The most accurate indicator was compared to other indicators using t-tests.

RESULTS

Results for all indicators were equivalent, except for 1/20 scenarios studied. In this scenario, where prevalence of carbapenem-resistant Pseudomonas sp. was predicted with carbapenem use, recommended daily doses per 100 admissions were less accurate than courses per 100 patient-days (p = 0.0006).

CONCLUSIONS

A single best indicator to predict antimicrobial resistance might not exist. Feasibility considerations such as ease of computation or potential external comparisons could be decisive in the choice of an indicator for surveillance of healthcare antimicrobial use.

WITHDRAWN: Antibiotics for acute maxillary sinusitis in adults

Currently, two separate Cochrane reviews, ‘Antibiotics for acute maxillary sinusitis in adults ’ and ‘Antibiotics for clinically diagnosed acute rhinosinusitis in adults ’ describe the effect of antibiotics for acute rhinosinusitis. Although both Cochrane reviews study the same condition, they look at different populations (patients in which the diagnosis was based on clinical signs and symptoms and patients in which the diagnosis was confirmed by imaging). Because of this, the conclusions are different in these Cochrane reviews. This was confusing for clinicians who needed to read both Cochrane reviews to know which conclusions are most applicable to their patients.
 
 This review is being withdrawn and will be incorporated into the updated publication of ‘Antibiotics for clinically diagnosed acute rhinosinusitis in adults ’. This ‘merged’ review will still maintain the relevant distinction between the two populations. However, information on the effectiveness of antibiotics for rhinosinusitis will be published in the ‘merged’ Cochrane review. We will omit the comparison between antibiotics (as published in this Cochrane review) because the choice for certain antibiotics and/or doses differs according to the local antibiotic resistance patterns and therefore this comparison is less relevant.

The editorial group responsible for this previously published document have withdrawn it from publication.

Risk and Prognostic Factors for Multidrug-Resistant Acinetobacter Baumannii Complex Bacteremia: A Retrospective Study in a Tertiary Hospital of West China

Background

The increasing prevalence and mortality of multidrug-resistant (MDR) Acinetobacter baumannii complex-associated infections, especially bacteremia, in health care settings poses a great threat to public health. We proceeded to investigate the risk and prognostic factors for MDR A. baumannii complex bacteremia in mainland China.

Methods

This retrospective study was conducted at West China Hospital from January 2009 to December 2013. Using a computer-assisted microbiology laboratory database, patients with MDR A. baumannii complex bacteremia were included as the case group, while those infected with non-MDR A. baumannii complex were selected as the control group. The clinical data were collected and analyzed.

Results

There were 241 non-duplicated A. baumannii complex blood isolates identified in our research, with the overall rate of multidrug resistance reaching 75.52% over the past five years. Using multivariate logistic analysis, being in the intensive care unit (ICU) (adjusted odds ratio [aOR], 5.84; 95% confidence interval [CI], 1.67-20.44), increased Pittsburgh bacteremia score (aOR, 6.55; 95% CI, 1.27-33.70) and use of carbapenem (aOR, 8.90; 95% CI, 1.71-46.30) were independent risk factors for MDR acquisition among patients with A. baumannii complex bacteremia. Older age (aOR, 1.02; 95% CI, 1.00-1.04), being post-transplantation (aOR, 5.21; 95% CI, 1.13-24.04), having a higher Pittsburgh bacteremia score (aOR, 2.19; 95% CI, 1.08-4.47) and having a lower level of albumin (aOR, 0.93; 95% CI, 0.88-0.99) were identified as independent risk factors for 30-day mortality in patients with MDR A. baumannii complex bacteremia.

Conclusion

In conclusion, our research revealed the risk factors associated with acquisition of and mortality from MDR A. baumannii complex bacteremia, which may be used to prioritize infection control practices and prognostic evaluations.

Clinical practice guideline (update): adult sinusitis

OBJECTIVE

This update of a 2007 guideline from the American Academy of Otolaryngology--Head and Neck Surgery Foundation provides evidence-based recommendations to manage adult rhinosinusitis, defined as symptomatic inflammation of the paranasal sinuses and nasal cavity. Changes from the prior guideline include a consumer added to the update group, evidence from 42 new systematic reviews, enhanced information on patient education and counseling, a new algorithm to clarify action statement relationships, expanded opportunities for watchful waiting (without antibiotic therapy) as initial therapy of acute bacterial rhinosinusitis (ABRS), and 3 new recommendations for managing chronic rhinosinusitis (CRS).

PURPOSE

The purpose of this multidisciplinary guideline is to identify quality improvement opportunities in managing adult rhinosinusitis and to create explicit and actionable recommendations to implement these opportunities in clinical practice. Specifically, the goals are to improve diagnostic accuracy for adult rhinosinusitis, promote appropriate use of ancillary tests to confirm diagnosis and guide management, and promote judicious use of systemic and topical therapy, which includes radiography, nasal endoscopy, computed tomography, and testing for allergy and immune function. Emphasis was also placed on identifying multiple chronic conditions that would modify management of rhinosinusitis, including asthma, cystic fibrosis, immunocompromised state, and ciliary dyskinesia.

ACTION STATEMENTS

The update group made strong recommendations that clinicians (1) should distinguish presumed ABRS from acute rhinosinusitis (ARS) caused by viral upper respiratory infections and noninfectious conditions and (2) should confirm a clinical diagnosis of CRS with objective documentation of sinonasal inflammation, which may be accomplished using anterior rhinoscopy, nasal endoscopy, or computed tomography. The update group made recommendations that clinicians (1) should either offer watchful waiting (without antibiotics) or prescribe initial antibiotic therapy for adults with uncomplicated ABRS; (2) should prescribe amoxicillin with or without clavulanate as first-line therapy for 5 to 10 days (if a decision is made to treat ABRS with an antibiotic); (3) should reassess the patient to confirm ABRS, exclude other causes of illness, and detect complications if the patient worsens or fails to improve with the initial management option by 7 days after diagnosis or worsens during the initial management; (4) should distinguish CRS and recurrent ARS from isolated episodes of ABRS and other causes of sinonasal symptoms; (5) should assess the patient with CRS or recurrent ARS for multiple chronic conditions that would modify management, such as asthma, cystic fibrosis, immunocompromised state, and ciliary dyskinesia; (6) should confirm the presence or absence of nasal polyps in a patient with CRS; and (7) should recommend saline nasal irrigation, topical intranasal corticosteroids, or both for symptom relief of CRS. The update group stated as options that clinicians may (1) recommend analgesics, topical intranasal steroids, and/or nasal saline irrigation for symptomatic relief of viral rhinosinusitis; (2) recommend analgesics, topical intranasal steroids, and/or nasal saline irrigation) for symptomatic relief of ABRS; and (3) obtain testing for allergy and immune function in evaluating a patient with CRS or recurrent ARS. The update group made recommendations that clinicians (1) should not obtain radiographic imaging for patients who meet diagnostic criteria for ARS, unless a complication or alternative diagnosis is suspected, and (2) should not prescribe topical or systemic antifungal therapy for patients with CRS.

Patterns of antibacterial use and impact of age, race/ethnicity, and geographic region on antibacterial use in an outpatient medicaid cohort

STUDY OBJECTIVES

To describe patterns of outpatient antibacterial use among California Medicaid (Medi-Cal) fee-for-service system beneficiaries, and to investigate the influence of demographic factors-age, race/ethnicity, state county, and population density-on those patterns.

DESIGN

Retrospective analysis of administrative claims data.

DATA SOURCE

Medi-Cal fee-for-service system claims database.

PATIENTS

All outpatient Medi-Cal fee-for-service system beneficiaries enrolled between 2006 and 2011 who had at least one systemic antibacterial claim.

MEASUREMENTS AND MAIN RESULTS

Rates of antibacterial prescribing and the proportion of broad-spectrum antibacterial use were measured over the study period and among age, racial/ethnic, and geographic (county) groups. Of the 10,018,066 systemic antibacterial claims selected for analysis, antibacterial prescribing rates decreased from 542 claims/1000 beneficiaries in 2006 to 461 claims/1000 beneficiaries in 2011 (r = -0.971, p=0.0012; τ-b = -1.00, p=0.009). Among age groups, children had the highest rate of use (605 claims/1000 beneficiaries, χ(2) (2) = 320,000, p<0.001); among racial/ethnic groups, Alaskan Natives and Native Americans had the highest rate of use (1086/1000 beneficiaries, χ(2) (5) = 197,000, p<0.001). Broad-spectrum antibacterial prescribing increased from 28.1% (95% confidence interval [CI] 28.1-28.2%) to 32.7% (95% CI 32.6-32.8%) over the study period. Senior age groups and whites received the highest proportions of broad-spectrum agents (53.4% [95% CI 52.5-54.3%] and 36.6% [95% CI 36.6-36.7%], respectively). Population density was inversely related to both overall antibacterial use (ρ = -0.432, p=0.0018) and broad-spectrum antibacterial prescribing (ρ = -0.359, p<0.001). The rate of prescribing decreased over the study period for all antibacterial classes with the exception of macrolides and sulfonamides. Amoxicillin was the most frequently prescribed agent.

CONCLUSION

Overall and broad-spectrum antibacterial use in the Medi-Cal fee-for-service program are less than that observed nationally. Significant variations in prescribing exist between age and racial/ethnic groups, and heavily populated areas are associated with both less antibacterial use and less broad-spectrum antibacterial prescribing. Studies are needed to determine the reasons for the observed differences in antibacterial use among demographic groups.

Antibiotics for acute maxillary sinusitis in adults

BACKGROUND

Sinusitis is one of the most common diagnoses among adults in ambulatory care, accounting for 15% to 21% of all adult outpatient antibiotic prescriptions. However, the role of antibiotics for sinusitis is controversial.

OBJECTIVES

To assess the effects of antibiotics in adults with acute maxillary sinusitis by comparing antibiotics with placebo, antibiotics from different classes and the side effects of different treatments.

SEARCH METHODS

We searched CENTRAL 2013, Issue 2, MEDLINE (1946 to March week 3, 2013), EMBASE (1974 to March 2013), SIGLE (OpenSIGLE, later OpenGrey (accessed 15 January 2013)), reference lists of the identified trials and systematic reviews of placebo-controlled studies. We also searched for ongoing trials via ClinicalTrials.gov and the WHO International Clinical Trials Registry Platform (ICTRP). We imposed no language or publication restrictions.

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing antibiotics with placebo or antibiotics from different classes for acute maxillary sinusitis in adults. We included trials with clinically diagnosed acute sinusitis, confirmed or not by imaging or bacterial culture.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened search results, extracted data and assessed trial quality. We calculated risk ratios (RRs) for differences between intervention and control groups in whether the treatment failed or not. All measures are presented with 95% confidence intervals (CIs). We conducted the meta-analyses using either the fixed-effect or random-effects model. In meta-analyses of the placebo-controlled studies, we combined data across antibiotic classes. Primary outcomes were clinical failure rates at 7 to 15 days and 16 to 60 days follow-up. We used GRADEpro to assess the quality of the evidence.

MAIN RESULTS

We included 63 studies in this updated review; nine placebo-controlled studies involving 1915 participants (seven of the studies clearly conducted in primary care settings) and 54 studies comparing different classes of antibiotics (10 different comparisons). Five studies at low risk of bias comparing penicillin or amoxicillin to placebo provided information on the main outcome: clinical failure rate at 7 to 15 days follow-up, defined as a lack of full recovery or improvement, for participants with symptoms lasting at least seven days. In these studies antibiotics decreased the risk of clinical failure (pooled RR of 0.66, 95% CI 0.47 to 0.94, 1084 participants randomised, 1058 evaluated, moderate quality evidence). However, the clinical benefit was small. Cure or improvement rates were high in both the placebo group (86%) and the antibiotic group (91%) in these five studies. When clinical failure was defined as a lack of full recovery (n = five studies), results were similar: antibiotics decreased the risk of failure (pooled RR of 0.73, 95% CI 0.63 to 0.85, high quality evidence) at 7 to 15 days follow-up.Adverse effects in seven of the nine placebo-controlled studies (comparing penicillin, amoxicillin, azithromycin or moxicillin to placebo) were more common in antibiotic than in placebo groups (median of difference between groups 10.5%, range 2% to 23%). However, drop-outs due to adverse effects were rare in both groups: 1.5% in antibiotic groups and 1% in control groups.In the 10 head-to-head comparisons, none of the antibiotic preparations were superior to another. However, amoxicillin-clavulanate had significantly more drop-outs due to adverse effects than cephalosporins and macrolides.

AUTHORS' CONCLUSIONS

There is moderate evidence that antibiotics provide a small benefit for clinical outcomes in immunocompetent primary care patients with uncomplicated acute sinusitis. However, about 80% of participants treated without antibiotics improved within two weeks. Clinicians need to weigh the small benefits of antibiotic treatment against the potential for adverse effects at both the individual and general population levels.

Antibiotic and bronchodilator prescribing for acute bronchitis in the emergency department

BACKGROUND

Although the overuse of antibiotics and underuse of bronchodilators for treatment of acute bronchitis is well known, few studies have analyzed these trends in the emergency department (ED).

STUDY OBJECTIVES

To characterize the antibiotic and bronchodilator prescribing practices of physicians at two academic EDs in the diagnosis of acute bronchitis, and to identify factors that may or may not be associated with these practices.

METHODS

A computer database was searched retrospectively for all patients with an ED discharge diagnosis of acute bronchitis, and analyzed, looking at the frequency of antibiotic prescriptions, the class of antibiotic prescribed, and several other related factors including age, gender, chief complaint, duration of cough, and comorbid conditions.

RESULTS

During the study period, there were 836 cases of acute bronchitis in adults. Of these, 622 (74.0%) were prescribed antibiotics. Of those prescribed antibiotics, 480 (77.2%) were prescribed broad-spectrum antibiotics. Using multivariate analysis (odds ratio, 95% confidence interval), antibiotics were prescribed significantly more often in patients aged 50 years or older (1.7, 1.2-2.5) and in smokers (1.5, 1.0-2.2). Of patients without asthma, 346 (49.9%) were discharged without a bronchodilator, and 631 (91.1%) were discharged without a spacer device.

CONCLUSION

Antibiotics are over-prescribed in the ED for acute bronchitis, with broad-spectrum antibiotics making up the majority of the antibiotics prescribed. Age ≥50 years and smoking are associated with higher antibiotic prescribing rates.

Knowledge, attitudes and behavior regarding antibiotics use and misuse among adults in the community of Jordan. A pilot study

Factors associated with antibiotic use, resistance and safety have been well recognized worldwide in the literature. Nevertheless, only few studies have been conducted in Jordan in this area. The aim of this study was to assess knowledge, behavior and attitude toward antibiotics use among adult Jordanians. The study represents a cross sectional survey using an interviewer administered questionnaire. Data collected from a random sample of 1141 adult Jordanians, recruited at different settings, regarding their knowledge about the effectiveness of, resistance toward, and self medications with antibiotics against bacterial, viral and parasitic diseases. 67.1% believed that antibiotics treat common cold and cough. 28.1% misused antibiotics as analgesics. 11.9% of females showed inadequate knowledge about the safe use of antibiotics during pregnancy and nursing. 28.5% kept antibiotics at home for emergency use and 55.6% use them as prophylaxis against infections. 49.0% use left-over antibiotics without physicians' consultation while 51.8% use antibiotics based on a relative advice. 22.9% of physicians prescribe antibiotics over the phone and >50.0% routinely prescribe antibiotics to treat common cold symptoms. Our findings indicated that young adults showed unsatisfactory knowledge of proper antibiotic use. Therefore, there is an urge for educational programs using all media means.

Mortality following nursing home-acquired lower respiratory infection: LRI severity, antibiotic treatment, and water intake

OBJECTIVE

In some nursing home populations, antibiotic treatment may not reduce mortality following lower respiratory infection (LRI). To better inform treatment decisions, we determined influences on mortality following LRI among antibiotic-treated and non-antibiotic-treated residents in 2 populations.

DESIGN

Observational, prospective, cohort studies.

SETTING

Ninety-seven nursing homes (36 US, 61 Netherlands).

PARTICIPANTS

Residents (1044 US, 513 Netherlands) who met a standardized study definition for LRI.

MEASUREMENTS

Demographics, symptoms and physical findings of LRI, functional status, major illness diagnoses, dementia status, treatments, and date of death within 6 months after diagnosis.

METHODS

We estimated a 2-period (0-14/15-90 days) weighted proportional hazards model of mortality for antibiotic-treated (n = 1280) and non-antibiotic-treated (n = 277) residents; both weights and regressors provide "doubly robust" risk adjustment-for LRI (illness) severity using a prognostic score and for nonrandom receipt of antibiotic treatment using a propensity score.

RESULTS

In both the United States and the Netherlands, 14-day mortality was associated with three factors-LRI severity, water intake at diagnosis, and antibiotic use (not directly by severe dementia)-that accounted for 82% or, sequentially, 39%, 42%, and 1% of the cross-national mortality difference. The LRI Severity Score (based only on at-diagnosis eating dependency, pulse rate, decreased alertness, and breathing difficulty, with adequate discrimination [c ≥ 0.74] and calibration, and cross-indexed to commonly used LRI mortality measures) was related to mortality through 90 days, regardless of treatment. With sufficient water intake at diagnosis, 14-day mortality was unrelated to not receiving antibiotic treatment (adjusted hazard ratio [AHR], 1.20; 95% confidence interval, 0.70-2.04); insufficient water intake was related to increased 14-day mortality with antibiotics (AHR, 1.90; 1.38-2.60) or without (AHR, 7.12; 4.83-10.5). After 14 days, relative mortality worsened for antibiotic-treated residents with insufficient water intake. Inadequate water intake was related to increased eating dependence at onset of the LRI (OR, 4.2; 3.0-5.8).

CONCLUSION

LRI severity, water intake, and antibiotic use explain mortality in both studies and reconcile cross-study Dutch/US 14-day mortality differences. LRI severity, derived at 14 days, is related to mortality through 90 days, regardless of treatment, and is key to risk adjustment. With adequate hydration, the survival benefit from antibiotic use is nonsignificant. Conversely, hydration, even without antibiotic treatment, appears central to curative treatment. In LRI guidelines, treatment, and research, the relative benefits of antibiotics and hydration for curative treatment should be addressed.

Antimicrobial drug use and resistance in Europe

Routine surveillance data indicate a relation between use and resistance and support interventions designed to reduce antimicrobial consumption at a national level in Europe.

Our study confronts the use of antimicrobial agents in ambulatory care with the resistance trends of 2 major pathogens, Streptococcus pneumoniae and Escherichia coli, in 21 European countries in 2000–2005 and explores whether the notion that antimicrobial drug use determines resistance can be supported by surveillance data at national aggregation levels. The data obtained from the European Surveillance of Antimicrobial Consumption and the European Antimicrobial Resistance Surveillance System suggest that variation of consumption coincides with the occurrence of resistance at the country level. Linear regression analysis showed that the association between antimicrobial drug use and resistance was specific and robust for 2 of 3 compound pathogen combinations, stable over time, but not sensitive enough to explain all of the observed variations. Ecologic studies based on routine surveillance data indicate a relation between use and resistance and support interventions designed to reduce antimicrobial drug consumption at a national level in Europe.

Developing an 'interactive' booklet on respiratory tract infections in children for use in primary care consultations

OBJECTIVE

To construct a systematic process for developing an 'interactive' booklet for use in primary care consultations and to use this process to develop a booklet on respiratory tract infections in children.

METHODS

Booklet development occurred through a number of stages, which included: expert group brainstorming and literature review, professional graphic design, readability assessment, and consultation with users. Consultation was achieved through the use of focus groups and interviews with parents, focus groups and independent booklet review by general practitioners, and booklet review and feedback by paediatricians.

RESULTS

All development stages led to meaningful enhancements to the booklet. Consultation with parents demonstrated a desire for more information than anticipated, with a particular emphasis on the interpretation of signs and symptoms, and the recognition of serious illness. General practitioners contributed to the design and clarity of the booklet and helped to ensure that it would be acceptable for use within consultations.

CONCLUSION

Written material needs to be developed in a systematic way and include consultation with the intended users. Focus groups are a valuable tool for consulting with consumers and practitioners in this regard.

PRACTICE IMPLICATIONS

The process described can be used as a guide for those wishing to develop similar written materials.

Antibiotics for acute maxillary sinusitis

BACKGROUND

Expert opinions vary on the appropriate role of antibiotics for sinusitis, one of the most commonly diagnosed conditions among adults in ambulatory care.

OBJECTIVES

We examined whether antibiotics are effective in treating acute sinusitis, and if so, which antibiotic classes are the most effective.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, 2007, Issue 3); MEDLINE (1950 to May 2007) and EMBASE (1974 to June 2007).

SELECTION CRITERIA

Randomized controlled trials (RCTs) comparing antibiotics with placebo or antibiotics from different classes for acute maxillary sinusitis in adults. We included trials with clinically diagnosed acute sinusitis, whether or not confirmed by radiography or bacterial culture.

DATA COLLECTION AND ANALYSIS

At least two review authors independently screened search results, extracted data and quality assessed trials. Risk ratios (RR) were calculated for differences in the intervention and control groups to see whether or not the treatment was a failure. In meta-analysing the placebo-controlled studies, the data across antibiotic classes were combined. Primary outcomes were the clinical failure rates at 7 to 15 days and 16 to 60 days follow up.

MAIN RESULTS

Fifty-seven studies were included in the review; six placebo-controlled studies and 51 studies comparing different classes of antibiotics. Five studies involving 631 participants provided data for comparison of antibiotics to placebo, when clinical failure was defined as a lack of cure or improvement at 7 to 15 days follow up. These studies found a slight statistical difference in favor of antibiotics, compared to placebo, with a pooled RR of 0.66 (95% confidence interval (CI) 0.44 to 0.98). However, the clinical significance of the result is equivocal, also considering that cure or improvement rate was high in both the placebo group (80%) and the antibiotic group (90%). Based on six studies, when clinical failure was defined as a lack of total cure, there was significant difference in favor of antibiotics compared to placebo with a pooled RR of 0.74 (95% CI 0.65 to 0.84) at 7 to 15 days follow up. None of the antibiotic preparations was superior to each other.

AUTHORS' CONCLUSIONS

Antibiotics have a small treatment effect in patients with uncomplicated acute sinusitis in a primary care setting with symptoms for more than seven days. However, 80% of participants treated without antibiotics improve within two weeks. Clinicians need to weigh the small benefits of antibiotic treatment against the potential for adverse effects at both the individual and general population level.

Prior antibiotics and risk of antibiotic-resistant community-acquired urinary tract infection: a case–control study

BACKGROUND

To assess the effect of previous antibiotic use on the risk of a resistant Escherichia coli urinary tract infection (UTI), we undertook a case-control study with prospective measurement of outcomes in 10 general practices in the UK.

METHODS

Urinary samples from all patients with symptoms suggestive of UTIs were sought, and those with a laboratory-proven E. coli infection were interviewed and their medical records examined. Case patients were those with ampicillin- or trimethoprim-resistant infections and control patients had infections that were susceptible to antibiotics, including ampicillin and trimethoprim.

RESULTS

Risk of ampicillin-resistant E. coli infection in 903 patients was associated with amoxicillin prescriptions of >or=7 days duration in the previous 1 month [odds ratio (OR)=3.91, 95% CI 1.64-9.34] and previous 2-3 months (2.29, 1.12-4.70) before illness onset. For prescriptions <7 days duration, there was no statistically significant association. Higher doses of amoxicillin were associated with lower risk of ampicillin resistance. For trimethoprim-resistant E. coli infections, the OR was 8.44 (3.12-22.86) for prescriptions of trimethoprim of >or=7 days in the previous month and 13.91 (3.32-58.31) for the previous 2-3 months. For trimethoprim prescriptions of <7 days, the OR was 4.03 (1.69-9.59) for the previous month but prescribing in earlier periods was not significantly associated with resistance.

CONCLUSIONS

Within the community setting, exposure to antibiotics is a strong risk factor for a resistant E. coli UTI. High-dose, shorter-duration antibiotic regimens may reduce the pressure on the emergence of antibiotic resistance.

Problems of basing patient recruitment for primary care studies on routine laboratory submissions

BACKGROUND

Use of routine urine submission rates for estimation of patient enrollment in primary care studies of acute urinary symptoms may overestimate patient recruitment rate.

AIMS

To compare the rates of submission of urines and significant bacteriuria from patients presenting with acute urinary symptoms in study general practices to routine microbiology laboratory urines.

METHODS

Routine laboratory urine submissions were determined by counting all mid-stream urine specimens submitted to the laboratory from 12 large general practitioner (GP) practices served by Gloucester and Southmead microbiology departments over two years (2000-02). Urine specimens were requested from all patients with acute urinary symptoms referred at research nurse practice visits over the same time period. The annual study urine submission was calculated using the ratio of the number of nurse practice visits to the annual number of possible consulting sessions. Significant bacteriuria was defined as a urine growing a single organism reported as >10(5) colony forming units/ml. Rates per 1000 patients were calculated using practice population data.

RESULTS

The urine submission rate from study patients with acute urinary symptoms was one-third the routine urine submission rate from the same practices. The significant bacteriuria rate attained from the study was less than half the routine significant bacteriuria rate.

CONCLUSION

Two-thirds of routine urine samples submitted by GPs are probably not for the investigation of acute urinary symptoms. Basing consultation sample size power calculations for primary care studies or sentinel practice-based surveillance in urinary tract infection on routine laboratory submissions is unreliable and will lead to significant overestimation of recruitment rate.

Antimicrobial drugs in the home, United Kingdom

Persons more knowledgeable about these drugs are more likely to keep them.

A total of 6% of 6,983 households in the United Kingdom had leftover antimicrobial drugs, and 4% had standby antimicrobial drugs. Respondents with leftover drugs were more educated, more knowledgeable about antimicrobial drugs, younger, and female. Of respondents with leftover drugs, 44% kept them in case of future need, and 18% had taken these drugs without medical advice.

The 2005 Garrod Lecture: the changing access of patients to antibiotics--for better or worse?

Expanding the range of health professionals who can supply prescription medicines has been a policy of the UK National Health Service (NHS) since 2000, the most recent change being the establishment of nurse and pharmacist independent prescribers. In addition, patients now have a wider choice of how they access treatment for infections, particularly through the availability of antibiotics through community pharmacists under Patient Group Directions and Supplementary Prescribing. There is also a drive to reclassify medicines where possible from Prescription Only to Pharmacy Medicines. Patients can easily obtain antibiotics via the Internet, now available in more than half of UK households, and from their own and others' leftovers of prescribed courses. The first of these has considerable hazards for individual patients. The benefits to patients of the regulatory changes are largely ease of access to treatment for relatively minor illnesses, and their increased awareness and self-reliance that comes from this. More informed self-care should encourage the better use of healthcare resources. There could also be financial savings for the NHS if more patients purchased their medicines. Information on whether the changes in access have led to increased usage is scanty, since information on some of the supply is not collected. No doubt some of the usage from non-medical sources will be substitution, although there may well be an increase overall. It is possible that supply by non-medical professionals could lead to a closer adherence to protocols for the use of antibiotics. Whether the changes in access will have an impact on the prevalence of antimicrobial resistance is even harder to determine, especially as there is still much uncertainty about which parameters of antibiotic consumption encourage resistance. Within the context of the widespread use of antibiotics from extra-regulatory sources, it is hard to see how a modest increase in usage resulting from the changes in the regulations would have a significant impact on resistance. One issue to emerge from these changes is the mixed message given by official sources on antibiotic usage, with on the one hand placing an emphasis on containing resistance (and hence restricting antibiotic use) and on the other widening access and encouraging the reclassification of antimicrobials.

Antibacterial Use andStreptococcus pneumoniaePenicillin Resistance: A Temporal Relationship Model

The nature of the temporal relationship between antibacterial consumption and Streptococcus pneumoniae penicillin resistance is investigated using population level data across time. IMS Health Global Services provided national outpatient antibiotic prescription data for the years 1996-2003 from France, Spain, Italy, Germany, the United Kingdom, and the United States. Surveillance data consist of S. pneumoniae isolates obtained from a surveillance database in the same geographic regions from 1996 to 2003. A linear mixed model for repeated measures was used to analyze the association between resistance and several antibacterial classes through time. Changes in penicillin resistance through time in any country are better explained by the weighted cumulative antibacterial consumption with a 2-year lag. Narrow-spectrum penicillins are associated with lower resistance rates. Large reductions in consumption at the population level are needed to affect resistance. There is a peak level of penicillin resistance associated with cumulative exposure to a combination of antibiotic classes that is unique for every country.

The Antimicrobial Treatment Strategies (MIKSTRA) Program: A 5-Year Follow-Up of Infection-Specific Antibiotic Use in Primary Health Care and the Effect of Implementation of Treatment Guidelines

BACKGROUND

A national 5-year follow-up study of infection-specific antibiotic use in primary care was conducted to see if prescribing practices change after implementing new treatment guidelines.

METHODS

The data were collected during 1 week of November each year from 1998 to 2002 from 30 health care centers that covered a total population of 819,777 persons and in 2002 from 20 control health care centers that covered a population of 545,098 persons. National guidelines for 6 major infections (otitis media, sinusitis, throat infection, acute bronchitis, urinary tract infection, and bacterial skin infection) were published in 1999-2000. Multifaceted interventions were performed by local trainers teaching his or her coworkers, supported by feedback and patient and public information.

RESULTS

The 6 infections targeted for intervention, together with unspecified upper respiratory tract infection constituted 80%-85% of all infections. The proportion of patients who received prescriptions for antibiotics did not change significantly. However, use of first-line antibiotics increased for all infections, and the change was significant for sinusitis (P<.001), acute bronchitis (P=.015), and urinary tract infections (P=.009). Also, the percentage of antibiotic treatments prescribed for the recommended duration increased significantly. Correct prescribing for respiratory tract infections improved by 6.4 percentage units (P<.001). However, there was no statistically significant difference in performance between study and control health care centers at follow-up.

CONCLUSIONS

Moderate qualitative improvements in antibiotic use were observed after multifaceted intervention, but prescribing for unjustified indications, mainly acute bronchitis, did not decrease. Obtained infection-specific information on management of patients with infections in primary health care is an important basis for planning targeted interventions in the future.

Community consumption of antibacterial drugs within the Jordanian population: sources, patterns and appropriateness

This study is the first of its type to evaluate sources, patterns and appropriateness of antibacterial drug consumption within the Jordanian population. It uses a structured random interview to customers arriving at community pharmacy stores seeking antibacterial medication for systemic infections. Dispensed antibacterial drugs belonged to eight different main classes of systemically used antibacterial drugs in accordance with the Anatomical Therapeutic Chemical (ATC) classification system. Just less than one-half of all dispensed antibacterial drugs were without a prescription (46%), either via self-medication (23.2%) or pharmacist recommendation (23.1%). Inappropriateness in use was seen in 29.9% and 34% of the prescribed and non-prescribed (over-the-counter) antibacterial drugs, respectively. No uniformity in the treatment profile of the different treated complaints was seen. Our study shows great misuse and abuse of antibacterial drugs and hence there is a need to force regulations to control community use of antibacterial drugs and to increase awareness of the consequences of their inappropriate and uncontrolled use.

Use of avilamycin for growth promotion and avilamycin-resistance among Enterococcus faecium from broilers in a matched case–control study in France

We assessed the putative link between avilamycin-resistant Enterococcus faecium carriage and avilamycin consumption in broilers. As part of the French programme of monitoring for antimicrobial resistance, broilers sampled at slaughterhouse in 1999 and 2000 and carrying avilamycin-resistant E. faecium were matched by slaughterhouse, slaughter month and production type (free-range, standard, light) with control broilers carrying avilamycin-susceptible strains. History of antibiotics consumption (either for growth promotion or therapeutic purpose) in the broiler flocks sampled was collected from the monitoring programme and consumption of each antibiotic class was screened as a potential risk factor. Avilamycin was a risk factor for avilamycin-resistant E. faecium carriage: OR=2.3.

The relationship between primary care antibiotic prescribing and bacterial resistance in adults in the community: a controlled observational study using individual patient data

OBJECTIVES

To examine the relationship between primary care prescribed antibiotics and the development of antibiotic resistance in perineal flora contaminating unselected urinary isolates from a large sample of asymptomatic adults representative of the general community.

PATIENTS AND METHODS

Escherichia coli isolates contaminating urine samples were obtained from asymptomatic adults aged >16 years registered with general practices in the former Avon and Gloucestershire health authority areas. Data on antibiotic exposure during the 12 months prior to providing the urine samples were collected from the primary care electronic and paper medical records. The main outcome measure was resistance to amoxicillin or trimethoprim or both.

RESULTS

Two thousand nine hundred and forty-three adults submitted urine samples. Susceptibility among E. coli isolates and antibiotic prescribing data were available from 618 patients. We found no evidence of an association between resistance and patients' exposure to any antibiotic prescribed in primary care in the previous 12 months [adjusted odds ratio (OR) 1.12, 95% confidence interval 0.77-1.65, P = 0.52]. Secondary analyses demonstrated greater resistance in patients exposed to antibiotics within 2 months (adjusted OR 1.95, 1.08-3.49, P = 0.03), a dose-response relationship to increasing exposure to trimethoprim in the previous 12 months (adjusted OR 1.01, 1.01-1.02, P = 0.001) and that individuals who had been prescribed any beta-lactam antibiotic in the previous 12 months had amoxicillin MICs more than twice (adjusted 95% CI 1.23-3.31, P = 0.009) that of those who had not been prescribed any beta-lactams.

CONCLUSIONS

Whether or not adults receive a prescription for any antibiotic during a 12 month period does not appear to influence the antimicrobial resistance of perineal flora. However, the temporal and dose-response relationships found may be suggestive of a causative association and should be the focus of further research.

Reduction in outpatient antibiotic sales for pre-school children: interrupted time series analysis of weekly antibiotic sales data in Sweden 1992–2002

OBJECTIVES

The aim of this study was to use detailed weekly data on outpatient antibiotic sales for pre-school children in Sweden to test for the significance of trends during 1992-2002. We also report on the special features found in weekly antibiotic data, and how the interrupted time series (ITS) design can adjust for this.

METHODS

Weekly data on the total number of dispensed outpatient antibiotic prescriptions to pre-school children were studied, as well as the individual subgroups commonly used to treat respiratory tract infections in children: narrow-spectrum penicillins, broad-spectrum penicillins and macrolides. In parallel, monthly data of paracetamol sales of paediatric dosages were analysed to reflect trends in symptomatic treatment. An ITS model controlling for seasonality and autocorrelation was used to examine the datasets for significant level and trend shifts.

RESULTS

A significant increase in mean and change in level could be found in the total antibiotic data in 1997, also reflected in broad-spectrum penicillin data where a similar trend break occurred in 1996. For macrolides, a trend break with a decrease in mean was noted in 1996, but no trend breaks were found in narrow-spectrum penicillin data. In contrast to the general decreasing trends in antibiotic sales, the yearly over-the-counter sales of paracetamol in paediatric preparations increased during the same period, with no identified trend breaks.

CONCLUSIONS

The overall decrease in antibiotic sales and increase in paediatric paracetamol sales might suggest that symptomatic treatment in the home has increased, as antibiotics are less commonly prescribed.

Predicting hospital rates of fluoroquinolone-resistant Pseudomonas aeruginosa from fluoroquinolone use in US hospitals and their surrounding communities

Rates of fluoroquinolone resistance among Pseudomonas aeruginosa in hospitals are increasing, but interhospital variability is great. We sought to determine whether this variability correlated to fluoroquinolone use in hospitals and in the surrounding community. Hospital quinolone use in 1999 (24 hospitals) through 2001 (35 hospitals) was determined from billing records. The number of fluoroquinolone prescriptions within a 10-mile (approximately 16-km) radius of each hospital was determined for 1999 and 2000. Hospital fluoroquinolone use increased from 1999 through 2001, from 137 to 163 defined daily doses (DDD)/1000 patient-days (P=.01). The rate of community fluoroquinolone use also increased, from 2.3 to 2.8 DDD/1000 inhabitant-days (P<.001). Rates of fluoroquinolone-resistant P. aeruginosa increased from 29% in 1999 to 36% in 2001 (P=.003). Both community and hospital fluoroquinolone use were predictive of rates of fluoroquinolone-resistant P. aeruginosa. Levofloxacin was associated with resistance, but ciprofloxacin was not. Most of the variability in resistance rates is explained by volume of fluoroquinolone use, both in the hospital and the surrounding community.

In vitro selection of resistance in haemophilus influenzae by 4 quinolones and 5 beta-lactams

We tested abilities of ciprofloxacin, levofloxacin, gatifloxacin, moxifloxacin, amoxicillin, amoxicillin/clavulanate, cefixime, cefpodoxime, and cefdinir to select resistant mutants in 5 beta-lactamase positive and 5 beta-lactamase negative Haemophilus influenzae strains by single and multistep methodology. In multistep tests, amoxicillin, amoxicillin/clavulanate and cefpodoxime exposure did not cause >4-fold minimum inhibitory concentration (MIC) increase after 50 days. One mutant selected by cefdinir had one amino acid substitution (Gly490Glu) in PBP3 and became resistant to cefdinir. Cefixime exposure caused 8-fold MIC-increase in 1 strain with TEM but the mutant remained cefixime susceptible and had no alteration in PBP3 or TEM. Among 10 strains tested, ciprofloxacin, moxifloxacin, gatifloxacin, levofloxacin caused >4-fold MIC increase in 6, 6, 5, and 2 strain, respectively. Despite the increases in quinolone MICs, none of the mutants became resistant to quinolones by established criteria. Quinolone selected mutants had quindone resistance-determining region (QRDR) alterations in GyrA, GyrB, ParC, ParE. Four quinolone mutants had no QRDR alterations. Among beta-lactams cefdinir and cefixime selected one mutant each with higher MICs however amoxicillin, amoxicillin/clavulanate, and cefpodoxime exposure did not select resistant mutants.

Excessive use of rapid tests in respiratory tract infections in Swedish primary health care

A 1-y retrospective study of problem oriented electronic patient records, for encounters concerning respiratory tract infection, was performed. The aim was to analyse the management of respiratory tract infections in primary health care in terms of diagnostic coding, tests and antibiotic treatment using data from electronic patient records. 12 primary health care centres with a registered population of 102,050 residents in 3 counties in southeast Sweden participated. Data were retrieved electronically from records of patient encounters concerning respiratory tract infections. The data were: patient age and gender, date of contact, diagnostic code, CRP and GABHS tests and results, as well as antibiotic prescriptions. In a total of 19,965 encounters, the most frequent diagnoses were common cold (40%), acute tonsillitis (18%), and acute bronchitis (15%). A total of 4445 GABHS tests (in 22% of encounters) and 6141 CRP tests (31%) were performed, and both tests were done in 1910 encounters (10%). A total of 7934 antibiotic prescriptions were registered. The proportion of patients tested and prescribed an antibiotic varied greatly between centres. We found an excessive, and much varying, use of rapid tests in encounters for respiratory tract infections. Data retrieval from electronic patient record systems was a feasible method to study the use of laboratory tests in relation to pharmacological treatment.

Presence of bacteriuria caused by trimethoprim resistant bacteria in patients prescribed antibiotics: multilevel model with practice and individual patient data

OBJECTIVE

To look for evidence of a relation between antibiotic resistance and prescribing by general practitioners by analysis of prescribing at both practice and individual patient level.

DESIGN

Repeated cross-sectional study in 1995 and 1996.

SETTING

28 general practices in the Ninewells Hospital laboratory catchment area, Tayside, Scotland. SUBJECTS REVIEWED: 8833 patients registered with the 28 practices who submitted urine samples for analysis.

MAIN OUTCOME MEASURES

Resistance to trimethoprim in bacteria isolated from urine samples at practice and individual level simultaneously in a multilevel model.

RESULTS

Practices showed considerable variation in both the prevalence of trimethoprim resistance (26-50% of bacteria isolated) and trimethoprim prescribing (67-357 prescriptions per 100 practice patients). Although variation in prescribing showed no association with resistance at the practice level after adjustment for other factors (P = 0.101), in the multilevel model resistance to trimethoprim was significantly associated with age, sex, and individual-level exposure to trimethoprim (P < 0.001) or to other antibiotics (P = 0.002). The association with trimethoprim resistance was strongest for people recently exposed to trimethoprim, and there was no association for people with trimethoprim exposure more than six months before the date of the urine sample.

DISCUSSION

Analysis of practice level data obscured important associations between antibiotic prescribing and resistance. The results support efforts to reduce unnecessary prescribing of antibiotics in the community and show the added value of individual patient data for research on the outcomes of prescribing.

Data from electronic patient records are suitable for surveillance of antibiotic prescriptions for respiratory tract infections in primary health care

Diagnoses and antibiotic treatments were analysed in relation to respiratory tract infections (RTI). A 1-y retrospective study was made of electronic patient records (EPR) for encounters concerning RTIs in primary health care in Sweden. The study covered a registered population of 102,050 individuals at 12 primary health care centres in 3 counties. Data were recorded on number of episodes, encounters, diagnostic codes and antibiotic prescriptions. The yearly number of episodes of RTIs was 16,964 or 166 per 1000 inhabitants per y. The total number of encounters was 19,965. The most frequent diagnoses were common cold (40%), acute tonsillitis (18%), and acute bronchitis (15%). The yearly number of antibiotic prescriptions was 7961, accounting for 47% of the episodes or 78 per 1000 inhabitants per y. The most frequently prescribed antibiotics were phenoxymethylpenicillin (61%), tetracyclines (18%) and macrolides 8%). Standard EPRs provide a feasible source of clinical information which, taking limitations into consideration, could be used for the follow-up of trends in antibiotic prescribing and of adherence to guidelines with regard to RTIs.