Antibacterial prescribing and antibacterial resistance in English general practice: cross sectional study

Proposed Quality Indicators for Aspects of Pediatric Acute Otitis Media Management

BACKGROUND

The high incidence of pediatric acute otitis media (AOM) makes the implications of overdiagnosis and overtreatment far-reaching. Quality indicators (QIs) for AOM are limited, drawing from generalized upper respiratory infection QIs, or locally developed benchmarks. Recognizing this, we sought to develop pediatric AOM QIs to build a foundation for future quality improvement efforts.

METHODS

Candidate indicators (CIs) were extracted from existing guidelines and position statements. The modified RAND Corporation/University of California, Los Angeles (RAND/UCLA) appropriateness methodology was used to select the final QIs by an 11-member expert panel consisting of otolaryngology-head and neck surgeons, a pediatrician and family physician.

RESULTS

Twenty-seven CIs were identified after literature review, with an additional CI developed by the expert panel. After the first round of evaluations, the panel agreed on 4 CIs as appropriate QIs. After an expert panel meeting and subsequent second round of evaluations, the panel agreed on 8 final QIs as appropriate measures of high-quality care. The 8 final QIs focus on topics of antimicrobial management, specialty referral, and tympanostomy tube counseling.

CONCLUSIONS

Evidence of variable and substandard care persists in the diagnosis and management of pediatric AOM despite the existence of high-quality guidelines. This study proposes 8 QIs which compliment guideline recommendations and are meant to facilitate future quality improvement initiatives that can improve patient outcomes.

A multifaceted intervention to reduce antibiotic prescribing among CHIldren with acute COugh and respiratory tract infection: the CHICO cluster RCT

Background

Clinical uncertainty in primary care regarding the prognosis of children with respiratory tract infections contributes to the unnecessary use of antibiotics. Improved identification of children at low risk of future hospitalisation might reduce clinical uncertainty. A National Institute for Health and Care Research-funded 5-year programme (RP-PG-0608-10018) was used to develop and feasibility test an intervention.

Objectives

The aim of the children with acute cough randomised controlled trial was to reduce antibiotic prescribing among children presenting with acute cough and respiratory tract infection without increasing hospital admission.

Design

An efficient, pragmatic open-label, two-arm trial (with embedded qualitative and health economic analyses) using practice-level randomisation using routinely collected data as the primary outcome.

Setting

General practitioner practices in England.

Participants

General practitioner practices using the Egton Medical Information Systems® patient-record system for children aged 0-9 years presenting with a cough or upper respiratory tract infection. Recruited by Clinical Research Networks and Clinical Commissioning Groups.

Intervention

Comprised: (1) elicitation of parental concerns during consultation; (2) a clinician-focused prognostic algorithm to identify children with acute cough and respiratory tract infection at low, average or elevated risk of hospitalisation in the next 30 days accompanied by prescribing guidance, (3) provision of a printout for carers including safety-netting advice.

Main outcome measures

Co-primaries using the practice list-size for children aged 0-9 years as the denominator: rate of dispensed amoxicillin and macrolide items at each practice (superiority comparison) from NHS Business Services Authority ePACT2 and rate of hospital admission for respiratory tract infection (non-inferiority comparison) from Clinical Commissioning Groups, both routinely collected over 12 months.

Results

Of the 310 practices required, 294 (95%) were recruited (144 intervention and 150 controls) with 336,496 registered 0-9-year-olds (5% of all 0-9-year-old children in England) from 47 Clinical Commissioning Groups. Included practices were slightly larger than those not included, had slightly lower baseline dispensing rates and were located in more deprived areas (reflecting the distribution for practice postcodes nationally). Twelve practices (4%) subsequently withdrew (six related to the pandemic). The median number of times the intervention was used was 70 per practice (by a median of 9 clinicians) over 12 months. There was no evidence that the antibiotic dispensing rate in the intervention practices [0.155 (95% confidence interval 0.135 to 0.179)] differed to controls [0.154 (95% confidence interval 0.130 to 0.182), relative risk= 1.011 (95% confidence interval 0.992 to 1.029); p = 0.253]. There was, overall, a reduction in dispensing levels and intervention usage during the pandemic. The rate of hospitalisation for respiratory tract infection in the intervention practices [0.019 (95% confidence interval 0.014 to 0.026)] compared to the controls [0.021 (95% confidence interval 0.014 to 0.029)] was non-inferior [relative risk = 0.952 (95% confidence interval 0.905 to 1.003)]. The qualitative evaluation found the clinicians liked the intervention, used it as a supportive aid, especially with borderline cases but that it, did not always integrate well within the consultation flow and was used less over time. The economic evaluation found no evidence of a difference in mean National Health Service costs between arms; mean difference -£1999 (95% confidence interval -£6627 to 2630).

Conclusions

The intervention was feasible and subjectively useful to practitioners, with no evidence of harm in terms of hospitalisations, but did not impact on antibiotic prescribing rates.

Future work and limitations

Although the intervention does not appear to change prescribing behaviour, elements of the approach may be used in the design of future interventions.

Trial registration

This trial is registered as ISRCTN11405239 (date assigned 20 April 2018) at www.controlled-trials.com (accessed 5 September 2022). Version 4.0 of the protocol is available at: https://www.journalslibrary.nihr.ac.uk/ (accessed 5 September 2022).

Funding

This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment (NIHR award ref: 16/31/98) programme and is published in full in Health Technology Assessment; Vol. 27, No. 32. See the NIHR Funding and Awards website for further award information.

Multi-faceted intervention to improve management of antibiotics for children presenting to primary care with acute cough and respiratory tract infection (CHICO): efficient cluster randomised controlled trial

OBJECTIVE

To assess whether an easy-to-use multifaceted intervention for children presenting to primary care with respiratory tract infections would reduce antibiotic dispensing, without increasing hospital admissions for respiratory tract infection.

DESIGN

Two arm randomised controlled trial clustered by general practice, using routine outcome data, with qualitative and economic evaluations.

SETTING

English primary care practices using the EMIS electronic medical record system.

PARTICIPANTS

Children aged 0-9 years presenting with respiratory tract infection at 294 general practices, before and during the covid-19 pandemic.

INTERVENTION

Elicitation of parental concerns during consultation; a clinician focused prognostic algorithm to identify children at very low, normal, or elevated 30 day risk of hospital admission accompanied by antibiotic prescribing guidance; and a leaflet for carers including safety netting advice.

MAIN OUTCOME MEASURES

Rate of dispensed amoxicillin and macrolide antibiotics (superiority comparison) and hospital admissions for respiratory tract infection (non-inferiority comparison) for children aged 0-9 years over 12 months (same age practice list size as denominator).

RESULTS

Of 310 practices needed, 294 (95%) were randomised (144 intervention and 150 controls) representing 5% of all registered 0-9 year olds in England. Of these, 12 (4%) subsequently withdrew (six owing to the pandemic). Median intervention use per practice was 70 (by a median of 9 clinicians). No evidence was found that antibiotic dispensing differed between intervention practices (155 (95% confidence interval 138 to 174) items/year/1000 children) and control practices (157 (140 to 176) items/year/1000 children) (rate ratio 1.011, 95% confidence interval 0.992 to 1.029; P=0.25). Pre-specified subgroup analyses suggested reduced dispensing in intervention practices with fewer prescribing nurses, in single site (compared with multisite) practices, and in practices located in areas of lower socioeconomic deprivation, which may warrant future investigation. Pre-specified sensitivity analysis suggested reduced dispensing among older children in the intervention arm (P=0.03). A post hoc sensitivity analysis suggested less dispensing in intervention practices before the pandemic (rate ratio 0.967, 0.946 to 0.989; P=0.003). The rate of hospital admission for respiratory tract infections in the intervention practices (13 (95% confidence interval 10 to 18) admissions/1000 children) was non-inferior compared with control practices (15 (12 to 20) admissions/1000 children) (rate ratio 0.952, 0.905 to 1.003).

CONCLUSIONS

This multifaceted antibiotic stewardship intervention for children with respiratory tract infections did not reduce overall antibiotic dispensing or increase respiratory tract infection related hospital admissions. Evidence suggested that in some subgroups and situations (for example, under non-pandemic conditions) the intervention slightly reduced prescribing rates but not in a clinically relevant way.

TRIAL REGISTRATION

ISRCTN11405239ISRCTN registry ISRCTN11405239.

Antibiotic prescription: Knowledge among physicians and nurses in western Sweden

Misuse and overuse of antibiotics are common in primary care. Guidelines for prescribing of antibiotics are often not followed We conducted a survey of 120 health centers in western Sweden to investigate to what extent physicians and nurses think they know and comply with the guidelines for prescribing of antibiotics. A large majority of the respondents answered that they know the guidelines well. However, many also believed that physicians/nurses in general know less about and are worse at following the guidelines than themselves, indicating optimism bias. According to the respondents the main reason for non-compliance with guidelines was patient expectations. The survey also showed that both physicians' and nurses' actual knowledge of when it is effective to prescribe antibiotics is incomplete. Interventions to reduce unnecessary antibiotic therapy in primary care should target the failing congruence between the perceived knowledge of guidelines for antibiotic therapy and actual knowledge.

E. coli bacteraemia and antimicrobial resistance following antimicrobial prescribing for urinary tract infection in the community

Background

Urinary tract infections are one of the most common infections in primary and secondary care, with the majority of antimicrobial therapy initiated empirically before culture results are available. In some cases, however, over 40% of the bacteria that cause UTIs are resistant to some of the antimicrobials used, yet we do not know how the patient outcome is affected in terms of relapse, treatment failure, progression to more serious illness (bacteraemia) requiring hospitalization, and ultimately death. This study analyzed the current patterns of antimicrobial use for UTI in the community in Scotland, and factors for poor outcomes.

Objectives

To explore antimicrobial use for UTI in the community in Scotland, and the relationship with patient characteristics and antimicrobial resistance in E. coli bloodstream infections and subsequent mortality.

Methods

We included all adult patients in Scotland with a positive blood culture with E. coli growth, receiving at least one UTI-related antimicrobial (amoxicillin, amoxicillin/clavulanic acid, ciprofloxacin, trimethoprim, and nitrofurantoin) between 1st January 2009 and 31st December 2012. Univariate and multivariate logistic regression analysis was performed to understand the impact of age, gender, socioeconomic status, previous community antimicrobial exposure (including long-term use), prior treatment failure, and multi-morbidity, on the occurrence of E. coli bacteraemia, trimethoprim and nitrofurantoin resistance, and mortality.

Results

There were 1,093,227 patients aged 16 to 100 years old identified as receiving at least one prescription for the 5 UTI-related antimicrobials during the study period. Antimicrobial use was particularly prevalent in the female elderly population, and 10% study population was on long-term antimicrobials. The greatest predictor for trimethoprim resistance in E. coli bacteraemia was increasing age (OR 7.18, 95% CI 5.70 to 9.04 for the 65 years old and over group), followed by multi-morbidity (OR 5.42, 95% CI 4.82 to 6.09 for Charlson Index 3+). Prior antimicrobial use, along with prior treatment failure, male gender, and higher deprivation were also associated with a greater likelihood of a resistant E. coli bacteraemia. Mortality was significantly associated with both having an E. coli bloodstream infection, and those with resistant growth.

Conclusion

Increasing age, increasing co-morbidity, lower socioeconomic status, and prior community antibiotic exposure were significantly associated with a resistant E. coli bacteraemia, which leads to increased mortality.

Antibiotic use and deprivation: an analysis of Welsh primary care antibiotic prescribing data by socioeconomic status

OBJECTIVES

To examine the association between socioeconomic status (SES) and antibiotic prescribing, controlling for the presence of common chronic conditions and other potential confounders and variation amongst GP practices and clusters.

METHODS

This was an electronic cohort study using linked GP and Welsh Index of Multiple Deprivation (WIMD) data. The setting was GP practices contributing to the Secure Anonymised Information Linkage (SAIL) Databank 2013-17. The study involved 2.9 million patients nested within 339 GP practices, nested within 67 GP clusters.

RESULTS

Approximately 9 million oral antibiotics were prescribed between 2013 and 2017. Antibiotic prescribing rates were associated with WIMD quintile, with more deprived populations receiving more antibiotics. This association persisted after controlling for patient demographics, smoking, chronic conditions and clustering by GP practice and cluster, with those in the most deprived quintile receiving 18% more antibiotic prescriptions than those in the least deprived quintile (incidence rate ratio = 1.18; 95% CI = 1.181-1.187). We found substantial unexplained variation in antibiotic prescribing rates between GP practices [intra-cluster correlation (ICC) = 47.31%] and GP clusters (ICC = 12.88%) in the null model, which reduced to ICCs of 3.50% and 0.85% for GP practices and GP clusters, respectively, in the final adjusted model.

CONCLUSIONS

Antibiotic prescribing in primary care is increased in areas of greater SES deprivation and this is not explained by differences in the presence of common chronic conditions or smoking status. Substantial unexplained variation in prescribing supports the need for ongoing antimicrobial stewardship initiatives.

Interventions for prudent antibiotic use in primary healthcare: an econometric analysis

Background

Rational antibiotic prescribing is crucial to combat antibiotic resistance. Optimal strategies to improve antibiotic use are not known. Strama, the Swedish strategic program against antibiotic resistance, has been successful in reducing antibiotic prescription rates. This study investigates whether two specific interventions directed toward healthcare centers, an informational visit and a self-evaluation meeting, played a role in observed reduction in rates of antibiotic prescriptions in primary healthcare.

Methods

The study was a retrospective, observational, empirical analysis exploiting the variation in the timing of the interventions and considering past prescriptions through use of estimations from dynamic panel data models. Primary healthcare data from 2011 to 2014 were examined. Data were from public and private primary healthcare centers in western Sweden. The key variables were prescription of antibiotics and indicator variables for the two interventions.

Results

The first intervention, an educational information intervention, decreased the number of prescriptions among public healthcare centers, but this effect was only temporary. We found no proof that the second intervention, a self-evaluation meeting at the healthcare center, had an impact on the reduction of prescriptions.

Conclusions

Single educational interventions aimed at influencing rates of antibiotic prescriptions have limited impact. A multifaceted approach is needed in efforts to reduce the use of antibiotics in primary health care.

Antimicrobial resistance associations with national primary care antibiotic stewardship policy: Primary care-based, multilevel analytic study

Background

Recent UK antibiotic stewardship policies have resulted in significant changes in primary care dispensing, but whether this has impacted antimicrobial resistance is unknown.

Aim

To evaluate associations between changes in primary care dispensing and antimicrobial resistance in community-acquired urinary Escherichia coli infections.

Methods

Multilevel logistic regression modelling investigating relationships between primary care practice level antibiotic dispensing for approximately 1.5 million patients in South West England and resistance in 152,704 community-acquired urinary E. coli between 2013 and 2016. Relationships presented for within and subsequent quarter drug-bug pairs, adjusted for patient age, deprivation, and rurality.

Results

In line with national trends, overall antibiotic dispensing per 1000 registered patients fell 11%. Amoxicillin fell 14%, cefalexin 20%, ciprofloxacin 24%, co-amoxiclav 49% and trimethoprim 8%. Nitrofurantoin increased 7%. Antibiotic reductions were associated with reduced within quarter same-antibiotic resistance to: amoxicillin, ciprofloxacin and trimethoprim. Subsequent quarter reduced resistance was observed for trimethoprim and amoxicillin. Antibiotic dispensing reductions were associated with increased within and subsequent quarter resistance to cefalexin and co-amoxiclav. Increased nitrofurantoin dispensing was associated with reduced within and subsequent quarter trimethoprim resistance without affecting nitrofurantoin resistance.

Conclusions

This evaluation of a national primary care stewardship policy on antimicrobial resistance in the community suggests both hoped-for benefits and unexpected harms. Some increase in resistance to cefalexin and co-amoxiclav could result from residual confounding. Randomised controlled trials are urgently required to investigate causality.

The distribution of antibiotic use and its association with antibiotic resistance

Antibiotic use is a primary driver of antibiotic resistance. However, antibiotic use can be distributed in different ways in a population, and the association between the distribution of use and antibiotic resistance has not been explored. Here, we tested the hypothesis that repeated use of antibiotics has a stronger association with population-wide antibiotic resistance than broadly-distributed, low-intensity use. First, we characterized the distribution of outpatient antibiotic use across US states, finding that antibiotic use is uneven and that repeated use of antibiotics makes up a minority of antibiotic use. Second, we compared antibiotic use with resistance for 72 pathogen-antibiotic combinations across states. Finally, having partitioned total use into extensive and intensive margins, we found that intense use had a weaker association with resistance than extensive use. If the use-resistance relationship is causal, these results suggest that reducing total use and selection intensity will require reducing broadly distributed, low-intensity use.

Treatment of Acute Otitis Media in the Pediatric Emergency Department

BACKGROUND

Over-treatment of acute otitis media (AOM) with antibiotics is common, and poses a high burden on health-care systems.

METHODS

Records of children 6-36 months of age with AOM visiting a university-affiliated pediatric emergency department between 2014 and 2016 were reviewed for the treatment given: watchful waiting versus antibiotics. If antibiotics were prescribed, the type and duration were recorded. We evaluated appropriate and inappropriate treatment rates of eligible AOM cases, in respect to the local guidelines, which encourage watchful waiting in most mild-moderate cases.

RESULTS

Out of 1493 AOM visits, 863 (57.8%) were boys, with a median age of 14.9 months (interquartile range, 9-19). The overall pre-visit antibiotic rate was 24.1%, but among those children examined by a physician, this rate was 95.2%. Amoxicillin was the most common antibiotic, administered in 66.3% of the cases. Only 21 children (5.8%) had been treated with antibiotics for ≥7 days before their visit, and were considered as treatment failure. Antibiotic therapy upon discharge was recorded in 1394/1449 visits (96.2%), again with amoxicillin as the most common antibiotic therapy, in 80.8% of the cases. In these visits, the average duration of antibiotic treatment was 8.29 days. Appropriateness of treatment (watchful waiting or antibiotics) could be analyzed in 1134 visits; 20.9% were considered as inappropriate. Of them, 98.3% were prescribed with the wrong antibiotic type and duration.

CONCLUSIONS

Adherence rate to the local guidelines treatment recommendations for uncomplicated AOM was high, as measured by whether appropriate treatment was given and type and duration of antibiotics.

Tobacco Smoking as a Risk Factor for Increased Antibiotic Prescription

INTRODUCTION

Antibiotic resistance is rapidly spreading, affecting millions of people and costing billions of dollars. Potential factors affecting antibiotic prescription, such as tobacco use, could dramatically influence this public health crisis. The study determined the magnitude of impact that tobacco use has on antibiotic prescribing patterns.

METHODS

Pooled data were analyzed in 2015 from the 2006-2010 National Ambulatory Medical Care Survey, a cross-sectional survey describing use of ambulatory medical services in the U.S. via healthcare provider-patient encounters. Patients aged >18 years with documented tobacco use status diagnosed with an infection were included (i.e., all encounters in the analysis included an infectious diagnosis of interest). The analytic sample included 8,307 visits, representing 294 million visits nationally.

RESULTS

Half (49.9%) of encounters that included any infection had an antibiotic prescribed. Adjusted odds of receiving antibiotics among current tobacco users was 1.20 (95% CI=1.02, 1.42), and even higher for encounters of respiratory infections (AOR=1.31, 95% CI=1.05, 1.62). Antibiotic prescription rates were lower among patients aged >65 years, those with comorbid asthma or cancer, non-whites, and those covered by Medicaid and higher for primary care physicians.

CONCLUSIONS

Despite lack of evidence-based rationale, among a national sample of patients with an infectious diagnosis, tobacco users had 20%-30% higher odds of receiving antibiotics than non-tobacco users. This is the first U.S. study to quantify the magnitude of this unsubstantiated practice. Prescribers should understand that tobacco use could be associated with higher antibiotic prescription, which may subsequently increase antimicrobial resistance in the community.

Clinical predictors of antibiotic prescribing for acutely ill children in primary care: an observational study

BACKGROUND

Antibiotic overuse and inappropriate prescribing drive antibiotic resistance. Children account for a high proportion of antibiotics prescribed in primary care.

AIM

To determine the predictors of antibiotic prescription in young children presenting to UK general practices with acute illness.

DESIGN AND SETTING

Prospective observational study in general practices in Wales.

METHOD

A total of 999 children were recruited from 13 practices between March 2008 and July 2010. Multilevel, multivariable logistic regression analysis was performed to determine predictors of antibiotic prescribing.

RESULTS

Oral antibiotics were prescribed to 261 children (26.1%). Respiratory infections were responsible for 77.4% of antibiotic prescriptions. The multivariable model included 719 children. Children were more likely to be prescribed antibiotics if they were older (odds ratio [OR] 1.3; 95% confidence intervals [CI] = 1.1 to 1.7); presented with poor sleep (OR 2.7; 95% CI = 1.5 to 5.0); had abnormal ear (OR 6.5; 95% CI = 2.5 to 17.2), throat (OR 2.2; 95% CI = 1.1 to 4.5) or chest examination (OR 13.6; 95% CI = 5.8 to 32.2); were diagnosed with lower respiratory tract infection (OR 9.5; 95% CI = 3.7 to 25.5), tonsillitis/sore throat (OR 119.3; 95% CI = 28.2 to 504.6), ear infection (OR 26.5; 95% CI = 7.4 to 95.7) or urinary tract infection (OR 12.7; 95% CI = 4.4 to 36.5); or if the responsible clinician perceived the child to be moderately to severely unwell (OR 4.0; 95% CI = 1.4 to 11.4). The area under the receiver operating characteristic curve was 0.9371.

CONCLUSION

Respiratory infections were responsible for 74.4% of antibiotic prescriptions. Diagnoses of tonsillitis, sore throat, or ear infection were associated most with antibiotic prescribing. Diagnosis seemed to be more important than abnormal examination findings in predicting antibiotic prescribing, although these were correlated.

Acute otitis media in children-current treatment and prevention

Acute otitis media (AOM) is the most common bacterial infection in children and has a very varied clinical spectrum, ranging from spontaneous resolutions to serious complications. The effect of antibiotics in AOM depends on the chosen outcome, but has been shown to reduce pain somewhat, and have a greater beneficial effect in severe cases of AOM. Today, not all episodes of AOM are treated with antibiotics, but most countries have issued guidelines that include an option of watchful waiting in many cases. Prevention of AOM reaches from modification of environmental risk factors to vaccinations and surgery. Conjugate pneumococcal vaccines and influenza vaccines have been shown to somewhat reduce the number of AOM episodes in different groups of children. Grommets, with or without adenoidectomy, are effective at least during the first 6 months after surgery.

Patient Attitudes and Patterns of Self-Medication with Antibiotics – A Cross-Sectional Study in Bulgaria

BACKGROUND: Self-medication with antibiotics is a major concern worldwide because of the high risks of antimicrobial resistance which may result in complicated courses of treatment, increased risk of death and excess costs to the healthcare systems.AIM: The aim was to study the attitudes and self-medication patterns as related to the use of antibiotics among the general Bulgarian population and their determinants.MATERIALS AND METHODS: A questionnaire-based survey was performed among the patients in two randomly selected municipalities. The questionnaire was mailed to 50 randomly selected adult patients by each of the 33 responding GPs thus addressing a total of 1650 participants.RESULTS: A total of 1050 patients completed and returned the questionnaire. The observed self-medication rate was 43%. The women and the younger employees and students tended to have a higher self-medication rate. Fever (22%), sore throat and cough (12.7%) and discomfort when urinating (8.2%) were the most frequent patterns related to the practice of self-medication.CONCLUSION: This analysis reported an extensive use of self-medication with antibiotics in the study population before the changes in the Bulgarian legislation. Younger age and social status (students, employed) were the most important socio-demographic patterns that had probably led towards self-medication with antibiotics.

Streptococcus pneumoniae non-susceptibility and outpatient antimicrobial prescribing rates at the Alaska Native Medical Center

Background

American Indian/Alaska Native (AI/AN) people suffer substantially higher rates of invasive pneumococcal disease (IPD) than the general US population. We evaluated antimicrobial prescribing data and their association with non-susceptibility in Streptococcus pneumoniae causing IPD in AI/AN people between 1992 and 2009.

Methods

Antimicrobial use data were gathered from the electronic patient management system and included all prescriptions dispensed to Alaska Native patients aged 5 years and older from outpatient pharmacies at the Alaska Native Medical Center (ANMC). Antimicrobial susceptibility data were gathered from pneumococcal isolates causing IPD among Anchorage Service Unit AI/AN residents aged 5 years and older. Data were restricted to serotypes not contained in the pneumococcal vaccine (PCV7).

Results

Over the study period, overall antimicrobial prescribing increased 59% (285/1,000 persons/year in 1992 to 454/1,000 persons per year in 2009, p<0.001). Trimethoprim/sulfamethoxazole prescribing increased (43/1,000 persons/year in 1992 to 108/1,000 persons/year in 2009, p<0.001) and non-susceptibility to trimethoprim/sulfamethoxazole in AI/AN patients ≥5 years of age increased in non-PCV7 serotypes (0–12%, p<0.05). Similarly, prescribing rates increased for macrolide antibiotics (46/1,000 persons/year in 1992 to 84/1,000 persons/year in 2009, p<0.05). We observed no statistically significant change over time in erythromycin non-susceptibility among non-PCV7 serotypes in AI/AN patients aged 5 years or greater (0–7%, p=0.087).

Conclusion

Antimicrobial prescribing patterns of some antibiotics in the AI/AN population corresponded to increased antimicrobial resistance in clinical isolates. This study highlights the on-going threat of antimicrobial resistance, the critical importance of judicious prescribing of antibiotics and the potential utility of prescribing data for addressing this issue.

The TARGET cohort study protocol: a prospective primary care cohort study to derive and validate a clinical prediction rule to improve the targeting of antibiotics in children with respiratory tract illnesses

Background

Children with respiratory tract infections are the single most frequent patient group to make use of primary care health care resources. The use of antibiotics remains highly prevalent in young children, but can lead to antimicrobial resistance as well as reinforcing the idea that parents should re-consult for similar symptoms. One of the main drivers of indiscriminate antimicrobial use is the lack of evidence for, and therefore uncertainty regarding, which children are at risk of poor outcome. This paper describes the protocol for the TARGET cohort study, which aims to derive and validate a clinical prediction rule to identify children presenting to primary care with respiratory tract infections who are at risk of hospitalisation.

Methods/design

The TARGET cohort study is a large, multicentre prospective observational study aiming to recruit 8,300 children aged ≥3 months and <16 years presenting to primary care with a cough and respiratory tract infection symptoms from 4 study centres (Bristol, London, Oxford and Southampton). Following informed consent, symptoms, signs and demographics will be measured. In around a quarter of children from the Bristol centre, a single sweep, dual bacterial-viral throat swab will be taken and parents asked to complete a symptom diary until the child is completely well or for 28 days, whichever is sooner. A review of medical notes including clinical history, re-consultation and hospitalisations will be undertaken. Multivariable logistic regression will be used to identify the independent clinical predictors of hospitalisation as well as the prognostic significance of upper respiratory tract microbes. The clinical prediction rule will be internally validated using various methods including bootstrapping.

Discussion

The clinical prediction rule for hospitalisation has the potential to help identify a small group of children for hospitalisation and a much larger group where hospitalisation is very unlikely and antibiotic prescribing would be less warranted. This study will also be the largest natural history study to date of children presenting to primary care with acute cough and respiratory tract infections, and will provide important information on symptom duration, re-consultations and the microbiology of the upper respiratory tract.

The use of serial point-prevalence studies to investigate hospital anti-infective prescribing

Objectives

To develop and test an efficient, reproducible method for the surveillance of hospital anti-infective use; to use this method to investigate patterns of anti-infective prescribing.

Method

A series of three standardised point-prevalence studies were carried out in which pharmacists recorded details of all inpatients prescribed systemic anti-infectives. Time taken to collect, enter and analyse these data was documented. Parameters examined included: percentage of patients prescribed anti-infectives, percentage of anti-infectives that were for “reserved” use, percentage of these with appropriate approval, percentage of anti-infectives administered intravenously, duration of therapy, and combinations of anti-infectives used.

Setting

All hospital inpatients in a large National Health Service (NHS) Trust comprising four sites.

Key findings

For each study, an estimated 35 additional hours of pharmacists' time was required for data collection, cleaning and analysis, and 15 hours for data entry. The method developed was easily reproducible and results from the three studies were very similar. Overall, 33 per cent of 2,656 inpatients were prescribed at least one anti-infective (mean 1.7 per patient); 48 per cent of anti-infectives were given intravenously (IV), of which 34 per cent could have been given orally. Of the anti-infectives used, 21 per cent were for “reserved” use. Of these, 65 per cent were used for an approved indication, and 11 per cent were not. The remaining 24 per cent had no indication documented in the medical notes.

Conclusion

This is a practical method for studying hospital anti-infective use in the absence of computerised prescribing. The database produced provides a wealth of information and various targets for intervention have been identified; these can now be evaluated against the baseline data collected. The methods developed could be used in other hospitals to provide benchmarking data.

Relative impact of clinical evidence and over-the-counter prescribing on topical antibiotic use for acute infective conjunctivitis

BACKGROUND

Acute infective conjunctivitis is a common presentation in general practice. In 2005, three placebo-controlled clinical trials showed that use of topical antibiotics had a small effect on time to clinical resolution. In the same year, chloramphenicol eye drops were made available for sale over the counter.

AIM

To compare the relative impact of clinical trial evidence and a change to over-the-counter availability on community use of topical chloramphenicol.

DESIGN OF STUDY

Observational study using mainly routinely collected data for England.

SETTING

National prescribing data for England and local data from general practices in Oxfordshire, England.

METHOD

Data were collated from three sources: GP prescriptions from the Prescription Pricing Authority, wholesale supply to pharmacists from IMS Health, and an audit of delayed prescribing and non-prescribing from electronic consultation records for acute conjunctivitis, in four general practices.

RESULTS

The number of general practice prescriptions for topical chloramphenicol fell from 2.3 million in 2004 to 1.9 million in 2007, a reduction of 15.5%. In contrast, over-the-counter sales by pharmacists have increased steadily. The net effect of these changes has been a 47.8% increase in total chloramphenicol use during 2005-2007, with 1.1 million additional packs being used in 2007 compared to 2004.

CONCLUSION

Making an antibiotic available over the counter increases its use substantially. This is in conflict with the important public health message that antibiotic use needs to be reduced to combat resistance. These findings support the views of the Chief Medical Officer that no more antibiotics should currently be made available over the counter.

A multilevel analysis of trimethoprim and ciprofloxacin prescribing and resistance of uropathogenic Escherichia coli in general practice

OBJECTIVES

A retrospective analysis of databases was performed to describe trimethoprim and ciprofloxacin prescribing and resistance in Escherichia coli within general practices in the West of Ireland from 2004 to 2008.

METHODS

Antimicrobial susceptibility testing was performed by disc diffusion methods according to the CLSI methods and criteria on significant E. coli isolates (colony count >10(5) cfu/mL) from urine samples submitted from general practice. Data were collected over a 4.5 year period and aggregated at practice level. Data on antimicrobial prescribing of practices were obtained from the national Irish prescribing database, which accounts for approximately 70% of all medicines prescribed in primary care. A multilevel model (MLwiN) was fitted with trimethoprim/ciprofloxacin resistance rates as outcome and practice prescribing as predictor. Practice and individual routinely collected variables were controlled for in the model.

RESULTS

Seventy-two general practices sent between 13 and 720 (median 155) samples that turned out to be E. coli positive. Prescribing at practice level was significantly correlated with the probability of antimicrobial-resistant E. coli with an odds ratio of 1.02 [95% confidence interval (CI) 1.01-1.04] for every additional prescription of trimethoprim per 1000 patients per month in the practice and 1.08 (1.04-1.11) for ciprofloxacin. Age was a significant risk factor in both models. Higher variation between practices was found for ciprofloxacin as well as a yearly increase in resistance. Comparing a 'mean' practice with 1 prescription per month with one with 10 prescriptions per month showed an increase in predicted probability of a resistant E. coli for the 'mean' patient from 23.9% to 27.5% for trimethoprim and from 3.0% to 5.5% for ciprofloxacin.

CONCLUSIONS

A higher level of antimicrobial prescribing in a practice is associated with a higher probability of a resistant E. coli for the patient. The variation in antimicrobial resistance levels between practices was relatively higher for ciprofloxacin than for trimethoprim.

Treatment of infection: a cross-sectional survey of antibiotic drug utilisation in the Ramallah district of Palestine

Objective

To characterise the use of antibiotics in outpatients treated for infection in the Ramallah district of Palestine.

Setting

A purposive sample of general and specialist outpatient clinics in the public and private sector in Ramallah.

Method

A prospective, cross-sectional survey over 3 months (February-May 2000) of patients diagnosed with infection, conducted through questionnaires to treating physicians (n = 25) and patients (n = 575).

Key findings

Infection associated with the respiratory tract was the most common type of infection diagnosed, accounting for over 80% of all infections, followed by urinary tract infection and otitis media (14% and 10%, respectively). Amoxicillin was the antibiotic prescribed most often, prescribed for 44% of all patients and for infection of all types and across all age groups. A wide variety of other antibiotics was prescribed, and in the private sector there was more use of newer, more expensive antibiotics. Antibiotic use was rated as appropriate in only 35% of patients, with inappropriate prescribing largely resulting from inappropriate indication (73%) and to a lesser extent choice of drug (17%) or cost (9%). Duration of therapy was seldom specified by the prescriber and depended on pack size dispensed. Seventy-six per cent of patients followed up at 1 week had recovered partially or completely, but lack of compliance was noted in 30%.

Conclusions

There was considerable evidence of inappropriate use of antibiotics, including prescribing for likely self-limiting or non-bacterial infection and failure to specify duration of therapy. A number of patients failed to complete the course. Strategies to promote optimal antibiotic use should be targeted initially to respiratory tract infection, and both physicians and patients require educational input. The community pharmacist can play a lead role on account of both drug expertise and ability to advise health professionals and patients.

Curbing the menace of antimicrobial resistance in developing countries

Several reports suggest that antimicrobial resistance is an increasing global problem; but like most pandemics, the greatest toll is in the less developed countries. The dismally low rate of discovery of antimicrobials compared to the rate of development of antimicrobial resistance places humanity on a very dangerous precipice. Since antimicrobial resistance is part of an organism's natural survival instinct, total eradication might be unachievable; however, it can be reduced to a level that it no longer poses a threat to humanity. While inappropriate antimicrobial consumption contributes to the development of antimicrobial resistance, other complex political, social, economic and biomedical factors are equally important. Tackling the menace therefore should go beyond the conventional sensitization of members of the public and occasional press releases to include a multi-sectoral intervention involving the formation of various alliances and partnerships. Involving civil society organisations like the media could greatly enhance the success of the interventions

Individualized population care: linking personal care to population care in general practice

BACKGROUND

General practice is increasingly expected to deliver population care to individual patients. The feasibility and ethics of this policy shift have been challenged.

AIM

Our aim is to suggest how to deliver population care while protecting personal care.

METHODS

We outline and discuss concepts of these types of care, their relation to the prevailing discourse regarding intervention benefits, and arguments for individualized population care.

RESULTS

Individualized population care can enable general practice to meet the health targets of individual patients in the light of population-based goals. It unifies the concepts of personal care and whole population care. Personal care focuses on the individual good in particular consultations. Whole population care focuses on the overall health good of a population without reference to the individuality of each population member. These types of care constitute elements of a continuum that varies in purpose and objects of focus. The limitations of a crude dichotomy of personal care and population care are made explicit in a series of five arguments that lend support to the concept of individualized population care.

CONCLUSIONS

We advocate a constructive but critical attitude towards the idea of population-based interventions in everyday general practice. Traditional personal care and whole population care can theoretically be integrated into individualized population care. However, this presupposes clinical-epidemiological expertise and moral awareness in practising clinicians.

Antibiotic prescribing patterns and hospital admissions with respiratory and urinary tract infections

OBJECTIVE

To explore the relationship between antibiotic prescribing indicators for assessing the prescribing quality of general practitioners (GPs) and populations' health outcome indicators.

DESIGN

Descriptive cross-sectional study.

SETTING

Aljarafe Primary Health Care Area (population 321,034) under the administrative jurisdiction of the Andalusian Public Health Care Service, Spain. In total, 162 GPs, representing 95.29% of the total number of GPs in the study area, were included in the analysis.

METHODS

Antibiotic prescribing indicators based on clinical evidence and recommendations from local resistance patterns were chosen by the consensus group technique. Hospital admissions due to respiratory tract and urinary infections in the three hospitals of the study area were recorded. Multiple regression analysis was carried out to determine the relationship between community prescribing of antibiotics and hospital admissions due to serious complications from respiratory and urinary infections.

RESULTS

The higher prescribing of antibiotics adjusted for patients and working days was associated with a significantly higher number of adjusted hospital admissions due complications arising from respiratory and urinary infections (p < 0.001) (R (2) = 0.142). This relationship was not found for indicators based on the relative prescribing of recommended first-line versus second and third-line antibiotics. There were fewer patients of women GPs admitted to hospitals (p = 0.021).

CONCLUSIONS

Our findings show a statistically significant relationship-at the GPs level-between the quantitative antibiotic prescribing rate and standardized hospital admissions due to complications arising from respiratory and urinary infections of the assisted patients. Strategies should be addressed to reduce unnecessary antibiotic prescribing in primary care.

Containing antibiotic resistance: decreased antibiotic-resistant coliform urinary tract infections with reduction in antibiotic prescribing by general practices

BACKGROUND

GPs are urged to prescribe antibiotics less frequently, despite lack of evidence linking reduced antibiotic prescribing with reductions in resistance at a local level.

AIM

To investigate associations between changes in antibiotic dispensing and changes in antibiotic resistance at general-practice level.

DESIGN OF STUDY

Seven-year study of dispensed antibiotics and antibiotic resistance in coliform isolates from urine samples routinely submitted from general practice.

SETTING

General practices in Wales.

METHOD

Multilevel modelling of trends in resistance to ampicillin and trimethoprim, and changes in practice total antibiotic dispensing and amoxicillin and trimethoprim dispensing.

RESULTS

The primary analysis included data on 164 225 coliform isolates from urine samples submitted from 240 general practices over the 7-year study period. These practices served a population of 1.7 million patients. The quartile of practices that had the greatest decrease in total antibiotic dispensing demonstrated a 5.2% reduction in ampicillin resistance over the 7-year period with changes of 0.4%, 2.4%, and -0.3% in the other three quartiles. There was a statistically significant overall decrease in ampicillin resistance of 1.03% (95% confidence interval [CI] = 0.37 to 1.67%) per decrease of 50 amoxicillin items dispensed per 1000 patients per annum. There were also significant reductions in trimethoprim resistance in the two quartiles of practices that reduced total antibiotic dispensing most compared with those that reduced it least, with an overall decrease in trimethoprim resistance of 1.08% (95% CI = 0.065 to 2.10%) per decrease of 20 trimethoprim items dispensed per 1000 patients per annum. Main findings were confirmed by secondary analyses of 256 370 isolates from 527 practices that contributed data at some point during the study period.

CONCLUSION

Reducing antibiotic dispensing at general-practice level is associated with reduced local antibiotic resistance. These findings should further encourage clinicians and patients to use antibiotics conservatively.

The state of play in the battle against antimicrobial resistance: a general practitioner perspective

This article summarizes personal reflections from the perspective of general practice on developments with regard to antibiotic resistance and the containment of antibiotic prescribing during the lifetime of the Specialist Advisory Committee on Antimicrobial Resistance in England. These reflections concern the entry of antibiotics into the food chain, recent extensions of prescribing responsibilities and developments towards improved surveillance and reduced antibiotic prescribing. A large gap remains between the scientific appreciation of the risks from antimicrobial resistance and effective means to measure it and thereby hopefully control it.

Effect of antibiotic prescribing on antibiotic resistance in individual children in primary care: prospective cohort study

OBJECTIVE

To assess the effect of community prescribing of an antibiotic for acute respiratory infection on the prevalence of antibiotic resistant bacteria in an individual child.

STUDY DESIGN

Observational cohort study with follow-up at two and 12 weeks.

SETTING

General practices in Oxfordshire.

PARTICIPANTS

119 children with acute respiratory tract infection, of whom 71 received a beta lactam antibiotic.

MAIN OUTCOME MEASURES

Antibiotic resistance was assessed by the geometric mean minimum inhibitory concentration (MIC) for ampicillin and presence of the ICEHin1056 resistance element in up to four isolates of Haemophilus species recovered from throat swabs at recruitment, two weeks, and 12 weeks.

RESULTS

Prescribing amoxicillin to a child in general practice more than triples the mean minimum inhibitory concentration for ampicillin (9.2 microg/ml v 2.7 microg/ml, P=0.005) and doubles the risk of isolation of Haemophilus isolates possessing homologues of ICEHin1056 (67% v 36%; relative risk 1.9, 95% confidence interval 1.2 to 2.9) two weeks later. Although this increase is transient (by 12 weeks ampicillin resistance had fallen close to baseline), it is in the context of recovery of the element from 35% of children with Haemophilus isolates at recruitment and from 83% (76% to 89%) at some point in the study.

CONCLUSION

The short term effect of amoxicillin prescribed in primary care is transitory in the individual child but sufficient to sustain a high level of antibiotic resistance in the population.

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.

Microbial pattern and antimicrobial resistance, a surgeon's perspective: retrospective study in surgical wards and seven intensive-care units in two university hospitals in Cairo, Egypt

OBJECTIVES

Significant morbidity and mortality in surgical practice is due to infection with resistant pathogens. Data from Egyptian hospitals may reflect a peculiar pattern.

METHODS

Retrospective study of antimicrobial susceptibility of 1,064 isolates from patients in surgical zones and intensive-care units (ICUs) in the largest 2 hospitals in Cairo in 2003.

RESULTS

The infection rate in surgical wards was 0.41%, mostly surgical site infections. Cardiothoracic wards showed higher rates (0.52%). In ICUs, the infection rate was 6.51%, the majority were respiratory. The highest resistance rate was shown by Staphylococcus aureus (23.8%), Pseudomonas (14.9%) and Escherichia coli (10.48%). Enterococci and Citrobacter had rates below 1%. Pseudomonas aeruginosa had the highest resistance rate with third-generation cephalosporins (Cef3) and the lowest with imipenem, while for Enterobacter and Klebsiella it was highest with Cef3 and lowest with imipenem. E. coli showed the highest rate with quinolone 2 and Cef3, but there was no resistance to imipenem. Acinetobacter demonstrated the highest resistance rate with quinolone 2 and the lowest with fourth-generation cephalosporins (Cef4), while for methicillin-resistant S. aureus it was 60%. All enterococci were sensitive to vancomycin.

CONCLUSION

The study provides meaningful data on a high antimicrobial resistance in Egypt. Failure of hospital hygiene and overuse of antibiotics are considered responsible.

Interventions to improve antibiotic prescribing practices in ambulatory care

BACKGROUND

The development of resistance to antibiotics by many important human pathogens has been linked to exposure to antibiotics over time. The misuse of antibiotics for viral infections (for which they are of no value) and the excessive use of broad spectrum antibiotics in place of narrower spectrum antibiotics have been well-documented throughout the world. Many studies have helped to elucidate the reasons physicians use antibiotics inappropriately.

OBJECTIVES

To systematically review the literature to estimate the effectiveness of professional interventions, alone or in combination, in improving the selection, dose and treatment duration of antibiotics prescribed by healthcare providers in the outpatient setting; and to evaluate the impact of these interventions on reducing the incidence of antimicrobial resistant pathogens.

SEARCH STRATEGY

We searched the Cochrane Effective Practice and Organisation of Care Group (EPOC) specialized register for studies relating to antibiotic prescribing and ambulatory care. Additional studies were obtained from the bibliographies of retrieved articles, the Scientific Citation Index and personal files.

SELECTION CRITERIA

We included all randomised and quasi-randomised controlled trials (RCT and QRCT), controlled before and after studies (CBA) and interrupted time series (ITS) studies of healthcare consumers or healthcare professionals who provide primary care in the outpatient setting. Interventions included any professional intervention, as defined by EPOC, or a patient-based intervention.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and assessed study quality.

MAIN RESULTS

Thirty-nine studies examined the effect of printed educational materials for physicians, audit and feedback, educational meetings, educational outreach visits, financial and healthcare system changes, physician reminders, patient-based interventions and multi-faceted interventions. These interventions addressed the overuse of antibiotics for viral infections, the choice of antibiotic for bacterial infections such as streptococcal pharyngitis and urinary tract infection, and the duration of use of antibiotics for conditions such as acute otitis media. Use of printed educational materials or audit and feedback alone resulted in no or only small changes in prescribing. The exception was a study documenting a sustained reduction in macrolide use in Finland following the publication of a warning against their use for group A streptococcal infections. Interactive educational meetings appeared to be more effective than didactic lectures. Educational outreach visits and physician reminders produced mixed results. Patient-based interventions, particularly the use of delayed prescriptions for infections for which antibiotics were not immediately indicated effectively reduced antibiotic use by patients and did not result in excess morbidity. Multi-faceted interventions combining physician, patient and public education in a variety of venues and formats were the most successful in reducing antibiotic prescribing for inappropriate indications. Only one of four studies demonstrated a sustained reduction in the incidence of antibiotic-resistant bacteria associated with the intervention.

AUTHORS' CONCLUSIONS

The effectiveness of an intervention on antibiotic prescribing depends to a large degree on the particular prescribing behaviour and the barriers to change in the particular community. No single intervention can be recommended for all behaviours in any setting. Multi-faceted interventions where educational interventions occur on many levels may be successfully applied to communities after addressing local barriers to change. These were the only interventions with effect sizes of sufficient magnitude to potentially reduce the incidence of antibiotic-resistant bacteria. Future research should focus on which elements of these interventions are the most effective. In addition, patient-based interventions and physician reminders show promise and innovative methods such as these deserve further study.

The resistance ratchet: theoretical implications of cyclic selection pressure

OBJECTIVES

To investigate the effects of cyclic antibiotic selection pressure on resistance in a simple mathematical model.

METHODS

The model assumed that resistance in microbial ecologies changes slowly with changing selection pressure, at a rate proportional to the difference between the current resistance level and the resistance level that would be in equilibrium with current selection pressure. The maximum rate of increase in resistance during periods of increasing selection was assumed to be greater than the maximum rate of decrease during decreased selection.

RESULTS

Under a simulated annual cyclic selection pressure variation of 40%, with maximum resistance rise and fall rates of 10 and 0.5%, respectively, resistance rose above the level expected from the mean selection pressure by small ratchet-like increments. Over 50 simulated years, resistance increased to 62%, rather than the 50% expected from the mean level of selection. Welsh community prescribing for a selection of antibiotics showed a seasonal cyclic variation of 13-45%.

CONCLUSIONS

The intuitive assumption that cyclic selective pressure would produce resistance levels commensurate with the mean selection pressure was contradicted; rather resistance drifted towards a level commensurate with maximum selection pressure. If the ratchet effect exists in reality, it may produce unexpected excess resistance, particularly in the community for antibiotics used in respiratory infection, where cycling is pronounced, or in ITU antibiotic rotation. It should be most pronounced for resistance systems with strong asymmetry between rates of adaptation under rising and falling selection pressure. Non-linear dynamic systems in physics and ecology are notorious for producing counter-intuitive effects; resistance epidemiology may be similar.

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.

Clinical items not helpful in differentiating viral from bacterial lower respiratory tract infections in general practice

OBJECTIVE

Incorrect and unnecessary antibiotic prescribing enhancing bacterial resistance rates might be reduced if viral and bacterial lower respiratory tract infections (LRTI) could be differentiated clinically. Whether this is possible is often doubted but has rarely been studied in general practice.

STUDY DESIGN AND SETTING

This was an observational cohort study in 15 general practice surgeries in the Netherlands.

RESULTS

Etiologic diagnoses were obtained in 112 of 234 patients with complete data (48%). Viral pathogens were found as often as bacterial pathogens. Haemophilus (para-) influenzae was most frequently found. None of the symptoms and signs correlated statistically significantly with viral or bacterial LRTI. Erythrocyte sedimentation rate >50 (odds ratio [OR] 2.3-3.3) and C-reactive protein (CRP) >20 (OR 2.1-4.6) were independent predictors for viral LRTI and bacterial LRTI when compared with microbiologically unexplained LRTI.

CONCLUSION

Extensive history-taking and physical examination did not provide items that predict viral or bacterial LRTI in adult patients in daily general practice. We could not confirm CRP to differentiate between viral and bacterial LRTI.

Finding a strategy: the case for co-operative research on resistance epidemiology

Progress on rational intervention to prevent increasing antibiotic resistance has been slow. We suggest that this is because the science of resistance epidemiology has received little attention, and that a systematic, co-operative investigation of this area might yield a relevant knowledge base, analogous to the basis for effective public health intervention in infectious disease given by infection epidemiology. The steps required to progress this approach in the UK are discussed, along with a summary of what is known and speculation on what might emerge.

Diagnosis of genital chlamydia in primary care: an explanation of reasons for variation in chlamydia testing

OBJECTIVES

To explore the reasons for the 40-fold variation in diagnostic testing for genital Chlamydia trachomatis by general practices.

METHODS

A qualitative study with focus groups. We randomly selected urban and rural high and low testing practices served by Bristol, Hereford, and Gloucester microbiology laboratories. Open questions were asked about the investigation of C trachomatis in men and women in different clinical contexts.

RESULTS

The high and low testing practices did not differ in their age/sex make-up or by deprivation indices. There were major differences between high and low chlamydia testing practices. Low testing practices knew very little about the epidemiology and presentation of genital chlamydia infection and did not consider it in their differential diagnosis of genitourinary symptoms until patients had consulted several times. Low testers were less aware that chlamydia was usually asymptomatic, thought it was an inner city problem, and had poor knowledge of how to take diagnostic specimens. High testing practices either had a general practitioner with an interest in sexual health or a practice nurse who had completed specialist training in family planning. High testing practices were more cognizant of the symptoms and signs of chlamydia and always considered it in their differential diagnosis of genitourinary symptoms, including patients attending family planning clinics.

CONCLUSIONS

Any programme to increase chlamydia testing in primary care must be accompanied by an education and awareness programme especially targeted at low testing practices. This will need to include information about the benefits of testing and who, when, and how to test.

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.

Contributions of symptoms, signs, erythrocyte sedimentation rate, and C-reactive protein to a diagnosis of pneumonia in acute lower respiratory tract infection

BACKGROUND

Diagnostic tests enabling general practitioners (GPs) to differentiate rapidly between pneumonia and other lower respiratory tract infections (LRTIs) are needed to prevent increase of bacterial resistance by unjustified antibiotic prescribing.

AIMS

To assess the diagnostic value of symptoms, signs, erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) for pneumonia; to derive a prediction rule for the presence of pneumonia; and to identify a low-risk group of patients who do not require antibiotic treatment.

DESIGN OF STUDY

Cross-sectional.

SETTING

Fifteen GP surgeries in the southern part of The Netherlands.

METHOD

Twenty-five GPs recorded clinical information and diagnosis in 246 adult patients presenting with LRTI. Venous blood samples for CRP and ESR were taken and chest radiographs (reference standard) were made. Odds ratios, describing the relationships between discrete diagnostic variables and reference standard (pneumonia or no pneumonia) were calculated. Receiver operating characteristic analysis of ESR, CRP, and final models for pneumonia was performed. Prediction rules for pneumonia were derived from multiple logistic regression analysis.

RESULTS

Dry cough, diarrhoea, and a recorded temperature of > or = 38 degrees C were independent and statistically significant predictors of pneumonia, whereas abnormal pulmonary auscultation and clinical diagnosis of pneumonia by the GPs were not. ESR and CRP had higher diagnostic odds ratios than any of the symptoms and signs. Adding CRP to the final 'symptoms and signs' model significantly increased the probability of correct diagnosis. Applying a prediction rule for low-risk patients, including a CRP of < 20, 80 of the 193 antibiotic prescriptions could have been prevented with a maximum risk of 2.5% of missing a pneumonia case.

CONCLUSION

Most symptoms and signs traditionally associated with pneumonia are not predictive of pneumonia in general practice. The prediction rule for low-risk patients presented here, including a CRP of < 20, can considerably reduce unjustified antibiotic prescribing.

Why we need to know whether prophylactic antibiotics can reduce measles-related morbidity

In some parts of the world, measles vaccination has resulted in very substantial reductions in measles-related morbidity and mortality. Even so, it has been estimated that 30 million people still contract the disease every year, that nearly 1 million of these die, and that measles-related deaths account for about 10% of all deaths in children under the age of 5 in developing countries. Existing evidence from controlled trials suggests that antibiotic prophylaxis in measles can result in important reductions in measles-related morbidity, and, at a World Health Organization meeting convened in 1993 to decide on research priorities for the treatment of measles, highest priority was accorded to additional controlled trials of prophylactic antibiotics. As controlled trials of vitamin A in measles have made clear, such trials are feasible. Continued acquiescence in uncertainties about the effects of prophylactic antibiotics in a disease that continues to afflict so many children worldwide is unacceptable.