Antibiotic treatment of gastroenteritis in primary care.

Background: Gastroenteritis (GE) is a frequent reason for consultating a general practitioner. Yet little is known about antibiotic prescribing in primary care patients with GE. In this study, we quantified empirical and targeted antibiotic treatment of GE, compliance with recommendations from primary care clinical practice guidelines (CPGs) and the degree of antimicrobial resistance in patients receiving diagnostic faeces testing (DFT). Methods: We performed a cohort study using routine care data of 160 general practitioners, including electronic patient records from 2013 to 2014. GE episodes were extracted and linked to microbiological laboratory records to retrieve results of DFT. For each episode, data on patient characteristics, DFT results including antimicrobial resistance testing, and antibiotic prescriptions were collected. Results: We identified 13217 GE episodes. Antibiotic treatment was prescribed in 1163 (8.8%) episodes, most frequently with metronidazole (n = 646, 4.9%), azithromycin (n = 254, 1.9%) or ciprofloxacin (n = 184, 1.4%). Treatment was empirical for 641 (5%) GE episodes, of which 30% (n = 191) followed the CPG-recommended antibiotic choice. Targeted treatment following DFT results was prescribed for 537 GE episodes (4%), of which 99% (n = 529) followed CPG recommendations. Non-susceptibility to first- or second-choice antibiotics was demonstrated in three Salmonella isolates (9%-13% of all isolates) and one Campylobacter isolate (1%). Conclusions: Antibiotic treatment of GE in primary care is relatively infrequent, with 1 in 11 episodes treated. Empirical treatment was more frequent compared with targeted treatment and mostly with non-CPG-recommended antibiotics. However, treatment based upon DFT results followed CPG recommendations.

The added value of C-reactive protein measurement in diagnosing pneumonia in primary care: a meta-analysis of individual patient data.

BACKGROUND: C-reactive protein (CRP) is increasingly being included in the diagnostic work-up for community-acquired pneumonia in primary care. Its added diagnostic value beyond signs and symptoms, however, remains unclear. We conducted a meta-analysis of individual patient data to quantify the added value of CRP measurement. METHODS: We included studies of the diagnostic accuracy of CRP in adult outpatients with suspected lower respiratory tract infection. We contacted authors of eligible studies for inclusion of data and for additional data as needed. The value of adding CRP measurement to a basic signs-and-symptoms prediction model was assessed. Outcome measures were improvement in discrimination between patients with and without pneumonia in primary care and improvement in risk classification, both within the individual studies and across studies. RESULTS: Authors of 8 eligible studies (n = 5308) provided their data sets. In all of the data sets, discrimination between patients with and without pneumonia improved after CRP measurement was added to the prediction model (extended model), with a mean improvement in the area under the curve of 0.075 (range 0.02-0.18). In a hypothetical cohort of 1000 patients, the proportion of patients without pneumonia correctly classified at low risk increased from 28% to 36% in the extended model, and the proportion with pneumonia correctly classified at high risk increased from 63% to 70%. The number of patients with pneumonia classified at low risk did not change (n = 4). Overall, the proportion of patients assigned to the intermediate-risk category decreased from 56% to 51%. INTERPRETATION: Adding CRP measurement to the diagnostic work-up for suspected pneumonia in primary care improved the discrimination and risk classification of patients. However, it still left a substantial group of patients classified at intermediate risk, in which clinical decision-making remains challenging.

Guideline adherence for diagnostic faeces testing in primary care patients with gastroenteritis.

Background: Gastroenteritis (GE) is a common reason for primary care consultation. Dutch clinical practice guidelines (CPG) recommend diagnostic faeces testing (DFT) only in primary care patients with severe illness, comprised immunity or increased transmission risk. For its superior accuracy, shorter turnaround time and ease of use, polymerase chain reaction (PCR)-based DFT has largely replaced conventional techniques. It is unknown whether this changed CPG adherence. Objective: To quantify the effect of PCR introduction on adherence to CPG indications for DFT in primary care patients with GE. Methods: We performed a cohort study using routine care data of 225 GPs. Episodes of GE where DFT was performed were extracted from electronic patient records. Presenting symptoms were identified and adherence to CPG indications for DFT assessed in two randomly drawn samples of each 500 patients, one from the period before PCR introduction (2010-11) and one after (2013). The association between PCR introduction and adherence was estimated using multivariable regression analysis. Results: In 88% of all episodes relevant presenting symptoms were reported, most often 'frequent watery stool' (58%) and 'illness duration >10 days' (40%). DFT was performed in 15% of episodes before PCR introduction and in 18% after. Overall, in 17% the DFT request was considered adherent to the CPG, 16% before PCR introduction and 18% after (adjusted OR 1.2, 95% CI 0.9-1.7). Conclusion: Overall adherence to CPG indications when requesting DFT in primary care patient with GE was 17%. Implementation of PCR-based DFT was not associated with a change in CPG adherence.

Design of the PROUD study: PCR faeces testing in outpatients with diarrhoea.

BACKGROUND: Infectious intestinal disease (IID) is an important cause of morbidity in developed countries and a frequent reason for general practitioner (GP) consultation. In recent years polymerase chain reaction (PCR) based techniques have gradually replaced conventional enteropathogen detection techniques like microscopy and culture in primary care patients suspected of IID. PCR features testing of multiple enteropathogens in a single faecal sample with shorter turnaround times and greater sensitivity compared to conventional techniques. However, the associated costs and benefits have not been quantified. Furthermore, primary care incidence and prevalence estimates of enteropathogens associated with IID are sparsely available and predominantly based on conventional techniques. The PROUD-study (PCR diagnostics in Outpatients with Diarrhoea) determines: 1) health (care) effects and 2) cost-effectiveness of PCR introduction in primary care patients suspected of IID; 3) occurrence of major enteropathogens in primary care patients suspected of IID. METHODS: A before-after cohort study will be performed of patients with suspected IID consulting a GP in the Utrecht General Practitioner Network (UGPN), covering the before period (2010-2011) with conventional testing and the after period (2013-2014) with PCR testing. Prospective study data on patient characteristics and primary outcome measures (i.e. healthcare use and disease outcome) will be collected from electronic patient and laboratory records in 2015 and 2016. The effect of PCR introduction is investigated by comparing the primary outcome measures and their associated healthcare costs between the conventional period and the PCR period, and is followed by a cost-effectiveness analysis. To determine the occurrence of enteropathogens associated with IID in primary care, routine care faeces samples from the year 2014 will be screened using PCR. DISCUSSION: The PROUD-study will quantify the costs and effects of the introduction of PCR techniques for enteropathogens in primary care patients suspected of IID and generate up-to-date and sensitive estimates of enteropathogen occurrence among primary care patients.

Analysis of recruitment in a pragmatic observational study on C-reactive protein point-of-care testing in primary care.

INTRODUCTION: Failure to recruit all eligible study patients can lead to biased results. Little is known on selective patient recruitment in studies on implementation of diagnostic devices. OBJECTIVES: The aim of this observational study was to measure recruitment of patients in an implementation study in primary care on use of point-of-care (POC) C-reactive protein (CRP) and to evaluate recruitment bias and its impact on the study endpoint. METHODS: In a cross-sectional observational study on POC CRP implementation and related antibiotics prescribing, we compared included patients with all eligible patients to assess the representativeness of the included subjects. Eligible patients were adults presenting with acute cough in primary care between March and September 2012. The frequency of POC CRP testing and the proportion of prescribed antibiotics were compared between recruited and non-recruited patients. As measure of bias, odds ratios (ORs) with accompanying 95% confidence intervals (CIs) for the association between CRP level (<20 mg/l or not) and antibiotic prescribing were computed. RESULTS: Of all 1473 eligible patients 348 (24%) were recruited. In recruited patients, POC CRP tests were conducted and antibiotics prescribed more frequently as compared to non-recruited patients (81% versus 6% and 44% versus 29%, respectively). The ORs were 18.2 (95%CI: 9.6-34.3), 30.5 (95%CI: 13.2-70.3) and 3.8 (95%CI: 0.9-14.8) respectively in all eligible patients, the recruited and the non-recruited patients. CONCLUSION: Selective recruitment resulted in an overestimation of POC CRP test use and antibiotic prescribing.

External Validation of Prediction Models for Pneumonia in Primary Care Patients with Lower Respiratory Tract Infection: An Individual Patient Data Meta-Analysis.

BACKGROUND: Pneumonia remains difficult to diagnose in primary care. Prediction models based on signs and symptoms (S&S) serve to minimize the diagnostic uncertainty. External validation of these models is essential before implementation into routine practice. In this study all published S&S models for prediction of pneumonia in primary care were externally validated in the individual patient data (IPD) of previously performed diagnostic studies. METHODS AND FINDINGS: S&S models for diagnosing pneumonia in adults presenting to primary care with lower respiratory tract infection and IPD for validation were identified through a systematical search. Six prediction models and IPD of eight diagnostic studies (N total = 5308, prevalence pneumonia 12%) were included. Models were assessed on discrimination and calibration. Discrimination was measured using the pooled Area Under the Curve (AUC) and delta AUC, representing the performance of an individual model relative to the average dataset performance. Prediction models by van Vugt et al. and Heckerling et al. demonstrated the highest pooled AUC of 0.79 (95% CI 0.74-0.85) and 0.72 (0.68-0.76), respectively. Other models by Diehr et al., Singal et al., Melbye et al., and Hopstaken et al. demonstrated pooled AUCs of 0.65 (0.61-0.68), 0.64 (0.61-0.67), 0.56 (0.49-0.63) and 0.53 (0.5-0.56), respectively. A similar ranking was present based on the delta AUCs of the models. Calibration demonstrated close agreement of observed and predicted probabilities in the models by van Vugt et al. and Singal et al., other models lacked such correspondence. The absence of predictors in the IPD on dataset level hampered a systematical comparison of model performance and could be a limitation to the study. CONCLUSIONS: The model by van Vugt et al. demonstrated the highest discriminative accuracy coupled with reasonable to good calibration across the IPD of different study populations. This model is therefore the main candidate for primary care use.

Efficacy of contingency management for cocaine dependence treatment: a review of the evidence.

Cocaine dependence causes serious individual and social harm and a considerable proportion of substance related treatment capacity is devoted to cocaine dependent persons. In the absence of approved pharmacotherapies, other treatments for cocaine dependence should be explored. In this review, the efficacy of Contingency Management (CM), a promising behavior therapy using operant conditioning, is evaluated for the treatment of cocaine dependence. A systematic evaluation of 19 studies with a total of 1,664 patients showed that CM - in combination with standard cognitive behavioral or other psychological interventions - (1) increases cocaine abstinence, (2) improves treatment retention during and after group-based or individual psychological treatment, (3) is of benefit in pharmacotherapy trials, and (4) that CM may act synergistically with pharmacotherapy. This suggests that CM is a promising add-on intervention for cocaine dependence treatment. Therefore, it is advocated to include CM in standard treatment programs for cocaine dependence and future pharmacotherapy research. Future larger studies are deemed necessary to replicate these promising results, now often lacking statistical significance.