Theo J M Verheij

University Medical Center Utrecht, Utrecht, Utrecht, Netherlands

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Publications (215)962.74 Total impact

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    ABSTRACT: Evidence shows a high rate of unnecessary antibiotic prescriptions in primary care in Europe and the United States. Given the costs of widespread use and associated antibiotic resistance, reducing inappropriate use is a public health priority.
    Journal of general internal medicine. 11/2014;
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    ABSTRACT: To explore perceptions of safety culture in nine different types of primary care professions and to study possible differences.
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    ABSTRACT: Rhinovirus infections occur frequently throughout life and have been reported in about one-third of asymptomatic cases. The clinical significance of sequential rhinovirus infections remains unclear. To determine the incidence and clinical relevance of sequential rhinovirus detections, nasopharyngeal samples from 2485 adults with acute cough/lower respiratory illness were analysed. Patients were enrolled prospectively by general practitioners from 12 European Union countries during three consecutive years (2007-2010). Nasopharyngeal samples were collected at the initial general practitioner consultation and 28 days thereafter and symptom scores were recorded by patients over that period. Rhinovirus RNA was detected in 444 (18%) out of 2485 visit one samples and in 110 (4.4%) out of 2485 visit two respiratory samples. 21 (5%) of the 444 patients had both samples positive for rhinovirus. Genotyping of both virus detections was successful for 17 (81%) out of 21 of these patients. Prolonged rhinovirus shedding occurred in six (35%) out of 21 and re-infection with a different rhinovirus in 11 (65%) out of 21. Rhinovirus re-infections were significantly associated with chronic obstructive pulmonary disease (p=0.04) and asthma (p=0.02) and appeared to be more severe than prolonged infections. Our findings indicate that in immunocompetent adults rhinovirus re-infections are more common than prolonged infections, and chronic airway comorbidities might predispose to more frequent rhinovirus re-infections.
    The European respiratory journal. 07/2014; 44(1):169-77.
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    ABSTRACT: Canuti and Martin Deijs have contributed equally to this work. Previously unknown or unexpected pathogens may be responsible for that proportion of respiratory diseases in which a causative agent cannot be identified. The application of broad-spectrum, sequence independent virus discovery techniques may be useful to reduce this proportion and widen our knowledge about respiratory pathogens. Thanks to the availability of high-throughput sequencing (HTS) technology, it became today possible to detect viruses which are present at a very low load, but the clinical relevance of those viruses must be investigated. In this study we used VIDISCA-454, a restriction enzyme based virus discovery method that utilizes Roche 454 HTS system, on a nasal swab collected from a subject with respiratory complaints. A γ-papillomavirus was detected (complete genome: 7142 bp) and its role in disease was investigated. Respiratory samples collected both during the acute phase of the illness and 2 weeks after full recovery contained the virus. The patient presented antibodies directed against the virus but there was no difference between IgG levels in blood samples collected during the acute phase and 2 weeks after full recovery. We therefore concluded that the detected γ-papillomavirus is unlikely to be the causative agent of the respiratory complaints and its presence in the nose of the patient is not related to the disease. Although HTS based virus discovery techniques proved their great potential as a tool to clarify the etiology of some infectious diseases, the obtained information must be subjected to cautious interpretations. This study underlines the crucial importance of performing careful investigations on viruses identified when applying sensitive virus discovery techniques, since the mere identification of a virus and its presence in a clinical sample are not satisfactory proofs to establish a causative link with a disease.
    Frontiers in Microbiology 07/2014; 5:374. · 3.90 Impact Factor
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    ABSTRACT: A positive patient safety culture is considered a main condition for patient safety. Several initiatives have been taken with the intention to improve this culture in healthcare. Because these were mainly implemented in hospitalized care settings not much is known about ameliorating patient safety culture in general practice. Therefore, we aimed at examining the effect of two patient safety culture interventions in general practice. We conducted a cluster randomized three armed trial, one control group and two intervention groups, in thirty general practices in the Netherlands. The interventions consisted of a Dutch patient safety culture questionnaire solely, or this questionnaire combined with a workshop on practice location. The workshop was based on MaPSaF and processed the practice results of theculture questionnaire. It comprised theory and discussion with the objective to draw a practice specific action plan. After randomisation 10 practices served as controls, 10 practices received the safety culture questionnaire as intervention, and 10 had the combination of the questionnaire and the workshop. All practices were asked to fill out a practice information form before the intervention and one year hereafter. In this form general safety and quality issues were addressed such as whether the practice had a formal incident reporting procedure, the number of incident reports and whether they were analysed; whether there was a complaint procedure and number of registered complaints; whether there were staff meetings and if patient safety (culture) were part of these; whether training was followed in the field of patient safety and whether a safety management system or policy was present. Improvement in patient safety culture was operationalized as an increase in reported number of incident as a primary outcome measure. At follow-up, we also asked all staff of all practices, including the controls, to complete the safety culture questionnaire. In addition, to be able to evaluate the process of patient safety improvements we performed semi-structured interviews. Thirty practices completed the pre practice information form. During the intervention period two practices in the 'combination' group dropped out. For this, we randomly moved one of the control practices to this intervention group. Up until now, 27 practices filled out this questionnaire post intervention. The SCOPE questionnaire is completed by 171 respondents distributed over the 28 practices with a range of 1 to 13. We conducted 48 interviews with respectively 24 physicians, 21 medical assistants and 3 practice nurses. Data cleaning and analysis about to start and will be finished by the end of 2013. this study is one of the first attempting to at shed light on the effectiveness of patient safety culture improvement interventions in general practice. With collecting both quantitative and qualitative data, not only the effect of the intervention is examined but also potential underlying grounds for the results in the practices can be clarified. These findings will contribute to our knowledge about patient safety improvements in general practice and may enhance future interventions. None.
    BMJ quality & safety 04/2014; 23(4):350. · 2.39 Impact Factor
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    ABSTRACT: Patient safety culture, described as shared values, attitudes and behavior of staff in a health-care organization, gained attention as a subject of study as it is believed to be related to the impact of patient safety improvements. However, in primary care, it is yet unknown, which effect interventions have on the safety culture. To review literature on the use of interventions that effect patient safety culture in primary care. Searches were performed in PubMed, EMBASE, CINAHL, and PsychINFO on March 4, 2013. Terms defining safety culture were combined with terms identifying intervention and terms indicating primary care. Inclusion followed if the intervention effected patient safety culture, and effect measures were reported. The search yielded 214 articles from which two were eligible for inclusion. Both studies were heterogeneous in their interventions and outcome; we present a qualitative summary. One study described the implementation of an electronic medical record system in general practices as part of patient safety improvements. The other study facilitated 2 workshops for general practices, one on risk management and another on significant event audit. Results showed signs of improvement, but the level of evidence was low because of the design and methodological problems. These studies in general practice provide a first understanding of improvement strategies and their effect in primary care. As the level of evidence was low, no clear preference can be determined. Further research is needed to help practices make an informed choice for an intervention.
    Journal of Patient Safety 03/2014;
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    ABSTRACT: Countries generally present their overall use of antibiotics as an indicator of antibiotic prescribing quality. Additional insight is urgently needed for targeted improvement recommendations: first, data on specific clinical indications for which antibiotics are used, and second, on distinguishing whether changes in patient consultation or changes in physician prescribing drive changing antibiotic use for particular indications. The aim of this study was to describe the antibiotic management of infectious diseases in the clinical context, by analysing prescribing by physicians and patient consultation incidences per indication over time. A database with all contact data for infectious diseases from 45 primary care practices in the Netherlands (2007-10) was used. Consultation incidences, prescribing rates and choice of antibiotic were analysed per International Classification of Primary Care (ICPC) chapter and relevant ICPC codes. Antibiotics were prescribed in ∼25% of infectious disease episodes, mainly respiratory infections, urinary infections and ear and skin infections. Overall, this resulted in 300 prescribed courses of antibiotics per 1000 patient-years. Given a stable prescription rate, a 19% increase in the number of consultations explained the increased antibiotic prescribing for urinary tract infections. Given a stable consultation incidence, an 8% reduction in prescribing rate explained the decreased antibiotic prescribing for respiratory tract infections. Macrolides were predominantly prescribed for respiratory disease (∼66%), amoxicillin/clavulanate for respiratory disease (∼42%) and urinary illness (∼25%), and fluoroquinolones for urinary and genital indications. Insight into the reasons for the decreased prescribing for respiratory tract infections and the increased prescribing for urinary tract infections was provided by a detailed analysis of incidences and prescribing rates. For respiratory disease, the second- and third-choice antibiotics were overused. Complete data on infectious disease management, with respect to patient and physician behaviour, are crucial for understanding changes in antibiotic use, and in defining strategies to reduce inappropriate antibiotic use.
    Journal of Antimicrobial Chemotherapy 02/2014; · 5.34 Impact Factor
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    ABSTRACT: For a better understanding of the maintenance of immune mechanisms to Bordetella pertussis (Bp) in relation to age, we investigated the dynamic range of specific B cell responses in various age-groups at different time points after a laboratory confirmed pertussis infection. Blood samples were obtained in a Dutch cross sectional observational study from symptomatic pertussis cases. Lymphocyte subpopulations were phenotyped by flowcytometry before and after culture. Memory B (Bmem) cells were differentiated into IgG antibody secreting cells (ASC) by polyclonal stimulation and detected by an ELISPOT assay specific for pertussis antigens pertussis toxin (Ptx), filamentous haemagglutinin (FHA) and pertactin (Prn). Bp antigen specific IgG concentrations in plasma were determined using multiplex technology. The majority of subjects having experienced a clinical pertussis episode demonstrated high levels of both Bp specific IgG and Bmem cell levels within the first 6 weeks after diagnosis. Significantly lower levels were observed thereafter. Waning of cellular and humoral immunity to maintenance levels occurred within 9 months after antigen encounter. Age was found to determine the maximum but not base-line frequencies of Bmem cell populations; higher levels of Bmem cells specific for Ptx and FHA were reached in adults and (pre-) elderly compared to under-fours and schoolchildren in the first 6 weeks after Bp exposure, whereas not in later phases. This age effect was less obvious for specific IgG levels. Nonetheless, subjects' levels of specific Bmem cells and specific IgG were weakly correlated. This is the first study to show that both age and closeness to last Bp encounter impacts the size of Bp specific Bmem cell and plasma IgG levels.
    PLoS ONE 01/2014; 9(1):e85227. · 3.53 Impact Factor
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    ABSTRACT: General public views and expectations around the use of antibiotics can influence general practitioners' antibiotic prescribing decisions. We set out to describe the knowledge, attitudes and beliefs about the use of antibiotics for respiratory tract infections in adults in Poland, and explore differences according to where people live in an urban-rural continuum.
    PLoS ONE 01/2014; 9(10):e109248. · 3.53 Impact Factor
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    ABSTRACT: Background:In acute cough patients, impaired lung function as present in chronic lung conditions like asthma and chronic obstructive pulmonary disease (COPD) are often thought to negatively influence course of disease, but clear evidence is lacking.Aims:To investigate the influence of lung function abnormalities on course of disease and response to antibiotic therapy in primary care patients with acute cough.Methods:A total of 3,104 patients with acute cough (⩽28 days) were included in a prospective observational study with a within-nested trial, of which 2,427 underwent spirometry 28-35 days after inclusion. Influence of the lung function abnormalities fixed obstruction (forced expiratory volume in 1 s (FEV1)/forced vital capacity (FVC) ratio <0.7) and bronchodilator responsiveness (FEV1 increase of ⩾12% or 200 ml after 400 μg salbutamol) on symptom severity, duration and worsening were evaluated using uni- and multivariable regression models. Antibiotic use was defined as the reported use of antibiotics ⩾5 days in the first week. Interaction terms were calculated to investigate modifying effects of lung function on antibiotic effect.Results:The only significant association was the effect of severe airway obstruction on symptom severity on days 2-4 (difference=0.31, 95% confidence interval (CI)=0.03-0.60, P=0.03). No evidence of a differential effect of lung function on the effect of antibiotics was found. Prior use of inhaled steroids was associated with a 30% slower resolution of symptoms rated 'moderately bad' or worse (hazard ratio=0.75, 95% CI=0.63-0.90, P=0.00).Conclusions:In adult patients with acute cough, lung function abnormalities were neither significantly associated with course of disease nor did they modify the effect of antibiotics.
    NPJ primary care respiratory medicine. 01/2014; 24:14067.
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    ABSTRACT: Despite stable overall antibiotic use between 2007 and 2011 in The Netherlands, use of nitrofurantoin and trimethoprim increased by 32%. The background of this increased antibiotic use against uropathogens is unknown. To determine whether increased use of urinary tract infection antibiotics is caused by changes in patients' consultation or physicians' prescribing behaviour and to investigate attitudes and opinions of women with respect to cystitis management and antibiotics. Consultation and prescribing for International Classification of Primary Care (ICPC) codes U01 (dysuria), U02 (frequency), U05 (other urination problems), U70 (pyelonephritis) and U71 (cystitis) were determined from 2007 to 2010, using routinely collected primary health care data. Separately, behaviour of women with respect to managing cystitis, consultation and opinions towards (delayed) antibiotic treatment were studied using questionnaires in 2012. Consultation for U02 and U71 significantly increased from 93 to 114/1000 patient-years from 2007 to 2010; proportion of episodes in which an antibiotic was prescribed remained constant. Questionnaires revealed that urination problems and pain were dominant complaints of cystitis; pain medication, however, was not adequately used. One-third of women directly consult upon first symptoms, whereas the majority awaits an average of 4 days. Sixty-six per cent of women report to be willing to postpone antibiotic use. Increased use of urinary tract infection antibiotics may be caused by increased consultation for cystitis in primary care. Future research should focus on the outcomes of adequate pain medication, enhanced diagnostic procedures and of delaying antibiotic use in cystitis management.
    Family Practice 12/2013; · 1.83 Impact Factor
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    ABSTRACT: Clinician-parent interaction and health system influences on parental acceptance of prescribing decisions for children with respiratory tract infections (RTIs) may be important determinants of antibiotic use. To achieve a deeper understanding of parents' acceptance, or otherwise, of clinicians' antibiotic prescribing decisions for children with RTIs. Qualitative interviews with parents of child patients who had recently consulted in primary care with a RTI in four European countries, with a five-stage analytic framework approach (familiarization, developing a thematic framework from interview questions and emerging themes, indexing, charting and interpretation). Fifty of 63 parents accepted clinicians' management decisions, irrespective of antibiotic prescription. There were no notable differences between networks. Parents ascribed their acceptance to a trusting and open clinician-patient relationship, enhanced through continuity of care, in which parents felt able to express their views. There was a lack of congruence about antibiotics between parents and clinicians in 13 instances, mostly when parents disagreed about clinicians' decision to prescribe (10 accounts) rather than objecting to withholding antibiotics (three accounts). All but one parent adhered to the prescribing decision, although some modified how the antibiotic was administered. Parents from contrasting countries indicated that continuity of care, open communication in consultations and clinician-patient trust was important in acceptance of management of RTI in their children and in motivating adherence. Interventions to promote appropriate antibiotic use in children should consider a focus on eliciting parents' perspectives and promoting and building on continuity of care within a trusting clinician-patient relationship.
    Family Practice 10/2013; · 1.83 Impact Factor
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    ABSTRACT: Background. Point-of-care (POC) C-reactive protein (CRP) testing is increasingly used in primary care to assist general practitioners (GPs) in the diagnostic workup for various complaints. The present study compares analytical performance, agreement and user-friendliness of five of these POC CRP tests. Methods. The following five POC CRP tests were evaluated: Afinion and NycoCard Reader II (both Alere), Eurolyser Smart 700/340 (Eurolyser), QuikRead go and QuikRead 101 (both Orion Diagnostica). Results were compared with those of a standard immunoturbidimetric method performed on a routine analyzer (Olympus AU 2700, Beckman Coulter). Analytical performance and agreement with the laboratory standard for the five different POC tests were analyzed. Subsequently, user-friendliness of the POC tests was assessed. Results. Within-day CVs varied from 2.6% (QuikRead go) to 19.4% (Eurolyser Smart 700/340) for low CRP values (< 20 mg/L), and 1.1% (QuikRead go) to 17.5% (Eurolyser Smart 700/340) for high values (> 100 mg/L). Between-day CVs varied from 4.6% (Afinion) to 30.5% (Eurolyser Smart 700/340) for low values and 4.0% (QuikRead go) to 18.0% (Eurolyser Smart 700/340) for high values. With high CRP values (> 100 mg/L) agreement with the laboratory standard systematically decreased for all POC tests. Regarding user-friendliness Afinion and Eurolyser Smart 700/340 were judged easiest to operate. Conclusions. Analytical performance, agreement, and user-friendliness of the POC CRP tests varied considerably, yet overall four devices showed adequate analytical performance and agreement.
    Scandinavian journal of clinical and laboratory investigation 10/2013; · 1.38 Impact Factor
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    ABSTRACT: Background High-volume prescribing of antibiotics in primary care is a major driver of antibiotic resistance. Education of physicians and patients can lower prescribing levels, but it frequently relies on highly trained staff. We assessed whether internet-based training methods could alter prescribing practices in multiple health-care systems. Methods After a baseline audit in October to December, 2010, primary-care practices in six European countries were cluster randomised to usual care, training in the use of a C-reactive protein (CRP) test at point of care, in enhanced communication skills, or in both CRP and enhanced communication. Patients were recruited from February to May, 2011. This trial is registered, number ISRCTN99871214. Results The baseline audit, done in 259 practices, provided data for 6771 patients with lower-respiratory-tract infections (3742 [55·3%]) and upper-respiratory-tract infections (1416 [20·9%]), of whom 5355 (79·1%) were prescribed antibiotics. After randomisation, 246 practices were included and 4264 patients were recruited. The antibiotic prescribing rate was lower with CRP training than without (33% vs 48%, adjusted risk ratio 0·54, 95% CI 0·42—0·69) and with enhanced-communication training than without (36% vs 45%, 0·69, 0·54—0·87). The combined intervention was associated with the greatest reduction in prescribing rate (CRP risk ratio 0·53, 95% CI 0·36—0·74, p<0·0001; enhanced communication 0·68, 0·50—0·89, p=0·003; combined 0·38, 0·25—0·55, p<0·0001). Interpretation Internet training achieved important reductions in antibiotic prescribing for respiratory-tract infections across language and cultural boundaries. Funding European Commission Framework Programme 6, National Institute for Health Research, Research Foundation Flanders.
    The Lancet 10/2013; 382(9899):1175-82. · 39.21 Impact Factor
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    The Lancet 10/2013; 382(9899):1175-82. · 39.21 Impact Factor
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    ABSTRACT: Interferon-inducible transmembrane proteins 1, 2 and 3 (IFITM1,2 and 3) are viral restriction factors that mediate cellular resistance to several viruses. We have genotyped a possible splice-site altering SNP (rs12252) in the IFITM3 gene in 34 H1N1 influenza cases with severe pneumonia and over 5000 individuals comprising cases of community-acquired mild lower respiratory tract infection and matched controls of Caucasian ancestry. We found evidence of an association between rs12252 rare allele homozygotes and susceptibility to mild influenza (in patients attending primary care), but could not confirm a previously reported association between this SNP and susceptibility to severe H1N1 infection.
    The Journal of Infectious Diseases 08/2013; · 5.85 Impact Factor
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    ABSTRACT: BACKGROUND: The diagnostic value of C-reactive protein (CRP) level for pneumonia in children is unknown. As a first step in the assessment of the value of CRP, a diagnostic study was performed in children at an emergency department (ED). METHODS: In this cross-sectional study, data were retrospectively collected from children presenting with suspected pneumonia at the ED of Antonius Hospital Nieuwegein in The Netherlands between January 2007 and January 2012. Diagnostic outcome was pneumonia yes/no according to independent radiologist. (Un)adjusted association between CRP level and pneumonia and diagnostic value of CRP were calculated. RESULTS: Of 687 presenting children, 286 underwent both CRP measurement and chest radiography. 148 had pneumonia (52%). The proportion of pneumonia increased with CRP level. Negative predictive values declined, but positive predictive values increased with higher CRP thresholds. Univariable odds ratio for the association between CRP level and pneumonia was 1.2 (95% CI 1.11-1.21) per 10 mg/L increase. After adjustment for baseline characteristics CRP level remained associated with pneumonia. CONCLUSIONS: CRP level has independent diagnostic value for pneumonia in children presenting at the ED with suspected pneumonia, but low levels do not exclude pneumonia in this setting. These results prompt evaluation of CRP in primary care children with LRTI.
    Respiratory medicine 05/2013; · 2.33 Impact Factor
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    ABSTRACT: BACKGROUND: An open, constructive safety culture is key in healthcare since it is seen as a main condition for patient safety. Studies have examined culture improvement strategies in hospitals. In primary care, however, not much is known about effective strategies to improve the safety culture yet. The purpose of this study is to examine the effect of two patient safety culture interventions: a patient safety culture questionnaire solely, the SCOPE, or the SCOPE questionnaire combined with a patient safety workshop. The purpose of this paper is to describe the rationale and design of this trial. METHODS/DESIGN: The SCOPE Intervention Study is a cluster randomized, three-armed controlled trial, that will be conducted in 30 general practices in the Netherlands. Ten practices in the first intervention arm will complete the SCOPE questionnaire and are expected to draw and implement their own improvement initiatives based on a computerised feedback report. In the second intervention arm, staff of the ten practices also will be asked to complete the SCOPE questionnaire and in addition will be given a complementary workshop. This workshop is theoretical and interactive, educating staff and facilitating discussion, leading to a practice specific action plan for patient safety improvement. The results of the SCOPE questionnaire are incorporated in the workshop. The ten practices in the control arm continue care as usual. Baseline and follow-up measurements will be conducted with an implementation period of one year. The primary outcome will include the number of incidents reported and secondary several quality and safety indicators and the patient safety culture. Moreover, interviews will be conducted at follow-up to evaluate the implementation process of the intervention. DISCUSSION: Results of this study will give insight in the effect of administering a culture questionnaire or the questionnaire with a complementary workshop. This knowledge will aid implementation of patient safety tools and future research. Attention has been given to the strengths and limitations of the study. TRIAL REGISTRATION: Netherlands Trial Register: NTR3277
    BMC.Fam.Pract. 01/2013; 14:127-.
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    ABSTRACT: Pertussis is still occurring in highly vaccinated populations, affecting individuals of all ages. Long-lived Th1 CD4(+) T cells are essential for protective immunity against pertussis. For better understanding of the limited immunological memory to Bordetella pertussis, we used a panel of Pertactin and Pertussis toxin specific peptides to interrogate CD4(+) T cell responses at the epitope level in a unique cohort of symptomatic pertussis patients of different ages, at various time intervals after infection. Our study showed that pertussis epitope-specific T cell responses contained Th1 and Th2 components irrespective of the epitope studied, time after infection, or age. In contrast, the breadth of the pertussis-directed CD4(+) T cell response seemed dependent on age and closeness to infection. Multi-epitope specificity long-term after infection was lost in older age groups. Detailed knowledge on pertussis specific immune mechanisms and their insufficiencies is important for understanding resurgence of pertussis in highly vaccinated populations.
    PLoS ONE 01/2013; 8(12):e83583. · 3.53 Impact Factor
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    ABSTRACT: To quantify the diagnostic accuracy of selected inflammatory markers in addition to symptoms and signs for predicting pneumonia and to derive a diagnostic tool. Diagnostic study performed between 2007 and 2010. Participants had their history taken, underwent physical examination and measurement of C reactive protein (CRP) and procalcitonin in venous blood on the day they first consulted, and underwent chest radiography within seven days. Primary care centres in 12 European countries. Adults presenting with acute cough. Pneumonia as determined by radiologists, who were blind to all other information when they judged chest radiographs. Of 3106 eligible patients, 286 were excluded because of missing or inadequate chest radiographs, leaving 2820 patients (mean age 50, 40% men) of whom 140 (5%) had pneumonia. Re-assessment of a subset of 1675 chest radiographs showed agreement in 94% (κ 0.45, 95% confidence interval 0.36 to 0.54). Six published "symptoms and signs models" varied in their discrimination (area under receiver operating characteristics curve (ROC) ranged from 0.55 (95% confidence interval 0.50 to 0.61) to 0.71 (0.66 to 0.76)). The optimal combination of clinical prediction items derived from our patients included absence of runny nose and presence of breathlessness, crackles and diminished breath sounds on auscultation, tachycardia, and fever, with an ROC area of 0.70 (0.65 to 0.75). Addition of CRP at the optimal cut off of >30 mg/L increased the ROC area to 0.77 (0.73 to 0.81) and improved the diagnostic classification (net reclassification improvement 28%). In the 1556 patients classified according to symptoms, signs, and CRP >30 mg/L as "low risk" (<2.5%) for pneumonia, the prevalence of pneumonia was 2%. In the 132 patients classified as "high risk" (>20%), the prevalence of pneumonia was 31%. The positive likelihood ratio of low, intermediate, and high risk for pneumonia was 0.4, 1.2, and 8.6 respectively. Measurement of procalcitonin added no relevant additional diagnostic information. A simplified diagnostic score based on symptoms, signs, and CRP >30 mg/L resulted in proportions of pneumonia of 0.7%, 3.8%, and 18.2% in the low, intermediate, and high risk group respectively. A clinical rule based on symptoms and signs to predict pneumonia in patients presenting to primary care with acute cough performed best in patients with mild or severe clinical presentation. Addition of CRP concentration at the optimal cut off of >30 mg/L improved diagnostic information, but measurement of procalcitonin concentration did not add clinically relevant information in this group.
    BMJ (online) 01/2013; 346:f2450. · 17.22 Impact Factor

Publication Stats

3k Citations
962.74 Total Impact Points


  • 2002–2014
    • University Medical Center Utrecht
      • Julius Center for Health Sciences and Primary Care
      Utrecht, Utrecht, Netherlands
  • 2005–2013
    • University of Antwerp
      • Vaccine & infectious disease institute
      Antwerpen, Flanders, Belgium
    • Radboud University Medical Centre (Radboudumc)
      Nymegen, Gelderland, Netherlands
    • University of Milan
      Milano, Lombardy, Italy
    • Erasmushogeschool Brussel
      Bruxelles, Brussels Capital Region, Belgium
  • 2011–2012
    • University of Southampton
      • • Academic Unit of Primary Care and Population Science
      • • Department of Psychology
      Southampton, England, United Kingdom
    • Cardiff University
      • South East Wales Trials Unit
      Cardiff, WLS, United Kingdom
    • The Bracton Centre, Oxleas NHS Trust
      Дартфорде, England, United Kingdom
    • København Zoo
      København, Capital Region, Denmark
  • 1999–2003
    • Universiteit Utrecht
      • • Julius Centre for Health Sciences and Primary Care
      • • University Medical Center Utrecht
      Utrecht, Provincie Utrecht, Netherlands
  • 2001
    • McMaster University
      Hamilton, Ontario, Canada