What a difference a CRP makes. A prospective observational study on how point-of-care C-reactive protein testing influences antibiotic prescription for respiratory tract infections in Swedish primary health care

Perceptions of C-reactive Protein Measurement Among General Physicians: A Qualitative Study on Diagnostic Value, Clinical Dilemmas, and Professional Growth

Introduction C-reactive protein (CRP) is a widely used laboratory test for assessing infections, inflammatory diseases, and malignancies, playing a critical role in clinical diagnosis and management. Despite its utility, CRP measurement practices vary among physicians, often influenced by training and clinical experience. This study explores general physicians' perceptions of CRP measurement in clinical practice, focusing on its diagnostic value, associated dilemmas, and impact on clinical growth and decision-making. Methods This qualitative study employed thematic analysis to examine the perceptions of general physicians at Unnan City Hospital, Unnan, Japan regarding CRP measurement. Sixteen general physicians were selected through purposive sampling and participated in one-on-one semi-structured interviews. The interviews were conducted in Japanese, recorded, transcribed verbatim, and analyzed inductively to identify themes. The analysis involved iterative coding and extensive discussion among the research team to ensure the reliability and validity of the findings. Results Three main themes emerged from the analysis: the usefulness of CRP for diagnosis and collaboration, dilemmas associated with CRP usage, and clinical growth through reconsideration of CRP's importance. Physicians highlighted CRP's value in distinguishing inflammatory from non-inflammatory diseases, predicting clinical courses, and facilitating communication with specialists. However, dilemmas arose from discrepancies between CRP levels and clinical symptoms, the influence of various non-specific factors, and habitual testing driven by training, leading to unnecessary tests and diminished clinical skills. Participants recognized the need to view CRP as one of many diagnostic tools, cultivate a habit of questioning its necessity, and reflect on its use to enhance clinical reasoning and professional growth. Conclusions CRP measurement is a valuable diagnostic tool, but effective use requires a balanced and critical approach. Discrepancies between CRP levels and clinical symptoms can lead to over-reliance on laboratory results and unnecessary testing. General physicians should integrate CRP within a broader diagnostic framework, combining it with patient history, physical examination, and other tests. Reflecting on the necessity and implications of CRP measurements can improve clinical reasoning and decision-making, ultimately enhancing patient care and resource management. Future research should explore similar perceptions in diverse healthcare settings and develop strategies to optimize CRP use in clinical practice.

Availability and use of rapid diagnostic tests for the management of acute childhood infections in Europe: A cross-sectional survey of paediatricians

BACKGROUND

Point-of-care-tests (POCTs) have been advocated to optimise care in patients with infections but their actual use varies. This study aimed to estimate the variability in the adoption of current POCTs by paediatricians across Europe, and to explore the determinants of variability.

METHODS AND FINDINGS

A cross-sectional survey was conducted of hospital and primary care paediatricians, recruited through professional networks. Questions focused on the availability and use of currently available POCTs. Data were analysed descriptively and using Median Odds Ratio (MOR) to measure variation between countries. Multilevel regression modelling using changes in the area under the receiver operating characteristic curve of models were used to assess the contribution of individual or workplace versus country level factors, to the observed variation. The commonest POCT was urine dipsticks (UD) which were available to >80% of primary care and hospital paediatricians in 68% (13/19) and 79% (23/29) countries, respectively. Availability of all POCTs varied between countries. In primary care, the country (MOR) varied from 1.61 (95%CI: 1.04-2.58) for lactate to 7.28 (95%CI: 3.04-24.35) for UD. In hospitals, the country MOR varied from 1.37 (95%CI:1.04-1.80) for lactate to 11.93 (95%CI:3.35-72.23) for UD. Most paediatricians in primary care (69%, 795/1154) and hospital (81%, 962/1188) would use a diagnostic test in the case scenario of an infant with undifferentiated fever. Multilevel regression modelling showed that the country of work was more important in predicting both the availability and use of POCTs than individual or workplace characteristics.

CONCLUSION

There is substantial variability in the adoption of POCTs for the management of acute infections in children across Europe. To inform future implementation of both existing and innovative tests, further research is needed to understand what drives the variation between countries, the needs of frontline clinicians, and the role of diagnostic tests in the management of acute childhood infections.

Introducing the C-reactive protein point-of-care test: A conversation analytic study of primary care consultations for respiratory tract infection

The C-reactive protein point-of-care test (CRP-POCT) can help distinguish between viral and bacterial infection and has been promoted as a strategy to improve antimicrobial stewardship. The test is widely used in Sweden. National guidelines advocate conservative use in primary care consultations with patients presenting with symptoms of respiratory tract infection (RTI). Previous research suggests low adherence to guidelines. We provide new insights into the communication surrounding the CRP-POCT by documenting how the decision to administer the test is interactionally motivated and organized in Swedish primary care. The data consists of video-recordings of RTI-consultations. A CRP-POCT was performed in nearly two thirds of the consultations and our study is focused on a subset where the test is ordered by a medical doctor. We find that doctors order the test during the transition from or after physical examination, a practice that aligns with national guidelines. Guidelines indicate that pathological findings from physical examination are warrants for ordering the test but we only found one example where this was communicated to the patient. A more prevalent pattern was that doctors ordered the CRP-POCT even though the outcome of the physical examination was assessed as normal. Our analyses of these show that doctors can provide the rationale for ordering the test in subtle ways and that failure to provide a rationale is treated as a noticeable absence. We also find that the CRP-POCT can be used to reconcile the contrast between the normal physical examination and the patient's problem presentation. Doctors can also order the test in ways that position the CRP-POCT as criterial for antibiotic prescription. Consultations where the patients described the symptoms as particularly severe and/or persistent were more likely to engender elaborate accounts than consultations where patients presented their symptoms as less problematic.

Impact of educational training and C-reactive protein point-of-care testing on antibiotic prescribing in rural and urban family physician practices in Latvia: a randomised controlled intervention study

BACKGROUND

Although self-limiting viral infections are predominant, children with acute infections are often prescribed antibiotics by family physicians. The aim of the study is to evaluate the impact of two interventions, namely C-reactive protein point-of-care testing and educational training, on antibiotic prescribing by family physicians.

METHODS

This randomised controlled intervention study included acutely ill children consulted by 80 family physicians from urban and rural practices in Latvia. The family physicians were divided into two groups of 40. The family physicians in the intervention group received both interventions, i.e. C-reactive protein point-of-care testing and educational training, whereas the family physicians in the control group continued to dispense their standard care. The primary outcome measure was the antibiotic prescribing at the index consultation (delayed or immediate prescription) in both study groups. The secondary outcome was CRP testing per study group. Patient- and family physician- related predictors of antibiotic prescribing were analysed as associated independent variables. Practice location effect on the outcomes was specially addressed, similar to other scientific literature.

RESULTS

In total, 2039 children with acute infections were enrolled in the study. The most common infections observed were upper and lower respiratory tract infections. Overall, 29.8% (n = 607) of the study population received antibiotic prescription. Our binary logistic regression analysis did not find a statistically significant association between antibiotic prescriptions and the implemented interventions. In the control group of family physicians, a rural location was associated with more frequent antibiotic prescribing and minimal use of CRP testing of venous blood samples. However, in the intervention group of family physicians, a rural location was associated with a higher level of C-reactive protein point-of-care testing. Furthermore, in rural areas, a significant reduction in antibiotic prescribing was observed in the intervention group compared with the control group (29.0% (n = 118) and 37.8% (n = 128), respectively, p = 0.01).

CONCLUSION

Our results show that the availabilty of C-reactive protein point-of-care testing and educational training for family physicians did not reduce antibiotic prescribing. Nevertheless, our data indicate that regional variations in antibiotic-prescribing habits exist and the implemented interventions had an effect on family physicians practices in rural areas.

Prescribing antibiotics: Factors driving decision-making in general practice. A discrete choice experiment

BACKGROUND

Antimicrobial resistance is a threat to human health. We need to strive for a rational use of antibiotics to reduce the selection of resistant bacteria. Most antibiotics are prescribed in general practice, but little is known about factors influencing general practitioners' (GPs) decision-making when prescribing antibiotics.

AIM

To 1) assess the importance of factors that influence decisions by GPs to prescribe antibiotics for acute respiratory tract infections (RTIs) and 2) identify segments of GPs influenced differently when deciding to prescribe antibiotics.

METHODS

A questionnaire survey including a discrete choice experiment was conducted. Danish GPs were asked to indicate whether they would prescribe antibiotics in six hypothetical choice sets with six variables: whether the GP is behind schedule, patient's temperature, patient's general condition, lung auscultation findings, C-reactive protein (CRP) level, and whether the patient expects antibiotics. Error component and latent class models were estimated and the probabilities of prescribing in different scenarios were calculated.

RESULTS

The questionnaire was distributed to every Danish GP (n = 3,336); 1,152 (35%) responded. Results showed that GPs were influenced by (in prioritised order): CRP level (Relative importance (RI) 0.54), patient's general condition (RI 0.20), crackles at auscultation (RI 0.15), and fever (RI 0.10). Being behind schedule and patient expectations had no significant impact on antibiotic prescription at the aggregate level. The latent class analysis identified five classes of GPs: generalists, CRP-guided, general condition-guided, reluctant prescribers, and stethoscopy-guided. For all classes, CRP was the most important driver, while GPs were heterogeneously affected by other drivers.

CONCLUSION

The most important factor affecting Danish GPs' decision to prescribe antibiotics at the aggregate level, in subgroups of GPs, and across latent classes was the CRP value. Hence, the use of CRP testing is an important factor to consider in order to promote rational antibiotic use in the battle against antimicrobial resistance.

Diagnoses Based on C-Reactive Protein Point-of-Care Tests

C-reactive protein (CRP) is an important part of the immune system's reaction to various pathological impulses such as bacterial infections, systemic inflammation, and internal organ failures. An increased CRP level serves to diagnose the mentioned pathological states. Both standard laboratory methods and simple point-of-care devices such as lateral flow tests and immunoturbidimetric assays serve for the instrumental diagnoses based on CRP. The current method for CRP has many flaws and limitations in its use. Biosensor and bioassay analytical devices are presently researched by many teams to provide more sensitive and better-suited tools for point-of-care tests of CRP in biological samples when compared to the standard methods. This review article is focused on mapping the diagnostical relevance of CRP, the applicability of the current analytical methods, and the recent innovations in the measurement of CRP level.

Antibiotic use in Australian and Swedish primary care: a cross-country comparison

OBJECTIVE

Antimicrobial resistance is a growing worldwide problem and is considered to be one of the biggest threats to global health by the World Health Organization. Insights into the determinants of antibiotic prescribing may be gained by comparing the antibiotic usage patterns of Australia and Sweden.

DESIGN

Publicly available data on dispensed use of antibiotics in Australia and Sweden between 2006 and 2018. Medicine use was measured using defined daily dose per 1,000 inhabitants per day (DDD/1000/day) and the number of dispensed prescriptions per 1000 inhabitants (prescriptions/1000).

RESULTS

The use of antibiotics increased over the study period in Australia by 1.8% and decreased in Sweden by 26.3%. Use was consistently higher in Australia, double that of Sweden in 2018. Penicillin with extended spectrum was the most used class of antibiotics in Australia followed by penicillin with beta lactamase inhibitors. In Sweden, the most used class was beta lactamase-sensitive penicillin and the least used class was penicillin with beta lactamase inhibitors.

CONCLUSION

Antibiotic use in Australia is higher than in Sweden, with a higher proportion of broad-spectrum penicillin, including combinations with beta lactamase inhibitors, and cephalosporins. Factors that may contribute to these differences in antibiotic use include differences in guidelines, the duration of national antimicrobial stewardship programs, and differences in funding mechanisms.Key pointsAustralia has had a consistently higher dispensed use of antibiotics compared to Sweden from 2006 to 2018; and up to twice the use in 2018•A higher proportion of dispensed antibiotics in Australia were broad-spectrum penicillin, including combinations with beta lactamase inhibitors, and cefalosporins.•The most commonly used class of antibiotics in Australia is penicillin with extended spectrum, compared to beta lactamase sensitive penicillin in Sweden.•Use of macrolides, sulphonamides and trimethoprim, cephalosporins, penicillin with beta lactamase inhibitors and penicillin with extended spectrum was consistently higher in Australia, whereas in Sweden use of fluoroquinolones, lincosamides, beta lactamase-resistant penicillin and beta lactamase sensitive penicillin was higher.•The observed differences could be explained by antibiotic choice recommended in guidelines, prevalence of point-of-care testing, models of primary care funding, the presence and duration of national antimicrobial stewardship programmes, and cultural differences.

Factors associated with C-reactive protein testing when prescribing antibiotics in general practice: a register-based study

BACKGROUND

The use of C-reactive protein (CRP) tests has been shown to safely reduce antibiotic prescribing for acute respiratory tract infections (RTIs). The aim of this study was to explore patient and clinical factors associated with the use of CRP testing when prescribing antibiotics recommended for RTIs.

METHODS

A nation-wide retrospective cross-sectional register-based study based on first redeemed antibiotic prescriptions issued to adults in Danish general practice between July 2015 and June 2017. Only antibiotics recommended for treatment of RTIs were included in the analysis (penicillin-V, amoxicillin, co-amoxicillin or roxithromycin/clarithromycin). Logistic regression models were used to estimate odds ratios for patient-related and clinical factors on performing a CRP test in relation to antibiotic prescribing.

RESULTS

A total of 984,149 patients redeemed at least one antibiotic prescription during the two-year period. About half of these prescriptions (49.6%) had an RTI stated as the indication, and a CRP test was performed in relation to 45.2% of these scripts. Lower odds of having a CRP test performed in relation to an antibiotic prescription was found for patients aged 75 years and above (OR 0.82, 95CI 0.79-0.86), with a Charlson Comorbidity Index of more than one (OR 0.93, 95CI 0.91-0.95), unemployed or on disability pension (OR 0.84, 95CI 0.83-0.85) and immigrants (OR 0.91, 95CI 0.88-0.95) or descendants of immigrants (OR 0.90, 95CI 0.84-0.96). Living with a partner (OR 1.08, 95CI 1.07-1.10), being followed in practice for a chronic condition (OR 1.22, 95CI 1.18-1.26) and having CRP tests performed in the previous year (OR 1.78, 95CI 1.73-1.84) were associated with higher odds of CRP testing in relation to antibiotic prescribing.

CONCLUSIONS

Differences were observed in the use of CRP tests among subgroups of patients indicating that both sociodemographic factors and comorbidity influence the decision to use a CRP test in relation to antibiotic prescriptions in general practice. Potentially, this means that the use of CRP tests could be optimised to increase diagnostic certainty and further promote rational prescribing of antibiotics. The rationale behind the observed differences could be further explored in future qualitative studies.

Latvian Primary Care Management of Children with Acute Infections: Antibiotic-Prescribing Habits and Diagnostic Process Prior to Treatment

Background and Objectives: Primary care physicians frequently prescribe antibiotics for acutely ill children, even though they usually have self-limiting diseases of viral etiology. The aim of this research was to evaluate the routine antibiotic-prescribing habits of primary care in Latvia, in response to children presenting with infections. Materials and Methods: This cross-sectional study included acutely ill children who consulted eighty family physicians (FP) in Latvia, between November 2019 and May 2020. The data regarding patient demographics, diagnoses treated with antibiotics, the choice of antibiotics and the use of diagnostic tests were collected. Results: The study population comprised 2383 patients aged between one month and 17 years, presenting an acute infection episode, who had a face-to-face consultation with an FP. Overall, 29.2% of these patients received an antibiotic prescription. The diagnoses most often treated with antibiotics were otitis (45.8% of all antibiotic prescriptions), acute bronchitis (25.0%) and the common cold (14.8%). The most commonly prescribed antibiotics were amoxicillin (55.9% of prescriptions), amoxicillin/clavulanate (18.1%) and clarithromycin (11.8%). Diagnostic tests were carried out for 59.6% of children presenting with acute infections and preceded 66.4% of antibiotic prescriptions. Conclusion: Our data revealed that a high level of antibiotic prescribing for self-limiting viral infections in children continues to occur. The underuse of narrow-spectrum antibiotics and suboptimal use of diagnostic tests before treatment decision-making were also identified. To achieve a more rational use of antibiotics in primary care for children with a fever, professionals and parents need to be better educated on this subject, and diagnostic tests should be used more extensively, including the implementation of daily point-of-care testing.

Heart Failure and Diabetes Mellitus: Biomarkers in Risk Stratification and Prognostication

Heart failure (HF) and type 2 diabetes mellitus (T2DM) have a synergistic effect on cardiovascular (CV) morbidity and mortality in patients with established CV disease (CVD). The aim of this review is to summarize the knowledge regarding the discriminative abilities of conventional and novel biomarkers in T2DM patients with established HF or at higher risk of developing HF. While conventional biomarkers, such as natriuretic peptides and high-sensitivity troponins demonstrate high predictive ability in HF with reduced ejection fraction (HFrEF), this is not the case for HF with preserved ejection fraction (HFpEF). HFpEF is a heterogeneous disease with a high variability of CVD and conventional risk factors including T2DM, hypertension, renal disease, older age, and female sex; therefore, the extrapolation of predictive abilities of traditional biomarkers on this population is constrained. New biomarker-based approaches are disputed to be sufficient for improving risk stratification and the prediction of poor clinical outcomes in patients with HFpEF. Novel biomarkers of biomechanical stress, fibrosis, inflammation, oxidative stress, and collagen turn-over have shown potential benefits in determining prognosis in T2DM patients with HF regardless of natriuretic peptides, but their role in point-to-care and in routine practice requires elucidation in large clinical trials.

C-reactive protein influences the doctor's degree of suspicion of pneumonia in primary care: a prospective observational study

BACKGROUND

In primary care, the diagnosis of pneumonia is often based on history and clinical examination alone. However, a previous study showed that the general practitioner's degree of suspicion correlates well with findings on chest X-ray, when the C-reactive protein (CRP) value is known.

OBJECTIVES

The present study aimed to investigate to what extent the physician's degree of suspicion is affected by the CRP level when community-acquired pneumonia is suspected in primary care.

METHODS

A prospective observational study was conducted at five primary health care centres in Sweden between October 2015 and December 2017. Adult patients (n = 266) consulting their health care centre with symptoms of lower respiratory tract infection, where the physician suspected pneumonia, were included consecutively. Anamnestic information and findings from clinical examination were documented in a case report form. All patients were tested for CRP. The physicians rated their degree of suspicion as 'unsure,' 'quite sure,' and 'sure' before and after the CRP result.

RESULTS

The degree of suspicion of pneumonia changed in 69% of the cases; most often to a lower degree (40%). In 28% of the cases, there was no longer any suspicion of pneumonia after CRP.

CONCLUSION

Our results indicate that CRP testing highly influences the physician's degree of suspicion of pneumonia in primary care and that it seems to be of most value when not sure of the diagnosis.

Variation in Early Inflammatory Marker Testing for Infection-Related Hospitalizations in Children

BACKGROUND AND OBJECTIVES

Inflammatory marker testing in children has been identified as a potential area of overuse. We sought to describe variation in early inflammatory marker (C-reactive protein and erythrocyte sedimentation rate) testing for infection-related hospitalizations across children's hospitals and to determine its association with length of stay (LOS), 30-day readmission rate, and cost.

METHODS

We conducted a cross-sectional study of children aged 0 to 17 years with infection-related hospitalizations using the Pediatric Health Information System. After adjusting for patient characteristics, we examined rates of inflammatory marker testing (C-reactive protein or erythrocyte sedimentation rate) during the first 2 days of hospitalization. We used k-means clustering to assign each hospital to 1 of 3 groups on the basis of similarities in adjusted diagnostic testing rates across 12 infectious conditions. Multivariable regression was used to examine the association between hospital testing group and outcomes.

RESULTS

We included 55 771 hospitalizations from 48 hospitals. In 7945 (14.3%), there was inflammatory marker testing in the first 2 days of hospitalization. We observed wide variation in inflammatory marker testing rates across hospitals and infections. Group A hospitals tended to perform more tests than group B or C hospitals (37.4% vs 18.0% vs 10.4%; P < .001) and had the longest adjusted LOS (3.2 vs 2.9 vs 2.8 days; P = .01). There was no significant difference in adjusted 30-day readmission rates or costs.

CONCLUSIONS

Inflammatory marker testing varied widely across hospitals. Hospitals with higher inflammatory testing for one infection tend to test more frequently for other infections and have longer LOS, suggesting opportunities for diagnostic stewardship.

Change in the use of diagnostic tests in the management of lower respiratory tract infections: a register-based study in primary care

Background

Differentiating between pneumonia and acute bronchitis is often difficult in primary care. There is no consensus regarding clinical decision rules for pneumonia, and guidelines differ between countries. Use of diagnostic tests and change of management over time is not known.

Aim

To calculate the proportion of diagnostic tests in the management of lower respiratory tract infections (LRTIs) in a low antibiotic prescribing country, and to evaluate if the use and prescription pattern has changed over time.

Design & setting

A register-based study on data from electronic health records from January 2006 to December 2014 in the Kronoberg county of south east Sweden.

Method

Data regarding use of C-reactive protein (CRP), chest x-rays (CXRs), microbiological tests, and antibiotic prescriptions were assessed for patients aged 18–79 years, with the diagnosis pneumonia, acute bronchitis, or cough.

Results

A total of 54 229 sickness episodes were analysed. Use of CRP increased during the study period from 61.3% to 77.5% for patients with pneumonia (P<0.001), and from 53.4% to 65.7% for patients with acute bronchitis (P<0.001). Use of CXR increased for patients with acute bronchitis from 3.1% to 5.1% (P<0.001). Use of microbiological tests increased for patients with pneumonia, from 1.8% to 5.1% (P<0.001). The antibiotic prescription rate decreased from 18.6 to 8.2 per 1000 inhabitants per year for patients with acute bronchitis, but did not change for patients with pneumonia.

Conclusion

Use of CRP and microbiological tests in the diagnostics of LRTIs increased despite the fact that the incidence of pneumonia and acute bronchitis was stable.

A study of guidelines for respiratory tract infections and their references from Swedish GPs: a qualitative analysis

Background: National guidelines are important instruments in reducing inappropriate antibiotic prescriptions. Low adherence to guidelines is an acknowledged problem that needs to be addressed.Method: We evaluated established characteristics for guidelines in the guidelines for lower respiratory tract infection, acute otitis media and pharyngotonsillitis in primary care. We studied how doctors used these guidelines by analysing interviews with 29 general practitioners (GPs) in Sweden.Results: We found important between-guidelines differences, which we believe affects adherence. The GPs reported persistent preconceptions about diagnosis and treatment, which we believe reduces their adherence to the guidelines.Conclusion: To increase adherence, it is important to consider doctors' preconceptions when creating new guidelines.

Impact of point-of-care C reactive protein in ambulatory care: a systematic review and meta-analysis

OBJECTIVE

The aim of this review was to collate all available evidence on the impact of point-of-care C reactive protein (CRP) testing on patient-relevant outcomes in children and adults in ambulatory care.

DESIGN

This was a systematic review to identify controlled studies assessing the impact of point-of-care CRP in patients presenting to ambulatory care services. Ovid Medline, Embase, Cochrane Database of Systematic Reviews, Cochrane CENTRAL, DARE, Science Citation Index were searched from inception to March 2017.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Controlled studies assessing the impact of point-of-care CRP in patients presenting to ambulatory care services, measuring a change in clinical care, including but not limited to antibiotic prescribing rate, reconsultation, clinical recovery, patient satisfaction, referral and additional tests. No language restrictions were applied.

DATA EXTRACTION

Data were extracted on setting, date of study, a description of the intervention and control group, patient characteristics and results. Methodological quality of selected studies and assessment of potential bias was assessed independently by two authors using the Cochrane Risk of Bias tool.

RESULTS

11 randomised controlled trials and 8 non-randomised controlled studies met the inclusion criteria, reporting on 16 064 patients. All included studies had a high risk of performance and selection bias. Compared with usual care, point-of-care CRP reduces immediate antibiotic prescribing (pooled risk ratio 0.81; 95% CI 0.71 to 0.92), however, at considerable heterogeneity (I2=72%). This effect increased when guidance on antibiotic prescribing relative to the CRP level was provided (risk ratios of 0.68; 95% CI 0.63 to 0.74 in adults and 0.56; 95% CI 0.33 to 0.95 in children). We found no significant effect of point-of-care CRP testing on patient satisfaction, clinical recovery, reconsultation, further testing and hospital admission.

CONCLUSIONS

Performing a point-of-care CRP test in ambulatory care accompanied by clinical guidance on interpretation reduces the immediate antibiotic prescribing in both adults and children. As yet, available evidence does not suggest an effect on other patient outcomes or healthcare processes.

PROSPERO REGISTRATION NUMBER

CRD42016035426; Results.

A systematic evaluation of immunoassay point-of-care testing to define impact on patients' outcomes

Background Point-of-care testing has been developed to provide rapid test results. Most published studies focus on analytical performance, neglecting its impact on patient outcomes. Objective To review the analytical performance and accuracy of point-of-care testing specifically planned for immunoassay and to evaluate the impact of faster results on patient management. Methods A search of electronic databases for studies reporting immunoassay results obtained in both point-of-care testing and central laboratory scenarios was performed. Data were extracted concerning the study details, and the methodological quality was assessed. The analytical characteristics and diagnostic accuracy of six points-of-care testing: troponin, procalcitonin, parathyroid hormone, brain natriuretic peptide, C-reactive protein and neutrophil gelatinase-associated lipocalin were evaluated. Results A total of 116 scientific papers were analysed. Studies measuring procalcitonin, parathyroid hormone and neutrophil gelatinase-associated lipocalin reported a limited impact on diagnostic decisions. Seven studies measuring C-reactive protein claimed a significant reduction of antibiotic prescription. Several authors evaluated brain natriuretic peptide or troponin reporting faster decision-making without any improvement in clinical outcome. Forty-four per cent of studies reported analytical data, showing satisfactory correlations between results obtained through point-of-care testing and central laboratory setting. Half of studies defined the diagnostic accuracy of point-of-care testing as acceptable for troponin (median sensitivity and specificity: 74% and 94%, respectively), brain natriuretic peptide (median sensitivity and specificity: 82% and 88%, respectively) and C-reactive protein (median sensitivity and specificity 85%). Conclusions Point-of-care testing immunoassay results seem to be reliable and accurate for troponin, brain natriuretic peptide and C-reactive protein. The satisfactory analytical performance, together with an excellent practicability, suggests that it could be a consistent tool in clinical practice, but data are lacking regarding the patient outcomes.

Out-of-hours antibiotic prescription after screening with C reactive protein: a randomised controlled study

OBJECTIVE

To evaluate the effect of preconsultation C reactive protein (CRP) screening on antibiotic prescribing and referral to hospital in Norwegian primary care settings with low prevalence of serious infections.

DESIGN

Randomised controlled observational study at out-of-hours services in Norway.

SETTING

Primary care.

PARTICIPANTS

401 children (0-6 years) with fever and/or respiratory symptoms were recruited from 5 different out-of-hours services (including 1 paediatric emergency clinic) in 2013-2015.

INTERVENTION

Data were collected from questionnaires and clinical examination results. Every third child was randomised to a CRP test before the consultation; for the rest, the doctor ordered a CRP test if considered necessary.

OUTCOME MEASURES

Main outcome variables were prescription of antibiotics and referral to hospital.

RESULTS

In the group pretested with CRP, the antibiotic prescription rate was 26%, compared with 22% in the control group. In the group pretested with CRP, 5% were admitted to hospital, compared with 9% in the control group. These differences were not statistically significant. The main predictors for ordering a CRP test were parents' assessment of seriousness of the illness and the child's temperature. Paediatricians ordered CRP tests less frequently than did other doctors (9% vs 56%, p<0.001).

CONCLUSIONS

Preconsultation screening with CRP of children presenting to out-of-hours services with fever and/or respiratory symptoms does not significantly affect the prescription of antibiotics or referral to hospital.

TRIAL REGISTRATION NUMBER

NCT02496559; Results.