C-reactive Protein Test Research Articles

Systemic inflammation and risk of death in patients with atherosclerotic cardiovascular disease and chronic kidney disease

Abstract Background Atherosclerotic cardiovascular disease (ASCVD) and chronic kidney disease stage 3 - 4 (CKD) affects 7% and 10% of the Danish population, respectively. Systemic inflammation (SI) contributes to destabilisation of atherosclerotic plaques and is characterized by elevated levels of C-reactive protein (CRP) in the blood. CKD is associated with SI and is independently associated with an increased risk of ASCVD. CRP levels ≥2 mg/L have been identified as a risk factor for mortality and major adverse cardiovascular events (MACE). Purpose To provide real-world evidence on the clinical burden of SI in patients diagnosed with ASCVD and CKD, using national health registers. Method Data from the Danish National Patient Registry from 1994-2022 was used to identify ASCVD patients by ICD-10 codes. CKD was identified by eGFR test results in the range [15 -59mL/min/1.73m2], in the Register of Laboratory Results for Research (RLRR). The latter diagnosis of ASCVD and CKD was set as index date. CRP-test results were extracted from RLRR and only individuals with at least two CRP tests were included. If two CRP-test results ≥2mg/L to < 20mg/L were observed less than six month apart, and within two years of index date, the individual was classified to have SI. The eGFR data from RLRR was available from 2011 onwards, with some regional differences in reporting. Individuals observed with CKD or ASCVD in the first year of eGFR availability were excluded to ensure a study of incident individuals. Individuals using select medications or diagnosed with selected chronic conditions thought to influence CRP levels were excluded. Additional population characteristics were extracted from corresponding national health and administrative registers. Hazard of all-cause mortality and MACE was analysed in a Cox proportional risk regression. Results From 2012 to 2022, a total of 19,162 individuals were eligible for the study population (SI: 13,039, No SI: 6,123). Median follow-up time was 4.1 and 8.2 years for individuals with or without SI, respectively. Median CRP two years before and after index date in the two groups was 7mg/L and 1mg/L. No clinically significant differences were found for demographic or socioeconomic characteristics. Patients with SI had more frequent history of hypertension, atrial fibrillation, COPD, heart failure and Type 2 diabetes before index, and higher risk of hypertension, atrial fibrillation, stroke, heart failure and type 2 diabetes after index. SI population had significantly increased hazard of mortality in a crude model (HR: 2.35, 95% CI: [2.22 – 2.50]), and in adjusted analysis HR: 2.06 ([1.92 - 2.21]). The corresponding hazard ratios for MACE were 1.9 ([1.81 – 2.01]) and 1.66 ([1.57 – 1.77]). The results were consistent across different model specifications and subgroups. Conclusion SI is associated with a significantly higher clinical burden of disease and a higher risk of all-cause mortality.Flowchart of inclusion/exclusionHazard ratio, overall and by subgroup

Characterization of individuals with atherosclerotic cardiovascular disease, with and without chronic kidney disease: results from a UK electronic health record database

Abstract Introduction Elevated C-reactive protein (CRP) levels are often present in individuals with atherosclerotic cardiovascular disease (ASCVD), including in those who also have chronic kidney disease (CKD), and are associated with an increased risk of major adverse cardiovascular events (MACE). To understand unmet needs in the identification and management of at-risk individuals, we characterized patients with ASCVD in a UK database, according to CKD stage and CRP levels. Methods This study comprised separate retrospective cross-sectional and longitudinal cohort analyses of patients in the Clinical Practice Research Datalink (CPRD) Aurum database, a representative UK database of anonymized primary care records. In the cross-sectional analysis, CPRD Aurum was linked with Hospital Episode Statistics (HES) and Index of Multiple Deprivation data to assess patient characteristics on 1 Jan 2021 (defined as index date). In the cohort analysis, CPRD Aurum was linked with HES and Office for National Statistics mortality data to determine the incidence of 3-point MACE (3P-MACE) over approximately 5 years of follow-up (index date: 1 Jan 2016). Both analyses included individuals ≥ 18 years old with an ASCVD diagnosis in both primary and secondary care in the 5 years pre-index. Data were analysed using descriptive statistics. Patient characteristics were assessed by CKD stage; for individuals with CKD stage 3–4, characteristics were also assessed by CRP levels. Results In total, 225,767 and 230,055 individuals were included in the cross-sectional and cohort analyses, respectively. The prevalence of CKD stage 3–4 among individuals with ASCVD was 24.3% (Table 1). The proportion of individuals with elevated CRP (CRP ≥ 2 mg/L) and anaemia increased for successively higher CKD severity groups; in addition, glycated haemoglobin (HbA1c) ≥ 7% and elevated blood pressure were generally more frequently observed in individuals with CKD than in those without (Table 1). Individuals with ASCVD, CKD stage 3–4 and elevated CRP had higher HbA1c and total cholesterol levels and a greater proportion had obesity, anaemia and elevated blood pressure, compared with individuals with CRP < 2 mg/L (Table 2). Over 5 years’ follow-up, the incidence of 3P-MACE increased with CKD severity (Table 1) and with increasing CRP levels in individuals with ASCVD and CKD stage 3–4 (Table 2). However, only 28% of individuals with ASCVD and CKD stage 3–4 had CRP measurements. Conclusion Adults with ASCVD, CKD and elevated CRP identified from primary and secondary UK care records had a higher disease burden than individuals with CRP levels < 2 mg/L. In the UK, testing CRP levels is not routinely recommended, resulting in a high proportion of missing CRP measurements in this study. Routine testing of CRP may help in identifying patients with residual cardiovascular risk and has the potential to support risk assessment and management of patients with ASCVD and CKD.

C-reactive protein after discharge and infarct size in patients with ST segment elevation myocardial infarction

Abstract Background C-reactive protein (CRP) peaks at 2 days in patients with ST-segment elevation myocardial infarction (STEMI) after percutaneous coronary intervention (PCI) and can predict final infarct size. It is, however, unknown whether CRP level after discharge, indicative of prolonged inflammation, plays a prognostic role in myocardial damage. Purpose To investigate the prevalence of high CRP level within 3 months after discharge in patients with STEMI and its association with myocardial damage. Methods In the current study, all patients were identified through the xx database and treated with timely PCI at xx hospital from 2011 to 2014. Blood samples were retrieved within 3 months after discharge. High CRP level was defined as CRP >=3 mg/L. Only patients with a cardiac magnetic resonance (CMR) at baseline or follow-up were recruited. The primary outcome was final infarct size. Multiple regression was performed to adjust for potential confounders using any baseline variable with P<0.10 for the difference between groups. Results Of the 1603 patients from xx, 273 patients had CRP measured following discharge and at least one CMR measured. Of them, 200 (73.3%) had high CRP level after discharge. There was no difference in period from PCI to CRP testing between patients with high CRP and those with low CRP [11 days, interquartile range (IQR) (4, 40) vs. 21 days, IQR (4, 42), P=0.31]. Patients with high CRP level showed larger final infarct size [12.5% left ventricle (LV) vs. 7.0% LV, P <0.001] and larger acute infarct size [15.2% LV vs. 10.6% LV, p=0.004] compared with those with low CRP level. Patients with high CRP level also had lower final myocardial salvage index (MSI) (0.67 vs. 0.75, P=0.003) and lower acute MSI (0.47 vs. 0.61, P=0.006). The results persisted after adjusting for potential confounders in multiple regression. Conclusions A large proportion of patients with STEMI undergoing PCI persisted high CRP within 3 months after discharge. High CRP level after discharge was associated with larger acute and final infarct size as well as lower acute and final MSI level.

Burden of systemic inflammation and associated health outcomes in adults with atherosclerotic cardiovascular disease managed in routine care

Abstract Background The burden and outcomes of inflammation in people with atherosclerotic cardiovascular disease (ASCVD) are poorly defined, particularly beyond the controlled settings of trials and research cohorts. Methods We conducted a longitudinal observational study of adults with ASCVD undergoing C-reactive-protein (CRP) testing in routine healthcare in Stockholm, Sweden. After excluding CRP tests associated with acute illness and patients with medications/conditions that bias CRP interpretation, the systemic inflammation of participants was defined over a 3-month ascertainment window. Baseline determinants of CRP≥2 mg/L were explored with logistic regression, and baseline CRP categories were compared via Poisson and Cox regression for subsequent healthcare resource utilization and occurrence of major adverse cardiovascular events (MACE), heart failure hospitalization, and all-cause death. Result After applying inclusion/exclusion criteria, we identified 84,399 adults with ASCVD with a mean age of 71 years and of which 54% were men. In total, 60% had CRP≥2 mg/L. At baseline, female sex, older age, lower kidney function, albuminuria, diabetes, hypertension, and recent anemia, were associated with CRP≥2 mg/L. Conversely, the use of RASi, antiplatelets, and lipid-lowering therapy were associated with lower odds. Over a median follow-up of 6.4 years and compared to people with CRP <2 mg/L, those with CRP≥2 mg/L had a higher rate of hospitalizations, days spent in hospital, outpatient consultations, and dispensed medications during follow-up (P<0.05 for all). They also had a higher rate of MACE [adjusted hazard ratio (HR), 1.30; 95% CI, 1.27–1.33], heart failure hospitalization [1.24; 1.20–1.39], and all-cause death [1.35; 1.20–1.30]. Results were consistent across subgroups and more granular CRP categories, and robust to the exclusion of extreme CRP values or early events. Conclusions Two in three adults with ASCVD have systemic inflammation. A CRP≥2 mg/L is associated with excess healthcare resource utilization as well as increased rates of MACE, heart failure, and death.

Use of point-of-care tests in pharyngotonsillitis – a registry-based study in primary health care

Background Point-of-care (POC) tests, including C-reactive protein (CRP) tests and rapid antigen detection tests (RADT) for group A streptococci (GAS), are widely used in Swedish primary health care (PHC). This study quantifies their use in pharyngotonsillitis and explore their association with antibiotic prescribing. Material and methods Retrospective data from 2012–2016 in Region Kronoberg, Sweden, included all PHC visits with a pharyngotonsillitis diagnosis. Patient characteristics, test usage and antibiotic prescriptions were linked by visit date and personal identification number. Descriptive statistics were used for POC test analysis. Logistic regression assessed the association between CRP levels and antibiotic prescribing. Results Of 24,237 visits, 68% included RADT and 36% included a CRP test, with 89% of CRP tests performed alongside RADT. CRP testing was more frequent in patients with negative (56%) than positive RADTs (42%) (p < .001). Overall, 66% of RADTs were positive. Median CRP levels were 23 mg/l for positive RADT and 31 mg/l for negative RADT (p < .001). Antibiotics were prescribed for 95% of positive RADTs and 43% of negative RADTs (p < .001). In patients with negative RADTs, CRP testing was associated with higher antibiotic prescribing (57%) compared to no CRP testing (26%) (p < .001). Among these patients, CRP levels were associated with prescribing (aOR 1.032; 95% CI 1.029–1.035; p < .001), with 50% of prescriptions occuring at CRP levels ≤ 20 mg/l. Conclusion The use of RADTs and the proportion of positive test were higher than expected, indicating inappropriate use and diagnostic bias. CRP testing, contrary to guidelines, was common and associated with increased antibiotic prescribing.

Prognostic Significance of Markers of Endothelial Dysfunction in Case of Severe Combined Blunt Abdominal Trauma

INTRODUCTION. In case of polytrauma, an imbalance occurs between substances produced by the endothelium, the rheological properties of the blood are disrupted, the content of procoagulants increases, the permeability of the vascular wall increases, which contributes to thrombus formation and increased tissue hypoxia, and subsequently to the development of multiple organ failure, and, of course, affects the course of traumatic disease, the development of complications and mortality. However, specific markers of endothelial dysfunction and their levels, by which it is possible to reliably predict the course of traumatic disease in severe combined closed abdominal trauma for the appropriate pathogenetic treatment have not yet been determined.AIM OF THE STUDY. To determine the significance of some markers of endothelial dysfunction (C-reactive protein, von Willebrand factor, the number of desquamated endothelial cells in the blood) in combined blunt abdominal trauma to predict the likelihood of complications and adverse outcomes.MATERIAL AND METHODS. The main group consisted of 31 patients with severe combined blunt abdominal trauma, the comparison group consisted of 5 patients operated on for large ventral hernias. All patients underwent blood tests for C-reactive protein, von Willebrand factor, the number of desquamated endothelial cells.RESULTS. The level of all three considered markers of endothelial dysfunction in severe abdominal trauma significantly differs from that in operated non-traumatized patients, which allows differential diagnostics to be made between abdominal wall contusion and damage to internal organs; extremely high values suggest an unfavorable course of traumatic disease and a high probability of a fatal outcome.CONCLUSION. Taking into account that the development of traumatic disease is based on damage to the vascular endothelium, it is necessary to consider as prognostic indicators changes in the level of activity of C-reactive protein, von Willebrand factor, desquamated endothelial cells in patients with severe combined blunt abdominal trauma.

Prospective cohort study on the clinical significance of interferon-γ, D-dimer, LDH, and CRP tests in children with severe mycoplasma pneumonia.

Mycoplasma pneumoniae is a significant cause of respiratory infections in children, often leading to severe pneumonia. This study aimed to assess the clinical relevance of interferon-gamma (interferon-γ), D-dimer, lactate dehydrogenase (LDH), and C-reactive protein (CRP) as biomarkers in the severity of mycoplasma pneumonia in pediatric patients. In this prospective study, 203 pediatric patients with mycoplasma pneumonia were classified into mild (123 patients) and severe (80 patients) groups. Biomarkers including interferon-γ, D-dimer, LDH, and CRP were measured and analyzed. Statistical methods employed included Pearson and Spearman correlation analyses, logistic regression, and receiver operating characteristic curve analysis. The severe group exhibited significantly higher median and interquartile ranges for interferon-γ, D-dimer, LDH, and CRP compared to the mild group. Logistic regression identified IL-10, IL-6, interferon-γ, tumor necrosis factor-alpha, D-dimer, and LDH as independent predictors of severity, with the model achieving 92% accuracy. Receiver operating characteristic curve analysis showed optimal diagnostic efficacy for interferon-γ, D-dimer, and LDH, with the best threshold values being 8.11, 0.64, and 379, respectively. A significant positive correlation was observed between IL-6 and LDH, as well as between interferon-γ and D-dimer. This study showed that interferon-γ >8.11, D-dimer >0.64, and LDH >379 have an important role in the assessment of severe mycoplasma pneumonia.

The performance of screening tools and use of blood analyses in prehospital identification of sepsis patients and patients suitable for non-conveyance - an observational study.

Early recognition of sepsis by the EMS (Emergency Medical Services), along with communicating this concern to the emergency department, could improve patient prognosis and outcome. Knowledge is limited about the performance of sepsis identification screening tools in the EMS setting. Research is also limited on the effectiveness of prehospital use of blood tests for sepsis identification. Integrating blood analyses with screening tools could improve sepsis identification, leading to prompt interventions and improved patient outcomes. The aim of the present study is firstly to evaluate the performance of various screening tools for sepsis identification in the EMS setting and secondly to assess the potential improvement in accuracy by incorporating blood analyses. This is a retrospective observational cohort study. The data were collected from prehospital and hospital medical records in Region Halland. Data on demographics, vital signs, blood tests, treatment, and outcomes were collected from patients suspected by EMS personnel of having infection. The data were analysed using Student's t-test. Sensitivity, specificity, positive predictive value, negative predictive value and odds ratio were used to indicate accuracy and predictive value. In total, 5,405 EMS missions concerning 3,225 unique patients were included. The incidence of sepsis was 9.8%. None of the eleven tools included had both high sensitivity and specificity for sepsis identification. White blood cell (WBC) count was the blood analysis with the highest sensitivity but the lowest specificity for identifying sepsis. Adding WBC, C-reactive protein (CRP) or lactate to the National Early Warning Score (NEWS) increased the specificity to > 80% but substantially lowered the sensitivity. Identifying sepsis in EMS settings remains challenging, with existing screening tools offering limited accuracy. CRP, WBC, and lactate blood tests add minimal predictive value in distinguishing sepsis or determining non-conveyance eligibility.

Fabrication of core-shell quantum dots microbeads with high stability, enhanced sensitivity and potential application in C-reactive protein (CRP) and procalcitonin (PCT) immunochromatography in vitro diagnostic reagents

Cardiovascular and cerebrovascular diseases represent the leading causes of mortality among middle-aged and elderly populations in China, with inflammation identified as a significant contributing factor. Consequently, the early diagnosis and management of inflammation are of paramount importance. C-reactive protein (CRP) and procalcitonin (PCT) serve as biomarkers for myocardial inflammation. In this study, we developed a quantum dot immunochromatographic strip that was capable of simultaneously detecting these two biomarkers with enhanced sensitivity and specificity. The comb amphiphilic poly (octadecyl-alt-polyethylene glycol) was synthesized through an amide reaction, which was employed to coat oil-soluble quantum dots, thereby transforming them into water-soluble quantum dots microbeads suitable for the coupling with biological macromolecules. These quantum dots microbeads were utilized as luminescent materials in the immunochromatographic strip for the concurrent detection of CRP and PCT. The assay required only 100 μL of sample and provided results within 10 min, demonstrating commendable precision, stability, sensitivity, and accuracy. Clinical evaluations confirmed that the developed CRP and PCT quantum dots immunochromatographic test strips were accurate and reliable, underscoring their significant potential for practical routine clinical application in the early accurate diagnosis of myocardial inflammation.

Evaluation of utilization and consequences of CRP point-of-care-testing in primary care practices: qualitative interviews with general practitioners from Germany.

The use and advantages of point-of-care tests (POCTs) for C-reactive protein (CRP) in general practice, especially for upper respiratory tract infections (uRTIs), have been studied extensively. However, there is limited knowledge about test indications, prerequisites, and integration of these tests into everyday practice. This study aims to investigate the attitudes and experiences of general practitioners (GPs) in Germany regarding the use of semi-quantitative CRP-POCTs. The study places special emphasis on implementation in routine care, including testing procedures, feasibility, opportunities and barriers for specific consultation scenarios, as well as test indications and their impact on GP-patient communication. Qualitative interview study with 10 GPs (May/2023 to Aug/2023) METHOD: Ten German GPs who participated in an observational study on CRP-POCT use in general practices were interviewed using semi-structured interviews. Audio recordings were transcribed and content analysis was performed. Interviewed GPs stated that CRP-POCTs offer several advantages for various treatment cases. They improve diagnostic confidence and certainty of GPs' therapeutic decisions, and offer a broad spectrum of indications and application scenarios. Additionally, they have a positive impact on GP-patient communication, and their ease of use enables rapid implementation into existing workflows. On the other hand, CRP-POCT increase the time required for test performance and patient consultation. Due to the numerous benefits of semi-quantitative CRP-POCTs, interviewed GPs have a favourable attitude towards their regular integration into everyday practice. Implementation barriers include increased time and personnel expenses for testing and inadequate reimbursement by German statutory health insurance.

Unnecessary repetitions of C-reactive protein and leukocyte count at the emergency department observation unit contribute to higher hospital admission rates.

The aim of the present study was to assess the effect of repeated laboratory measurement of C-reactive protein (CRP) and leukocyte count on the decision whether to admit or dicharge the patient with localized infections who received antibiotics at the Emergency Department (ED) observation unit. Adult patients with respiratory, urinary tract and abdominal infections, observed at the ED after antibiotic administration, in whom repeated measurements of CRP and leukocyte count were performed within 24 h, were included. They were initially grouped as planned discharge, planned admission and unclear attitude towards admission. Initial and repeated CRP and leukocyte count results, clinical dynamics (improvement, worsening, unchanged) and clinical decision about discharge or admission, were recorded. A total of 1,038 patients were eligible for inclusion. No significant differences in initial CRP and leukocyte count values were observed, nor any association of CRP and leukocyte count changes with clinical dynamics. Among 504 patients eligible for discharge at second laboratory sampling according to clinical dynamics, 54.4 % were further observed or admitted. Discharged patients had an average negative absolute (p<0.001) and relative CRP change (p=0.002). Clinical dynamics, first and second CRP results and absolute CRP change were independently associated with the decision to discharge or further observe/admit. Schematic repetitions of CRP and leukocyte count at the ED observation unit are common, regardless of patients' clinical condition. Clinical judgment remains the main guiding factor to admit or discharge the patient, but repeated CRP testing influences the final decision, contributing to higher admission rates.

Effect of Combination of Point-of-Care C-Reactive Protein Testing and General Practitioner Education and Long-Term Effect of Education on Reducing Antibiotic Prescribing for Children Presenting with Acute Infections in General Practice in Latvia: A Randomized Controlled Intervention Study.

Antibiotics are often overprescribed in children in general practice. We investigated whether the availability of C-reactive protein point-of-care testing (CRP POCT) in daily practice and general practitioner (GP) education reduces antibiotic prescribing for children with acute infections and whether GP education has a long-term effect on antibiotic prescribing. This was a randomized controlled intervention study with randomization at the GP practice level. Eligible patients were children aged 1 month to 17 years presenting to general practice with an acute infection. In the first study period, one GP group received combined interventions (CRP POCT was provided for daily use in combination with a live educational session), while the second GP group continued usual care. During the second study period, the GP groups were switched. During this period, the long-term education effect was evaluated in the GP group, which had previously received both interventions: the CRP POCT was no longer available in their practices in accordance with the study protocol, but education could have a lasting effect. Antibiotic prescribing at index consultation. GP with combined intervention enrolled 1784 patients, GP with usual care enrolled 886 patients, and GP with long-term education effect enrolled 647 patients. Most of the patients had upper (76.8%) and lower (18.8%) respiratory infections. In total, 29.3% of the study patients received antibiotic prescriptions. Adjusted binary logistic regression analysis showed no differences for the primary outcome between GPs with usual care and GPs with combined intervention (aOR 0.89 (0.74-1.07), p = 0.20), but significantly lower antibiotic prescribing was observed for GPs with long-term education in comparison with GPs with usual care (aOR 0.75 (0.59-0.96), p = 0.02); however, after multilevel analyses, any differences in the antibiotic prescription between intervention groups became non-significant. GPs widely used CRP POCT when it was available in practice (for 69.1% of patients in the combined intervention group), but rarely measured CRP in the laboratory in the usual care group (8.8% (n = 78)) or long-term education group (14.8% (n = 98)). The majority of the tested patients had low CRP levels (below 20 mg/L); despite this, up to 35.4% of them received antibiotic prescriptions. Our results show that the availability of CRP POCT and educational training for GPs together did not reduce antibiotic prescribing, and one-time education did not have a long-term effect on antibiotic prescribing.

C-reactive protein testing in primary care for acute respiratory infections: a cost-effective strategy to mitigate antimicrobial resistance across different income settings

C-reactive protein testing in primary care for acute respiratory infections: a cost-effective strategy to mitigate antimicrobial resistance across different income settings

Systemic inflammation and health outcomes in patients receiving treatment for atherosclerotic cardiovascular disease.

The burden and outcomes of inflammation in patients with atherosclerotic cardiovascular disease (ASCVD) are not well defined beyond the controlled settings of trials and research cohorts. This was an observational study of ASCVD adults undergoing C-reactive protein testing in Stockholm's healthcare (2007-21). After excluding C-reactive protein tests associated with acute illness or medications/conditions that bias C-reactive protein interpretation, systemic inflammation was evaluated over a 3-month ascertainment window. Determinants of C-reactive protein ≥ 2 mg/L were explored with logistic regression. C-reactive protein categories were compared via negative-binomial/Cox regression for subsequent healthcare resource utilization and occurrence of major adverse cardiovascular events, heart failure hospitalization, and death. A total of 84 399 ASCVD adults were included (46% female, mean age 71 years, 59% with C-reactive protein ≥ 2 mg/L). Female sex, older age, lower kidney function, albuminuria, diabetes, hypertension, and recent anaemia were associated with higher odds of C-reactive protein ≥ 2 mg/L. The use of renin-angiotensin system inhibitors, antiplatelets, and lipid-lowering therapy was associated with lower odds. Over a median of 6.4 years, compared with C-reactive protein < 2 mg/L, patients with C-reactive protein ≥ 2 mg/L had higher rates of hospitalizations, days spent in hospital, outpatient consultations, and dispensed medications (P < .05 for all). They also had a higher rate of major adverse cardiovascular events [hazard ratio (HR) 1.30; 95% confidence interval (CI) 1.27-1.33], heart failure (HR 1.24; 95% CI 1.20-1.30), and death (HR 1.35; 95% CI 1.31-1.39). Results were consistent across subgroups and granular C-reactive protein categories and robust to the exclusion of extreme C-reactive protein values or early events. Three in five adults with ASCVD have systemic inflammation, which is associated with excess healthcare resource utilization and increased rates of cardiovascular events and death.

Combining PCT with CRP is better than separate testing for patients with bacteriuria in the intensive care unit: a retrospective study

BackgroundPrevious studies on PCT for urinary tract infections (UTI) have focused primarily on minors. This study investigated the predictive value of the neutrophil-to-lymphocyte ratio (NLR), C-reactive protein (CRP) level and procalcitonin (PCT) level in adult patients with bacteriuria in IUC.MethodsThis case‒control study included 85 patients with bacteriuria (PB) in the ICU from March 2021 to Jan 2024 based on positive urine culture results and a control group (n = 136) from Jan 2024 to March 2024. Patient data were collected using a hospital information management system. ROC curves of the NLR, CRP and PCT were use to predict the PB.ResultsThe AUCs of the NLR, CRP and PCT for the prediction of PB in ICU were 0.711 (95% CI 0.644–0.772), 0.855 (95% CI 0.800–0.900), and 0.884 (95% CI 0.832–0.924), respectively; the optimal thresholds were 8.02, 18.52 mg/L, and 0.215 ng/mL, respectively; the sensitivities were 69.0 (95% CI 56.9–79.5), 90.1 (95% CI 80.7–95.9), and 83.1 (95% CI 72.3–91.0), respectively; and the specificities were 67.6 (95% CI 59.1–75.4), 68.4 (95% CI 59.9–76.1), and 80.9 (95% CI 73.3–87.1), respectively. The negative predictive value (NPV) of CRP is greater than that of PCT. In bacteriuria caused by Candida infections, CRP and PCT have higher sensitivity and NPV.ConclusionsCombined CRP and PCT testing is more helpful for diagnosing bacteriuria. CRP and PCT have higher sensitivity and NPV in diagnosing bacteriuria caused by Candida infection.

Utilization and consequences of CRP point-of-care-testing in primary care practices: a real-world multicentre observational study with 1,740 patient cases in Germany.

Point-of-care tests (POCTs) for C-reactive protein can support clinical decision-making of general practitioners (GPs) but are not widely used in German general practices. To investigate the utilization of semi-quantitative CRP-POCTs in routine primary care. Prospective observational study in 49 general practices in Germany (Nov/2022 to Apr/2023). GPs were provided with CRP-POCTs and collected data for each CRP-POCT use using standardized data collection sheets. Data from 1,740 CRP-POCT uses were recorded. GPs employed CRP-POCTs mainly for patients with respiratory tract infections (RTIs, 70.9% of all cases) and to a lesser extent for gastrointestinal infections (GIs, 10.3%). In RTIs, CRP-POCTs were frequently used to distinguish between bacterial and viral aetiology (60.8%) and to guide decisions on antibiotic prescribing (62.8%). In GIs, CRP-POCTs were mainly used to rule out severe disease progressions (53.2%) and for decisions on further diagnostic procedures (45.6%). In RTIs, CRP-POCTs influenced antibiotic prescribing in 77.5 % of the cases (32.3% in favour vs. 45.2% waiver). In GIs, CRP levels mainly affected decisions on further diagnostic procedures. GPs reported that CRP-POCTs were helpful in 88.6% of all cases. When available, German GPs predominantly use semi-quantitative CRP-POCTs to guide decisions on antibiotic prescribing in patients with RTI. CRP-POCT use improves clinical decision-making and increases the GPs' clinical confidence.

The impact of national guidelines on the diagnostics of sore throat in children

BackgroundThe Finnish treatment guidelines for sore throat were updated in June 2020. The aim of this study was to determine how the publication of these guidelines affected the treatment of pediatric patients, particularly through the use of the Centor criteria, C-reactive protein tests, and microbiological testing in the diagnosis of Group A β-hemolytic streptococci tonsillitis.MethodsWe conducted a retrospective single-center before-and-after cohort study in Finland from 2019 to 2022. We included all patients who visited the pediatric emergency department and were diagnosed with tonsillitis or pharyngitis.ResultsWe included 246 patients who were admitted before the guidelines were updated and 219 patients after. Only two patients in the after group had a Centor score reported in their patient records. Rapid antigen tests were administered to 231 patients (93.9%) before the update and 202 patients (92.2%) after (proportion difference of 1.7%, CI -3.0–6.6%). C-reactive protein was taken from 193 patients (78.5%) before the update and 189 patients (86.3%) after (proportion difference of 7.8%, CI 0.1–14.7%).ConclusionsCentor scores were not used as recommended in the guidelines and did not impact the use of microbiological or C-reactive protein testing. More education and examining the preconceptions of health care personnel is required to implement the updated treatment guidelines in clinical practice.

Ferritin Cutoffs and Diagnosis of Iron Deficiency in Primary Care

Ferritin is often measured by general practitioners, but the association of different cutoffs with the rates of iron deficiency diagnoses, particularly nonanemic iron deficiency, is unknown. To investigate the association of the ferritin cutoff choice with the incidence of nonanemic and anemic iron deficiency diagnoses in primary care. In this retrospective cohort study, patients 18 years or older with at least 1 consultation with a general practitioner participating in the Family Medicine Research Using Electronic Medical Records (FIRE) project, an electronic medical records database of Swiss primary care, from January 1, 2021, to November 30, 2023, were evaluated. Sex, age, clinical patient characteristics, and professional general practitioner characteristics. Incidence of iron deficiency diagnoses (nonanemic and anemic) at ferritin cutoffs of 15, 30, and 45 ng/mL and ferritin testing itself. Time-dependent Cox proportional hazards regression was used to examine associations of patient and general practitioner characteristics with ferritin testing as adjusted hazard ratios (AHRs). The study included 255 351 patients (median [IQR] age, 52 [36-66] years; 52.1% female). Per 1000 patient-years and at ferritin cutoffs of 15, 30, and 45 ng/mL, iron deficiency diagnoses had incidences of 10.9 (95% CI, 10.6-11.2), 29.9 (95% CI, 29.4-30.4), and 48.3 (95% CI, 47.7-48.9) cases, respectively; nonanemic iron deficiency diagnoses had incidences of 4.1 (95% CI, 3.9-4.2), 14.6 (95% CI, 14.3-15.0), and 25.8 (95% CI, 25.3-26.2) cases, respectively; and anemic iron deficiency diagnoses had incidences of 3.5 (95% CI, 3.3-3.7), 6.0 (95% CI, 5.8-6.2), and 7.5 (95% CI, 7.3-7.7) cases, respectively. Ferritin testing showed notable associations with fatigue (AHR, 2.03; 95% CI, 1.95-2.12), anemia (AHR, 1.75; 95% CI, 1.70-1.79), and iron therapy (AHR, 1.50; 95% CI, 1.46-1.54). Ferritin testing was associated with female sex in all age groups, including postmenopausal. Of the patients who received ferritin testing, 72.1% received concomitant hemoglobin testing, and 49.6% received concomitant C-reactive protein testing. In this retrospective cohort study of primary care patients, ferritin cutoffs of 30 and 45 ng/mL were associated with a substantially higher incidence of iron deficiency compared with 15 ng/mL. These results provide a basis for health system-level evaluation and benchmarking of ferritin testing in high-resource settings and call for a harmonization of diagnostic criteria for iron deficiency in primary care.

Reducing Erythrocyte Sedimentation Rate Ordering: De-implementation and Diagnostic Stewardship.

The Choosing Wisely campaign recommends against the routine use of erythrocyte sedimentation rate (ESR) for the assessment of acute undiagnosed inflammation or infection. We examined ESR and C-reactive protein (CRP) ordering practices at a large, freestanding children's hospital. We found that 80% of ESR orders were placed concurrently with a CRP order. We aimed to reduce the ESR testing rate by 20% within 6 months in both inpatient and emergency department (ED) settings. Applying Lean process improvement principles, we interviewed stakeholders from multiple subspecialties and engaged the institutional laboratory stewardship committee to identify the root causes of ESR ordering and design interventions. We conducted provider education (November 2020) and employed clinical decision support through an order panel in the electronic health record (April 2021). The outcome measures were monthly ESR testing rate per 1000 patient days (inpatient) and per 1000 ED visits, analyzed using statistical process control charts. CRP testing rate was a balancing measure. After intervention implementation, the ESR testing rate decreased from 11.4 to 8.9 tests per 1000 inpatient patient days (22% decrease) and from 49.4 to 29.5 tests per 1000 ED visits (40% decrease). This change has been sustained for >1 year postintervention. Interventions were effective even during the coronavirus disease 2019 pandemic when there was a rise in baseline ED ESR ordering rate. CRP testing rates did not increase after the interventions. Education and clinical decision support were effective in reducing the ESR ordering rate in both inpatient and ED settings.

Potential Utility of C-reactive Protein for Tuberculosis Risk Stratification Among Patients With Non-Meningitic Symptoms at HIV Diagnosis in Low- and Middle-income Countries.

The World Health Organization recommends initiating same-day antiretroviral therapy (ART) while tuberculosis (TB) testing is under way for patients with non-meningitic symptoms at HIV diagnosis, though safety data are limited. C-reactive protein (CRP) testing may improve TB risk stratification in this population. In this baseline analysis of 498 adults (>18 years) with TB symptoms at HIV diagnosis who were enrolled in a trial of rapid ART initiation in Haiti, we describe test characteristics of varying CRP thresholds in the diagnosis of TB. We also assessed predictors of high CRP as a continuous variable using generalized linear models. Eighty-seven (17.5%) participants were diagnosed with baseline TB. The median CRP was 33.0 mg/L (interquartile range: 5.1, 85.5) in those with TB, and 2.6 mg/L (interquartile range: 0.8, 11.7) in those without TB. As the CRP threshold increased from ≥1 mg/L to ≥10 mg/L, the positive predictive value for TB increased from 22.4% to 35.4% and negative predictive value decreased from 96.9% to 92.3%. With CRP thresholds varying from <1 to <10 mg/L, a range from 25.5% to 64.9% of the cohort would have been eligible for same-day ART and 0.8% to 5.0% would have untreated TB at ART initiation. CRP concentrations can be used to improve TB risk stratification, facilitating same-day decisions about ART initiation. Depending on the CRP threshold, one-quarter to two-thirds of patients could be eligible for same-day ART, with a reduction of 3- to 20-fold in the proportion with untreated TB, compared with a strategy of same-day ART while awaiting TB test results.