White blood cells, C-reactive protein and erythrocyte sedimentation rate in pneumococcal pneumonia in children

Risk factors of severe Chlamydia trachomatis pneumonia in children: a retrospective case-control study

This study explored the clinical characteristics of Chlamydia trachomatis (C. trachomatis) pneumonia in children and the risk factors for severe C. trachomatis pneumonia. This retrospective case-control study included children with C. trachomatis pneumonia who were admitted to the Department of Pediatrics, Women and Children's Hospital, School of Medicine, Xiamen University (Xiamen, China) between January 2018 and December 2021. Among 117 children, 33 (28.2%) had severe C. trachomatis pneumonia and 84 children had mild-to-moderate C. trachomatis pneumonia. According to the results of the binary logistic regression analysis, congenital heart disease [odds ratio (OR) = 0.09, 95% confidence interval (CI): 0.01-0.74, P-value = .024], mixed infection (OR = 0.17, 95%CI: 0.05-0.51, P-value = .002), white blood cell count greater than 15 000 cells/dl (OR = 1.20, 95%CI: 1.03-1.40, P-value = .022), and partial pressure of carbon dioxide (PaCO2) (OR = 1.14, 95%CI: 1.02-1.26, P-value = .016) were found as independent predictive factors for severe C. trachomatis pneumonia in children. This study explored key risk factors for severe C. trachomatis pneumonia, a condition underreported in tropical regions where pediatric respiratory infections are a leading cause of morbidity and mortality. By identifying risk factors, such as congenital heart disease, mixed infections, and elevated PaCO2, this research may guide early intervention strategies in resource-limited settings, potentially reducing pediatric pneumonia deaths.

Community-Acquired Pneumonia in Children

ABSTRACT

Community-acquired pneumonia (CAP) is the most common cause of childhood mortality globally. In the United States, CAP is a leading cause of pediatric hospitalization and antibiotic use and is associated with substantial morbidity. There has been a dramatic shift in microbiological etiologies for CAP in children over time as pneumococcal pneumonia has become less common and viral etiologies have become predominant. There is no commonly agreed on approach to the diagnosis of CAP in children. When indicated, antimicrobial treatment should consist of narrow-spectrum antibiotics. In this article, we will describe the current understanding of the microbiological etiologies, clinical presentation, diagnostic approach, risk factors, treatment, and future directions in the diagnosis and management of pediatric CAP.

Preparing of Point-of-Care Reagents for Risk Assessment in the Elderly at Home by a Home-Visit Nurse and Verification of Their Analytical Accuracy

With the rising number of older adults residing at home, there is a growing need for risk assessment and patient management in home nursing. This study aims to develop point-of-care test (POCT) reagents that can aid in risk assessment and home care, especially in settings with limited resources. Our focus was on creating a C-reactive protein (CRP) POCT, which can accurately diagnose clinically significant judgment values in home nursing. Additionally, we assessed the utility of the HemoCue WBC DIFF system in providing differential counts of white blood cells (WBC). These performances were compared with a laboratory test using blood samples from patients with pneumonia. The CRP POCT showed a comparable result to that of a laboratory method, with an average kappa index of 0.883. The leukocyte count showed good agreement with the reference method. While the correlation coefficients for both neutrophil and lymphocyte counts were deemed acceptable, it was observed that the measured values tended to be smaller in cases where the cell count was higher. This proportional error indicates a weak correlation with the neutrophil-to-lymphocyte ratio. CRP POCT and WBC counts provided reliable and accurate judgments. These tools may benefit risk management for older adults at home, patients with dementia who cannot communicate, and those living in depopulated areas.

Tomography and Prognostic Indices in the State of the Art of Evaluation in Hospitalized Patients with COVID-19 Pneumonia

Evaluation in medical emergencies of COVID-19 patients represents a challenge to regulate preventive and timely management. There are key imaging and laboratory tools to classify the severity. The aim of the study was to evaluate the chest CT score performance and prognostic indices in COVID-19 patients to predict the progression to critical illness. This was a retrospective study between run between April and December 2020, in which 109 patients were included. Patients of any age and gender and who required hospitalization due to a confirmed COVID-19 diagnosis by RT-PCR and chest CT and laboratory were analyzed. In 75% of them, there was at least one comorbidity, and 30% developed critical illness, and the average mortality was 10%. In 49.5%, there was a CORADS-5 on admission, and in 50%, there was a peripheral distribution of the interstitial infiltrate in the left lower lobe. The risk factors were FiO2, CT score > 18, and the NRL index. The combination of the high-risk Quick COVID-19 Severity Index (qCSI) plus CT score > 18 indices was the best prediction index for the development of a critical condition. The combined use of indices in infected COVID-19 patients showed diagnostic accuracy and predicted severity. Imaging and the laboratory tests are key tools independent of the wave of recurrence.

Clinical impact of rapid viral respiratory panel testing on pediatric critical care of patients with acute lower respiratory infection

BACKGROUND

We aimed to determine the impact of utilizing a rapid panel test of respiratory viral and atypical bacteria (FilmArray® Respiratory Panel, FA RP) on etiological diagnosis of acute lower respiratory infection (ALRI) and antimicrobial stewardship in critical care pediatric patients.

METHODS

Prospective cohort study of patients aged<18 years with clinical diagnosis of ALRI that were admitted to the Pediatric Intensive Care Unit (PICU) of Hospital Sant Joan de Deu (Barcelona, Spain) during December 2015-February 2017. Patients were diagnosed by FA RP and by a bundle of routine microbiological assays.

RESULTS

ALRI viral and bacterial etiology was confirmed by a composite reference standard of routine microbiological assays in 72 (55.4%) and 15 (11.5%) respiratory samples, respectively, that were collected from 130 children (median age, 3.5 months, IQR 1.1-14.8 months; 54.6% male). Comparatively, FA RP use increased etiological confirmation of ALRI in up to 123 (94.6%) samples (p<0.001) but only determined a bacterial origin in 2 (1.5%). Availability of diagnostic results before patient discharge from the PICU rose from 65.4 to 38.5% (p<0.001). Use of the new panel test directly influenced antimicrobial stewardship in 11 (8.4%) episodes, leading to discontinuation of antiviral drugs (n=5), administration of targeted antibiotics (n=3), antiviral therapy start (n=2) and both targeted antibiotic administration and discontinuation of antiviral drugs (n=1).

CONCLUSION

FA RP contributed to improve etiological diagnosis of ALRI in a timely manner while enhancing a more rational use of antimicrobial drugs in critical care pediatric patients.

Role of lung ultrasound for the etiological diagnosis of acute lower respiratory tract infection (ALRTI) in children: a prospective study

Objective and design

Our prospective study assesses the role of detailed lung ultrasound (LUS) features to discriminate the etiological diagnosis of acute lower respiratory tract infection (ALRTI) in children.

Methodology

We analyzed patients aged from 1 month to 17 years admitted between March 2018 and April 2020 who were hospitalized for ALRTI. For all patients, history, clinical parameters, microbiological data, and lung ultrasound data were collected. Patients were stratified into three main groups (“bacterial”, “viral”, “atypical”) according to the presumed microbial etiology and LUS findings evaluated according to the etiological group. Nasopharyngeal swabs were obtained from all patients. A qualitative diagnostic test developed by Nurex S.r.l. was used for identification of bacterial and fungal DNA in respiratory samples. The Seegene Allplex™ Respiratory assays were used for the molecular diagnosis of viral respiratory pathogens. In addition, bacterial culture of blood and respiratory samples were performed, when indicated.

Results

A total of 186 children with suspected ALRTI (44% female) with an average age of 6 were enrolled in the study. We found that some ultrasound findings as size, number and distribution of consolidations, the position and motion of air bronchograms, pleural effusions and distribution of vertical artifacts significantly differ (p < 0.05) in children with bacterial, viral and atypical ALRTI.

Conclusion

Our study provides a detailed analysis of LUS features able to predict the ALRTI ethology in children. These findings may help the physicians to better manage a child with ALRTI and to offer personalized approach, from diagnosis to treatment and follow-up.

The effect of C-reactive protein on chest X-ray interpretation: A decision-making experiment among pediatricians

INTRODUCTION

Clinical decision-making is complex and requires the integration of multiple sources of information. Physicians tend to over-rely on objective measures, despite the lack of supportive evidence in many cases. We sought to test if pediatricians over-rely on C-reactive protein (CRP) results when managing a child with suspected pneumonia.

METHODS

A nationwide decision-making experiment was conducted among 337 pediatricians in Israel. Each participant was presented with two detailed vignettes of a child with suspected pneumonia, each with a chest X-ray (CXR) taken from a real-life case of viral pneumonia. Participants were randomly assigned to one of three groups: Controls-where no lab tests were provided, and two intervention groups where the vignettes also noted a high or a low CRP value, in varying orders. Between-participant and within-participant analyses were conducted to study the effect of CRP on CXR interpretation. The three groups were presented with identical medical history, vital signs, findings on physical examination, blood count, and CXR.

RESULTS

Three-hundred and one pediatricians (89.3% of those approached) completed the study. Pediatricians were 60%-90% more likely to diagnose viral pneumonia as bacterial when presented with high CRP levels versus low CRP levels, despite the identical clinical data and CXR (62% vs. 39% and 58% vs. 31% of physicians; p = .002). Accordingly, they were 60%-90% more likely to prescribe antibiotics in these cases (86% vs. 53% and 78% vs. 41% of physicians; p < .001).

CONCLUSIONS

CRP by itself may modify the way in which pediatricians interpret a CXR, leading to the overprescription of antibiotics.

VB10, a new blood biomarker for differential diagnosis and recovery monitoring of acute viral and bacterial infections

BACKGROUND

Precise differential diagnosis between acute viral and bacterial infections is important to enable appropriate therapy, avoid unnecessary antibiotic prescriptions and optimize the use of hospital resources. A systems view of host response to infections provides opportunities for discovering sensitive and robust molecular diagnostics.

METHODS

We combine blood transcriptomes from six independent datasets (n = 756) with a knowledge-based human protein-protein interaction network, identifies subnetworks capturing host response to each infection class, and derives common response cores separately for viral and bacterial infections. We subject the subnetworks to a series of computational filters to identify a parsimonious gene panel and a standalone diagnostic score that can be applied to individual samples. We rigorously validate the panel and the diagnostic score in a wide range of publicly available datasets and in a newly developed Bangalore-Viral Bacterial (BL-VB) cohort.

FINDING

We discover a 10-gene blood-based biomarker panel (Panel-VB) that demonstrates high predictive performance to distinguish viral from bacterial infections, with a weighted mean AUROC of 0.97 (95% CI: 0.96-0.99) in eleven independent datasets (n = 898). We devise a new stand-alone patient-wise score (VB10) based on the panel, which shows high diagnostic accuracy with a weighted mean AUROC of 0.94 (95% CI 0.91-0.98) in 2996 patient samples from 56 public datasets from 19 different countries. Further, we evaluate VB10 in a newly generated South Indian (BL-VB, n = 56) cohort and find 97% accuracy in the confirmed cases of viral and bacterial infections. We find that VB10 is (a) capable of accurately identifying the infection class in culture-negative indeterminate cases, (b) reflects recovery status, and (c) is applicable across different age groups, covering a wide spectrum of acute bacterial and viral infections, including uncharacterized pathogens. We tested our VB10 score on publicly available COVID-19 data and find that our score detected viral infection in patient samples.

INTERPRETATION

Our results point to the promise of VB10 as a diagnostic test for precise diagnosis of acute infections and monitoring recovery status. We expect that it will provide clinical decision support for antibiotic prescriptions and thereby aid in antibiotic stewardship efforts.

FUNDING

Grand Challenges India, Biotechnology Industry Research Assistance Council (BIRAC), Department of Biotechnology, Govt. of India.

Preconceptional and prenatal exposure to air pollution increases incidence of childhood pneumonia: A hypothesis of the (pre-)fetal origin of childhood pneumonia

BACKGROUND

Increasing evidence has linked childhood pneumonia with early exposure to ambient air pollution. However, the impact of exposure to air pollutants before birth is unclear.

OBJECTIVE

To further clarify whether exposure to a particular pollutant during preconceptional and prenatal periods, may pose a higher risk of developing childhood pneumonia.

METHODS

This case-control cohort study consisted of 1510 children aged 0-14 years in Changsha, China between 2017 and 2019. Data of children's history of pneumonia and blood biomarkers were obtained from the XiangYa Hospital records. Each child's exposure to air pollutants, including nitrogen dioxide (NO₂), sulfur dioxide (SO₂), and particulate matter with an aerodynamic diameter ≤ 10 µm (PM₁₀), was calculated using data from ten air pollution monitoring stations. A multivariate logistic regression model was used to quantify the relationship between childhood pneumonia and exposure to ambient air pollution during the preconceptional and prenatal periods.

RESULTS

Childhood pneumonia was significantly associated with preconceptional and prenatal exposure to the industrial-related air pollutant, SO₂, for 1 year before conception, for 3 months before conception and for the entire pregnancy, with ORs(95% CI)= 4.01(3.17-5.07), 4.06(3.29-5.00) and 6.51(4.82-8.79). Also, children who were sick with pneumonia had higher white blood cell and neutrophil counts, and children with low eosinophil count or hemoglobin are likely to get pneumonia. Sensitivity analysis showed that boys, and children in high temperature area were susceptible to the effect of both preconceptional and prenatal exposure to industrial SO₂.

CONCLUSION

Preconceptional and prenatal exposure to industrial-related air pollution plays a significant role in the incidence and progression of childhood pneumonia, supporting the hypothesis of "(pre-)fetal origin of childhood pneumonia".

Clinical impact of rapid viral respiratory panel testing on pediatric critical care of patients with acute lower respiratory infection

BACKGROUND

We aimed to determine the impact of utilizing a rapid panel test of respiratory viral and atypical bacteria (FilmArray® Respiratory Panel, FA RP) on etiological diagnosis of acute lower respiratory infection (ALRI) and antimicrobial stewardship in critical care pediatric patients.

METHODS

Prospective cohort study of patients aged<18 years with clinical diagnosis of ALRI that were admitted to the Pediatric Intensive Care Unit (PICU) of Hospital Sant Joan de Deu (Barcelona, Spain) during December 2015-February 2017. Patients were diagnosed by FA RP and by a bundle of routine microbiological assays.

RESULTS

ALRI viral and bacterial etiology was confirmed by a composite reference standard of routine microbiological assays in 72 (55.4%) and 15 (11.5%) respiratory samples, respectively, that were collected from 130 children (median age, 3.5 months, IQR 1.1-14.8 months; 54.6% male). Comparatively, FA RP use increased etiological confirmation of ALRI in up to 123 (94.6%) samples (p<0.001) but only determined a bacterial origin in 2 (1.5%). Availability of diagnostic results before patient discharge from the PICU rose from 65.4 to 38.5% (p<0.001). Use of the new panel test directly influenced antimicrobial stewardship in 11 (8.4%) episodes, leading to discontinuation of antiviral drugs (n=5), administration of targeted antibiotics (n=3), antiviral therapy start (n=2) and both targeted antibiotic administration and discontinuation of antiviral drugs (n=1).

CONCLUSION

FA RP contributed to improve etiological diagnosis of ALRI in a timely manner while enhancing a more rational use of antimicrobial drugs in critical care pediatric patients.

Evaluating the Usefulness of Lab-Based Test for the Diagnosis of Pneumonia in Children

Objective

The aim of this study is to determine the distribution of the results of routine laboratory tests for the diagnosis of pneumonia in children in Khorramabad.

Methods

This is a cross-sectional study and was performed on 650 children with pneumonia who were referred to Shahid Madani Hospital. From patients' test results, the following data were recorded: whether the results were normal or not, age, sex, serotype, history of diabetes mellitus, and the presence of urinary and digestive tract symptoms.

Results

There was no difference in the prevalence of pneumonia, gender-wise, whereas 40% of the patients were under 2 years. In addition, 53.7% of the patients were presented with leukocytosis. From the blood test, blood urea nitrogen, creatinine, sodium, and potassium were normal in most of the patients. Stool examination, urine analysis, urine culture, erythrocyte sedimentation rate, C-reactive protein, and blood sugar were also normal in these patients.

Conclusion

Children under the age of 2 years are more susceptible to lung infections. Findings from blood tests such as leukocytosis are useful for making initial diagnosis other than computed tomography scan. Other lab tests might not give any useful results. In addition, a closer examination of the urinary system and digestive tract involvement is recommended, prior to urine or stool analysis.

Sensitivity of C-reactive protein for the identification of patients with laboratory-confirmed bacterial infections in northern Tanzania

OBJECTIVE

Identifying febrile patients requiring antibacterial treatment is challenging, particularly in low-resource settings. In South-East Asia, C-reactive protein (CRP) has been demonstrated to be highly sensitive and moderately specific in detecting bacterial infections and to safely reduce unnecessary antibacterial prescriptions in primary care. As evidence is scant in sub-Saharan Africa, we assessed the sensitivity of CRP in identifying serious bacterial infections in Tanzania.

METHODS

Samples were obtained from inpatients and outpatients in a prospective febrile illness study at two hospitals in Moshi, Tanzania, 2011-2014. Bacterial bloodstream infections (BSI) were established by blood culture, and bacterial zoonotic infections were defined by ≥4 fold rise in antibody titre between acute and convalescent sera. The sensitivity of CRP in identifying bacterial infections was estimated using thresholds of 10, 20 and 40 mg/l. Specificity was not assessed because determining false-positive CRP results was limited by the lack of diagnostic testing to confirm non-bacterial aetiologies and because ascertaining true-negative cases was limited by the imperfect sensitivity of the diagnostic tests used to identify bacterial infections.

RESULTS

Among 235 febrile outpatients and 569 febrile inpatients evaluated, 31 (3.9%) had a bacterial BSI and 61 (7.6%) had a bacterial zoonosis. Median (interquartile range) CRP values were 173 (80-315) mg/l in bacterial BSI, and 108 (31-208) mg/l in bacterial zoonoses. The sensitivity (95% confidence intervals) of CRP was 97% (83%-99%), 94% (79%-98%) and 90% (74%-97%) for identifying bacterial BSI, and 87% (76%-93%), 82% (71%-90%) and 72% (60%-82%) for bacterial zoonoses, using thresholds of 10, 20 and 40 mg/l, respectively.

CONCLUSION

C-reactive protein was moderately sensitive for bacterial zoonoses and highly sensitive for identifying BSIs. Based on these results, operational studies are warranted to assess the safety and clinical utility of CRP for the management of non-malaria febrile illness at first-level health facilities in sub-Saharan Africa.

Erythrocyte Sedimentation Rate and C-Reactive Protein in Acute Inflammation

OBJECTIVES

To assess the diagnostic accuracy of erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) in acute inflammation.

METHODS

PubMed and Scopus were searched and eligible articles were screened for methodologic quality using the Quality Assessment of the Diagnostic Accuracy Studies-Revised. Meta-analysis with calculation of pooled sensitivity (Se), specificity (Sp), and summary area under the curve (SAUC) was performed.

RESULTS

Twenty-nine studies were eligible. Se and Sp were 0.78 and 0.68 (SAUC = 0.80) for ESR in orthopedic infections and 0.79 and 0.70 (SAUC = 0.81) for CRP. For the diagnosis of other various inflammatory conditions, CRP had a superior diagnostic accuracy, with a Se of 0.86, Sp of 0.67, and SAUC of 0.86 compared with a Se of 0.77, Sp of 0.59, and SAUC of 0.75 for ESR. Heterogeneity among studies was elevated. Combined use of ESR and CRP yielded higher diagnostic accuracy.

CONCLUSIONS

Despite observed heterogeneity among studies, ESR and CRP have a similar diagnostic accuracy in assessment of inflammation, especially in orthopedic conditions.

Combination of clinical symptoms and blood biomarkers can improve discrimination between bacterial or viral community-acquired pneumonia in children

BACKGROUND

Differentiating bacterial from viral pneumonia is important for guiding targeted management and judicious use of antibiotics. We assessed if clinical characteristics and blood inflammatory biomarkers could be used to distinguish bacterial from viral pneumonia.

METHODS

Western Australian children (≤17 years) hospitalized with radiologically-confirmed community-acquired pneumonia were recruited and clinical symptoms and management data were collected. C-reactive protein (CRP), white cell counts (WCC) and absolute neutrophil counts (ANC) were measured as part of routine care. Clinical characteristics and biomarker levels were compared between cases with definite bacterial pneumonia (clinical empyema and/or bacteria detected in blood or pleural fluid), presumed viral pneumonia (presence of ≥1 virus in nasopharyngeal swab without criteria for definite bacterial pneumonia), and other pneumonia cases (pneumonia in the absence of criteria for either definite bacterial or presumed viral pneumonia). The area-under-curve (AUC) of the receiver operating characteristic (ROC) curve for varying biomarker levels were used to characterise their utility for discriminating definite bacterial from presumed viral pneumonia. For biomarkers with AUC > 0.8 (fair discriminator), Youden index was measured to determine the optimal cut-off threshold, and sensitivity, specificity, predictive values (positive and negative) were calculated. We investigated whether better discrimination could be achieved by combining biomarker values with the presence/absence of symptoms.

RESULTS

From May 2015 to October 2017, 230 pneumonia cases were enrolled: 30 with definite bacterial pneumonia, 118 with presumed viral pneumonia and 82 other pneumonia cases. Differences in clinical signs and symptoms across the groups were noted; more definite bacterial pneumonia cases required intravenous fluid and oxygen supplementation than presumed viral or other pneumonia cases. CRP, WCC and ANC were substantially higher in definite bacterial cases. For a CRP threshold of 72 mg/L, the AUC of ROC was 0.82 for discriminating definite bacterial pneumonia from presumed viral pneumonia. Combining the CRP with either the presence of fever (≥38οC) or the absence of rhinorrhea improved the discrimination.

CONCLUSIONS

Combining elevated CRP with the presence or absence of clinical signs/ symptoms differentiates definite bacterial from presumed viral pneumonia better than CRP alone. Further studies are required to explore combination of biomarkers and symptoms for use as definitive diagnostic tool.

Factors Associated With Pneumonia Severity in Children: A Systematic Review

Community-acquired pneumonia in children is associated with significant morbidity and mortality; however, data are limited in predicting which children will have negative outcomes, including clinical deterioration, severe disease, or development of complications. The Pediatric Infectious Diseases Society/Infectious Diseases Society of America (PIDS/IDSA) pediatric pneumonia guideline includes criteria that were modified from adult criteria and define pneumonia severity to assist with resource allocation and site-of-care decision-making. However, the PIDS/IDSA criteria have not been formally developed or validated in children. Definitions for mild, moderate, and severe pneumonia also vary across the literature, further complicating the development of standardized severity criteria. This systematic review summarizes (1) the current state of the evidence for defining and predicting pneumonia severity in children as well as (2) emerging evidence focused on risk stratification of children with pneumonia.

Association of C-Reactive Protein With Bacterial and Respiratory Syncytial Virus-Associated Pneumonia Among Children Aged <5 Years in the PERCH Study

Background.

Lack of a gold standard for identifying bacterial and viral etiologies of pneumonia has limited evaluation of C-reactive protein (CRP) for identifying bacterial pneumonia. We evaluated the sensitivity and specificity of CRP for identifying bacterial vs respiratory syncytial virus (RSV) pneumonia in the Pneumonia Etiology Research for Child Health (PERCH) multicenter case-control study.

Methods.

We measured serum CRP levels in cases with World Health Organization-defined severe or very severe pneumonia and a subset of community controls. We evaluated the sensitivity and specificity of elevated CRP for "confirmed" bacterial pneumonia (positive blood culture or positive lung aspirate or pleural fluid culture or polymerase chain reaction [PCR]) compared to "RSV pneumonia" (nasopharyngeal/oropharyngeal or induced sputum PCR-positive without confirmed/suspected bacterial pneumonia). Receiver operating characteristic (ROC) curves were constructed to assess the performance of elevated CRP in distinguishing these cases.

Results.

Among 601 human immunodeficiency virus (HIV)-negative tested controls, 3% had CRP ≥40 mg/L. Among 119 HIV-negative cases with confirmed bacterial pneumonia, 77% had CRP ≥40 mg/L compared with 17% of 556 RSV pneumonia cases. The ROC analysis produced an area under the curve of 0.87, indicating very good discrimination; a cut-point of 37.1 mg/L best discriminated confirmed bacterial pneumonia (sensitivity 77%) from RSV pneumonia (specificity 82%). CRP ≥100 mg/L substantially improved specificity over CRP ≥40 mg/L, though at a loss to sensitivity.

Conclusions.

Elevated CRP was positively associated with confirmed bacterial pneumonia and negatively associated with RSV pneumonia in PERCH. CRP may be useful for distinguishing bacterial from RSV-associated pneumonia, although its role in discriminating against other respiratory viral-associated pneumonia needs further study.

A novel host-protein assay outperforms routine parameters for distinguishing between bacterial and viral lower respiratory tract infections

Bacterial and viral lower respiratory tract infections (LRTIs) are often clinically indistinguishable, leading to antibiotic overuse. We compared the diagnostic accuracy of a new assay that combines 3 host-biomarkers (TRAIL, IP-10, CRP) with parameters in routine use to distinguish bacterial from viral LRTIs. Study cohort included 184 potentially eligible pediatric and adult patients. Reference standard diagnosis was based on adjudication by an expert panel following comprehensive clinical and laboratory investigation (including respiratory PCRs). Experts were blinded to assay results and assay performers were blinded to reference standard outcomes. Evaluated cohort included 88 bacterial and 36 viral patients (23 did not fulfill inclusion criteria; 37 had indeterminate reference standard outcome). Assay distinguished bacterial from viral LRTI patients with sensitivity of 0.93±0.06 and specificity of 0.91±0.09, outperforming routine parameters, including WBC, CRP and chest x-ray signs. These findings support the assay's potential to help clinicians avoid missing bacterial LRTIs or overusing antibiotics.

Drivers of antibiotic prescribing in children and adolescents with febrile lower respiratory tract infections

BACKGROUND

Knowledge of key drivers for antibiotic prescribing in pediatric lower respiratory tract infection (LRTI) could support rational antibiotic use. Thus, we aimed to determine the impact of clinical and laboratory factors on antibiotic prescribing in children and adolescents with febrile LRTI.

METHODS

Pediatric patients from the standard care control group of a randomized controlled trial (ProPAED) investigating procalcitonin guided antibiotic treatment in febrile LRTI were included in a multivariate logistic regression analysis to evaluate the impact of laboratory and clinical factors on antibiotic prescribing.

RESULTS

The standard care control group of the ProPAED study comprised 165 LRTI patients (median age: 2.7 years, range: 0.1-16), out of which 88 (55%) received antibiotic treatment. Factors significantly associated with antibiotic prescribing in patients with complete clinical and laboratory documentation (n = 158) were C-reactive protein (OR 5.8 for a 10-fold increase, 95%CI 2.2-14.9), white blood count beyond age-dependent reference range (OR 3.9, 95%CI 1.4-11.4), body temperature (OR 1.7 for an increase by 1°C, 95%CI 1.02-2.68), and pleuritic pain (OR 2.8, 95%CI 1.1-7.6). Dyspnea (OR 0.3, 95%CI 0.1-0.7) and wheezing (OR 0.3, 95%CI 0.13-0.95) were inversely associated with antibiotic prescribing.

CONCLUSION

Laboratory markers were strong drivers of antibiotic prescribing in children with febrile lower respiratory tract infections, in spite of their known poor prediction of antibiotic need. Building on current guidelines for antibiotic treatment in children with febrile LRTI, a reliable decision algorithm for safe antibiotic withholding considering the laboratory and clinical factors evaluated in this study has the potential to further reduce antibiotic prescribing.

Clinical features and inflammatory markers in pediatric pneumonia: a prospective study

In this prospective, observational study on previously healthy children <18 years, we aimed to study the diagnostic ability of clinical features and inflammatory markers to (i) predict pathologic chest radiography in suspected pneumonia and (ii) differentiate etiology in radiological proven pneumonia. In 394 cases of suspected pneumonia, 265 (67%) had radiographs consistent with pneumonia; 34/265 had proof of bacterial etiology. Of the cases, 86.5% had received pneumococcal conjugate vaccine. In suspected pneumonia, positive chest radiography was significantly associated with increasing C-reactive protein (CRP) values, higher age, and SpO₂ ≤92% in multivariate logistic regression, OR 1.06 (95% CI 1.03 to 1.09), OR 1.09 (95% CI 1.00 to1.18), and OR 2.71 (95% CI 1.42 to 5.18), respectively. In proven pneumonia, bacterial pneumonia was significantly differentiated from viral/atypical pneumonia by increasing CRP values and SpO₂ >92% in multivariate logistic regression, OR 1.09 (95% CI 1.05 to 1.14) and OR 0.23 (95% CI 0.06 to 0.82), respectively. Combining high CRP values (>80 mg/L) and elevated white blood cell (WBC) count provided specificity >85%, positive likelihood ratios >3, but sensitivity <46% for both radiographic proven and bacterial pneumonia.

CONCLUSION

With relatively high specificity and likelihood ratio CRP, WBC count and hypoxemia may be beneficial in ruling in a positive chest radiograph in suspected pneumonia and bacterial etiology in proven pneumonia, but with low sensitivity, the clinical utility is limited. What is Known: • Pneumonia is recommended to be a clinical diagnosis, and neither clinical features nor inflammatory markers can reliably distinguish etiology. • The etiology of pneumonia has changed after routine pneumococcal conjugate vaccine. What is New: • High CRP and WBC counts were associated with infiltrates in children with suspected pneumonia and with bacterial infection in proven pneumonia. • In the post-pneumococcal vaccination era, viral etiology is expected, and in cases of pneumonia with low CRP and WBC counts, a watch-and-wait strategy for antibiotic treatment may be applied.

C-reactive protein and radiographic findings of lower respiratory tract infection in infants

AIM

To evaluate the association between C-reactive protein (CRP) and radiological evidence of lower respiratory tract infection (LRTI) in infants.

METHODS

All patients aged less than 4 years who presented with suspected lower respiratory tract infection, who received a peri-presentation chest radiograph and CRP blood measurement over an 18-mo period were included in the study. Age, gender, source of referral, CRP, white cell count, neutrophil count along with the patients’ symptoms and radiologist’s report were recorded.

RESULTS

Three hundred and eleven patients met the inclusion criteria. Abnormal chest radiographs were more common in patients with elevated CRP levels (P < 0.01). Radiologic signs of LRTI were identified in 73.7% of chest radiographs when a patient had a CRP level between 50-99 mg/L. CRP levels were a better predictor of positive chest radiograph findings for those aged greater than I year compared to those 1 year or less.

CONCLUSION

CRP may be used in patients with suspected LRTI diagnosis to select those who are likely to have positive findings on chest radiograph, thus reducing unnecessary chest radiographs.

Serum Procalcitonin Level Reflects the Severity of Cellulitis

Background

Cellulitis is a common bacterial infection of the superficial skin. Procalcitonin is one of the precursor proteins of calcitonin, its levels are elevated in bacterial infection, and it has been established as a diagnostic marker for severe bacterial infections.

Objective

This study evaluated the clinical usefulness of procalcitonin for predicting disease severity and prognosis of cellulitis.

Methods

We reviewed the medical records of 160 patients diagnosed with cellulitis in the past 3 years. Body temperature, procalcitonin, white blood cell (WBC), erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) levels were measured on their first day of admission. The associations of procalcitonin, WBC, ESR, and CRP with the body temperature and the number of hospitalized days were assessed.

Results

Procalcitonin, WBC, and CRP showed a positive correlation with body temperature. In addition, procalcitonin, WBC, ESR, and CRP showed a positive correlation with number of hospitalized days (p<0.05).

Conclusion

In patients diagnosed with cellulitis, proclacitonin was a helpful parameter to indicate the severity of disease and also a useful predictor of prognosis.

Diagnostic Testing and Hospital Outcomes of Children with Neurologic Impairment and Bacterial Pneumonia

OBJECTIVE

To assess hospital-level variability in diagnostic testing and outcomes for children with neurologic impairment hospitalized with pneumonia.

STUDY DESIGN

A retrospective cohort study of 27 455 children ages 1-18 years with neurologic impairment hospitalized with pneumonia at 39 children's hospitals. K-means clustering was used to assign each hospital to 1 of 3 groups (termed A, B, and C) based on similar diagnostic testing patterns. Outcomes of hospital-level median length of stay (LOS), 30-day readmissions, and pneumonia-associated complications were compared while controlling for patient differences.

RESULTS

Overall, 48.5% had comorbid complex chronic conditions, and 25.4% were assisted with medical technology. Outcomes and diagnostic testing varied across hospitals: median hospital-level LOS, 3.2 days (IQR 2.8-3.8); median readmission, 8.4% (IQR 6.8,-10.0); and median pneumonia-associated complication rate, 23.1% (IQR 18.7-26.8). Despite similar populations, hospitals in group A tended to perform fewer tests than those in groups B and C. Across hospital groups, there was a significant difference in adjusted readmission rates (group A 7.2%, group B 9.0%, group C 7.7%, P = .003). There was no significant difference in adjusted median LOS (group A 3.4 days, group B 3.2 days, group C 3.3 days, P = .3) or adjusted pneumonia-associated complication rates (group A 22.5%, group B 22.5%, group C 25.0%, P = .6).

CONCLUSIONS

For children with neurologic impairment hospitalized with pneumonia, across hospital differences in diagnostic testing were not associated with clinically meaningful differences in outcomes. High-utilizing hospitals may be able to decrease diagnostic testing for children with neurologic impairment hospitalized with pneumonia without adversely impacting outcomes.

Finnish guidelines for the treatment of community-acquired pneumonia and pertussis in children

Evidence-based guidelines are needed to harmonise and improve the diagnostics and treatment of children's lower respiratory tract infections. Following a professional literature search, an interdisciplinary working group evaluated and graded the available evidence and constructed guidelines for the treatment of community-acquired pneumonia and pertussis.

CONCLUSION

The clinical guidelines state that chest radiography is not needed if the child is diagnosed with pneumonia and treated at home. Complications should be considered if there is no improvement after antimicrobial therapy and a paroxysmal cough can indicate pertussis, which is life-threatening in unvaccinated infants and can lead to respiratory failure.

Evaluation of a combined MxA and CRP point-of-care immunoassay to identify viral and/or bacterial immune response in patients with acute febrile respiratory infection

Background

Challenges in the clinical differentiation of viral and/or bacterial respiratory infection lead to the misappropriation of antibiotics and increased healthcare costs. A tool to facilitate rapid and accurate point-of-care (POC) differentiation is needed.

Methods and findings

A prospective, single center, blinded, observational clinical trial was conducted at Beth Israel Deaconess Medical Center from December 2012 to August 2013 to determine the accuracy of a POC immunoassay to identify a clinically significant immune response to viral and/or bacterial infection. Sixty patients with acute febrile respiratory infection (19 pharyngitis and 41 lower respiratory tract infection [LRTI]) were enrolled. Participants provided fingerstick blood for immunoassay testing (myxovirus A [MxA] and c-reactive protein [CRP]) and four oropharyngeal samples for viral PCR and routine bacterial cell culture. A venous blood sample was collected. An ELISA was used to measure CRP and MxA. Paired serological testing was used to confirm atypical bacteria. A urine sample was provided for Streptococcus and Legionella antigen testing. Patients with suspected LRTI had sputum and blood cultures, chest X-ray, and WBC count measured. Viral infection was confirmed if oropharyngeal PCR was positive for viral pathogens. Bacterial infection was confirmed in positive throat or sputum cultures. Elevated immunoglobulin M antibodies or twofold increase in IgG antibodies between acute and convalescent phase indicated atypical bacteria. Positive Streptococcus or Legionella urine antigen assays also confirmed bacterial infection. The immunoassay correctly categorized subjects as 92% (22/24) negative, 80% (16/20) with bacterial infection, and 70% (7/10) with viral infection.

Conclusions

The interplay between an MxA value and a semi-quantitative CRP value can aid in the differentiation of infectious etiology. In isolation, neither MxA nor CRP alone is sensitive or specific. However, the pattern of results in a rapid immunoassay provides a sensitive and specific method to differentiate acute febrile respiratory infections. This diagnostic information may help reduce antibiotic misuse and resistance and lower healthcare costs.

Accuracy and feasibility of point-of-care white blood cell count and C-reactive protein measurements at the pediatric emergency department

Background

Several point-of-care (POC) tests are available for evaluation of febrile patients, but the data about their performance in acute care setting is sparse. We investigated the analytical accuracy and feasibility of POC tests for white blood cell (WBC) count and C-reactive protein (CRP) at the pediatric emergency department (ED).

Methods

In the first part of the study, HemoCue WBC and Afinion AS100 CRP POC analyzers were compared with laboratory’s routine WBC (Sysmex XE-2100) and CRP (Modular P) analyzers in the hospital central laboratory in 77 and 48 clinical blood samples, respectively. The POC tests were then adopted in use at the pediatric ED. In the second part of the study, we compared WBC and CRP levels measured by POC and routine methods during 171 ED patient visits by 168 febrile children and adolescents. Attending physicians performed POC tests in capillary fingerprick samples.

Results

In parallel measurements in the laboratory both WBC and CRP POC analyzers showed good agreement with the reference methods. In febrile children at the emergency department (median age 2.4 years), physician performed POC determinations in capillary blood gave comparable results with those in venous blood analyzed in the laboratory. The mean difference between POC and reference test result was 1.1 E9/L (95% limits of agreement from -6.5 to 8.8 E9/L) for WBC and -1.2 mg/L (95% limits of agreement from -29.6 to 27.2 mg/L) for CRP.

Conclusions

POC tests are feasible and relatively accurate methods to assess CRP level and WBC count among febrile children at the ED.

RNA transcriptional biosignature analysis for identifying febrile infants with serious bacterial infections in the emergency department: a feasibility study

OBJECTIVES

To develop the infrastructure and demonstrate the feasibility of conducting microarray-based RNA transcriptional profile analyses for the diagnosis of serious bacterial infections in febrile infants 60 days and younger in a multicenter pediatric emergency research network.

METHODS

We designed a prospective multicenter cohort study with the aim of enrolling more than 4000 febrile infants 60 days and younger. To ensure success of conducting complex genomic studies in emergency department (ED) settings, we established an infrastructure within the Pediatric Emergency Care Applied Research Network, including 21 sites, to evaluate RNA transcriptional profiles in young febrile infants. We developed a comprehensive manual of operations and trained site investigators to obtain and process blood samples for RNA extraction and genomic analyses. We created standard operating procedures for blood sample collection, processing, storage, shipping, and analyses. We planned to prospectively identify, enroll, and collect 1 mL blood samples for genomic analyses from eligible patients to identify logistical issues with study procedures. Finally, we planned to batch blood samples and determined RNA quantity and quality at the central microarray laboratory and organized data analysis with the Pediatric Emergency Care Applied Research Network data coordinating center. Below we report on establishment of the infrastructure and the feasibility success in the first year based on the enrollment of a limited number of patients.

RESULTS

We successfully established the infrastructure at 21 EDs. Over the first 5 months we enrolled 79% (74 of 94) of eligible febrile infants. We were able to obtain and ship 1 mL of blood from 74% (55 of 74) of enrolled participants, with at least 1 sample per participating ED. The 55 samples were shipped and evaluated at the microarray laboratory, and 95% (52 of 55) of blood samples were of adequate quality and contained sufficient RNA for expression analysis.

CONCLUSIONS

It is possible to create a robust infrastructure to conduct genomic studies in young febrile infants in the context of a multicenter pediatric ED research setting. The sufficient quantity and high quality of RNA obtained suggests that whole blood transcriptional profile analysis for the diagnostic evaluation of young febrile infants can be successfully performed in this setting.

Biomarkers for community-acquired pneumonia in the emergency department

Community-acquired pneumonia is one of the most common reasons for emergency department (ED) visits in children and adults. Despite its prevalence, there are many challenges to proper diagnosis and management of pneumonia. There is no accurate and timely etiologic gold standard to differentiate bacterial from viral disease, and there are limitations with precise risk stratification of patients to ensure appropriate site-of-care decisions. Clinical factors obtained by history and physical examination have limited the ability to diagnose pneumonia etiology and severity. Biomarkers offer information about the host response to infection and pathogen activity within the host that can serve to augment clinical features in decision-making. As science and technology progress, novel biomarkers offer great potential in aiding critical decisions for patients with pneumonia. This review summarizes existing knowledge about biomarkers of host response and pathogen activity, in addition to briefly reviewing emerging biomarkers using novel technologies.

Rapid C-reactive protein and white cell tests decrease cost and shorten emergency visits

BACKGROUND

Elevated white blood cells (WBC) in blood and C-reactive protein (CRP) in serum are often used as non-specific markers for bacterial etiology of infection in children. The aim of the present study was to evaluate how rapid WBC and CRP testing influences patient flow and cost in the pediatric emergency room (ER).

METHODS

This study was a retrospective chart review. In all, 166 children who were treated during 3 months in the ER of a children's hospital, and in whom rapid tests for WBC and CRP were done, were included. The association between rapid testing and length of ER stay was evaluated, and the cost of rapid tests was compared with the corresponding cost if done in the hospital laboratory.

RESULTS

Median ER stay was 147.5 min, if no examinations other than rapid CRP and WBC tests were done and if no emergency treatment was given, compared with 201.5 min for laboratory tests or emergency treatment given (P < 0.001). The respective figures were 142.5 min and 179.5 min in those 96 children discharged home (P = 0.003). The cost of rapid testing was only 41.5% of the corresponding laboratory cost.

CONCLUSION

The simultaneous rapid testing of CRP and WBC in children with presumable infection decreased cost and shortened the length of ER stay, if no other examinations or emergency treatment were needed. The cost of rapid testing was less than half of the corresponding cost in laboratory.

The effect of experimental streptococcus infection in myocarditis on some biochemical and inflammatory markers in albino rats

BACKGROUND

Myocarditis is an uncommon disease that presents with a wide range of symptoms in children and adults. It is histologically characterized by varying degrees of myocardialnecrosis, edema and cellular infiltration myocardial inflammation is a nonspecificresponse to many triggers such as bacterial infection, cardio toxic agents, ormechanical injury.

OBJECTIVE

This study was carried out to investigate the experimental Streptococcus faecalis induction of myocarditis and its effect on some blood parameters, inflammatory markers and histopathological changes in male albino rats.

METHODS

Rats were infected by intraperitoneal injection of 10 8 CFU/ml of Streptococcus faecalis and sacrificed after one, two and seven days post infection. Biochemical analyses of blood were carried out to investigate the serum biomarkers of inflammation, liver function tests, cardiac enzymes & kidney function tests.

RESULTS

All biochemical analyses showed statistically significant increase in the measured parameters due to bacterial infections except for blood urea which appear to be normal. A significant positive correlation was observed between lactate dehydrogenase enzyme (LDH) with creatinine (r =0.778, P<0.01). In the 7 days group, there were significant positive correlations between aspartate aminotransferase (AST) and alanine aminotransferase (ALT) (r=0.675, P<0.05), erythrocyte sedimentation rate (ESR) with Urea (r=0.659, P<0.05) and alkaline phosphatase (ALP) with C-reactive protein (CRP) (r=0.765, p<0.01).

CONCLUSION

Many of these biomarkers will provide important new insights into pathophysiology and aid in the diagnosis and management of cardiovascular patients.

Bacterial infection (BI)-INDEX: an improved and simplified rapid flow cytometric bacterial infection marker

The aim of this study was to develop a rapid and simple flow cytometric bacterial infection marker. In this prospective comparative study, quantitative flow cytometric analysis of CD10, CD35, CD66b, CD282, and MHC Class I molecules on human neutrophils, monocytes, and B-lymphocytes from 141 hospitalized febrile patients with suspected infection and from 50 healthy controls was performed. We developed a flow cytometric marker of local and systemic bacterial infections, designated "bacterial infection (BI)-INDEX", incorporating the quantitative analysis of CD10, CD35, MHCI, CD66b, and CD282 on neutrophils, monocytes, and B-lymphocytes, which displayed 90% sensitivity and 96% specificity in distinguishing between microbiologically confirmed bacterial (n = 31) and viral infections (n = 27) within a 1-h time-frame. We propose that our novel rapid BI-INDEX test will be useful in assisting physicians to ascertain whether antibiotic treatment is required, thus limiting unnecessary antimicrobial usage.

Variation in emergency department diagnostic testing and disposition outcomes in pneumonia

OBJECTIVE

To describe the variability across hospitals in diagnostic test utilization for children diagnosed with community-acquired pneumonia (CAP) during emergency department (ED) evaluation and to determine if test utilization is associated with hospitalization and ED revisits.

METHODS

We conducted a retrospective cohort study of children aged 2 months to 18 years with ED visits resulting in CAP diagnoses from 2007 to 2010 who were seen at 36 hospitals contributing data to the Pediatric Health Information System. Children with complex chronic conditions, recent hospitalization, trauma, aspiration, or perinatal infection were excluded. Primary outcomes included diagnostic testing, hospitalization, and 3-day ED revisit rates across hospitals. We examined variation in diagnostic testing among hospitals by using multivariable mixed-effects logistic regression.

RESULTS

A total of 100,615 ED visits were analyzed. Complete blood count (median: 28.7%), blood culture (27.9%), and chest radiograph (75.7%) were the most commonly ordered ED diagnostic tests. After adjustment for patient characteristics, significant variation (P < .001) was found for each test examined across hospitals. High test-utilizing hospitals had increased odds of hospitalization compared with low-utilizing hospitals (odds ratio: 1.86 [95% confidence interval: 1.17-2.94]; P = .008). However, differences in the odds of ED revisit between the low- and high-utilizing hospitals were not significant (odds ratio: 1.21 [95% confidence interval: 0.97-1.51]; P = .09).

CONCLUSIONS

Emergency departments that use more testing in diagnosing CAP have higher hospitalization rates than lower-utilizing EDs. However, ED revisit rates were not significantly different between high- and low-utilizing EDs. These results suggest an opportunity to reduce diagnostic testing for CAP without negatively affecting outcomes.

The association of positive chest radiograph and laboratory parameters with community acquired pneumonia in children

CONTEXT

This study was designed to compare the sensitivities of different investigations for the diagnosis of Community Acquired Pneumonia (CAP). A prospective study was carried out which compared the sensitivities of the chest radiographs, CRP, TLC, ESR and the blood cultures in sixty-six patients who were diagnosed with WHO defined CAP.

METHOD AND MATERIAL

The chest radiographs, serum C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), total leucocyte count (TLC) and blood cultures were determined in sixty-six patients who were amongst the age group of one month to five years of age, who were diagnosed with WHO defined CAP.

STATISTICAL ANALYSIS

It was carried out by calculating the proportion, mean, standard deviation (SD) and the sensitivity of the test/.able

RESULTS

The chest radiographs were found to be positive in 93.9% (n=62) patients, CRP was positive in 90.9% (n=60) patients, ESR was positive in 72.7% (n=42) patients, TLC was positive in 48.5% (n=38) patients and the blood cultures were positive in 6.1% (n=4) patients. Hence, the sensitivity of the chest radiograph, CRP, ESR, TLC and the blood culture in the diagnosis of CAP were 93.9%, 90.9%, 72.7%, 48.5% and 6.1%.

CONCLUSION

In view of the high sensitivity of CRP, which is almost similar to that of chest X-Ray in detecting CAP, CRP can be used as an alternative test to the chest radiographs at peripheral centres, where X-ray machines are not available.

Diagnostic value and prognostic significance of pleural C-reactive protein in lung cancer patients with malignant pleural effusions

PURPOSE

C-reactive protein (CRP) has been implicated in various inflammatory and advanced malignant states. Increased serum CRP (s-CRP) levels have been shown to be associated with independent prognostic factors for survival in patients with advanced lung cancer. However, only few studies have focused on the role of CRP in pleural effusions. This study aimed to evaluate the diagnostic and prognostic value of pleural CRP (p-CRP) in lung cancer patients with malignant pleural effusion (MPE).

MATERIALS AND METHODS

Pleural effusion (PE) samples were collected from patients with MPE (68 lung cancers; 12 extrathoracic tumors), and from 68 patients with various benign conditions (31 with pneumonia; 37 with tuberculosis). Concentrations of p- and s-CRP were measured by enzyme-linked immunosorbent assay. CRP level in pleural fluid and its association with survival were examined.

RESULTS

p-CRP levels correlated with s-CRP levels (r=0.82, p<0.0001). For the differential diagnosis of MPE and benign PE, the area under the receiver operating characteristic curve was greater for p-CRP (0.86) than for s-CRP (0.77). High p-CRP expression significantly correlated with shorter overall survival (p=0.006). P-CRP was independent prognostic factor significantly associated with overall survival on multivariated analysis (p=0.0001). The relative risk of death for lung cancer patients with high p-CRP levels was 3.909 (95% confidence interval, 2.000-7.639).

CONCLUSION

P-CRP is superior to s-CRP in determining pleural fluid etiology. Quantitative measurement of p-CRP might be a useful complementary diagnostic and prognostic test for lung cancer patients with MPE.

Procalcitonin in pediatrics

Over the past two decades, the body of literature on the clinical usefulness of procalcitonin (PCT) in adults has grown rapidly. Although this approach has led to increased insight, it has also prompted debate regarding its potential use in diagnosis and management of severe infection. Clinicians, however, are less familiar with the use of PCT in pediatric populations. In this review, we examine PCT as a marker of severe clinical pediatric conditions including its role in systemic inflammation, infection, and sepsis.

A rapid flow cytometric method for distinguishing between febrile bacterial and viral infections

Antibiotic resistance due to the inappropriate use of antimicrobials is one of the most critical public health problems worldwide. A major factor underlying the unnecessary use of antibiotics is the lack of rapid and accurate diagnostic tests. Therefore, we aimed to develop a novel rapid flow cytometric method for distinguishing between febrile bacterial and viral infections. In this prospective comparative study, quantitative flow cytometric analysis of FcγRII/CD32, CR1/CD35, MHC Class I receptor (MHCI), and C5aR/CD88 on human phagocytes was performed in 286 hospitalized febrile patients with suspected infection. After using microbiological and serological detection methods, or clinical diagnosis, 205 patients were identified with either bacterial (n=136) or viral (n=69) infection. Receptor data from patients were compared to those of 50 healthy controls. We developed a flow cytometric marker of local and systemic bacterial infections designated "bacterial infection score (BIS)" incorporating the quantitative analysis of FcγRII/CD32, CR1/CD35, C5aR/CD88 and MHCI on neutrophils and/or monocytes, which displays 91% sensitivity and 92% specificity in distinguishing between microbiologically confirmed bacterial (n=77) and serologically confirmed viral infections (n=61) within 1h. The BIS method was effectively applied to distinguish between bacterial and viral (pandemic H1N1 influenza) pneumonia cases with 96% sensitivity and 92% specificity. We propose that the rapid BIS test can assist physicians in deciding whether antibiotic treatment is necessary, thus reducing unnecessary antimicrobial use.

Antibiotic therapy for pediatric community-acquired pneumonia: do we know when, what and for how long to treat?

Community-acquired pneumonia (CAP) is a common cause of morbidity among children in developed countries and accounts for an incidence of 10-40 cases per 1000 children in the first 5 years of life. Given the clinical, social and economic importance of CAP, there is general agreement that prompt and adequate therapy is essential to reduce the impact of the disease. The aim of this discussion paper is to consider critically the available data concerning the treatment of uncomplicated pediatric CAP and to consider when, how and for how long it should be treated. This review has identified the various reasons that make it difficult to establish a rational approach to the treatment of pediatric CAP, including the definition of CAP, the absence of a pediatric CAP severity score, the difficulty of identifying the etiology, limited pharmacokinetic (PK)/pharmacodynamic (PD) studies, the high resistance of the most frequent respiratory pathogens to the most widely used anti-infectious agents and the lack of information concerning the changes in CAP epidemiology following the introduction of new vaccines against respiratory pathogens. More research is clearly required in various areas, such as the etiology of CAP and the reasons for its complications, the better definition of first- and second-line antibiotic therapies (including the doses and duration of parenteral and oral antibiotic treatment), the role of antiviral treatment and on how to follow-up patients with CAP. Finally, further efforts are needed to increase vaccination coverage against respiratory pathogens and to conduct prospective studies of their impact.

Evaluation of the World Health Organization criteria for chest radiographs for pneumonia diagnosis in children

Our objective was to compare the inter-observer level of agreement in diagnosing pneumonia using the World Health Organization (WHO) guidelines for the interpretation of radiographs. We conducted a prospective study in a pediatric emergency room. Fifteen observers (13 pediatricians, 2 radiologists) interpreted 200 pediatric (<5 years old) chest radiographs using the WHO guidelines. Observers were blinded to the clinical presentation. RESULTS were analyzed for kappa values. Individual readings were compared to two "gold standard" teams: (1) radiologist and pediatrician and (2) two radiologists.

RESULTS

Alveolar pneumonia, non-alveolar pneumonia, and no pneumonia were found (by radiologists) in 12.8%, 2.7%, and 78.6% of readings, respectively. The mean kappa values for alveolar pneumonia, non-alveolar pneumonia, and no pneumonia of observers versus the team consisting of a radiologist and a pediatrician were 0.73, 0.23, and 0.61, respectively. For non-alveolar pneumonia, the mean kappa value was higher for the gold standard consisting of a radiologist and a pediatrician when compared to the two-radiologist team. Pediatricians overdiagnosed "non-alveolar pneumonia" compared with radiologists. In contrast, for the alveolar pneumonia and no-pneumonia diagnoses, no significant differences were found.

CONCLUSIONS

The WHO guidelines for interpretation of chest radiographs result in high level of agreement between readers for the definition of "alveolar pneumonia" and "no pneumonia" but poor agreement for non-alveolar pneumonia. The disagreement with regard to the latter was associated with overdiagnosis by pediatricians, which may lead to overtreatment. We believe that radiographic non-alveolar pneumonia should not be an endpoint for clinical trials and research, nor should it be implemented in clinical setting.

The management of community-acquired pneumonia in infants and children older than 3 months of age: clinical practice guidelines by the Pediatric Infectious Diseases Society and the Infectious Diseases Society of America

Evidenced-based guidelines for management of infants and children with community-acquired pneumonia (CAP) were prepared by an expert panel comprising clinicians and investigators representing community pediatrics, public health, and the pediatric specialties of critical care, emergency medicine, hospital medicine, infectious diseases, pulmonology, and surgery. These guidelines are intended for use by primary care and subspecialty providers responsible for the management of otherwise healthy infants and children with CAP in both outpatient and inpatient settings. Site-of-care management, diagnosis, antimicrobial and adjunctive surgical therapy, and prevention are discussed. Areas that warrant future investigations are also highlighted.

Procalcitonin measurements for guiding antibiotic treatment in pediatric pneumonia

In order to evaluate the use of an algorithm based on a procalcitonin (PCT) cut-off value as a means of guiding antibiotic therapy, 319 hospitalised children with uncomplicated community-acquired pneumonia (CAP) were randomised 1:1 to be treated on the basis of the algorithm or in accordance with standard guidelines. The children in the PCT group did not receive antibiotics if their PCT level upon admission was <0.25 ng/mL, and those receiving antibiotics from the time of admission were treated until their PCT level was ≥ 0.25 ng/mL. The final analysis was based on 155 patients in the PCT group and 155 in the control group. In comparison with the controls, the PCT group received significantly fewer antibiotic prescriptions (85.8% vs 100%; p < 0.05), were exposed to antibiotics for a shorter time (5.37 vs 10.96 days; p < 0.05), and experienced fewer antibiotic-related adverse events (3.9% vs 25.2%; p < 0.05), regardless of CAP severity. There was no significant between-group difference in recurrence of respiratory symptoms and new antibiotic prescription in the month following enrollment. The results of this first prospective study using a PCT cut-off value to guide antibiotic therapy for pediatric CAP showed that this approach can significantly reduce antibiotic use and antibiotic-related adverse events in children with uncomplicated disease. However, because the study included mainly children with mild to moderate CAP and the risk of the use of the algorithm-based approach was not validated in a relevant number of severe cases, further studies are needed before it can be used in routine clinical practice.

Expression, regulation and clinical significance of soluble and membrane CD14 receptors in pediatric inflammatory lung diseases

Background

Inflammatory lung diseases are a major morbidity factor in children. Therefore, novel strategies for early detection of inflammatory lung diseases are of high interest. Bacterial lipopolysaccharide (LPS) is recognized via Toll-like receptors and CD14. CD14 exists as a soluble (sCD14) and membrane-associated (mCD14) protein, present on the surface of leukocytes. Previous studies suggest sCD14 as potential marker for inflammatory diseases, but their potential role in pediatric lung diseases remained elusive. Therefore, we examined the expression, regulation and significance of sCD14 and mCD14 in pediatric lung diseases.

Methods

sCD14 levels were quantified in serum and bronchoalveolar lavage fluid (BALF) of children with infective (pneumonia, cystic fibrosis, CF) and non-infective (asthma) inflammatory lung diseases and healthy control subjects by ELISA. Membrane CD14 expression levels on monocytes in peripheral blood and on alveolar macrophages in BALF were quantified by flow cytometry. In vitro studies were performed to investigate which factors regulate sCD14 release and mCD14 expression.

Results

sCD14 serum levels were specifically increased in serum of children with pneumonia compared to CF, asthma and control subjects. In vitro, CpG induced the release of sCD14 levels in a protease-independent manner, whereas LPS-mediated mCD14 shedding was prevented by serine protease inhibition.

Conclusions

This study demonstrates for the first time the expression, regulation and clinical significance of soluble and membrane CD14 receptors in pediatric inflammatory lung diseases and suggests sCD14 as potential marker for pneumonia in children.