Prognostic scores and biomarkers for pediatric community-acquired pneumonia: how far have we come?

Prevalence and factors associated with admission to the intensive care unit in children hospitalized for community-acquired pneumonia

OBJECTIVE.

To determine the prevalence and factors associated with intensive care unit admission in children and adolescents with community-acquired pneumonia.

MATERIALS AND METHODS.

Analytical cross-sectional observational study at the Instituto Nacional de Salud del Niño San Borja in 2019. The sample consisted of children older than one month and younger than 18 years who were admitted to emergency diagnosed with community-acquired pneumonia. We used Poisson regression to assess association.

RESULTS.

We evaluated 166 patients diagnosed with pneumonia, 94 (56.6%) were male and the median age was 24 months (IQR: 11 - 48). Most patients had a mild modified PIRO score of 136 (81.9%); 31 (18.7%) patients had complicated pneumonia and 24 (14.5%) were admitted to intensive care. The higher the age, the lower the prevalence of admission to ICU (PR=0.99, 95%CI: 0.98-0.99). The severity assessed with the modified PIRO score (PR=3.40, 95%CI: 1.46-7.93) and the presence of complicated pneumonia (PR: 5.88, 95%CI: 2.46-14.06) were associated with admission to intensive care.

CONCLUSIONS.

The prevalence of admission to intensive care in children with community-acquired pneumonia was 14.5%. Younger patients with pneumonia, with greater severity assessed with the modified PIRO score and with complicated pneumonia have a higher prevalence of admission to intensive care.

The Role of Mannose-Binding Lectin and Inflammatory Markers in Establishing the Course and Prognosis of Community-Acquired Pneumonia in Children

BACKGROUND

Community-acquired pneumonia (CAP) is one of the most significant childhood diseases worldwide and a leading infectious cause of death in children. This study aimed to evaluate the prognostic value of the inflammatory markers-C-reactive protein (CRP) and procalcitonin (PCT)-and the polymorphic glycoprotein mannose-binding lectin (MBL), deficiency of which is associated with severe infections, in the determination of the optimal type and timing of therapeutic intervention for CAP in childhood.

METHODS

Retrospective evaluation was conducted on a cohort of 204 children aged 4 months-17 years hospitalized with CAP. Their levels of CRP, PCT, and MBL were assessed for their association with a variety of outcomes, including the incidence of local and systemic complications, admission to the ICU, duration of antibiotic treatment and hospital stay, and death.

RESULTS

CRP and PCT proved to be better predictors of complications of CAP than MBL. The area under the curve (AUC) value was highest for PCT as a predictor of systemic complications (AUC = 0.931, 95%CI 0.895-0.967), while CRP (AUC = 0.674, 95%CI 0.586-0.761) performed best as a predictor of local complications (AUC = 0.674, 95%CI 0.586-0.761). Regarding admission to the ICU, CRP was the weakest predictor (AUC = 0.741), while PCT performed the best (AUC = 0.833), followed by MBL (AUC = 0.797). Sensitivity and specificity were calculated for the optimal threshold generated by receiver operating characteristic (ROC) curves, rendering sensitivity of 90% and specificity of 87% for PCT in assessing the risk of systemic complications, compared to sensitivity of 83% and specificity of 90% for CRP. MBL showed relatively high sensitivity (96%) but low specificity (25%) for predicting the need for ICU admission.

CONCLUSIONS

Early measurement of CRP, PCT, and MBL provides clinicians with important information regarding the course and prognosis of children diagnosed with CAP, thus ensuring prompt, optimal therapeutic management.

Interpretations of the Role of Plasma Albumin in Prognostic Indices: A Literature Review

This review assesses how publications interpret factors that influence the serum or plasma albumin (PA) level in prognostic indices, focusing on inflammation and nutrition. On PubMed, a search for "albumin AND prognosis" yielded 23,919 results. From these records, prognostic indices were retrieved, and their names were used as search strings on PubMed. Indices found in 10 or more original research articles were included. The same search strings, restricted to "Review" or "Systematic review", retrieved yielded on the indices. The data comprised the 10 latest original research articles and up to 10 of the latest reviews. Thirty indices had 294 original research articles (6 covering two indices) and 131 reviews, most of which were from recent years. A total of 106 articles related the PA level to inflammation, and 136 related the PA level to nutrition. For the reviews, the equivalent numbers were 54 and 65. In conclusion, more publications mention the PA level as a marker of nutrition rather than inflammation. This is in contrast to several general reviews on albumin and nutritional guidelines, which state that the PA level is a marker of inflammation but not nutrition. Hypoalbuminemia should prompt clinicians to focus on the inflammatory aspects in their patients.

Red Blood Cell Distribution Width and Pediatric Community-Acquired Pneumonia Disease Severity

BACKGROUND AND OBJECTIVES

No standardized risk assessment tool exists for community-acquired pneumonia (CAP) in children. This study aims to investigate the association between red blood cell distribution width (RDW) and pediatric CAP.

METHODS

Data prospectively collected by the Etiology of Pneumonia in the Community study (2010-2012) was used. Study population was pediatric patients admitted to tertiary care hospitals in Nashville and Memphis, Tennessee with clinically and radiographically confirmed CAP. The earliest measured RDW value on admission was used, in quintiles and also as a continuous variable. Outcomes analyzed were: severe CAP (requiring ICU, mechanical ventilation, vasopressor support, or death) or moderate CAP (hospital admission only). Analysis used multivariable logistic regression and restricted cubic splines modeling.

RESULTS

In 1459 eligible children, the median age was 29 months (interquartile range: 12-73), median RDW was 13.3% (interquartile range: 12.5-14.3), and 289 patients (19.8%) developed severe disease. In comparison with the lowest RDW quintile (Q1), the adjusted odds ratio (95% CI) for severe CAP in subsequent quintiles were, Q2: 1.20 (0.72-1.99); Q3: 1.28 (0.76-2.14); Q4: 1.69 (1.01-2.82); Q5: 1.25 (0.73-2.13). Consistently, RDW restricted cubic splines demonstrated an independent, nonlinear, positive association with CAP severity (P = .027), with rapid increases in the risk of severe CAP with RDW values up to 15%.

CONCLUSIONS

Higher presenting RDW was associated with an increased risk of severe CAP in hospitalized children. Widely available and inexpensive, RDW can serve as an objective data point to help with clinical assessments.

Pediatric pneumonia (PedPne) lung ultrasound score and inflammatory markers: A pilot study

INTRODUCTION

Pneumonia is the principal cause of death among children worldwide. Lung ultrasound (LUS) is a reliable tool for the diagnosis and assessment of community-acquired pneumonia in children. Furthermore, objective parameters, including the pneumonia LUS score, might be useful for pneumonia monitoring. Thus, our aim was to present a newly developed LUS score for pediatric pneumonia (PedPne) and evaluate its relationship with commonly assessed inflammatory markers.

METHODS

Children referred to the Pediatric Pneumology Clinic between September 2017 and February 2018 with suspected pneumonia were screened for eligibility for inclusion in the study and informed consent was obtained. In addition to clinical assessment, LUS was performed during consultation, and inflammatory biomarkers, including C-reactive protein level, erythrocyte sedimentation rate (ESR), and leukocyte count, were measured in all inpatients. An LUS score for pneumonia and pleurisy in children (pediatric pneumonia lung ultrasound score [PedPne LUS]) was subsequently developed. Chest radiography (CXR) was also performed according to local guidelines for pneumonia diagnosis. Spearman's correlation test was used to evaluate the correlation between the PedPne score and inflammatory markers.

RESULTS

A total of 217 patients were screened, of which 64 patients diagnosed with consolidated pneumonia were included in this study. The median PedPne LUS score of the included patients was 8.02, which was consistent with the consolidations detected on LUS and confirmed by CXR. A very strong positive correlation was found between the LUS PedPne score and C-reactive protein and ESR, and a good correlation was found with the leukocyte count.

CONCLUSION

The LUS pneumonia score is a reliable parameter for the evaluation of pneumonia, and shows a strong correlation with inflammatory biomarkers. The PedPne LUS score is a potential noninvasive surrogate parameter of inflammation in pediatric pneumonia.

Age-specific risk factors of severe pneumonia among pediatric patients hospitalized with community-acquired pneumonia

BACKGROUND

Risk factors that predispose the development of severe community-acquired pneumonia (CAP) among pediatric CAP patients of different age ranges are yet to be identified.

METHODS

We retrospectively analyzed pediatric in-patients (< 6 years old) diagnosed with CAP in our hospital. We subdivided patients into four age groups (< 6 months, 6 months-1 year, 1-2 years, and 2-6 years). Their medical records, including demographic information, clinical features, laboratory findings, and chest radiographic reports, were reviewed and collected for further analysis. Univariate logistic regression analysis and stepwise regression analysis were applied to identify risk factors associated with severe CAP and ICU admission for overall patients and age-stratified subgroups.

RESULTS

A total of 20,174 cases were initially included. Among them, 3309 (16.40%) cases were identified as severe CAP, and 2824 (14.00%) cases required ICU admission. Potential risk factors for severe CAP and ICU admission identified by univariate analysis included younger age, rural residency, premature birth, low birth weight (LBW), formula feeding, congenital heart disease (CHD), history of pneumonia or neonatal jaundice, patients with other health issues, certain symptoms (manifesting wheezing, dyspnea, cyanosis, but have no cough or fever), abnormal laboratory findings (abnormal levels of white blood cells, albumin, and C-reactive protein and RSV infection), and chest X-ray (odds ratio [OR] > 1 for all). CHD, low albumin, proteinuria, abnormal chest x-ray were independent risks factors across different age groups, whereas birth or feeding history, history of pneumonia, cyanosis or dyspnea on admission, and RSV infection were independent risk factors for only younger kids (< 1 year), and wheezing was an independent risk factor only for older children (2-5 years old).

CONCLUSIONS

Risk factors predicting disease severity among children hospitalized with CAP vary with age. Risk factor stratification of pediatric CAP based on age-specific risk factors can better guide clinical practice.

TRIAL REGISTRATION

This study has been registered in China, with the registration number being ChiCTR2000033019 .

Modified PIRO (predisposition, insult, response, organ dysfunction) severity score as a predictor for mortality of children with pneumonia in Hasan Sadikin Hospital, Bandung, Indonesia

Background

Clinical manifestations for pneumonia vary from mild to severe. The PIRO model (predisposition, insult, response, organ dysfunction) was used as scoring system to determine severity of sepsis and pneumonia in adult patients. The PIRO model was modified for sorting the severity of pneumonia in children and predicting its risk of mortality.

Methods

An ambispective cohort study of pneumonia patients aged 1 month to ≤ 18 years admitted over the period from May to September 2020. Data were collected from history, physical examination, laboratory examination, and chest radiography. Based on bivariate analysis (p<0.05 and relative risk (RR) with 95% confidence interval), variables of each PIRO component that were significant for mortality were assigned a value of 1. The cut-off score for predictor of mortality was calculated using the receiver operating characteristics (ROC) curve and the scores were stratified into three degrees of risk based on interquartile range, score ≤Q1 was categorized as low risk; Q1-Q3 was categorized as moderate risk; and score >Q3 was categorized as high risk.

Results

Out of the 80 subjects enrolled, 6 months-5 years was the largest age group (56.3%). The observed mortality was 15/80 (18.8%). The modified PIRO severity score was compiled from significant variables of predisposition (malnutrition), insult (chest radiograph), response (hypoxemia, hypotension, CRP >0.5 mg/dL, PCT >0.5 ng/dL) and organ dysfunction, with range of score 0-7. Score >3 was categorized as a cut-off point score for predictor of mortality with AUC 0.919 (95% CI 0.836–0.968), sensitivity of 80%, and specificity of 84.62%. Subjects with score >3 have RR of 10.544 compared to those with score ≤3. The stratification of score level was low (≤2), moderate (3-4), and high (5-7). The mortality levels were 0%, 46.7%, and 53.3%, respectively.

Conclusions

Modified PIRO severity score can be used as a sorting tool and predictor of mortality risk in children with pneumonia. This score can also be used to select candidates for intensive care, especially in health facilities with limited intensive care capacity.

Blood biomarkers differentiating viral versus bacterial pneumonia aetiology: a literature review

Background and objectives

The goal of this literature review is to compare current studies regarding the accuracy of different serum markers in differentiating viral from bacterial pneumonia in the pediatric population with what is employed in the medical settings at present. Currently there is still a lack of significant research, that would give us evaluation on biomarkers benefits towards getting a definite diagnosis of pneumonia. Finding out the potential of biomarkers to differentiate between viral and bacterial pneumonia is also important because knowing the exact pathogen would prevent irrational use of antibiotics. At present, irrational, broad-spectrum antibiotic use and increasing antibiotic resistance in microorganisms are still one of the greatest challenges in clinical settings. The use of biomarkers in clinical practice would not only facilitate accurate diagnosis, but would also help to reduce the amount of antibiotics overuse.

Materials and methods

Literature search conducted on Medline and Google Scholar using a combination of terms. Articles that were in English and within ten years of the search date were manually sorted according to inclusion and exclusion criteria. Results: Initial search returned n = 13,408. After activating filters, n = 140 were identified of which n = 12 included for literature review.

Conclusions

Rise or drop in the concentration of a single marker is not accurate enough for predicting viral/bacterial community acquired pneumonia. This is because there is overlapping to a varying extent depending on the marker cut-off values, detection methods, analyses, the desired specificity, and sensitivity. Furthermore, the presence of mixed infection makes almost all markers suboptimal to be used universally. New markers such as MxA1 and HMGB1 gave promising results. However, to replicate a similar testing condition in a clinical environment may not be practical. Another approach is to make use of more than one marker and combine with clinical signs and symptoms. This may not be cost-effective in many clinical settings; nevertheless, in many studies, marker combination greatly improved the predictive power.

Host Inflammatory Biomarkers of Disease Severity in Pediatric Community-Acquired Pneumonia: A Systematic Review and Meta-analysis

Background

Community-acquired pneumonia (CAP) is the leading cause of death in children. Identification of reliable biomarkers offers the potential to develop a severity quantitative score to assist in clinical decision-making and improve outcomes.

Methods

A systematic review and meta-analysis was performed in PubMed and EMBASE on November 13, 2018, to examine the association between host inflammatory biomarkers and CAP severity in children. The inclusion criteria were case–control, cross-sectional, and cohort studies that examined candidate serum biomarkers. We extracted outcomes of interest, means, and standardized mean differences (SMDs) of plasma and serum levels of biomarkers together with information on disease severity. Meta-analysis was performed. This review was registered in the PROSPERO international registry (CRD42019123351).

Results

Two hundred seventy-two abstracts were identified, and 17 studies were included. Among the biomarkers evaluated, levels of C-reactive protein (CRP; SMD, 0.63; 95% confidence interval [CI], 0.35 to 0.91), interleukin (IL)-6 (SMD, 0.46; 95% CI, 0.25 to 0.66), IL-8 (SMD, 0.72; 95% CI, 0.15 to 1.29), neutrophil count (SMD, 0.27; 95% CI, 0.07 to 0.47), and procalcitonin (SMD, 0.68; 95% CI, 0.20 to 1.15) were substantially increased in severe CAP. In contrast, IL-2 concentrations (SMD, –0.24; 95% CI, –0.45 to –0.03) were higher in nonsevere CAP. Study heterogeneity was reported to be high (I² > 75%), except for IL-2, IL-5, IL-6, and IL-12p70, which were classified as moderate (I² = 50%–74%). Only neutrophil and white blood cell counts were described by studies exhibiting a low level of heterogeneity.

Conclusions

Our results suggest that host biomarkers, and especially CRP, IL-6, IL-8, and procalcitonin levels, have the potential to predict severe CAP in pediatric populations.

Plasma procalcitonin concentrations predict organ dysfunction and outcome in dogs with sepsis

Background

Procalcitonin (PCT) is a valuable prognostic biomarker in human sepsis that is predictive of organ dysfunction, septic shock and mortality. Data on PCT in dogs is limited. This study aimed to investigate the prognostic value of baseline and serial PCT measurements in dogs with sepsis and to determine the association between PCT and sepsis severity and the presence of organ dysfunction. PCT concentrations were measured in citrated plasma samples collected from 53 dogs with sepsis at the time of admission (T0, n = 53) and at 24 h (T1, n = 35) and 48 h (T2, n = 30) post-admission using a commercial ELISA. Dogs were classified by sepsis severity (sepsis without organ dysfunction; severe sepsis; septic shock) and outcome (survivors; non-survivors). Organ dysfunctions were recorded at T0 and during hospitalization, and the APPLE_fast score calculated at T0. Healthy dogs (n = 12) were used as controls.

Results

There were 18 septic dogs without organ dysfunction, 24 dogs with severe sepsis and 11 with septic shock. Baseline PCT concentrations were significantly greater in dogs with sepsis compared to healthy controls (P < 0.0001), and in dogs with septic shock compared to dogs without cardiovascular compromise (P = 0.01). Baseline PCT was significantly correlated with organ dysfunction (P = 0.003). Declining PCT concentrations were documented in survivors at T1 and T2 compared to PCT at T0 (P = 0.0006), and PCT clearance at 24 h was significantly higher in survivors (n = 38) compared to non-survivors (n = 15) (P = 0.037). Canine APPLE_fast score was not predictive of sepsis severity, the development of MODS or outcome.

Conclusion

In dogs with sepsis, PCT concentrations at hospital admissions are predictive of organ dysfunction and septic shock. Serial procalcitonin monitoring may offer valuable prognostic information in canine sepsis, wherein early decreases in PCT concentrations are associated with survival.

Electronic supplementary material

The online version of this article (10.1186/s12917-018-1427-y) contains supplementary material, which is available to authorized users.