The Etiology of Pneumonia From Analysis of Lung Aspirate and Pleural Fluid Samples: Findings From the Pneumonia Etiology Research for Child Health (PERCH) Study

Epidemiology and Diagnostic Accuracy of Respiratory Pathogens in Pediatric Populations: Insights From Global Studies

Lower respiratory tract infections (LRTIs) are the most common cause for going to the doctor's at pediatric age. Respiratory infections are still of interest because they are widespread, significantly impact public health by potentially leading to pandemics, drive antimicrobial resistance through antibiotic misuse, more often spread globally due to traveling, and benefit from ongoing advancements in diagnostics and research for better management. This paper's main aim was to offer a systematic review of the literature published over the last 10 years on the etiology of LRTIs. The search strategy was based on reviewing original articles, systematic reviews, position papers, and guidelines published in MEDLINE, EMBASE, Cochrane Library, and PubMed. The review was previously registered with PROSPERO. The final review included 27 articles that met the eligibility criteria (studies identifying the etiology of inferior respiratory infections in children, according to the WHO definition, published in the last 10 years). Statistical analysis was performed using Microsoft Excel Version 2406 (Microsoft Corporation, Redmond, Washington, USA) and SPSS Statistics V.23 (IBM Corp., Armonk, New York, USA). The total number of patients was 2,193,978. Eight articles focused on children younger than five years, and two included children under the age of two. The results revealed that Mycoplasma pneumoniae and respiratory syncytial virus (RSV) are significant respiratory pathogens with seasonal peaks and age-specific prevalence and that nasopharyngeal aspirates (NPAs) are more reliable than throat swabs for confirming infections due to their higher positive predictive value (PPV). The impact of COVID-19 interventions led to reduced infections from RSV, adenovirus, and influenza viruses, but an increase in rhinovirus post-reopening, with high co-infection rates. Co-infections are common, particularly with pathogens like human bocavirus (HBoV) and RSV, underscoring the need for comprehensive diagnostic approaches. The impact of non-pharmaceutical interventions during the COVID-19 pandemic significantly reduced the prevalence of many respiratory pathogens, except for rhinovirus, which increased post-reopening. Understanding these dynamics is crucial for managing respiratory infections, especially in pediatric populations.

Clinical, Biological, and Radiological Findings and Management of Lower Respiratory Tract Infections in a Tertiary Hospital in Romania

Background Lower respiratory tract infections (LRTIs) remain a significant concern in pediatrics due to their substantial burden among childhood diseases. Romania has recently attained the status of a high-income country. Even though the mortality rate from respiratory diseases has significantly declined from 24.1 per 100,000 individuals in 2000 to 5.3 per 100,000 in 2022, the rate remains notably higher than the European average. Diagnosing LRTI is challenging due to its clinical similarity to noninfectious respiratory illness and frequent false-positive results or incidental findings on microbiologic tests. This often leads to antimicrobial overuse and adverse outcomes. Additionally, antibiotic resistance poses a significant global public health threat. Patients and method We conducted a retrospective analysis of pediatric LRTI cases at a tertiary pediatric center in Romania to evaluate diagnostic testing, imaging use, etiology identification, and treatment approaches. Children under 18, admitted to the Emergency Clinical Hospital for Children in Cluj-Napoca during an eight-month peak respiratory season, were included. Data from electronic medical records were analyzed for demographics, symptoms, physical exams, laboratory data, presence of fever, etiology, treatment, and outcomes. Results In total, 222 children were included in this study, with a median age of 29 months. Among the participants, 58% were male. The average hospital stay was 11 days. The total number of cases was almost equally split between bronchiolitis and pneumonia, with lobar pneumonia accounting for 12% of the included patients. We found two statistically significant correlations between the presence of fever, intercostal retracting, and the subtype of LRTI. An inflammatory response defined as an elevated leucocyte count and elevated C-reactive protein (CRP) was more likely to appear in pneumonia cases than bronchiolitis. From a therapeutic point of view, the prescription of hydrocortisone was statistically linked to bronchiolitis, but its use did not shorten hospitalization time. Conclusion Policy interventions and targeted treatments can reduce LRTI incidence and improve outcomes. Based on our correlations between specific clinical traits and subtypes of LRTIs, the use of assessment scores in children helps predict severe illness and the need for hospitalization. Promoting hygiene, social distancing, and addressing socioeconomic factors are crucial. Larger sample sizes and advanced diagnostics are needed to refine treatment strategies further. Early antibiotic use in children has long-term health implications, including a higher risk of respiratory-caused premature death in adulthood. This emphasizes the need for improved diagnostic processes and specific etiological identification, with metagenomics showing promise in this area.

Alternative Antimicrobial Irrigation Strategies for the Treatment of Infections in Children: A Review of the Existing Literature

As a synergistic treatment approach with systemic antimicrobial therapy or a systemic antibiotic-sparing strategy, the local administration of antimicrobial agents has been proposed as an alternative route for complicated infections. With the rationale of concentrating the active principle in the desired target site, avoiding potentially toxic systemic levels and bypassing anatomical and physiological barriers, local irrigation or infusion of antibiotics may effectively shorten the antimicrobial therapy course and reduce both infection-related and systemic therapy-related complications. Although evidence from the adult population supports its use in selected patients with an acceptable safety profile, data specifically focused on the pediatric population are limited. To provide a rapid and easily accessible tool for clinical practice, we synthesized the most relevant evidence on the use of local antimicrobial agents in common severe infections in children: meningitis, mediastinitis, pleural infections, recurrent urinary infections, and peritonitis. A literature search was performed using predefined combined keywords through an electronic research database (PubMed). Described molecules, dosages, routes, treated age groups, and related efficacy have been summarized for prompt application to clinical practice. It should, however, be noted that the evidence for the pediatric population remains limited, and the local administration of several molecules remains off-label. A careful multidisciplinary and patient-tailored evaluation, as well as a rational use of available guidelines, should always be the basis of clinical decision making in settings where local administration of antibiotics may be considered.

Novel care pathway to optimise antimicrobial prescribing for uncomplicated community-acquired pneumonia: study protocol for a prospective before-after cohort study in the emergency department of a tertiary care Canadian children's hospital

INTRODUCTION

Evidence-based recommendations for paediatric community-acquired pneumonia (CAP) diagnosis and management are needed. Uncomplicated CAP is often caused by respiratory viruses, especially in younger children; these episodes self-resolve without antibiotic treatment. Unfortunately, there are no clinical criteria that reliably discriminate between viral and bacterial disease, and so the majority of children diagnosed with CAP are given antibiotics-even though these will often not help and may cause harm. We have developed a novel care pathway that incorporates point-of-care biomarkers, radiographic patterns, microbiological testing and targeted follow-up. The primary study objective is to determine if the care pathway will be associated with less antimicrobial prescribing.

METHODS AND ANALYSIS

A prospective, before-after, study. Previously well children aged≥6 months presenting to a paediatric emergency department (ED) that have at least one respiratory symptom/sign, receive chest radiography, and are diagnosed with CAP by the ED physician will be eligible. Those with medical comorbidities, recently diagnosed pulmonary infection, or ongoing fever after≥4 days of antimicrobial therapy will be excluded. In the control (before) phase, eligible participants will be managed as per the standard of care. In the intervention (after) phase, eligible participants will be managed as per the novel care pathway. The primary outcome will be the proportion of participants in each phase who receive antimicrobial treatment for CAP. The secondary outcomes include: clinical cure; re-presentation to the ED; hospitalisation; time to resolution of symptoms; drug adverse events; caregiver satisfaction; child absenteeism from daycare/school; and caregiver absenteeism from work.

ETHICS AND DISSEMINATION

All study documentation has been approved by the Hamilton Integrated Research Ethics Board and informed consent will be obtained from all participants. Data from this study will be presented at major conferences and published in peer-reviewed publications to facilitate collaborations with networks of clinicians experienced in the dissemination of clinical guidelines.

TRIAL REGISTRATION NUMBER

NCT05114161.

Nasopharyngeal aspirates in children with severe community-acquired pneumonia collected within 3 days before bronchoscopy can partially reflect the pathogens in bronchoalveolar lavage fluids

BACKGROUND

There is little evidence about consistency between nasopharyngeal and pulmonary pathogens in children with severe pneumonia. This study aims to compare the difference of pathogens between nasopharyngeal aspirates (NPAs) collected before bronchoscopy and bronchoalveolar lavage fluids (BALFs) in children with severe community-acquired pneumonia (SCAP).

METHODS

NPAs and BALFs were collected form pediatric SCAP cases hospitalized from January 2018 to March 2019. NPAs were colleced within 3 days before bronchoscopy. Samples were detected by direct immunofluorescence assay (DFA) for seven respiratory viruses and by routine bacterial culture in the clinical microbiology laboratory. Respiratory syncytial virus (RSV), Adenovirus (ADV), Influenza virus types A, B (IV-A and IV-B), Parainfluenza virus 1-3 (PIV1-3) were detected with a commercial assay. The virological and bacteriological detention results of NPAs were compared with the results of BALFs.

RESULTS

In total 204 cases with mean age of 3.4 ± 2.8 years (IQR, 1 month-14 years) were included in the study. Both NPA and BALF were collected from those cases. The positive rates of pathogen in NPAs and BALFs were 25.0% (51/204) and 36.7% (75/204), respectively (x² = 6.614, P = 0.010). Respiratory viruses were found in 16.1% (33/204) from NPAs and 32.3% (66/204) from BALFs (x² = 14.524, P < 0.001). RSV and ADV were the two most frequent detected viruses in NPAs and BALFs. High consistentcy of pathogens between NPAs and BALFs was observed, and 96.9% (32/33) viruses detected in NPAs were also found in BALFs. While bacteria were isolated from 12.7% (26/204) and 10.7% (22/204) of the two kinds of samples, respectively (x² = 0.378, P = 0.539). In addition, Haemophilus influenzae (HI) was the dominant germ in both samples.

CONCLUSION

The DFA method used to detect seven respiratory viruses from NPAs collected within 3 days before bronchoscopy can partially reflect the pathogens in the lungs in children with SCAP.

Effectiveness of the 10-valent pneumococcal conjugate vaccine on pediatric pneumonia confirmed by ultrasound: a matched case-control study

Background

Bangladesh introduced the 10-valent pneumococcal conjugate vaccine (PCV10) for children aged < 1 year in March 2015. Previous vaccine effectiveness (VE) studies for pneumonia have used invasive pneumococcal disease or chest X-rays. None have used ultrasound. We sought to determine the VE of PCV10 against sonographically-confirmed pneumonia in three subdistrict health complexes in Bangladesh.

Methods

We conducted a matched case–control study between July 2015 and September 2017 in three subdistricts of Sylhet, Bangladesh. Cases were vaccine-eligible children aged 3–35 months with sonographically-confirmed pneumonia, who were matched with two types of controls by age, sex, week of diagnosis, subdistrict health complex (clinic controls) or distance from subdistrict health complex (community controls) and had an illness unlikely due to Streptococcus pneumoniae (clinic controls) or were healthy (community controls). VE was measured using multivariable conditional logistic regression.

Results

We evaluated 8926 children (average age 13.3 months, 58% boys) with clinical pneumonia by ultrasound; 2470 had pneumonia with consolidations ≥ 1 cm; 1893 pneumonia cases were matched with 4238 clinic controls; and 1832 were matched with 3636 community controls. VE increased with the threshold used for consolidation size on ultrasound: the adjusted VE of ≥ 2 doses vs. non-recipients of PCV10 against pneumonia increased from 15.8% (95% CI 1.6–28.0%) for consolidations ≥ 1 cm to 29.6% (12.8–43.2%) for consolidations ≥ 1.5 cm using clinic controls and from 2.7% (− 14.2–17.2%) to 23.5% (4.4–38.8%) using community controls, respectively.

Conclusions

PCV10 was effective at reducing sonographically-confirmed pneumonia in children aged 3–35 months of age when compared to unvaccinated children. VE increased with the threshold used for consolidation size on ultrasound in clinic and community controls alike. This study provides evidence that lung ultrasound is a useful alternative to chest X-ray for case–control studies evaluating the effectiveness of vaccines against pneumonia.

Bacterial etiology of pneumonia in children up to 2 months of age: a systematic review

Background: Following the widespread introduction of childhood pneumococcal conjugate vaccines (PCVs), a significant impact on pneumonia mortality in children under five years of age has been reported. It is still unknown whether PCVs are expected to reduce pneumonia burden in younger children, particularly ≤2 months of age, as current evidence on the role of S. pneumoniae in pneumonia etiology in this age group is scarce. We aimed to summarize the evidence of bacterial etiology of pneumonia in children ≤2 months of age. Methods: We conducted a systematic review considering studies evaluating a variety of syndromes associated with pneumonia, and reporting on laboratory confirmed etiologies, considering any diagnostic method and a variety of clinical specimens.  We searched Medline/PubMed, Embase, WoS, Central and Index Medicus Global published in any language till April 30th, 2021. We included studies addressing the outcomes of interest in children ≤2 months of age and reporting on clinical trials, observational studies, and case series with at least 10 events. Screening of citations and data extraction were conducted in duplicate by independent reviewers, according to the study protocol registered on PROSPERO. Descriptive analyses of the various etiologic agents by syndrome are reported. Results: We identified 3,744 citations, of which 22 publications reporting on 13 studies were included. Study methods varied significantly. Nonetheless, gram positive organisms, in particular S. pneumoniae, were identified as important etiologic agents of pneumonia in children ≤2 months of age. Viral etiologies, in particular Respiratory Syncytial Virus, Rhinovirus, and Influenza were also identified. Conclusions: This review provides the most comprehensive analysis to date of the etiologies of pneumonia in children ≤2 months of age, suggesting that PCV impact is expected to occur in this age group. These results also have major implications for diagnosis and treatment of pneumonia in this age group.

Breiman R, Dowell S, Worku A, Kifle T, Abate E, Dessie Y, Scott JAG. Setting up child health and mortality prevention surveillance in Ethiopia

Background: Mortality rates for children under five years of age, and stillbirth risks, remain high in parts of sub-Saharan Africa and South Asia. The Child Health and Mortality Prevention Surveillance (CHAMPS) network aims to ascertain causes of child death in high child mortality settings (>50 deaths/1000 live-births). We aimed to develop a “greenfield” site for CHAMPS, based in Harar and Kersa, in Eastern Ethiopia. This very high mortality setting (>100 deaths/1000 live-births in Kersa) had limited previous surveillance capacity, weak infrastructure and political instability. Here we describe site development, from conception in 2015 to the end of the first year of recruitment. Methods: We formed a collaboration between Haramaya University and the London School of Hygiene & Tropical Medicine and engaged community, national and international partners to support a new CHAMPS programme. We developed laboratory infrastructure and recruited and trained staff. We established project specific procedures to implement CHAMPS network protocols including; death notifications, clinical and demographic data collection, post-mortem minimally invasive tissue sampling, microbiology and pathology testing, and verbal autopsy. We convened an expert local panel to determine cause-of-death. In partnership with the Ethiopian Public Health Institute we developed strategies to improve child and maternal health. Results: Despite considerable challenge, with financial support, personal commitment, and effective partnership, we successfully initiated CHAMPS. One year into recruitment (February 2020), we had received 1173 unique death notifications, investigated 59/99 MITS-eligible cases within the demographic surveillance site, and assigned an underlying and immediate cause of death to 53 children. Conclusions: The most valuable data for global health policy are from high-mortality settings, but initiating CHAMPS has required considerable resource. To further leverage this investment, we need strong, sustained, local research leadership, and to broaden the scientific remit. To support this, we have set up a new collaboration, the “Hararghe Health Research Partnership”.

Breiman R, Dowell S, Worku A, Kifle T, Abate E, Dessie Y, Scott JAG. Setting up child health and mortality prevention surveillance in Ethiopia

Background: Mortality rates for children under five years of age, and stillbirth risks, remain high in parts of sub-Saharan Africa and South Asia. The Child Health and Mortality Prevention Surveillance (CHAMPS) network aims to ascertain causes of child death in high child mortality settings (>50 deaths/1000 live-births). We aimed to develop a “greenfield” site for CHAMPS, based in Harar and Kersa, in Eastern Ethiopia. This very high mortality setting (>100 deaths/1000 live-births in Kersa) had limited previous surveillance capacity, weak infrastructure and political instability. Here we describe site development, from conception in 2015 to the end of the first year of recruitment. Methods: We formed a collaboration between Haramaya University and the London School of Hygiene & Tropical Medicine and engaged community, national and international partners to support a new CHAMPS programme. We developed laboratory infrastructure and recruited and trained staff. We established project specific procedures to implement CHAMPS network protocols including; death notifications, clinical and demographic data collection, post-mortem minimally invasive tissue sampling, microbiology and pathology testing, and verbal autopsy. We convened an expert local panel to determine cause-of-death. In partnership with the Ethiopian Public Health Institute we developed strategies to improve child and maternal health. Results: Despite considerable challenge, with financial support, personal commitment and effective partnership, we successfully initiated CHAMPS. One year into recruitment (February 2020), we had received 1173 unique death notifications, investigated 59/99 MITS-eligible cases within the demographic surveillance site, and assigned an underlying and immediate cause of death to 53 children. Conclusions: The most valuable data for global health policy are from high mortality settings, but initiating CHAMPS has required considerable resource. To further leverage this investment, we need strong local research capacity and to broaden the scientific remit. To support this, we have set up a new collaboration, the “Hararghe Health Research Partnership”.

Assessment of nasopharyngeal Streptococcus pneumoniae colonization does not permit discrimination between Canadian children with viral and bacterial respiratory infection: a matched-cohort cross-sectional study

Background

Readily-available diagnostics do not reliably discriminate between viral and bacterial pediatric uncomplicated pneumonia, both of which are common. Some have suggested that assessment of pneumococcal carriage could be used to identify those children with bacterial pneumonia. The objective of this study was to determine if nasopharyngeal pneumococcal colonization patterns differed between children with definite viral disease, definite bacterial disease, and respiratory disease of indeterminate etiology.

Methods

Three groups of subjects were recruited: children with critical respiratory illness, previously healthy children with respiratory illness admitted to the ward, and previously healthy children diagnosed in the emergency department with non-severe pneumonia. Subjects were categorized as follows: a) viral infection syndrome (eg. bronchiolitis), b) bacterial infection syndrome (ie. pneumonia complicated by effusion/empyema), or c) ‘indeterminate’ pneumonia. Subjects’ nasopharyngeal swabs underwent quantitative PCR testing for S. pneumoniae. Associations between categorical variables were determined with Fisher’s exact, chi-square, or logistic regression, as appropriate. Associations between quantitative genomic load and categorical variables was determined by linear regression.

Results

There were 206 children in Group 1, 122 children in Group 2, and 179 children in Group 3. Only a minority (227/507, 45%) had detectable pneumococcal carriage; in those subjects, there was no association of quantitative genomic load with age, recruitment group, or disease category. In multivariate logistic regression, pneumococcal colonization > 3 log copies/mL was associated with younger age and recruitment group, but not with disease category.

Conclusions

The nasopharyngeal S. pneumoniae colonization patterns of subjects with definite viral infection were very similar to colonization patterns of those with definite bacterial infection or indeterminate pneumonia. Assessment and quantification of nasopharyngeal pneumococcal colonization does not therefore appear useful to discriminate between acute viral and bacterial respiratory disease; consequently, this diagnostic testing is unlikely to reliably determine which children with indeterminate pneumonia have a bacterial etiology and/or require antibiotic treatment.

Epidemiology of Hypoxic Community-Acquired Pneumonia in Children Under 5 Years of Age: An Observational Study in Northern India

BACKGROUND

Community-acquired pneumonia (CAP) is the leading cause of under-five mortality in India. An increased risk of mortality has been reported in cases of hypoxic pneumonia.

METHODS

The primary objective of this study was to assess the proportion of children aged 2-59 months, hospitalized with hypoxic CAP, as well as socio-demographic, clinical, and radiological features associated with it. The secondary objective was to determine the risk of mortality among hospitalized cases of hypoxic CAP. This prospective, observational study was conducted in four districts of Northern India, between January 2015 and April 2021. A hospital-based surveillance network was established. Inclusion criteria were as follows: (a) child between 2 and 59 months, (b) hospitalization with symptoms of WHO-defined CAP, (c) resident of project district, (d) illness of <14 days, and (e) child had neither been hospitalized for this illness nor recruited previously. Children whose chest x-rays (CXRs) were either unavailable/un-interpretable and those that received any dose of pneumococcal conjugate vaccine-13 were excluded. Hypoxic pneumonia was defined as oxygen saturation <90% on pulse oximetry or requiring oxygen supplementation during hospital stay.

RESULTS

During the study period, 71.9% (7,196/10,006) children of severe pneumonia were eligible for inclusion, of whom 35.9% (2,580/7,196) were having hypoxic pneumonia. Female gender and use of biomass fuel for cooking increased the odds of hypoxic CAP. Clinical factors like wheezing, pallor, tachypnea, low pulse volume, presence of comorbidity, general danger signs, severe malnutrition, and radiological finding of primary end-point pneumonia ± other infiltrates (PEP±OI) also increased the odds of hypoxic CAP in a conditional logistic regression model. Adjusted odds ratio for mortality with hypoxia was 2.36 (95% CI: 1.42-3.92).

CONCLUSION

Almost one-third of cases hospitalized with severe CAP had hypoxia, which increased chances of mortality. Besides known danger signs, certain newer clinical signs such as pallor and wheezing as well as PEP+OI were associated with hypoxic CAP. Therefore, objective assessment of oxygen saturation must be done by pulse oximetry in all cases of CAP at the time of diagnosis.