Clinical and epidemiological characteristics of severe community-acquired pneumonia in children after introduction of the 10-valent pneumococcal vaccine

What are the risk factors for death among children with pneumonia in low- and middle-income countries? A systematic review

Background

Knowledge of the risk factors for and causes of treatment failure and mortality in childhood pneumonia is important for prevention, diagnosis, and treatment at an individual and population level. This review aimed to identify the most important risk factors for mortality among children aged under ten years with pneumonia.

Methods

We systematically searched MEDLINE, EMBASE, and PubMed for observational and interventional studies reporting risk factors for mortality in children (aged two months to nine years) in low- and middle-income countries (LMICs). We screened articles according to specified inclusion and exclusion criteria, assessed risk of bias using the EPHPP framework, and extracted data on demographic, clinical, and laboratory risk factors for death. We synthesized data descriptively and using Forest plots and did not attempt meta-analysis due to the heterogeneity in study design, definitions, and populations.

Findings

We included 143 studies in this review. Hypoxaemia (low blood oxygen level), decreased conscious state, severe acute malnutrition, and the presence of an underlying chronic condition were the risk factors most strongly and consistently associated with increased mortality in children with pneumonia. Additional important clinical factors that were associated with mortality in the majority of studies included particular clinical signs (cyanosis, pallor, tachypnoea, chest indrawing, convulsions, diarrhoea), chronic comorbidities (anaemia, HIV infection, congenital heart disease, heart failure), as well as other non-severe forms of malnutrition. Important demographic factors associated with mortality in the majority of studies included age <12 months and inadequate immunisation. Important laboratory and investigation findings associated with mortality in the majority of studies included: confirmed Pneumocystis jirovecii pneumonia (PJP), consolidation on chest x-ray, pleural effusion on chest x-ray, and leukopenia. Several other demographic, clinical and laboratory findings were associated with mortality less consistently or in a small numbers of studies.

Conclusions

Risk assessment for children with pneumonia should include routine evaluation for hypoxaemia (pulse oximetry), decreased conscious state (e.g. AVPU), malnutrition (severe, moderate, and stunting), and the presence of an underlying chronic condition as these are strongly and consistently associated with increased mortality. Other potentially useful risk factors include the presence of pallor or anaemia, chest indrawing, young age (<12 months), inadequate immunisation, and leukopenia.

Prevalence of hypoxaemia in children with pneumonia in low-income and middle-income countries: a systematic review and meta-analysis

BACKGROUND

Pneumonia accounts for around 15% of all deaths of children younger than 5 years globally. Most happen in resource-constrained settings and are potentially preventable. Hypoxaemia is one of the strongest predictors of these deaths. We present an updated estimate of hypoxaemia prevalence among children with pneumonia in low-income and middle-income countries.

METHODS

We conducted a systematic review using the following key concepts "children under five years of age" AND "pneumonia" AND "hypoxaemia" AND "low- and middle-income countries" by searching in 11 bibliographic databases and citation indices. We included all articles published between Nov 1, 2008, and Oct 8, 2021, based on observational studies and control arms of randomised and non-randomised controlled trials. We excluded protocol papers, articles reporting hypoxaemia prevalence based on less than 100 pneumonia cases, and articles published before 2008 from the review. Quality appraisal was done with the Joanna Briggs Institute tools. We reported pooled prevalence of hypoxaemia (SpO2 <90%) by classification of clinical severity and by clinical settings by use of the random-effects meta-analysis models. We combined our estimate of the pooled prevalence of pneumonia with a previously published estimate of the number of children admitted to hospital due to pneumonia annually to calculate the total annual number of children admitted to hospital with hypoxaemic pneumonia.

FINDINGS

We identified 2825 unique records from the databases, of which 57 studies met the eligibility criteria: 26 from Africa, 23 from Asia, five from South America, and four from multiple continents. The prevalence of hypoxaemia was 31% (95% CI 26-36; 101 775 children) among all children with WHO-classified pneumonia, 41% (33-49; 30 483 children) among those with very severe or severe pneumonia, and 8% (3-16; 2395 children) among those with non-severe pneumonia. The prevalence was much higher in studies conducted in emergency and inpatient settings than in studies conducted in outpatient settings. In 2019, we estimated that over 7 million children (95% CI 5-8 million) were admitted to hospital with hypoxaemic pneumonia. The studies included in this systematic review had high τ2 (ie, 0·17), indicating a high level of heterogeneity between studies, and a high I2 value (ie, 99·6%), indicating that the heterogeneity was not due to chance. This study is registered with PROSPERO, CRD42019126207.

INTERPRETATION

The high prevalence of hypoxaemia among children with severe pneumonia, particularly among children who have been admitted to hospital, emphasises the importance of overall oxygen security within the health systems of low-income and middle-income countries, particularly in the context of the COVID-19 pandemic. Even among children with non-severe pneumonia that is managed in outpatient and community settings, the high prevalence emphasises the importance of rapid identification of hypoxaemia at the first point of contact and referral for appropriate oxygen therapy.

FUNDING

UK National Institute for Health Research (Global Health Research Unit on Respiratory Health [RESPIRE]; 16/136/109).

The Impact of the Novel Coronavirus on Brazilian PICUs

OBJECTIVES

To study the impact of the coronavirus disease 2019 pandemic, considering the physical distancing and schools closing, on the characteristics of admission and epidemiology on Brazilian PICUs.

DESIGN

Observational, multicenter, time series analysis, of electronic medical records from 15 PICU in Brazil. Data consisted of all March, April, and May PICU admissions from 2017 to 2020.

SETTING

Fifteen private PICUs in Brazil.

PATIENTS

Pediatric patients admitted to the PICU from March to May since 2017.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The period from March 11, 2020, to March 17, 2020, was considered the "intervention point" studied, corresponding to the suspension of school activities and the beginning of physical distancing in Brazil. During the pandemic period studied, there were 28 cases of coronavirus disease 2019 (one death). The mean age was higher (p = 0.000), the length of stay was shorter (p = 0.000), but mortality rates were similar among the periods (p = 0.36). The model estimated a reduction of 1,483 PICU admissions from March 2020 to May 2020. At the end of May, there was an estimated drop of -146.6 bronchiolitis admissions (95% CI, -242.8 to -50.3; p = 0.016); -71 asthma admissions (95% CI, -93.6 to -48.63; p = 0.000); and -59 community-acquired pneumonia admissions (95% CI, -74.7 to -43.3; p = 0.000) per period. The model showed no effect of the "intervention" (physical distancing) on hospitalization rates for epilepsy, diarrhea, sepsis, bacterial meningitis, or surgery when analyzed individually. When assessed together, the model estimated a reduction of 73.6 admissions (95% IC, -132 to -15.2; p = 0.43).

CONCLUSIONS

The coronavirus disease 2019 pandemic strongly affected Brazilian PICUs, reducing admissions, length of stay, and the epidemiological profile. The measures to oppose the coronavirus disease 2019 pandemic may have prevented thousands of PICU hospitalizations across the country.

Compliance with the vaccination schedule in children hospitalized with pneumonia and associated factors

OBJECTIVE:

To verify the adequacy and factors associated with compliance with the immunization schedule (BCG, DTP-Hib, MMR, PCV-10) in children hospitalized with pneumonia at a pediatric referral hospital in Northeast Brazil.

METHODS:

This is a cross-sectional, descriptive study with an analytical component, with a sample of 452 children hospitalized with pneumonia at the Instituto de Medicina Integral Prof. Fernando Figueira, between 2010 and 2013. The inclusion criterion was children aged from one month to less than five years of age with proof in the immunization record. The exclusion criterion was the presence of hospital-acquired pneumonia or concomitant disease. We have evaluated the adequacy of the immunization schedule for the BCG, tetravalent, MMR, and 10-valent pneumococcal conjugate (PCV-10) vaccines. We used the chi-square test and Fisher's exact test followed by multivariate Poisson regression, estimating the crude and adjusted prevalence ratios and respective 95% confidence intervals. The variables with p < 0.20 in the univariate analysis were included in the multivariate analysis.

RESULTS:

There was good adequacy in the immunization schedule, except for PCV-10, which presented a percentage lower than 85%. We have observed an association between adequate compliance with the immunization schedule and education level of the mother (89.9% complete high school), sex of the child (87.2% female), age of the child (94.2% younger than six months), and breastfeeding (84.3% breastfed).

CONCLUSIONS:

Given the high rate of education level of the mother and the high percentage of breastfeeding, we can understand that there is a better understanding of the health of the child by the mothers studied in this study, showing the effectiveness of public policies for infant feeding. However, children did not have good adequacy of the immunization schedule of PCV-10, one of the main vaccines against pneumonia, which can be one of the main factors in the causes of hospitalization, with no influence on the classification of the severity of the disease. In this way, we emphasize that the causes of pneumonia morbidity are not associated with a single factor.