[The use of chest X-rays for surveillance of bacterial pneumonias in children in Latin America]

Burden of Culture-Confirmed Pediatric Pneumococcal Pneumonia in Latin America and the Caribbean: A Systematic Review and Meta-Analysis

BACKGROUND

Pneumococcal pneumonia (PP) causes almost one in five deaths in children younger than 5 years worldwide. In Latin America and the Caribbean (LAC), pneumonia causes 14% of all deaths. Although pneumococcal disease is a vaccine-preventable disease that accounts for a significant proportion of this burden, the decision-making process to introduce pneumococcal conjugate vaccines in official schedules is still complex in LAC. Confirmed PP cases and epidemiology are the basis for broader projections.

OBJECTIVE

To gather all the information available in the LAC region to assist decision makers.

METHODS

We performed a systematic review of studies of consolidating and culture-confirmed pediatric PP in LAC (2000-2016) using a generic academic Internet search and search engines without language restrictions. Pairs of reviewers independently selected and assessed the studies' methodological quality. We analyzed meta-information on pneumococcal serotypes available from the SIREVA laboratory-based surveillance system.

RESULTS

A total of 35 out of 750 initially identified studies were included. In the age group between 0 and 59 years, the incidence of culture-confirmed PP ranged from 10.2 to 43.0/100,000 children, with a pooled incidence of 20.4/100,000 children (95% confidence interval 0.0-123.2). Mortality ranged from 0.4 to 5.7/100,000 children, and the pooled mortality was 2.9/100,000 children (95% confidence interval 0.3-8.2). The pooled serotype distribution from surveillance data showed that serotypes 14, 1, and 6B were the most frequent serotypes in LAC, all included in licensed vaccines.

CONCLUSIONS

Studies on confirmed pediatric PP were scarce in LAC in 2000 to 2016. Epidemiology indicators and health resource use are still poorly defined.

Pneumococcal pneumonia in hospitalized Uruguayan children and potential prevention with different vaccine formulations

OBJECTIVES

To provide information on pneumococcal pneumonias, on their associated serotypes, and to estimate the coverage potentially afforded by antipneumococcal vaccines.

STUDY DESIGN

A retrospective study (2000 to 2004) was performed of patients with pneumococcal pneumonia aged 0 to 14 years admitted to the National Reference Children's Hospital in Uruguay. Selected clinical data, radiographic interpretation, and microbiologic reports were obtained for analysis.

RESULTS

Of 410 enrolled patients, 384 had consolidated pneumonia/pleural effusion and 26 had infiltrates without consolidation: Pneumococcus was identified in blood or in pleural fluid of 387 patients; 21 serotypes were identified. The most frequent serotypes in decreasing order were serotypes 14, 1, 5, 3, 9V, 6B, and 7F. Forty-eight percent of invasive Streptococcus pneumoniae isolates were obtained from children younger than 24 months. For this group, the 7-valent vaccine would cover 60%, but a 10-valent vaccine would cover 83.8%.

CONCLUSIONS

This study provides information on pneumonia of proven S. pneumoniae causes and their associated serotypes, enabling estimation of potential effect of pneumococcal conjugate vaccines.

A population-based assessment of the disease burden of consolidated pneumonia in hospitalized children under five years of age

BACKGROUND

Population-based studies on childhood community-acquired pneumonia are scarce in Latin America. Pneumococcal epidemiology is poorly defined, hence the World Health Organization recommended standardized chest radiograph interpretation to improve the approach to bacterial pneumonia. Therefore, our study aimed to estimate the burden of pneumonia in hospitalized children.

METHODS

A three-year surveillance study was carried out in four hospitals covering a population of 229,128 inhabitants of whom 10.2% were under five years of age. Clinical records and digitization of their chest radiographs were obtained. A pediatrician and a pediatric radiologist blinded to the clinical diagnosis interpreted the digital images.

RESULTS

Of 2034 patients, 826 (40.6%) had consolidated pneumonia, 941 (46.3%) had non-consolidated pneumonia, and 267 (13.1%) had no pneumonia. Children under two years of age predominated (66.9%). The average annual incidence rate for consolidated pneumonia over the three-year study period was 1175/10(5). Eighteen invasive Streptococcus pneumoniae were isolated from patients with consolidated pneumonia and two from those with non-consolidated pneumonia. Respiratory syncytial virus was evenly distributed between both X-ray groups.

CONCLUSIONS

Patients younger than two years of age predominated, being the main targets for anti-pneumococcal conjugated vaccines. Incidence rates provided evidence of the burden of consolidated pneumonia for childhood, estimating the potential benefits of vaccination.

Diagnosing pneumonia in rural Thailand: Digital cameras versus film digitizers for chest radiograph teleradiology

Background

Accurate surveillance for pneumonia requires standardized classification of chest radiographs. Digital imaging permits rapid electronic transfer of data to radiologists, and recent improvements in digital camera technology present high quality, yet cheaper, options.

Methods

We evaluated the comparative utility of digital camera versus film digitizer in capturing chest radiographs in a pneumonia surveillance system in rural Thailand using a panel of radiologists; the gold standard was the hard-copy radiograph. We calculated sensitivity and specificity and conducted a receiver operator characteristics (ROC) analysis.

Results

Of the 192 radiographs from patients with clinical pneumonia, 166 (86%) were classified as pneumonia on the hard copies. Sensitivity and specificity for identifying pneumonia were 89% and 73% for the camera and 90% and 65% for the digitizer. In the ROC analysis, there was no statistically significant difference in the area under the curve (camera, 0.86; film digitizer, 0.91, p = 0.29). The digital camera set cost $965 compared to $3000 for the film digitizer.

Conclusion

Detection of pneumonia was not measurably compromised by using digital cameras compared with film digitizers. The 3-fold lower cost of the digital camera makes this technology an affordable and widely accessible alternative for surveillance systems, vaccine trials, and perhaps clinical use.