A Prospective Study of the Prevalence of Tuberculosis and Bacteraemia in Bangladeshi Children with Severe Malnutrition and Pneumonia Including an Evaluation of Xpert MTB/RIF Assay

Abstract

BackgroundSevere malnutrition is a risk factor for pneumonia due to a wide range of pathogens but aetiological data are limited and the role of Mycobacterium tuberculosis is uncertain.MethodsWe prospectively investigated severely malnourished young children (<5 years) with radiological pneumonia admitted over a 15-month period. Investigations included blood culture, sputa for microscopy and mycobacterial culture. Xpert MTB/RIF assay was introduced during the study. Study children were followed for 12 weeks following their discharge from the hospital.Results405 eligible children were enrolled, with a median age of 10 months. Bacterial pathogens were isolated from blood culture in 18 (4.4%) children, of which 72% were Gram negatives. Tuberculosis was confirmed microbiologically in 7% (27/396) of children that provided sputum - 10 by culture, 21 by Xpert MTB/RIF assay, and 4 by both tests. The diagnostic yield from induced sputum was 6% compared to 3.5% from gastric aspirate. Sixty (16%) additional children had tuberculosis diagnosed clinically that was not microbiologically confirmed. Most confirmed tuberculosis cases did not have a positive contact history or positive tuberculin test. The sensitivity and specificity of Xpert MTB/RIF assay compared to culture was 67% (95% CI: 24–94) and 92% (95% CI: 87–95) respectively. Overall case-fatality rate was 17% and half of the deaths occurred in home following discharge from the hospital.Conclusion and SignificanceTB was common in severely malnourished Bangladeshi children with pneumonia. X-pert MTB/RIF assay provided higher case detection rate compared to sputum microscopy and culture. The high mortality among the study children underscores the need for further research aimed at improved case detection and management for better outcomes.

Xpert MTB/RIF assay for the diagnosis of pulmonary tuberculosis in children: A systematic review and meta-analysis

“…We selected 15 studies for inclusion (figure 1). [12][13][14][15][16][17][18][19][20][21][22][23][24][25] Five studies were done in low-income countries, two in lower middle-income, six in upper middle-income, and two in high-income countries (table 1). 26 12 studies were done at tertiary, university, or research facilities.…”

Xpert MTB/RIF assay for the diagnosis of pulmonary tuberculosis in children: A systematic review and meta-analysis

“…Investigators of some studies collected the same specimen type from all children, whereas others collected different types of specimens from different subgroups of children-eg, expectorated sputum in older children and induced sputum or gastric fluid (gastric lavage) in younger children. Investigators of four studies 18,20,23 collected different types of specimen in each child (Walters E, Desmond Tutu TB Centre, South Africa, personal communication; appendix). Researchers had heterogeneous approaches to inclusion criteria and definition of presumed tuberculosis, the number of specimens collected and cultures needed per child to confirm tuberculosis, and the definition of clinical tuberculosis in culture-negative children (table 2; appendix).…”

“…Studies using broader definitions included laboratory-based studies with no clinical inclusion criteria and hospital-based studies including populations such as severely malnourished children, in which tuberculosis is one of the differential diagnoses. 19,20 The yield of Xpert in these groups was very low and shows the association between disease prevalence and test accuracy.…”

Comparative Study of Nutritional Status of Children (02-24 Months) with Acute Bronchiolitis and Pneumonia

“…Bacterial infection in children more likely to be associated with pneumonia compared to bronchiolitis 20 . Moreover, children with poor nutritional status more likely to be associated with bacterial pneumonia 21,22 . This explains our observation of association of pneumonia with poor nutritional status compared to bronchiolitis.…”