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. 2018 Nov 15;18(1):574.
doi: 10.1186/s12879-018-3483-0.

Feasibility of the string test for tuberculosis diagnosis in children between 4 and 14 years old

Karla T Tafur  1 , Julia Coit  2 , Segundo R Leon  2 , Cynthia Pinedo  3 , Silvia S Chiang  4   5 , Carmen Contreras  3 , Roger Calderon  3 , Milagros J Mendoza  3 , Leonid Lecca  3   2 , Molly F Franke  2
Affiliations

Feasibility of the string test for tuberculosis diagnosis in children between 4 and 14 years old

Karla T Tafur et al. BMC Infect Dis. .

Abstract

Background: The enteric string test can be used to obtain a specimen for microbiological confirmation of tuberculosis in children, but it is not widely used for this. The aim of this analysis to evaluate this approach in children with tuberculosis symptoms.

Methods: We conducted a cross-sectional study to assess children's ability to complete the test (feasibility), and self-reported pain (tolerability). We examined caregivers' and children's willingness to repeat the procedure (acceptability) and described the diagnostic yield of cultures for diagnostic tools. We stratified estimates by age and compared metrics to those derived for gastric aspirate (GA).

Results: Among 148 children who attempted the string test, 34% successfully swallowed the capsule. Feasibility was higher among children aged 11-14 than in children 4-10 years (83% vs 22% respectively, p < 0.0001). The string test was better tolerated than GA in both age groups; however, guardians and older children reported higher rates of willingness to repeat GA than the string test (86% vs. 58% in children; 100% vs. 83% in guardians). In 9 children with a positive sputum culture, 6 had a positive string culture. The one children with a positive gastric aspirate culture also had a positive string culture.

Conclusion: Although the string test was generally tolerable and accepted by children and caregivers; feasibility in young children was low. Reducing the capsule size may improve test success rates in younger children.

Keywords: Feasibility; Gastric aspirate; Pediatric; Peru; Tolerability.

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Conflict of interest statement

Ethics approval and consent to participate

The study was approved by the Ethics Committee of Peru’s National Institute of Health and the Office of Human Research Administration at the Harvard Medical School. Guardians provided written informed consent, and children eight years of age and older provided written informed assent.

Competing interests

The authors declare that they have no competing interests.

Publisher’s Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Figures

Fig. 1
Fig. 1
Self-reported pain levels by children during and after the string test and gastric aspiration, by age group
See this image and copyright information in PMC

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