Dados do Trabalho

Título

DIAGNOSTIC ACCURACY OF TONGUE SWAB TO DETECT MYCOBACTERIUM TUBERCULOSIS IN CHILDREN

Introdução

The development of rapid diagnostic TB tests is recognized as essential to the World Health Organization's (WHO) End TB Strategy to allow early initiation of TB treatment; therefore, WHO endorses using Xpert MTB/RIF Ultra (GeneXpert® Cepheid) as the initial diagnostic test in all children suspected of having TB. In this scenario, the availability of alternative noninvasive sample collection would increase TB testing.

Objetivo (s)

We aimed to describe the diagnostic accuracy of the tongue swab to detect Mycobacterium tuberculosis in children when compared with the sputum sample.

Material e Métodos

Cross-sectional study in 22 Brazilian sites. Children between 6 months to <15 years old were enrolled in two types of health services (hospital and TB clinics) from December 2021 to mid-May 2023. All participants underwent tongue swab and sputum collection to detect Mycobacterium tuberculosis infection using Xpert MTB/RIF Ultra (GeneXpert® Cepheid). The positivity of Xpert MTB/RIF Ultra was defined as detected high, medium, low, very low, or trace. The subjects who could not spit spontaneously had the collection done by induced sputum (IS). Diagnostic accuracy was calculated using the epiR package to estimate sensitivity and specificity values. Exact method was used to calculate 95% confidence intervals for all estimates.

Resultados e Conclusão

Four hundred eighty-six participants were screened, and 406 were included, with a median age of 3.8 (IQR: 1.7-7.0). 358/406 (88.2%) had valid tongue swab and sputum Xpert MTB/RIF Ultra results. 79.3% (284/358) of the participants had IS collection. One tongue swab sample was positive for TB detection (1/358, 0.3%), while in sputum, 15 participants were diagnosed positive for TB (15/358, 4.2%). The child positive for TB in the tongue swab sample presented a very low detection, and in the sputum sample, a high detection of Mycobacterium tuberculosis. Specificity was 100.0% (95%CI, 98.9-100.0), and sensitivity was 6.7% (95%CI, 0.2-31.9). In conclusion, these partial results indicated, at the moment, that the noninvasive tongue swab samples are not as sensible as the sputum sample. However, this is an ongoing study, and more participants will be included.

Palavras-chave

tongue swab, sputum, Mycobacterium tuberculosis, children

Agradecimentos

This work was supported by the PROADI-SUS in collaboration with Hospital Moinhos de Vento (NUP 25000.012788/2021-61).