Safety and efficacy of induced sputum in young children hospitalised with suspected pulmonary tuberculosis

Abstract

Background: Induced sputum (IS) is increasingly used to provide specimens for microbiological confirmation of Mycobacterium tuberculosis. The aim of this study was to investigate the safety of and yield from IS in children hospitalised with suspected pulmonary tuberculosis (PTB).

Methods: In a prospective study of children hospitalised with suspected PTB in Cape Town, South Africa, between February 2009 and February 2012, two IS specimens were obtained on consecutive days or at intervals of at least 4 hours. Specimens were investigated for M. tuberculosis using concentrated fluorescent acid-fast smear, liquid culture and GeneXpert(®) MTB/RIF. The safety of IS was assessed by recording clinical signs and symptoms before and for 30 min after sputum induction.

Results: Among 843 children enrolled, at least one IS was performed for 823 (97.6%). The safety of sputum induction was recorded for 690 children (median age 27.3 months [IQR 13.4-64.2]), representing a total of 1270 IS procedures. Of these, 129 (18.7%) had at least one sputum culture positive for M. tuberculosis. Side effects were epistaxis (249, 19.4%) or wheezing (14, 1.1%). The median drop in oxygen saturation during the IS procedure was 1%.

Conclusion: Sputum induction is a safe and useful method for the microbiological confirmation of tuberculosis (TB) in young children.