4.1 Introduction

In children, defined in this chapter as patients under 10 years, tuberculosis (TB), pulmonary (PTB) and extrapulmonary (EPTB), is a significant cause of morbidity and mortality.

Globally, WHO estimates that more than one million children develop active TB every year [1] Citation 1. World Health Organization. WHO consolidated guidelines on tuberculosis. Module 5: management of tuberculosis in children and adolescents. Geneva: World Health Organization; 2022.
https://apps.who.int/iris/rest/bitstreams/1414329/retrieve  and that 60% of TB cases in children are not diagnosed or not reported [2] Citation 2. World Health Organization. Global Tuberculosis Report 2021. Geneva: World Health Organization; 2021.
https://apps.who.int/iris/rest/bitstreams/1379788/retrieve .

After exposure, the risk of TB infection and progression to active TB is high in children under 5 years [3] Citation 3. World Health Organization. WHO operational handbook on tuberculosis. Module 5: management of tuberculosis in children and adolescents. Geneva: World Health Organization; 2022.
https://apps.who.int/iris/rest/bitstreams/1414333/retrieve .

Progression to active TB is rapid (within 12 months) in children under 2 years [4] Citation 4. Marais BJ, Gie RP, Schaaf HS, et al. The natural history of childhood intra-thoracic tuberculosis: a critical review of literature from the pre-chemotherapy era. Int J Tuberc Lung Dis. 2004;8(4):392-402.
https://www.ingentaconnect.com/content/iuatld/ijtld/2004/00000008/00000004/art00002;jsessionid=6n3iklj7549s8.x-ic-live-03# .

HIV infection is a significant risk factor for developing TB in children under 1 year [5] Citation 5. Hesseling AC, Cotton MF, Jennings T, Whitelaw A, Johnson LF, Eley B, Roux P, Godfrey-Faussett P, Schaaf HS. High incidence of tuberculosis among HIV-infected infants: evidence from a South African population-based study highlights the need for improved tuberculosis control strategies. Clin Infect Dis. 2009 Jan 1;48(1):108-14.
https://doi.org/10.1086/595012 .

The risk of miliary TB and EPTB, including severe forms such as TB meningitis, is higher in children under 5 years and in immunocompromised children [3] Citation 3. World Health Organization. WHO operational handbook on tuberculosis. Module 5: management of tuberculosis in children and adolescents. Geneva: World Health Organization; 2022.
https://apps.who.int/iris/rest/bitstreams/1414333/retrieve . The most common forms of EPTB are lymph node TB and pleural TB (pleural effusion). Osteoarticular TB represents 1 to 2% of TB in children [4] Citation 4. Marais BJ, Gie RP, Schaaf HS, et al. The natural history of childhood intra-thoracic tuberculosis: a critical review of literature from the pre-chemotherapy era. Int J Tuberc Lung Dis. 2004;8(4):392-402.
https://www.ingentaconnect.com/content/iuatld/ijtld/2004/00000008/00000004/art00002;jsessionid=6n3iklj7549s8.x-ic-live-03# .

The risk of death from TB is higher in children under 2 years and children with HIV infection or severe acute malnutrition (SAM) [3] Citation 3. World Health Organization. WHO operational handbook on tuberculosis. Module 5: management of tuberculosis in children and adolescents. Geneva: World Health Organization; 2022.
https://apps.who.int/iris/rest/bitstreams/1414333/retrieve . Almost all deaths due to TB in children occur in those not receiving TB treatment, and in the vast majority of cases, in children under 5 years [6] Citation 6. Dodd PJ, Yuen CM, Sismanidis C, Seddon JA, Jenkins HE. The global burden of tuberculosis mortality in children: a mathematical modelling study. Lancet Glob Health. 2017 Sep;5(9):e898-e906.
https://doi.org/10.1016/S2214-109X(17)30289-9 .

TB treatment should not be delayed if investigations, or results of investigations, are not immediately available in children at high risk of TB or death from TB.

Children often have the same resistance profile as the index case, i.e. the person who is the presumed source of the infection. If the resistance profile is not available for the child, the resistance profile of the index case should be taken into account for the child’s TB treatment.

Children are not considered infectious unless they have extensive lung involvement and/or cavitary PTB or positive smear microscopy.