Table 2.

Recommendations for the use of Tuberculin Skill Test (TST) and Interferon-gamma Release Assay (IGRA) in children

	TST alone	IGRA alone	both TST and IGRA
WHO [6]	• Any child, irrespective of HIV status, in low and middle-income countries
NICE [22]	• Children younger than 5 years	• BCG vaccinated children (> 5 years of age) • Children > 5 years of age, in an outbreak situation	• Children > 5 years of age whose TST is positive
American [12,16]	• Children younger than 5 years • Before initiation of immunosuppressive therapy	• BCG vaccinated children (> 5 years of age) • Children > 5 years of age who are unlikely to return for TST reading • Before starting immunosuppressive therapy	• The initial and repeat IGRA are indeterminate • The initial test (TST or IGRA) is negative and: - clinical suspicion for TB disease is moderate to high - risk of progression and poor outcome is high • The initial TST is positive and: - Children > 5 years of age who have received BCG vaccine - Non-tuberculous mycobacterial disease is suspected - Additional evidence are needed to increase compliance
European [19]	• Children younger than 5 years • Children > 5 years who are: - not HIV-infected - not BCG vaccinated	• BCG vaccinated children (> 5 years of age)	• HIV-infected children • Before starting immunosuppressive therapy (anti-TNFalfa inhibitor therapy)
Spanish [23]	• Any child		• The initial TST is negative and: - Immunocompromised children - High risk of infection, of progression to disease and of a poor outcome • The initial TST is positive and: - BCG vaccinated children - Risk factors are negative
Canadian [31]	• Whenever it is planned to repeat the test later to assess risk of new infection (i.e. conversions)	• People who have received BCG vaccination • People from groups that historically have poor rates of return for TST reading.	• High risk of infection, of progression to disease and of a poor outcome • The initial and repeat IGRA are indeterminate

Note. WHO: World Health Organization; BCG: Bacille Calmette-Guèrin