Table 1 Characteristics of children enrolled in the study (n = 99)

Male

63

Age (yrs), median (min-max)

9 (0–18)

BCG vaccinated*

68

BCG non-vaccinated

6

BCG vaccination status unknown

25

Born outside Finland or at least one of the parents is from a country with endemic TB:

57

➢ Somalia (several families)

25

➢ Vietnam

6

➢ Peru (1 family)

4

➢ Russia

4

➢ Kosovo

2

➢ Nigeria

2

➢ Afghanistan, Angola, Azerbadzan, Burma Burundi, Estonia, India, Congo, Sudan, Thailand, Turkey, Uganda

12 (one each)

➢ Siblings who live in Russia

2

HIV infection

2

TST test performed

87

TST not performed

8

Data missing

4

Culture or/and Nucleic acid amplification (NAA) method performed

6

➢ acid fast staining positive

2/6 (also culture pos)

➢ culture positive (M. tuberculosis)

4/6

➢ NAA positive

2/6 (also culture pos)

Radiological examination performed

95

Radiological findings

➢ normal

81/95 (85%)

➢ pulmonary TB

4

➢ enlargement of the hilus zone (Hodgkin lymphoma, TB lymphadenitis, one mild in LTBI, one mild in salmonelosis)

4 (one each)

➢ interstitial changes (vasculitis)

1

➢ pleural effusion (pleuritis and chylothorax)

2

➢ pneumonia

2

➢ bronchoectasia

1

Indications for IGRA-tests

➢ exposure to TB

62

➢ clinical signs compatible with TB

37