Table 1.

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

Characteristic	n
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

* All children born in Finland before September 2006 were supposed to be BCG vaccinated even if this was not mentioned in the record.