title: Juvenile household contacts aged 15 or younger of patients with pulmonary TB in the greater metropolitan area of Vitória, Brazil: a cohort study.
abstract: OBJECTIVE
  To compare clinical, radiological and laboratory aspects of household contacts, aged 15 or younger, of patients presenting a positive culture for Mycobacterium tuberculosis.
  
  
  METHODS
  This was a cohort study comparing children and adolescents (< or = 15 years of age) who were household contacts of TB cases presenting positive sputum smear and positive culture results (exposed group, n = 100) or negative sputum smear and positive culture results (unexposed group, n = 55). All of the contacts were evaluated via the TB control program of a university hospital in the city of Vitória, Brazil, between July of 2003 and December of 2006.
  
  
  RESULTS
  Of the 155 minors evaluated, 87 (56.1%) were female and 68 (43.9%) were male. Of those 155, 28 (18%) were aged 5 or younger, 62 (40%) were aged 5-9, and 65 (42%) were aged 10-15. Symptoms of the disease were found in 17 (17%) of the 100 contacts in the exposed group and in 9 (16%) of the 55 in the unexposed group (p = 0.86). Chest X-rays showed alterations in 20 (21%) and 2 (4%) of the contacts in the exposed and unexposed groups, respectively (RR = 6.9; p = 0.004). In the exposed and unexposed groups, respectively, 35 (38%) and 10 (18%) of the contacts presented positive results in the tuberculin skin test (RR = 2.8; p = 0.01). Of the 100 contacts in the exposed group, 5 (5%) were diagnosed with TB, which was not diagnosed in any of those in the unexposed group (p = 0.08).
  
  
  CONCLUSIONS
  Although no significant difference was found between the two groups regarding the incidence of TB, it is of note that there is a greater risk of becoming infected with M. tuberculosis if the bacterial load of the index case is high.
authors.affiliation: Infectious Diseases Center, Health Sciences Center, Federal University of Espírito Santo, Vitória, Brazil. emaciel@ndi.ufes.br
authors.forename: Ethel Leonor Noia
authors.initials: EL
authors.lastname: Maciel
authors.forename: Luiza Werner Heringer
authors.initials: LW
authors.lastname: Vieira
authors.forename: Lucília Pereira Dutra
authors.initials: LP
authors.lastname: Molina
authors.forename: Rosana
authors.initials: R
authors.lastname: Alves
authors.forename: Thiago Nascimento do
authors.initials: TN
authors.lastname: Prado
authors.forename: Reynaldo
authors.initials: R
authors.lastname: Dietze
mesh_terms: D000293:Adolescent; D001938:Brazil; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D016358:Contact Tracing; D005191:Family Characteristics; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D009169:Mycobacterium tuberculosis; D011859:Radiography; D014374:Tuberculin Test; D014397:Tuberculosis, Pulmonary / Q000000981:diagnostic imaging / Q000517:prevention & control / Q000635:transmission*; D014505:Urban Population