title: High tuberculosis prevalence in children exposed at home to drug-resistant tuberculosis.
abstract: METHODS
  Urban Karachi, Pakistan.
  
  
  OBJECTIVE
  To describe the yield of a contact investigation protocol implemented among children living with drug-resistant tuberculosis (DR-TB) patients.
  
  
  METHODS
  We implemented a contact investigation protocol in households of DR-TB patients treated at the Indus Hospital, Karachi, between January 2008 and April 2011. This included a detailed history and physical examination, tuberculin skin test, chest radiograph, smear microscopy and culture of sputum or gastric aspirate specimens, and drug susceptibility testing. Treatment supporters who visited DR-TB patients at home referred all child contacts for baseline evaluation and performed monthly assessments. We evaluated two age groups: 1) children aged <5 years, and 2) those aged 5-14 years.
  
  
  RESULTS
  Among 133 children aged <15 years in 40 households, 40.4% (51/125) were moderately to severely underweight (weight-for-age Z-score <-2). Overall, 7.5% (10/133) had TB disease. This proportion was 6.5% (2/31) in those aged <5 years and 7.8% (8/102) in those aged 5-14 years. Seven (7/10) were smear-positive, and 4/10 had culture-confirmed multidrug-resistant Mycobacterium tuberculosis
  
  
  CONCLUSIONS
  We detected a high prevalence of TB in children who live with DR-TB patients, regardless of the age of the child. Child contacts of DR-TB patients are a high-yield population for detecting TB cases.
authors.affiliation: Indus Hospital Research Center, Korangi Crossing, Karachi, Pakistan.
authors.forename: F
authors.initials: F
authors.lastname: Amanullah
authors.affiliation: Interactive Research and Development, Karachi, Pakistan.
authors.forename: M
authors.initials: M
authors.lastname: Ashfaq
authors.affiliation: Interactive Research and Development, Karachi, Pakistan.
authors.forename: S
authors.initials: S
authors.lastname: Khowaja
authors.affiliation: Interactive Research and Development, Karachi, Pakistan.
authors.forename: A
authors.initials: A
authors.lastname: Parekh
authors.affiliation: Indus Hospital Research Center, Korangi Crossing, Karachi, Pakistan.
authors.forename: N
authors.initials: N
authors.lastname: Salahuddin
authors.affiliation: Interactive Research and Development, Karachi, Pakistan.
authors.forename: I
authors.initials: I
authors.lastname: Lotia-Farrukh
authors.affiliation: Interactive Research and Development, Karachi, Pakistan.
authors.forename: A J
authors.initials: AJ
authors.lastname: Khan
authors.affiliation: Department of Global Health and Social Medicine, Harvard Medical School, Boston, Massachusetts, USA.
authors.forename: M C
authors.initials: MC
authors.lastname: Becerra
mesh_terms: D000293:Adolescent; D000367:Age Factors; D000995:Antitubercular Agents / Q000627:therapeutic use; D002648:Child; D002675:Child, Preschool; D016358:Contact Tracing; D024901:Drug Resistance, Multiple, Bacterial; D005260:Female; D006801:Humans; D008297:Male; D008826:Microbial Sensitivity Tests; D010154:Pakistan / Q000453:epidemiology; D010808:Physical Examination; D011237:Predictive Value of Tests; D015995:Prevalence; D011446:Prospective Studies; D012111:Residence Characteristics; D013183:Sputum / Q000382:microbiology; D013997:Time Factors; D018088:Tuberculosis, Multidrug-Resistant / Q000175:diagnosis / Q000188:drug therapy / Q000453:epidemiology* / Q000635:transmission*
chemical_list: D000995:Antitubercular Agents