title: The evolving epidemic of drug-resistant tuberculosis among children in Cape Town, South Africa.
abstract: METHODS
  Tygerberg Children's Hospital, Cape Town, South Africa.
  
  
  OBJECTIVE
  To determine the prevalence and trend of drug resistance and human immunodeficiency virus (HIV) co-infection among children with culture-confirmed tuberculosis (TB).
  
  
  METHODS
  Prospective surveillance from  March 2007 to February 2009, compared to three previous surveys (1994-1998, 2003-2005, 2005-2007). Drug susceptibility testing (DST) against isoniazid (INH) and rifampicin (RMP) was performed using genotypic and phenotypic testing. If multidrug-resistant TB (MDR-TB) was detected,  further DST against ethambutol (EMB) and second-line drugs was performed.
  
  
  RESULTS
  A total of 294 children with a median age of 26 months (range 3 days-13 years) were diagnosed with culture-confirmed TB. DST results were available for 292 (99.3%); 41 (14%) were INH-resistant, including  26 (8.9%) with MDR-TB. Four children (1.4%) had RMP monoresistance. EMB resistance was present in 12/24 (50%) MDR-TB cases tested. Two isolates were resistant to ofloxacin; none had extensively drug-resistant TB. Of those tested, 29% (63/217) were HIV-infected. Any resistance to RMP increased  between 1994 and 2009 (P < 0.001), as did RMP monoresistance (P = 0.009) and MDR-TB (P < 0.001). Sensitivity was 87.5% and specificity 100% for genotypic compared to phenotypic testing for INH resistance.
  
  
  CONCLUSIONS
  RMP, and consequently multidrug, resistance  is increasing among children with TB in this setting. EMB resistance is common among children with resistance to RMP and INH.
authors.affiliation: Desmond Tutu TB Centre, Department of Paediatrics and Child Health, Faculty of Health Sciences, Stellenbosch University, Cape Town, South Africa. jseddon@sun.ac.za
authors.forename: J A
authors.initials: JA
authors.lastname: Seddon
authors.forename: A C
authors.initials: AC
authors.lastname: Hesseling
authors.forename: B J
authors.initials: BJ
authors.lastname: Marais
authors.forename: A
authors.initials: A
authors.lastname: Jordaan
authors.forename: T
authors.initials: T
authors.lastname: Victor
authors.forename: H S
authors.initials: HS
authors.lastname: Schaaf
mesh_terms: D017088:AIDS-Related Opportunistic Infections / Q000453:epidemiology*; D000293:Adolescent; D000995:Antitubercular Agents / Q000627:therapeutic use*; D002648:Child; D002675:Child, Preschool; D060085:Coinfection; D058872:Epidemics; D004977:Ethambutol / Q000627:therapeutic use; D005260:Female; D015658:HIV Infections / Q000453:epidemiology*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007538:Isoniazid / Q000627:therapeutic use; D008297:Male; D009169:Mycobacterium tuberculosis / Q000302:isolation & purification*; D015995:Prevalence; D012293:Rifampin / Q000627:therapeutic use; D013019:South Africa / Q000453:epidemiology; D018088:Tuberculosis, Multidrug-Resistant / Q000150:complications / Q000188:drug therapy / Q000453:epidemiology*
chemical_list: D000995:Antitubercular Agents; D004977:Ethambutol; D007538:Isoniazid; D012293:Rifampin