title: Correlation between CD4+ lymphocyte counts, concurrent antigen skin test and tuberculin skin test reactivity in human immunodeficiency virus type 1-infected and -uninfected children with tuberculosis.
abstract: BACKGROUND
  HIV-infected children are at high risk of developing tuberculosis after infection by Mycobacterium tuberculosis. Emphasis is placed on tuberculin skin testing (TST) for diagnosing tuberculosis in children; however, its value in HIV-infected children is controversial.
  
  
  OBJECTIVE
  To determine whether concurrent antigen testing and/or CD4+ lymphocyte counts help in the interpretation of the TST in children with tuberculosis.
  
  
  METHODS
  Children eligible for the study were diagnosed as having tuberculosis on clinical criteria. CD4+ lymphocyte counts and delayed-type hypersensitivity (DTH) test, using the CMI Multitest were performed when tuberculosis was diagnosed.
  
  
  RESULTS
  One hundred thirty children were enrolled. Tuberculin reactivity was lower in HIV-infected children at all cutoff levels than in HIV-uninfected children (P < 0.0001). The positive predictive value of normal CD4+ lymphocyte counts in predicting tuberculin reactions of > or =5 mm (in HIV-1-infected) and > or =10 mm (in HIV-uninfected patients) were 50 and 80.3%, respectively (P < 0.0001). An intact DTH reaction to the CMI Multitest in predicting reactions of > or =5 mm and > or =10 mm to tuberculin in HIV-infected and -uninfected children were 55 and 76%, respectively (P < 0.001). Kwashiorkor was responsible for 53.3% of false-negative TST in HIV-uninfected children with normal CD4+ lymphocyte counts.
  
  
  CONCLUSIONS
  TST is of limited value as an adjunct in diagnosing tuberculosis in HIV-infected children. CD4+ lymphocyte counts and concurrent DTH testing are not useful for predicting tuberculin reactivity in HIV-infected patients with tuberculosis.
authors.affiliation: Department of Paediatrics, University of the Witwatersrand, Johannesburg, South Africa.
authors.forename: S A
authors.initials: SA
authors.lastname: Madhi
authors.forename: G E
authors.initials: GE
authors.lastname: Gray
authors.forename: R E
authors.initials: RE
authors.lastname: Huebner
authors.forename: G
authors.initials: G
authors.lastname: Sherman
authors.forename: D
authors.initials: D
authors.lastname: McKinnon
authors.forename: J M
authors.initials: JM
authors.lastname: Pettifor
mesh_terms: D017088:AIDS-Related Opportunistic Infections / Q000175:diagnosis* / Q000276:immunology; D018791:CD4 Lymphocyte Count; D002648:Child; D002675:Child, Preschool; D017449:Dermatitis, Allergic Contact / Q000209:etiology / Q000276:immunology*; D015658:HIV Infections / Q000150:complications / Q000276:immunology; D015497:HIV-1 / Q000302:isolation & purification; D006801:Humans; D007223:Infant; D011446:Prospective Studies; D012882:Skin Tests; D014374:Tuberculin Test / Q000009:adverse effects; D014376:Tuberculosis / Q000150:complications / Q000175:diagnosis* / Q000276:immunology