title: Delayed-type hypersensitivity skin testing predicts progression to AIDS in HIV-infected patients.
abstract: OBJECTIVE
  To evaluate the prognostic significance of cutaneous delayed-type hypersensitivity (DTH) skin testing in persons infected with HIV.
  
  
  METHODS
  Cohort study.
  
  
  METHODS
  United States Air Force (USAF) Medical Center.
  
  
  METHODS
  Consecutive sample of 889 HIV-infected USAF personnel or dependents undergoing their first staging evaluation from 1985 through August 1990 in the USAF HIV Natural History Study.
  
  
  METHODS
  All patients were evaluated with DTH skin testing including purified protein derivative and four control skin test antigens: mumps, candida, tetanus toxoid, and trichophyton. In addition, all patients underwent CD4+ T-cell surface marker determinations. The relation between DTH skin test response at first evaluation and progression to Walter Reed stage 6 (presence of an AIDS-defining opportunistic infection) was evaluated using Kaplan-Meier survival analysis.
  
  
  RESULTS
  Patients with more than 400 CD4+ T cells/mm3 are more likely than those having fewer than 400 CD4+ T cells per mm3 to respond to at least one (94% compared with 67%, P < 0.001) or at least two (86% compared with 45%, P < 0.001) DTH skin tests. Mean CD4 counts are lower for anergic compared with nonanergic patients and for patients responding to a single control skin test compared with those responding to two or more skin tests (P < 0.05). The DTH skin test response at first evaluation was also found to predict progression to AIDS; the relative risk at 5 years of follow-up was 2.5 (95% CI, 1.2 to 5.2) for anergy compared with a single positive skin test and 3.0 (CI, 1.4 to 6.2) for a single compared with two or more skin test responses. The DTH skin test response at first evaluation was a predictor of progression (P < 0.001) when controlling for initial CD4 count and Walter Reed stage in a Cox proportional hazards regression analysis.
  
  
  CONCLUSIONS
  The DTH skin test response, a functional measure of cellular immunity, is an independent predictor of progression to AIDS in persons with HIV.
authors.affiliation: Wilford Hall U.S. Air Force Medical Center, San Antonio, Texas.
authors.forename: S P
authors.initials: SP
authors.lastname: Blatt
authors.forename: C W
authors.initials: CW
authors.lastname: Hendrix
authors.forename: C A
authors.initials: CA
authors.lastname: Butzin
authors.forename: T M
authors.initials: TM
authors.lastname: Freeman
authors.forename: W W
authors.initials: WW
authors.lastname: Ward
authors.forename: R E
authors.initials: RE
authors.lastname: Hensley
authors.forename: G P
authors.initials: GP
authors.lastname: Melcher
authors.forename: D J
authors.initials: DJ
authors.lastname: Donovan
authors.forename: R N
authors.initials: RN
authors.lastname: Boswell
mesh_terms: D000163:Acquired Immunodeficiency Syndrome / Q000276:immunology*; D000293:Adolescent; D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D015496:CD4-Positive T-Lymphocytes; D015331:Cohort Studies; D005260:Female; D015658:HIV Infections / Q000276:immunology*; D006801:Humans; D006968:Hypersensitivity, Delayed / Q000276:immunology; D007958:Leukocyte Count; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D016016:Proportional Hazards Models; D012882:Skin Tests; D016019:Survival Analysis; D014374:Tuberculin Test