title: Comparative study of skin testing with PPD and new tuberculins by the WHO Mantoux test.
abstract: PPD RT 23 tuberculin and two batches of new tuberculin (NT) were tested for concordant skin indurations in the WHO standard Mantoux test in 11- to 13-year-old Finnish school children BCG vaccinated at birth. All were double tested with RT 23 and with either batch T1327 (614 children) or with batch T1456 (312 children) of NT. The results were compared with data available from an earlier study employing RT 23 and T1327 in Ethiopian children, 50/134 of whom had a BCG scar. The mean induration to RT 23 after 72 h was slightly smaller than to the NTs. The individual readings for RT 23 had significant linear correlations with T1327 in Finland (r = 0.77) and in Ethiopia (r = 0.89), and for T1456 (r = 0.83; P < 0.001 for all three). Zero reactions were much fewer to NTs (5.5% to T1327 and 0.3% to T1456) than to RT 23 in Finland (18.2% and 9.3% respectively for the two groups). The results were similar in Ethiopian children. Our results indicate that RT 23 and the two NTs give concordant results, but NTs seem to be more specific, perhaps because they retain more species-specific antigens. Analysis of our results suggests that different peaks in the distribution of reaction sizes were due to responses to different antigens or combinations of antigens, and in the case of the largest reactions, to a different type of immunological response.
authors.affiliation: Department of Paediatrics, University Central Hospital of Turku, Finland.
authors.forename: M
authors.initials: M
authors.lastname: Tala-Heikkilä
authors.forename: E
authors.initials: E
authors.lastname: Lemma
authors.forename: J L
authors.initials: JL
authors.lastname: Stanford
mesh_terms: D000293:Adolescent; D001500:BCG Vaccine; D002648:Child; D005260:Female; D005387:Finland; D006801:Humans; D008297:Male; D014373:Tuberculin; D014374:Tuberculin Test / Q000592:standards*; D014944:World Health Organization
chemical_list: D001500:BCG Vaccine; D014373:Tuberculin