Cell-mediated immunity assessed by skin testing (Multitest). I. Normal values in healthy Danish adults

The Multitest CMI system consists of a disposable multiple puncture device that simultaneously applies seven standardized recall antigens for assessment of cell-mediated immunity (CMI). The seven antigens included were toxoid from Clostridium tetani and Corynebacterium diphtheriae, tuberculin, plus antigens from streptococcus (group C), Candida albicans, Trichophyton mentagrophytes, and Proteus mirabilis. A population of 352 healthy Danish adults, aged between 17 and 90 years, was tested to determine the incidence and size of delayed-type hypersensitivity (DTH) responses. All but six healthy adults (98%) responded to one or more antigens, the median number of positive responses being four in males and three in females. The incidence of positive responses ranged from 91% for tuberculin to 11% for trichophyton. The number of positive responses declined with age, being somewhat faster in females than males. Six of the seven antigen response rates were significantly lower in the over 65-years-olds, the only exception being trichophyton, and for four of the seven antigens significantly lower in females compared to males. When correlated to age and sex no major differences were found with regard to the size of response to the seven antigens except that the tuberculin response was larger in males. A scoring system based on both number and size of positive responses revealed significant age and sex related differences. The median "score" in 17-65-year-old males and females were, respectively, 17 mm and 14 mm compared to 13 mm and 8 mm in those over 65 years old (P less than 0.001 for both comparisons).