Anergy testing in nursing home residents.

Abstract

Delayed cutaneous hypersensitivity (DCH) testing is commonly used to determine exposure to Mycobacterium tuberculosis and in the evaluation of cellular-mediated immunity. Many reports indicate that anergy to ubiquitous antigens is common in the elderly. Recent studies suggest that anergy in the aged is not common when five or more antigens are used. Because it is often difficult to purchase singularly or apply a larger number of quality DCH antigens, we investigated the usefulness of the Multitest CMI in 29 nursing home residents with chronic diseases. This device simultaneously applies seven skin test antigens and a negative control. Ten young healthy subjects served as controls. DCH reactions were scored based on the sum of induration and total number of positive responses. Although elderly subjects had significantly lower scores than the young subjects, only 7% of elderly subjects were anergic. Our data indicate that the Multitest CMI is a highly effective device to test for DCH in geriatric subjects with chronic diseases. Although skin test responses in these subjects were blunted, in most residents cellular-mediated immunity remained intact.