Inmunosenescencia: pruebas cutáneas de hipersensibilidad retardada en adultos mayores chilenos autovalentes / Immunosenescence: delayed cutaneous hypersensitivity test in free living chilean elderly individuals

Background: Delayed cutaneous hypersensitivity tests are a globally accepted test to assess cellular immunity in vivo. The quality and quantity of the response to these type of tests, varies in different populations. Aim: To study delayed cutaneous hypersensitivity in a group of healthy Chilean elders. Material and methods: Forty two elders (32 male), aged 60 to 76 years old were studied. Multitest-CMI(r) was applied in the left forearm. This test allows the subcutaneous administration of seven antigens and a glycerin control. Results were compared with those of a group of young adults studied by the authors. Results: Among males there was a mean of 2.7 ñ 1.4 positive responses compared with women, that had 1.7 ñ 1 positive responses (p= 0.016). The sum of response diameters was 4.2 ñ 1.5 and 3.6 ñ 1.9 mm in men and women respectively (p = NS). Compared to young adults, elderly women had a lower response to tetanus and diphtheria toxoids and men had a lower response to diphtheria and Proteus mirabilis. Conclusions: Elderly people have a less intense response to delayed cutaneous hypersensitivity tests than young adults. This response must be assessed in each population to account for regional variability

Correlación entre multitest-CMI in vivo v/s determinación de subpoblaciones de linfocitos T in vitro / Correlation between in vivo multitest-CMI versus peripheral blood T-lymphocytes determination in vitro

Para la evaluación de la inmunidad mediada por células (CMI) existen técnicas de cuantificación y funcionales, por ejemplo el multitest-CMI (MT-CMI). La CMI es función del linfocito T CD4(+) asumiendo la intensidad de la respuesta proporcional al número de LT-CD4(+) circulantes. Se analizaron determinaciones simultáneas de MT-CMI, usando el aplicador cutáneo múltiple, con siete antígenos más un control negativo; y subpoblaciones linfocitarias por inmunofluorescencia indirecta. El teorema de Bayes y cálculo de correlación se usaron para la estadística. El "r" arrojado demostró que no había correlación entre ambas técnicas y el valor predictivo positivo (Vpp) fue de 36,14 por ciento par MT-CMI y para LT-CD4(+) de 73,17 por ciento. Para la evaluación diagnóstica inicial se debe incluir el recuento de subpoblaciones linfocitarias como el estudio cuantitativo y el test cutáneo como estudio funcional de la inmunidad celular

Hipersensibilidad retardada a antígenos de evocación: valores normales en adultos jóvenes chilenos / Delayed hypersensitivity to evocation antigens: standard values in chilean young adults

Delayed hypersensitivity skin test are widely accepted as in vivo measure of cellular immunity. Since genetic and environmental factors may affect these tests, each population must establish its own normal values. The aim of this work was to study delayed hypersensitivity in chilean normal young adults. We studied the response to 8 antigens using the Multitest CMI (Rhodia Merieux) in 50 students (22 females, 28 males), aged 18 to 25 years old. Skin tests were read at 24, 48 and 72 hours. At 48 h, 60 percent of women responded to 3 and 68 percent of men to 4 antigens. A mean response to 3.6 antigens was observed. Total score in men and women were 19.5ñ7.3 and 12.2ñ6.5 mm respectively (p<0.05). These figures are different from these published abroad and confirm the need for national standards