Composition corporelle au cours de l'infection à VIH : physiopathologie, méthodes de mesure et revue des résultats

Abstract

The immunological linkage between infection and nutritional status was well established even before the AIDS epidemic. AIDS-associated malnutrition alters cellular immunocompetence by decreasing phagocytic function, antibodies secretion, complement system, and number of lymphocytes. Vitamin and oligofactors deficiency increases the dysimmunity. Relations between nutritional status, infectious disease, and immunity system suggest that nutrition could act as a co-factor in the HIV progression. Correlation between survival and weight loss has been shown. Death occurs when loss of 50% of the lean body mass or of 34% of body weight is observed. Furthermore body composition studies have displayed a decrease of body cell mass out of proportion with the discharge in fat or weight. But what is not yet correctly identified is the impact of malnutrition on immunocompetence of a given subject. A significantly longer survival seems likely in patients whose body cell mass is over 30% of total weight, or whose albumin level goes beyond 30 g/L, this criterian being non-specific; parameters of nutritional status are independent of CD4 lymphocytosis, and would have a high predictive value of the survival time. So, early screening of body composition alterations must be used to identify the sligh test erosion of lean mass, as soon as seroconversion is known, even during treatments, using non-invasive, non-expensive, reproducible methods (and no longer weight loss only). This preventive attitude will increase metabolism knowledge about seropositivity status, in time for carrying out adjusted realimentation measures, for providing planned physical activity advice to develop muscular mass.