Wasting in HIV infection and AIDS

AIDS wasting is not characterized by a single pathophysiological process bu t by a variety of processes that operate at different times. Acute wasting tends to be associated with secondary infections; chronic wasting is associ ated with gastrointestinal disease. Although resting energy expenditure is increased, total energy expenditure is reduced in individuals who are losin g weight and it is usually reduced intake that commonly drives wasting. How ever, reduced intake is not an adequate explanation for the metabolic abnor malities that are seen in HIV infection. In particular, protein metabolism and lipid metabolism are abnormal, possibly representing inappropriate util ization of substrates. The response to nutrition may be impaired, particula rly in terms of accrual of lean tissue but nutritional support may prolong survival, The impact of protease inhibitors on wasting in HIV infection is yet to be fully ascertained but despite antiviral therapy it seems that was ting is likely to remain a problem at least in some patients.