This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The Purpose of this study is to determine the influence of body composition on GFR predictions (creatinine clearance, MDRD, cystatin C) in HIV patients with wasting and/or lipoatrophy. Iothalamate clearance will be obtained as true measure of GFR and whole body DEXa will be used to quantify body composition. The result of this study will identify the most acurate method for estimation of renal fuction which is vital to accurate dosingof antretrovirals and early detection of mild renal disease in patients with HIV.