Analysis of Changes in Adipose Tissue of Patients With Lipoatrophy HIV Infection Treated With Nucleoside Thymidine, After Switching to Monotherapy With Lopinavir / Ritonavir

Inclusion Criteria: * Patients infected with VIH-1, documented with a positive HIV-1 antibody test and/or positive PCR, confirmed for HIV-1 RNA. * Patients treated with a HAART that should contain AZT+3TC+ABC (Trizivir®) * Patients with an indetectable viral load, which will be defined \<40 copies/mL within the last six months. * Patients with a lipoatrophy clinical evidence (which will be defined as moderate or severe, according to the Lipodystrophy Severity Grading Scale). * Men or women aged ≥ 18. * For women of childbearing potential, negative urine pregnancy test during the Screening visit. * Patients that have signed and dated the Informed consent Form prior to any Study-specific procedure. Exclusion Criteria: * Patients with evidence of protease inhibitors failure, and/or documented evidence of protease gene resistance mutation. This evidence could be prior or during the inclusion period in the Study. * Patients who, for any reason could not be treated with LPV/r. * Cachexia, defined as an Body Mass Index \<17 Kg/m2. * Pregnant or breastfeeding women, or women of childbearing potential who do not use the appropriate contraceptive method, according to the Investigator judgment. * Clinically relevant disease or condition, according to the Investigator judgment, three months prior to the patient inclusion in the Study. * Patients taking the following concomitant medication that could affect the adipocyte function or morphology, such as: insulin, steroids, anabolic steroid, anti-inflammatory medication for more than three months.