Identifying patients at risk of NAFLD(Nonalcoholic fatty liver disease), especially severe disease with NASH(nonalcoholic steatohepatitis) and fibrosis, is critical. Prevalence of NAFLD in PLWH(People Living With HIV) evaluated by different imaging techniques including US (ultrasonography), elastography, CT(computed tomography ), and magnetic resonance varies from 13% to 58.6% in all published studies. In previous studies, the effect of ART(Anti-Retroviral Therapy) on NAFLD was limited. A cross-sectional analysis found that INSTI（Integrase strand transfer inhibitor） was associated with a higher prevalence of steatosis in AIDS (acquired immunodeficiency syndrome) patients. However, it is not clear whether there is a difference in the degree of nonalcoholic steatosis between AIDS patients receiving NNRTI(non-nucleoside reverse transcriptase inhibitors). Therefore, the investigators plan to conduct a prospective study to assess whether there is any difference in the degree of nonalcoholic steatosis and fibrosis between Chinese HIV(human immunodeficiency virus)/AIDS patients after initial treatment with NNRTI or INSTI, or switching from NNRTI to INSTI.