Renal dysfunction is an increasingly recognized non-AIDS-defining comorbidity among HIV-infected persons. The role of HIV-related factors in renal dysfunction remains unclear. We performed a cross-sectional study at two military clinics with open access to care to determine the impact of HIV factors, including antiretroviral therapy, on renal function. Renal dysfunction was defined as a glomerular filtration rate (GFR) < 60 mL/min/1.73 m(2). We evaluated 717 HIV patients with a median age of 41 years; 92% were male, 49% Caucasian, and 38% African American; median CD4 count was 515 cells/mm(3) and 73% were receiving highly active antiretroviral therapy (HAART). Twenty-two patients (3%) had renal dysfunction. Factors associated with renal dysfunction in the multivariate logistic analyses included older age (odds ratio [OR] 2.0 per 10 year increase, p = 0.006), lower CD4 nadir (OR 0.6 per 100 cell change, p = 0.02), and duration of tenofovir use (OR 1.5 per year use, p = 0.01). Among persons initiating tenofovir (n = 241), 50% experienced a reduction in GFR (median -10.5 mL/min/1.73 m(2), 95% CI, -8.9 to -13.3) within 2 years. Among tenofovir users, factors associated with a reduction in GFR included female gender (p < 0.001), African American ethnicity (p = 0.003), and lower CD4 nadir (p = 0.002). In summary, renal dysfunction was relatively uncommon among our HIV-infected patients, perhaps due to their young age, lack of comorbidities, or as a result of our definition that did not include proteinuria. Renal dysfunction was associated with duration of tenofovir use. Factors associated with renal loss among tenofovir users included female gender, African American ethnicity, and CD4 nadir <200 cells/mm(3). Consideration for more frequent monitoring of kidney function among these select HIV patients may be warranted.