The main risk factors for TDF nephrotoxicity include pre-existing renal impairment, older age, low body weight, advanced HIV disease (low CD4 count or AIDS), comorbidities (especially diabetes, hypertension and hepatitis C co-infection), concomitant use of nephrotoxic drugs and protease inhibitors.14,23,31 Countries in sub-Saharan Africa can expect to experience a large proportion of patients in whom the above-mentioned risk factors are present at ART initiation. This evidence concerns the gene CD4 and AIDS.