Exposure to TDF is associated with an increased risk over time of kidney tubular abnormalities in the absence of significant impaired glomerular function. Although long-term consequences of this tubulopathy are unknown, close monitoring of accelerated bone mineral loss and renal insufficiency are warranted. Periodic screening of tubular function parameters should be recommended to patients receiving TDF.

Approximately 17% of HIV-infected patients treated with tenofovir had KTD. Homozygosity for the C allele at position -24 of the ABCC2 gene was strongly associated with KTD in this population. This polymorphism may help to identify patients at greater risk for developing tenofovir-associated tubulopathy, and close monitoring of renal function is warranted for these patients.

We examined 516G>T polymorphisms at the gene encoding the cytochrome P450 in 100 human immunodeficiency virus-positive subjects who were receiving efavirenz (EFV). Elevated plasma EFV concentrations were found in 40% of subjects with the polymorphic homozygous genotype and 19% of subjects with the heterozygous genotype. Conversely, 20% of subjects with the wild-type genotype had subtherapeutic concentrations of EFV. CYP2B6-516 genotyping may help to identify subjects who have plasma EFV concentrations that are outside of the therapeutic range.

Polymorphisms at MDR1-3435 significantly influence ATV plasma concentrations, as does being Caucasian patients with CT/TT genotypes, having lower ATV levels, even using ritonavir boosting. On the other hand, although ATV plasma concentrations directly correlate with bilirubin levels, the risk of severe hyperbilirubinemia is further increased in the presence of the UGT1A1-TA7 allele.

TFV is a substrate for ABCC10, and genetic variability within the ABCC10 gene may influence TFV renal tubular transport and contribute to the development of KTD. These results need to be replicated in other cohorts.