Prevalence of Nephrotoxicity in HIV Patients Treated with Tenofovir Disoproxil Fumarate: A Single-center Observational Study

Abstract

Objectives Tenofovir disoproxil fumarate (TDF) has been reported to cause nephrotoxicity necessitating cessation in some patients. No information is available on the nephrotoxic effect of TDF in Omani or regional patients with HIV infection. We sought to determine the prevalence of the nephrotoxic effects of TDF in our cohort of Omani patients with HIV and investigate the nephrotoxic effects of other cofactors. Methods We conducted an observational cohort study on 83 Omani patients currently on TDF-containing antiretroviral therapy. Renal dysfunction was monitored by measuring the serum creatinine estimated glomerular function rate (eGFR), urinary protein creatinine ratio (uPCR), and fractional excretion of phosphate (FEPi). Fisher’s exact test was used to determine any additional nephrotoxic effects of cofactors. Results The median values for the duration of TDF use, patient age, and body mass index (BMI) at the time of the study were 178 weeks (range = 3–554), 42 years (range = 21–80), and 27 (range = 17.4–42.7), respectively. The median initial CD4 count and viral load were 205 × 10 6 /L (range = 3–1745) and 37 250 copies/mL (range = undetectable–9 523 428), respectively. FEPi was high in two (2.4%) patients, moderate in 26 (31.3%), and low in 55 (66.3%) patients. uPCR was high in 10 (12.0%) patients, moderate in 28 (33.7%), and low in 45 (54.2%) patients. No cofactors added to the nephrotoxicity except hypertension ( p = 0.045). Conclusions Better definitions for TDF-associated toxicity are needed. uPCR is not a very good indicator of TDF-associated tubular dysfunction. Omani patients with HIV on TDF have a 4% prevalence of renal toxicity, but a study with a larger number of patients is required to explore this observation further. Cofactors like duration of TDF use, age, BMI, gender, diabetes mellitus, and use of protease inhibitors did not have an impact on the severity of FEPi and uPCR.

A prospective cohort study of renal function and bone turnover in adults with hepatitis B virus (HBV)‐HIV co‐infection with high prevalence of tenofovir‐based antiretroviral therapy use

“…However, our finding that vitamin D supplementation was related to lower vitamin D insufficiency and deficiency prevalence supports its utility in this population. Finally, unlike most other studies [ 22 ], we did not see an impact of boosted versus unboosted TDF on bone health.…”

“…Quantitative HBV DNA and hepatitis B e‐antigen (HBeAg) (tested every 24 weeks) and quantitative HBsAg (tested every 48 weeks) were performed centrally at University of Washington, Seattle, WA, USA as previously described [ 22 , 24 ]. HBV DNA was categorized as <10 (undetectable), 10–<1000 (suppressed) and ≥1000 IU/ml (not suppressed).…”

“…The mechanism of renal impairment may be related to the effect of TDF on the proximal tubule and has been associated with markers of tubular dysfunction including increased risk of proteinuria, phosphaturia and glucosuria [ 15 , 21 ]. Risk factors for renal toxicity may also include older age, underweight, diabetes mellitus (DM), hypertension and first‐generation protease inhibitors (PI) use [ 10 , 22 ].…”

Prognostic model for nephrotoxicity among HIV-positive Zambian adults receiving tenofovir disoproxil fumarate-based antiretroviral therapy

“…The scientific basis for building a predictive model for TDF-associated nephrotoxicity suggest that the current standard biomarker for detecting nephrotoxicity or renal disorders (serum creatinine and eGFR) were not good enough because they seem to deflect late, often after the renal damage has taken place; therefore, predicting impending TDF-associated nephrotoxicity and injury might provide a prevention strategy [28,30,46]. With 22% of participants developing TDF-associated nephrotoxicity, the incidence concurred with a Japanese study [26], but was higher and not consistent with some African studies [47][48][49], probably because of the different criteria used to define nephrotoxicity and different censoring timings. The…”

Effect of anti-retroviral regimen on proximal tubular function in Zambian adolescents and young adults living with HIV: A cross sectional study

“…Therefore, PTD is associated with elevated urinary excretion of phosphate in the presence of hypophosphatemia 11 . FePO4 has been used to assess for PTD in people living with HIV (PLHIV) on tenofovir regimens 5,[15][16][17][18] .…”