TITLE:
Tenofovir Renal Toxicity: Evaluation of Cohorts and Clinical Studies—Part One
AUTHORS:
Adikwu Elias, Ogbuehi Ijeoma, Nkereuwem Jonathan Edikpo, Deo Oputiri, Oru-Bo Precious Geoffrey
KEYWORDS:
Tenofovir; Pharmacology; Renal; Toxicity; Cohorts
JOURNAL NAME:
Pharmacology & Pharmacy,
Vol.4 No.9,
December
9,
2013
ABSTRACT: Tenofovir is one of the most commonly
used antiretrovirals in adolescents and adults because of its potency and favorable pharmacokinetic and relative safety
toxicological profile. It has been combined successfully with antiretroviral
drugs from classes such as protease inhibitors, non-nucleoside reverse transcriptase
inhibitors and nucleoside reverse transcriptase inhibitors to achieve virologic
suppression in a high percentage of recipients. Despite its therapeutic success, quite a number of cohorts and
clinical studies have associated tenofovir with the development of renal
toxicity with few studies on the opposing end. This stimulated us to review
reported cohorts and clinical studies on tenofovir renal toxicity. In this
study it was observed that literature reported incidence of tenofovir renal toxicity falls within
the range of 0.7%-17%.
Available studies gave different appellations to tenofovir renaltoxicity, which include fanconis syndrome, proximal tubule
dysfunction, acute renal failure, chronic renal failure, chronic kidney disease
and nephrogenic diabetes insipidus. Markers of renal toxicity
(tubulopathy) which include glycosuria, hyperaminoaciduria, proteinuria, hyperphosphaturia,
hyperuricosuria, retinol-binding protein, beta2-microglobulinuria, decreased creatinine clearance and decreased glomerular filtration rate were also
reported. In some studies renal biopsy demonstrated cytoplasmic
vacuolization, apical localization of nuclei and reduction of the brush border
on proximal tubule epithelial cells. This study observed that tenofovir renal
toxicity could be reversible on discontinuation of tenofovir therapy despite
contrary views by some studies. Regardless of tenofovir reported renal
toxicity, it is well tolerated with a relative safety profile but it is advised
that renal profile of patients should be evaluated before and routinely during
tenofovir therapy.