RT Journal Article
SR Electronic
T1 P2.195 A Case Series of Tenofovir Induced Nephrotoxicity
JF Sexually Transmitted Infections
JO Sex Transm Infect
FD BMJ Publishing Group Ltd
SP A147
OP A147
DO 10.1136/sextrans-2013-051184.0459
VO 89
IS Suppl 1
A1 S L Kay
A1 K Hall
A1 K Radcliffe
YR 2013
UL http://sti.bmj.com/content/89/Suppl_1/A147.2.abstract
AB Introduction Tenofovir (TDF) is a commonly used nucleotide reverse transcriptase inhibitor, effective in the management of HIV-positive individuals and chronic Hepatitis B infection. We report two cases that highlight the rare but significant nephrotoxic adverse effects of TDF on mitochondrial-rich proximal renal tubular cells, causing acute and chronic kidney impairment. We also show that removal of TDF results in partial improvement of the renal dysfunction. Case reports The first case describes a patient with long standing HIV who develops Fanconi syndrome, nephrogenic diabetes insipidus, acute tubular necrosis and tubulointerstitial nephritis, three years after TDF initiation. The second case reports a patient who developed acute severe kidney injury, requiring management with emergency haemodialysis, two weeks after TDF was initiated. In both cases renal biopsy showed extensive tubular injury and histology consistent with TDF induced renal injury. Both individuals had improved renal function following TDF cessation, but ongoing chronic kidney disease. Discussion Nephrotoxicity has been demonstrated in 17–22% of TDF-treated patients and occurs due to TDF accumulation in cell membrane transporters within proximal tubular cells, where it targets the mitochondria. TDF-related nephrotoxicty presents in a number of ways including proximal tubular dysfunction, acute and chronic kidney injury and a partial or complete Fanconi syndrome. Histological findings most commonly show proximal tubular injury. TDF specific histology is related to prominent eosinophillic intracytoplasmic inclusions, representing giant mitochondria. Conclusion TDF is a popular choice of antiretroviral therapy due to its efficacy, low side effect profile and use in monotherapy regimes. These cases highlight the potentially life-threatening complications of TDF-related nephrotoxicty. It also shows the importance of renal function monitoring and the withdrawal of TDF to prevent chronic renal impairment.