Abstract: PUB023
Interstitial Nephritis with Tenofovir-Containing Pre-exposure Prophylaxis (PrEP)
Session Information
Category: Acute Kidney Injury
- 102 AKI: Clinical, Outcomes, and Trials
Authors
- Bergmann, Matthias, Beth Israel Deaconess Medical Center, Boston, Massachusetts, United States
- Williams, Mark E., Joslin Diabetes Center, Boston, Massachusetts, United States
- Raines, Nathan H., Beth Israel Deaconess Medical Center, Boston, Massachusetts, United States
Introduction
Use of pre-exposure prophylaxis (PrEP) for people at high risk of HIV infection has increased worldwide. Emtricitabine/tenofovir disoproxil (TDF) has been most used but is known to rarely cause tubular dysfunction and tubular necrosis (TN) through drug accumulation and mitochondrial damage. Emtricitabine/tenofovir alafenamide (TAF) has been approved for PrEP as an alternative agent with less nephrotoxicity, attributed to better plasma stability and lower plasma levels of the active agent. We present the case of a 51-year-old man using TDF-based PrEP who developed acute kidney injury (AKI) from interstitial nephritis (IN).
Case Description
A 51-year-old man with type 1 diabetes mellitus on insulin injections, hypertension on amlodipine, and HIV-PrEP with emtricitabine/tenofovir underwent urgent renal biopsy for AKI. Creatinine was elevated to 3.9 from 1.6 mg/dL at a 3-months follow-up visit and increased further to 4.6 mg/dL within one week. Urine albumin to creatinine ratio (UACR) had increased from 233 to 826 mg/g. A1c was stable at 6.7%, chemistry was without any significant abnormalities, and renal ultrasound was unremarkable. Complement levels were normal and serum protein electrophoresis showed no monoclonal abnormalities. HBsAg, HCV-Ab, and HIV screen were negative. Urine sediment showed only few fine granular casts. Renal biopsy showed IN. He was initiated on 60 mg prednisone daily for two weeks followed by a slow taper. Tenofovir-containing PrEP was discontinued. Within two months, creatinine decreased to 2.24 from 4.67 mg/dL and UACR decreased to 172 from 826 mg/g.
Discussion
We report the case of a 51-year-old man using tenofovir-containing HIV-PrEP who presented with AKI and underwent renal biopsy showing IN. TDF has been described to cause TN while TAF is thought to be less nephrotoxic. Our patient was initially considered for conversion to TAF due to suspected tenofovir toxicity. However, renal biopsy showed IN. Creatinine and UACR decreased within two months of initiation of high-dose prednisone and discontinuation of all tenofovir-containing agents. This case emphasizes the importance of a renal biopsy for AKI with PrEP to avoid missed treatment opportunities. Our patient would likely have been continued on an alternative tenofovir-containing agent and would not have been treated with glucocorticoids without the histopathologic diagnosis of IN.