Tenofovir toxicity commonly affects which organ?

• A. Liver
• B. Heart
• C. Lungs
• D. Kidney

Answer: (D)

Tenofovir is eliminated through the kidneys, so its toxicity most often affects renal function. It can cause proximal tubule dysfunction, sometimes leading to Fanconi-like syndrome, with signs such as rising creatinine and reduced eGFR, phosphate wasting, glycosuria with normal blood glucose, aminoaciduria, and sometimes metabolic acidosis from bicarbonate loss. Because of this, monitoring kidney function and electrolytes is essential during therapy, dose adjustments are needed for reduced GFR, and you should avoid concurrent nephrotoxic drugs (like NSAIDs or certain aminoglycosides). While Tenofovir can contribute to bone mineral density loss due to phosphate wasting, the organ most commonly impacted is the kidney. Hepatic, cardiac, or pulmonary toxicity is not the typical pattern for this medication.