Distal renal tubular acidosis without renal impairment after use of tenofovir: a case report

BACKGROUND: Tenofovir, one of antiretroviral medication to treat human immunodeficiency virus (HIV) infection, is known to cause proximal renal tubular acidosis such as Fanconi syndrome, but cases of distal renal tubular acidosis had never been reported. CASE PRESENTATION: A 20-year-old man with HIV infection developed nausea and vomiting without diarrhea after starting antiretroviral therapy. Arterial blood gas revealed non-anion-gap metabolic acidosis and urine test showed positive urine anion gap. Tenofovir, one of antiretroviral medicine the patient received, was considered to be the cause of this acidosis and all antiretroviral drugs were discontinued. Symptoms disappeared promptly without recurrence of symptoms after resuming antiretroviral medications without tenofovir. CONCLUSION: Distal renal tubular acidosis caused by tenofovir, without renal impairment is very rare. Since causes of nausea and vomiting among HIV/AIDS patients are very diverse, awareness of this phenomenon is useful in diagnosing and managing the problem.