Lactic acidosis in an HIV-infected patient receiving highly active antiretroviral therapy

Background A 51-year-old man with HIV infection on highly active antiretroviral therapy presented with abdominal pain and exertional dyspnea. Physical examination revealed increased respiration and cachexia. Laboratory tests showed a lactic acid concentration elevated to 6.4 mM. Investigation Physical examination, blood chemistry, arterial blood gas, urine analysis, chest X-ray, and ultrasound of liver. Diagnosis Nucleoside reverse transcriptase inhibitor (NRTI)-induced lactic acidosis, hepatitis and chemical pancreatitis. Proximal renal tubular acidosis with Fanconi's syndrome, secondary to treatment with tenofovir. Management The patient was supported on intravenous and oral bicarbonate, riboflavin and phosphorus supplementation. Highly active antiretroviral therapy was discontinued. The patient's lactate level decreased about 2 weeks after discharge.