Case 5: Antiretroviral Medications and Lactic Acidemia

Question | Discussion | References | CME Credit

Updated January 26, 2011

Authors:

A 29-year-old HIV-infected patient comes to the clinic for evaluation of 3 week history of fatigue, nausea, vomiting, and myalgias. In addition, she has lost 8 pounds in 6 weeks. She started taking a salvage antiretroviral therapy regimen 9 months ago that consists of stavudine (Zerit) plus didanosine (Videx EC) plus lopinavir-ritonavir (Kaletra). At the time she started this regimen, her CD4 count was 235 cells/mm³; it has now increased to 310 cells/mm³ and her HIV RNA has decreased to less than 50 copies/ml. She is taking no other medications and she does not use any illicit drugs. Initial laboratory studies show a white blood cell count of 6,230/mm³, hematocrit 38%, sodium 136 mEq/L, potassium 3.9 mEq/L, chloride 106 mEq/L, carbon dioxide 23 mEq/L, anion gap 11, aspartate aminotransferase (AST) 66 U/L, and alanine aminotransferase (ALT) 110 U/L.

Which one of the following statements is TRUE regarding the patient’s clinical presentation?

	The patient’s symptoms are consistent with lactic acidemia, but the normal serum bicarbonate level and normal anion gap effectively rules out lactic acidemia as a diagnosis.
	The patient’s symptoms are consistent with lactic acidemia and a serum lactate level should be obtained to establish the diagnosis of lactic acidemia. The likely drugs responsible are stavudine and didanosine.
	The patient’s symptoms are consistent with lactic acidemia. If the diagnosis of lactic acidemia is established and it is severe, the most important measure is to immediately prescribe riboflavin.
	The patient’s symptoms are not consistent with lactic acidemia and further laboratory evaluation is not required. Didanosine-induced adrenal insufficiency is a much more likely diagnosis.