Validation of the Accutrend ® lactate meter for hyperlactatemia screening during antiretroviral therapy in a resource-poor setting

Abstract

The use of highly active antiretroviral therapy (HAART) results in multiple side effects that may jeopardize the life of the patient being treated with antiretroviral drugs. In resource-poor settings it is difficult to definitively diagnose lactic acidosis by laboratory measurement of lactate. Point-of-care (POC) devices are helpful in the measurement of lactate levels and have been validated in the intensive care unit setting, but not in a busy outpatient clinic. The objective of this study was to assess the sensitivity and specificity of the Accutrend lactate meter in the diagnosis of hyperlactatemia/lactic acidosis in patients on nucleoside reverse transcriptase inhibitor (NRTI)-containing regimens (stavudine). This was a cross-sectional study of 120 patients on HAART (lamivudine, stavudine, efavirenz, or nevirapine) with symptoms of/or recovering from hyperlactatemia/lactic acidosis. Simultaneous testing of the same blood sample was undertaken on the Accutrend handheld lactate analyzer and a reference instrument (Beckman CX7 Synchron machine). A venous lactate level <2.2mmol/l was considered as normal. The mean lactate value obtained from the Accutrend meter was 2.89mmol/l and from the reference instrument was 2.78mmol/l. The standard deviation for Accutrend meter was 1.14mmol/l vs.1.42mmol/l for the Beckman instrument. The sensitivity obtained for the Accutrend meter was 95.9% (95% CI 87.7-98.9%) and the specificity 63.8% (95% CI 48.5-76.9%). The positive predictive value was 80.5% (95% CI 70.3-87.9%) and the negative predictive value was 90.9% (95% CI 74.5-97.6%). The Accutrend lactate meter is an appropriate device for screening patients on HAART with symptoms of hyperlactatemia/lactic acidosis. The use of this device decreases analytic and intervention time, preventing further morbidity and mortality in patients on an NRTI (stavudine)-based regimen.