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

Background: 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 (R) lactate meter in the diagnosis of hyperlactatemia/lactic acidosis in patients on nucleoside reverse transcriptase inhibitor (NRTI)-containing regimens (stavudine). Design and methods: 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 (R) handheld lactate analyzer and a reference instrument (Beckman CX7 Synchron (R) machine). A venous lactate level <2.2 mmol/l was considered as normal. Results: The mean lactate value obtained from the Accutrend (R) meter was 2.89 mmol/l and from the reference instrument was 2.78 mmol/l. The standard deviation for Accutrend (R) meter was 1.14 mmol/l vs. 1.42 mmol/l. for the Beckman instrument. The sensitivity obtained for the Accutrend (R) 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%). Conclusions: The Accutrend (R) 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. (C) 2008 International Society for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.