Point-of-Care Acute Kidney Injury Biomarker Testing for En Route Combat Casualty Care
Technical Report,20 Mar 2017,19 Jan 2020
University of Cincinnati Cincinnati United States
Pagination or Media Count:
Acute kidney injury AKI has been reported in up to 34.3 percent of casualties from recent conflicts. Over 80 percent of AKI occurred within the first 48 hours with a crude mortality of about 21.7 percent. Inadequate field andor en route care, as well as delayed recognition of AKI, contributes to excess mortality and morbidity. Point-of-care POC testing of AKI biomarkers enables early recognition of at-risk personnel for evacuation and direction to appropriate care facilities. The goal of our study was to develop and validate a carbon nanotube CNT-based POC immunoassay analyzer for detecting the AKI biomarkers from blood specimens. METHODS Neutrophil gelatinase associated lipocalin NGAL was selected as the initial AKI biomarker. A CNT-based immunoassay sandwich assay targeting NGAL was developed for an existing prototype analyzer developed by our team. Thirty residual whole blood specimens less than 1 mL collected at the time of admission from severely burned patients greater than 20 percent total body surface area were tested and compared to a laboratory reference method. Accuracy, imprecision, and analytical measurement range were determined. Chart review determined patient AKI status using the Kidney Disease Improving Global Outcomes criteria. RESULTS The POC NGAL assay did not significantly differ from the laboratory method mean bias standard deviation 4.5 10.7, P 0.082. Analytical measurement range was 1 to 1000 ngmL R2 0.98, y -0.20x 2.1. Imprecision was found to be 10 coefficient of variation at the literature cited decision point of 100 ngmL for determining AKI risk. NGAL values in AKI patients n 14 were significantly higher versus non-AKI patients n 16 125.6 10.1 vs. 73.7 15.2 ngmL, P less than 0.001. CONCLUSION Neutrophil gelatinase associated lipocalin shows promise as a POC AKI biomarker that could be employed for en route care.