@article {203, title = {Field evaluation of a prototype paper-based point-of-care fingerstick transaminase test.}, journal = {PLoS One}, volume = {8}, year = {2013}, month = {2013}, pages = {e75616}, abstract = {

Monitoring for drug-induced liver injury (DILI) via serial transaminase measurements in patients on potentially hepatotoxic medications (e.g., for HIV and tuberculosis) is routine in resource-rich nations, but often unavailable in resource-limited settings. Towards enabling universal access to affordable point-of-care (POC) screening for DILI, we have performed the first field evaluation of a paper-based, microfluidic fingerstick test for rapid, semi-quantitative, visual measurement of blood alanine aminotransferase (ALT). Our objectives were to assess operational feasibility, inter-operator variability, lot variability, device failure rate, and accuracy, to inform device modification for further field testing. The paper-based ALT test was performed at POC on fingerstick samples from 600 outpatients receiving HIV treatment in Vietnam. Results, read independently by two clinic nurses, were compared with gold-standard automated (Roche Cobas) results from venipuncture samples obtained in parallel. Two device lots were used sequentially. We demonstrated high inter-operator agreement, with 96.3\% (95\% C.I., 94.3-97.7\%) agreement in placing visual results into clinically-defined "bins" (<3x, 3-5x, and >5x upper limit of normal), >90\% agreement in validity determination, and intraclass correlation coefficient of 0.89 (95\% C.I., 0.87-0.91). Lot variability was observed in \% invalids due to hemolysis (21.1\% for Lot 1, 1.6\% for Lot 2) and correlated with lots of incorporated plasma separation membranes. Invalid rates <1\% were observed for all other device controls. Overall bin placement accuracy for the two readers was 84\% (84.3\%/83.6\%). Our findings of extremely high inter-operator agreement for visual reading-obtained in a target clinical environment, as performed by local practitioners-indicate that the device operation and reading process is feasible and reproducible. Bin placement accuracy and lot-to-lot variability data identified specific targets for device optimization and material quality control. This is the first field study performed with a patterned paper-based microfluidic device and opens the door to development of similar assays for other important analytes.

}, keywords = {Alanine Transaminase, Blood Chemical Analysis, Developing Countries, Drug Monitoring, Drug-Induced Liver Injury, Humans, Liver Function Tests, Microfluidics, Observer Variation, Paper, Point-of-Care Systems, Vietnam}, issn = {1932-6203}, doi = {10.1371/journal.pone.0075616}, author = {Pollock, Nira R and McGray, Sarah and Colby, Donn J and Noubary, Farzad and Nguyen, Huyen and Nguyen, The Anh and Khormaee, Sariah and Jain, Sidhartha and Hawkins, Kenneth and Kumar, Shailendra and Rolland, Jason P and Beattie, Patrick D and Chau, Nguyen V and Quang, Vo M and Barfield, Cori and Tietje, Kathy and Steele, Matt and Weigl, Bernhard H} }