TY - JOUR T1 - Field evaluation of a prototype paper-based point-of-care fingerstick transaminase test. JF - PLoS One Y1 - 2013 A1 - Pollock, Nira R A1 - McGray, Sarah A1 - Colby, Donn J A1 - Noubary, Farzad A1 - Nguyen, Huyen A1 - Nguyen, The Anh A1 - Khormaee, Sariah A1 - Jain, Sidhartha A1 - Hawkins, Kenneth A1 - Kumar, Shailendra A1 - Rolland, Jason P A1 - Beattie, Patrick D A1 - Chau, Nguyen V A1 - Quang, Vo M A1 - Barfield, Cori A1 - Tietje, Kathy A1 - Steele, Matt A1 - Weigl, Bernhard H KW - Alanine Transaminase KW - Blood Chemical Analysis KW - Developing Countries KW - Drug Monitoring KW - Drug-Induced Liver Injury KW - Humans KW - Liver Function Tests KW - Microfluidics KW - Observer Variation KW - Paper KW - Point-of-Care Systems KW - Vietnam AB -

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.

VL - 8 IS - 9 U1 - http://www.ncbi.nlm.nih.gov/pubmed/24098705?dopt=Abstract ER -