SAT-194 Correlation of Capillary and Venous Plasma Measurements of Anti-Müllerian Hormone

Abstract

Anti-Müllerian Hormone (AMH) is a member of the transforming growth factor β superfamily which regulates gonadal development and differentiation. AMH is a biomarker for ovarian age and reserve used to assess fertility and predict ovulation induction outcome. It is also a marker for diagnosis and treatment of polycystic ovarian syndrome (PCOS), menopausal transition, and gonadal function. As diagnostic testing begins to expand into self-collection and point-of-care capabilities, there is a need to minimize sample volume requirements and include additional sample types. The TAP device, manufactured by Seventh Sense Biosystems (Medford, MA), is a small, easy to use, single push device that collects approximately 100 µL whole blood from the upper arm. As the blood travels through the channels of the device it is mixed with lithium heparin anticoagulant. The device collects capillary blood and is FDA approved for use in hemoglobin A1c measurements. In this study, AMH levels in venous and capillary plasma were compared. AMH was measured by an electrochemiluminescent immunoassay requiring only 40 µL plasma. The performance characteristics of the assay including accuracy, precision, linearity, and limits of quantitation were assessed. The stability of samples stored in the TAP device was also evaluated. Twenty-one female volunteers ages 24 to 67 donated paired venous and capillary blood samples. Venous plasma from donors with undetectable AMH levels was used as a matrix for spike and recovery studies to verify acceptable accuracy and precision across the analytical measurement range (AMR) and establish the lower (LLOQ) and upper (ULOQ) limits of quantitation. The ULOQ and LLOQ were 15 and 0.15 ng/mL, respectively. Accuracy was within 20% and precision within 15% across the AMR. Linearity was evaluated by serially diluting samples with high levels of AMH in AMH-negative pooled plasma. The maximum acceptable dilution was 8-fold. Correlation of venous and capillary results was excellent. A linear least square model resulted in a coefficient of determination (R2) of 0.998. Four capillary blood samples were collected from each of three donors for stability analysis. One was processed immediately and used as the baseline. The remaining three samples were stored at 2-8°C in the TAP device for 3, 5 and 7 days before processing. Plasma collected after 5 and 7-day storage in the TAP device was moderately hemolyzed and smaller volumes were retrieved. The hemolysis did not impact AMH measurement. AMH was stable at all time points tested with mean recovery of 104% compared to baseline values. This study shows that very small volumes of venous and capillary plasma can be used to accurately measure AMH levels. The ability to measure AMH in capillary blood via the TAP device allows for quick and reproducible blood collection, potentially outside the healthcare setting, improving access to diagnostic information.