Analytical evaluation of the ADAMS(™) A1c HA 8180 thalassemia mode high-pressure liquid chromatography analyser for the measurement of HbA2 and HbF.

BACKGROUND: ADAMS(™) A1cHA-8180T is a HPLC system; within 3.5 min, it quantifies HbF, HbA2 , and HbA0 and flags abnormal peaks. We evaluate its analytical performance for routine estimation of HbA2 and HbF, and critical tests were performed for identifying β-thalassemia carriers.

METHODS: Trueness imprecision, carry over, linearity, and effect of anemia were evaluated according to ICLH, ICLS, or manufacture's guidelines. Comparison (ADAMS(™) A1c HA-8160T) was performed by running 400 samples from healthy subjects, 30 alpha and 80 beta carriers (range: 1.9-5.7 %).

RESULTS: Trueness - HbA2 2.7 %, bias 0.81 %; HbA2 5.8 %, bias 0.38 %. HbA2 4.0% is not affected by Hb in the range 221-40 g/L. Carry over was negligible. Within run: normal control - CV 1.5 %, high control - CV 0.9 %.Within laboratory: normal control - total CV% 1.59%; high control - 0.92 %. Linearity - y = 1.034x - 0.17, R(2 ) = 0.998 (range: 2.8-4.8%).Method comparison - y = 0.93x + 0.22, R(2)  = 0.997. HbF imprecision CVs between 0.66 and 1.24% and trueness between 0 and 2.8%. Linearity - y = 1.088x - 0.27, R(2)  = 0.999 (0.1-5.7%).

CONCLUSIONS: ADAMS(™) A1c HA-8180T provides a rapid and reliable separation of HbA2 . The measurement is accurate and reproducible, which is needed because of the slight difference between normal and pathological values. The gap in HbA2 values between normal subjects and β-thalassemia carriers makes this an appropriate method for rapid screening for carriers.