Abstract
Objective The interference of the hemoglobin variant (Hb J-Bangkok) was evaluated on 4 different
glycated hemoglobin assays and compared with a reference immuno assay.
Methods An overall test of coincidence of 2 least-squares linear regression lines was performed
to determine whether the presence of Hb J-Bangkok caused a statistically significant
difference in HbA1c results compared with a reference immuno assay. Statistical analysis
was performed on the difference of the estimated average glucose calculated from HbA1c
values and fasting plasma glucose in the Hb J-Bangkok variant group using the different
detection systems. Deming regression analysis was used to determinate whether Hb J-Bangkok
had a significant interference on HbA1c results using an HbA1c±10% relative bias at
6% and 9% HbA1c as evaluation limits.
Results Turbidimetric inhibition immunoassay method, and enzymatic methods were not affected
by Hb J-Bangkok. However, Hb J-Bangkok showed statistically significant interference
to the two ion-exchange high-performance liquid chromatography methods.
Conclusion When performing HbA1c tests, clinical laboratory personnel should identify the Hb
variant and select the appropriate methods or use alternative indicators.
Key words
hemoglobin variant - Hb J-Bangkok - glycated hemoglobin - HbA1c - interference
