Hemoglobin Fukuoka caused unexpected hemoglobin A(1c )results: A case report

BACKGROUND: Glycated hemoglobin (Hb) (HbA(1c)) is an indicator that is used to diagnose and monitor the treatment of diabetes. Many factors can affect the detection of HbA(1c). One of the most important of these factors is the Hb variant. Here, we report a rare Hb variant and evaluate its effect on HbA(1c). CASE SUMMARY: A 35-year-old man was suspected of harboring an Hb variant following the measurement of HbA(1c )with the Variant II Turbo 2.0 Hb detection system during a routine examination. Subsequently, we used the Arkray HA-8160 and ARCHITECT c4000 system to reanalyze HbA(1c). Finally, the Hb variant was detected with a Capillary2FP analyzer that operates on the principle of capillary electrophoresis. We also used gene sequencing to investigate the mutation site. The value of HbA(1c )detected with the Variant II Turbo 2.0 system was 52.7%. However, the Arkray HA-8160 system did not display a result while the ARCHITECT c16000 system showed a result of 5.4%. The Capillary2FP analyzer did not reveal any abnormal Hb zones. However, gene sequencing identified the presence of a mutation in the Hb β2 chain [CD2(CAC>TAC), His>Tyr, HBB: c.7C>T]; the genotype was Hb Fukuoka. CONCLUSION: Hb variants could cause abnormal HbA(1c) results. For patients with Hb variants, different methods should be used to detect HbA(1c).