HB UBE-2 variant hemoglobin case detected during HBA1C measurement
Öz
Hemoglobin A1c is used in the diagnosis and the management of Diabetes Mellitus. The accuracy of hemoglobin A1c measurements may be affected by various factors and the most common interferences are variant hemoglobins. During hemoglobin A1c measurement of a 56-year-old female patient with Type 2 Diabetes Mellitus, an abnormal peak was detected in the chromatogram by high performance liquid chromatography and an inconsistency was determined between the serum glucose and the hemoglobin A1c value. Patient’s hemoglobin A, hemoglobin A2, hemoglobin F and variant hemoglobin were detected as 73.3, 2, 0.3 and 24.4% respectively in the capillary electrophoresis. Hemoglobin value of patient was 13.5 g / dL, red blood cell 4.40x106 / µL, mean cell volume 89.8 fL, mean corpuscular hemoglobin 30.7 pg and the blood smear examination was evaluated as normal, however, heterozygote (αube-2α/αα) NM_000558.4 c.205A>G p.(Asn69Asp) variation was detected in hemoglobin A1 gene by whole exome sequencing and this variation is defined as hemoglobin Ube-2. It should be known that variant hemoglobin may affect to hemoglobin A1c measurements and especially when the results are incompatible with patient’s clinical status, this effect should be considered.
Anahtar Kelimeler
Hemoglobin A1c, Variant hemoglobin, Hemoglobin Ube-2, Interference
Kaynakça
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