Evin KOCATÜRK, Zeynep KUSKU KİRAZ, Şükrü DEMİR, Oğuz ÇİLİNGİR, İ. Özkan ALATAŞ, Hava ÜSKÜDAR TEKE

HBA1C ölçümü sırasında saptanan HB UBE-2 varyant hemoglobin olgusu

Hemoglobin A1c, Diabetes Mellitus'un tanısında ve hasta yönetiminde kullanılır. Hemoglobin A1c ölçümlerinin doğruluğu çeşitli faktörlerden etkilenebilir ve en çok karşılaşılan interferans varyant hemoglobinlerdir. 56 yaşında Tip 2 Diabetes Mellitus’u olan kadın hastanın hemoglobin A1c ölçümü sırasında, yüksek performanslı likit kromatografi ile kromatogramda anormal bir pik tespit edildi ve serum glukozu ile hemoglobin A1c değeri arasında tutarsızlık tespit edildi. Kapiller elektroforezde hastanın hemoglobin A, hemoglobin A2, hemoglobin F ve varyant hemoglobini sırasıyla% 73.3, 2, 0.3 ve 24.4 olarak tespit edildi. Hastanın hemoglobin değeri 13.5 g / dL, eritrosit sayısı 4.40x106 / µL, ortalama eritrosit hacmi 89.8 fL, ortalama korpüsküler hemoglobin 30.7 pg idi ve periferik yayma incelemesi normal olarak değerlendirildi, ancak heterozigot (ααube-2α / αα) NM_000558 .4 c.205A> G p. (Asn69Asp) varyasyonu hemoglobin A1 geninde tam ekzon sekanslama yöntemi ile tespit edilmiş ve bu varyasyon hemoglobin Ube-2 olarak tanımlanmıştır. Varyant hemoglobinin hemoglobin A1c ölçümlerini etkileyebileceği bilinmeli ve özellikle sonuçlar hastanın klinik durumu ile uyumsuz olduğunda bu etki dikkate alınmalıdır.

HB UBE-2 variant hemoglobin case detected during HBA1C measurement

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.

Keywords:

Hemoglobin A1c, Variant hemoglobin, Hemoglobin Ube-2, Interference,

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