Evaluation of Erythrocyte G6PD Activity Unit; It is Better Defined as a Function of RBC Count

Necat Yılmaz; Ayşe Binnur Erbağcı

doi:10.58600/eurjther.1999-10-1-2-1520-arch

Authors

Necat Yılmaz Department of Biochemistry and Clinical Biochemistry, Faculty of Medicine, University of Gaziantep, Turkey
Ayşe Binnur Erbağcı Department of Biochemistry and Clinical Biochemistry, Faculty of Medicine, University of Gaziantep, Turkey

DOI:

https://doi.org/10.58600/eurjther.1999-10-1-2-1520-arch

Keywords:

Erythrocyte G6PD, RBC, hemoglobin, MCV

Abstract

Glucose 6-phosphate dehydrogenase (G6PD) deficiency, one of the most common red celi abnormalities, is characterized by wide clinical, biochemical and molecular heterogeneity. in clinical laboratories erythrocyte ·G6PD activity is defined either as a function of hemoglobin (Hb) concentration or red blood celi (RBC) count and seldom hematocrit (Hct). These parameters are variable tor every individual and misinterpretation of the results cannot be avoided with reference interval establishment studies unless the best approach that define erythrocyte G6PD activity is selected. Hb concentration is frequently prone to the effects of genetic, physiological and environmental factors where G6PD activity should correlate with RBC count even when it is altered. in this study relations of the erythrocyte G6PD activity with RBC count, Hb concentration of the erythrocyte suspensions and RBC indices of 242 individuals were studied. Additionally, relations with platelet and white blood celi (WBC) counts were evaluated to determine possible interference. Erythrocyte G6PD activity was determined with kinetic spectrophotometric method according to the ICSH at 3o0 c. RBC, WBC, platelet counts, hemoglobin concentration of the erythrocyte suspensions and erythrocyte indices were determined with an automatic complete blood counter. Enzyme activity was correlated with RBC count (r: 0.53, p<0.001), there was no correlation with Hb (p>0.05). The negative correlation of the enzyme activity with MCV and MCH (r: -0.44 and r: -0.29, p<0.001 ), disappeared as a ratio of RBC count (p>0.05) and strengthened as a ratio of Hb concentration (r: -0.61 and r: -0.44, p<0.001 ). in this study a correlation of erythrocyte suspentions' platelet, leucocyte count and the enzyme activity as a ratio of Hb (r: 0.33 and r: 0.25, p<0.001) was observed. On the other hand enzyme activity as a ratio of RBC was only poorly correlated to WBC count (r: 0.15, p<0.01 ). Results of this study indicate that erythrocyte G6PD activity is related to RBC count and has several advantages over Hb in assessing G6PD status. it gives more reliable results in conditions that could affect erythrocyte morphology and Hb concentration.

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