Increase in Haemoglobin A2 Window among Healthy Children in Najran Area, Saudi Arabia

Abstract

INTRODUCTION: A minor increase in hemoglobin (Hb) A2 is common in B thalassemia trait in which Hb A2 usually exceeds 3.5%. Other inherited and acquired disorders result in minor increases that do not often exceed 8%. The remarkable increase (>20%) in Hb A2 may refer to other structural variants that also migrate in the Hb A2 window. The aim of this study was to assess the increased Hb A2 levels and their incidence among schoolchildren in Najran city. AIMS: The aim of this study was to assess the increased Hb A2 levels and their incidence among schoolchildren in Najran city. SUBJECTS AND METHODS: This study was conducted on 665 male students of Najran primary schools. All students were subjected to a full history taking and laboratory investigations including a complete blood count, peripheral blood smear examination, measurement of serum iron and ferritin levels, reticulocyte count, and alkaline Hb gel electrophoresis. RESULTS: Four (0.60%) students had highly significant (P = 0.000) increased Hb A2 levels above 20%. Three of them descend to the same tribe. Two cases had mild anemia and the other two cases had normal Hb levels. All cases showed microcytosis and hypochromia with normal serum iron and ferritin levels. CONCLUSION: Alkaline Hb electrophoresis showed highly significant increased Hb A2 levels among school children with microcytosis and hypochromia. Further investigations are required to ensure whether this is an increase of Hb A2 or from other Hb variants that take the same window of Hb A2.