Haematological parameters and HbA2 levels in beta-thalassaemia trait with coincident iron deficiency.

Iron status was estimated in 463 heterozygous beta-thalassaemics to delineate the effect of iron deficiency (ID) on the haematological parameters and expression of HbA2 in these patients. One hundred and twenty six (27.2%) traits had coincident ID. These iron deficient traits had a significantly (p < 0.0002), higher prevalence of anaemia (90.5%) as compared to iron replete traits (71.5%). Mean haemoglobin concentration was significantly lower (p < 0.0001) in beta-thalassaemics with ID (10.7 +/- 1.5) g/al as compared to those without ID (11.6 +/- 1.6 g/dl). Mean MCV and MCH were significantly lowered (p < 0.0001) in patients of beta-thalassaemia trait (BTT) with ID than in these without ID. Mean HbA2 was not significantly different in the two groups of traits and was elevated (> or = 3.5%) in all except one patient. However, mean HbA2/cell was significantly (p < 0.05) lower in traits with ID. The effect of ID in BTT was apparent with significant lowering of haemoglobin concentration and increased prevalence of anaemia. Iron therapy is warranted in iron deficient traits and would help in significantly raising their haemoglobin concentration. Elevation in HbA2 values was striking and could be used with reliability for diagnosis of BTT even in the presence of ID.