Serum bleomycin-detectable iron in patients with thalassemia major with normal range of serum iron.

"Free" iron, a potentially radical-generating low mass iron, and not found in normal human blood, was increased in the serum of blood-transfused thalassemia major patients seen in the Yangon General Hospital, Yangon, Myanmar (Burma). The low mass iron was detected by the bleomycin assay. Fifty-one blood samples were analyzed (from 28 males and 23 females). High "free" iron was detected in 47 sera samples from thalassemia patients. Serum ferritin, which reflects the body store iron, was higher than the normal range (10-200 ng/ml) in 49 patients. On the other hand, serum iron of 39 sera samples fell within the normal range (50-150 micrograms/dl). Four were less than 50 micrograms/dl and eight were more than 150 micrograms/dl. Almost all the patients' sera of normal or higher serum iron level contained "free" iron. Thus, almost all the sera from thalassemic patients from Myanmar contain bleomycin-detectable iron, even when serum iron is within the normal range. In developing countries where undernutrition is prevalent (serum albumin in these patients was 3.6 +/- 0.4 g/dl, P < 0.0001 vs. control value of 4.0 - 4.8 g/dl), normal serum iron does not preclude the presence of free iron in the serum.