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Summary Peripheral blood lymphocyte sets and serum immunoglobulins were examined in 15 patients with thalassaemia intermedia, aged between 5 and 30 years. They were divided in three clinical groups: Group I, non-splenectomized, with serum iron (SI) lower than 200 μg/dl; Group II, splenectomized with serum iron lower than 200 μg/dl; and Group III, splenectomized with serum iron levels greater than 200 μg/dl. High absolute lymphocyte counts were observed in the majority of patients, whether splenectomized or not. Following splenectomy, marked increases were observed in absolute number of lymphocytes and percentages of circulating surface immunoglobulin (SIg) bearing B lymphocytes, mouse rosette forming cells (MRFC) and ‘null’ cells. The increases in circulating B lymphocytes following splenectomy were due exclusively to cells bearing SIgM and/or SIgD. No changes were observed in numbers and proportions of circulating SIgA or SIgG bearing cells. Serum IgA levels were high in the majority of patients studied whether splenectomized or not. Following splenectomy increases in serum IgA and serum IgG were observed which seemed to relate to increasing SI levels. No significant changes occurred in serum IgM levels. Absolute numbers of circulating T lymphocytes were unaffected by splenectomy or SI levels. Changes were observed, however, in distribution of T lymphocyte subsets with decreases in number of Tμ cells and concomitant increases in numbers of non-Tμ, non-Tγ cells. Tγ cells were the least affected by splenectomy and increasing SI. The results are compatible with the proposition that iron participates in the regulation of lymphoid cell migration and in the modulation of expression of cell surface markers. The findings also illustrate the role of the spleen in the control of lymphocyte migration and immunoglobulin production.

We have found bioassayable somatomedin activity to be subnormal in 20 of 32 children and adults with beta-thalassemia. The levels were comparable to values reported in growth hormone-deficient subjects. Since patients with thalassemia are not growth hormone deficient, the data suggest the possibility of defective hepatic biosynthesis of somatomedin. Increased iron stores in these patients, who have secondary hemosiderosis of many organs, including the liver, may depress somatomedin activity. Therapy for one year with daily subcutaneous infusions of the iron-chelating agent deferoxamine had no effect on mean bioassayable serum somatomedin activity.

This is the first case report of cataracts in patients with thalassemia major. Desferrioxamine, an iron-chelating agent is being used with increasing frequency in the treatment of transfusion-induced iron overload. There has been some concern in the literature about possible cataract formation with use of this drug. It is therefore important to document any lens opacities seen prior to administration of desferrioxamine, or record the appearance of lens opacities after its use. The possible eitology of these lens opacities is discussed.