RESUMO
The authors tested the efficacy and safety of intermittent high doses of iv deferrioxamine (DFX) on a twice-weekly basis through an externalized venous catheter on 14 thalassemic children who were heavily iron-loaded and poorly or noncomplaint to subcutaneous DFX. The main reasons for their noncompliance were resistance of the child because of severe local reactions or more than one family member affected, with very high burden on the mother to look after all the affected children. There were 9 males and 5 females and their age range was 7-13 years (mean 10.93 +/- 1.9 years). All patients were given a 48-h continuous iv infusion of DFX 200-240 mg/kg/day (approximately 10 mg/kg/h) every 2 weeks, combined with subcutaneous 10-h infusion of DFX 3 days/week. One month after the start of the intermittent high-dose DFX program, the 24 h urinary iron excretion was 29.1-1.50 mg/kg/24 h (mean 69.7 +/- 32.5 mg/kg/24 h). These values dropped significantly to 29-53 mg/kg/24 h (mean 39.8 +/- 7.9 mg/kg/24 h) 1 year after the study (p <.004) and remained almost the same over the second year (mean 39.07 +/- 6.58 mg/kg/24 h). Serum ferritin levels markedly elevated before the start of high-dose chelation fell steadily during iv high-dose DFX therapy. Mean values were 6215.5 +/- 578.3, 3971.5 +/- 321.6, 2507.2 +/- 131.2, and 1866.5 +/- 110 ng/mL at 0, 6, 12, and 24 months, respectively. No serious side effects were reported. Intermittent high-dose DFX therapy combined with 3 days of subcutaneous DFX is safe and effective in reducing iron stores and improving the compliance of these heavily iron-loaded thalassemic children.
