Growth failure and bony changes induced by deferoxamine

Area of Science:

• Pediatric Endocrinology
• Hematology
• Bone Biology

Background:

• Beta-thalassemia requires iron chelation therapy to manage transfusional iron overload.
• Deferoxamine mesylate is a primary treatment for iron overload in thalassemia patients.
• Growth impairment is a known complication in children with beta-thalassemia.

Purpose of the Study:

• To investigate the impact of nightly subcutaneous deferoxamine therapy on linear growth and growth plate morphology in children with homozygous beta-thalassemia.
• To determine if deferoxamine therapy is a causative factor in growth failure and associated bony changes.
• To identify potential risk factors, such as age at initiation of therapy, associated with deferoxamine-induced growth impairment.

Main Methods:

• Retrospective review of children with homozygous beta-thalassemia receiving nightly subcutaneous deferoxamine.
• Analysis of monthly height percentiles before and for 36 months after therapy initiation.
• Assessment of growth plate morphology, specifically in distal ulnar, radial, and tibial metaphyses.
• Comparison of growth patterns between patients initiating deferoxamine before age 2 versus after age 5.

Main Results:

• 11 of 37 patients showed marked growth plate abnormalities and a significant decline in height percentile.
• These 11 patients received higher deferoxamine doses and had lower mean serum ferritin levels.
• Patients initiating deferoxamine before age 2 demonstrated a significant decline in height percentile by year three, implicating the therapy.

Conclusions:

• Deferoxamine therapy is directly related to both the decline in height percentile and observed bony changes in well-chelated patients.
• Early initiation of deferoxamine therapy (before age 2) is associated with a greater risk of growth failure.
• Growth plate abnormalities in the metaphyses are a key finding in patients experiencing deferoxamine-induced growth impairment.