Pediatric Clinics of North America - CIPERJ

478 KWIATKOWSKI
and testing for organ dysfunction are used to monitor efficacy and make
dose adjustments. Patient interviews and examinations, serial measurements
of growth and pubertal development, appropriate laboratory studies (see
Table 2), and annual ophthalmologic examination and audiologic testing
are used to monitor for toxicity.
Summary
Effective chelation therapy can prevent or reverse organ toxicity related
to iron overload, yet cardiac complications and premature death continue
to occur, largely related to difficulties with compliance that may occur in patients
who receive parenteral therapy. The use of oral chelators may be able
to overcome these difficulties and improve patient outcomes. Two oral
agents, deferiprone and deferasirox, have been studied extensively and are
in clinical use worldwide, although in North America, deferasirox currently
is the only approved oral chelator. Newer oral agents are under study. The
chelator’s efficacy at cardiac and liver iron removal and side effect profile
should be considered in tailoring individual chelation regimens. Broader options
for chelation therapy, including possible combination therapy, should
improve clinical efficacy and enhance patient care.
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