“Secondary lron overload: lmplications of Non-lnvasive Measurement” ：抄録

“Secondary lron overload: lmplications of Non-lnvasive Measurement” ：抄録

Performer: John K. Olynyk,
School of Medicine & Pharmacology, University of Western Australia,
Fremantle Hospital Campus, Department of Gastroenterology, Fremantle Hospital,
Western Australia

Recent advances in the understanding of the regulation of iron transport have substantially improved our knowledge of the pathogenesis of iron overload.

In normal circumstances, iron absorption and losses are in balance.

Iron is stored in the marrow and liver and levels of toxic non-transferrin bound iron（NTBI） or labile plasma iron（LPI） are low.

When iron overload occurs as a result of increased absorption or exogenous administration via blood products or parenteral iron, storage levels increase along with NTBI and LPI.

The development of iron overload is associated with increased morbidity and mortality.

NTBI and LPI play important roles in this process as storage iron in the form of ferritin and haemosiderin may be biologically inert.

To reduce the risks of morbidity and mortality, accurate documentation of iron load and treatment with iron chelators is required.

Whilst simple measures such as serum ferritin are useful, they are limited by a lack of specificity for iron per se.

Noninvasive measurement using MRI technology has emerged as an excellent method for accurate and specific measurement of iron stores, especially in the liver.

Chelators have been the principle methods of reduction of iron stores in secondary iron overload related to haematological disorders.

These have evolved from parenteral to oral therapies, with the greatest recent advance being the development of deferasirox（Exjade, Novartis）.

A combination of early assessment of iron overload and early introduction of iron chelation offer the best prospects for prolonged survival in patients with secondary iron overload.