Disorders of Iron Uptake

Disorders of Iron Uptake

Iron deficiency causes anemia. Conversely, iron overload

causes hemosiderin to accumulate in the tissues, producing

hemosiderosis.

damage tissues, causing hemochromatosis. This syndrome

is characterized by pigmentation of the skin, pancreatic

damage with diabetes (“bronze diabetes"), cirrhosis of the

liver, a high incidence of hepatic carcinoma, and gonadal

atrophy. Hemochromatosis may be hereditary or acquired.

The most common cause of the hereditary forms is a mutated

Large amounts of hemosiderin can

HFE

It is located on the short arm of chromosome 6 and is

closely linked to the human leukocyte antigen-A (HLA-A)

locus. It is still unknown precisely how mutations in

gene that is common in the Caucasian population.HFE

cause hemochromatosis, but individuals who are homogenous

for

HFE mutations absorb excess amounts of iron because

HFE

transporters that participate in iron uptake. If the abnormality

is diagnosed before excessive amounts of iron accumulate

in the tissues, life expectancy can be prolonged by

repeated withdrawal of blood. Acquired hemochromatosis

occurs when the iron-regulating system is overwhelmed by

excess iron loads due to chronic destruction of red blood

cells, liver disease, or repeated transfusions in diseases such

as intractable anemia.

normally inhibits expression of the duodenal