Desferal

Definition

Hemochromatosis is an inherited blood disorder that causes the body to retain excessive amounts of iron. This iron overload can lead to serious health consequences, most notably cirrhosis of the liver.

Description

Hemochromatosis is also known as iron overload, bronze diabetes, hereditary hemochromatosis and familial hemochromatosis. The inherited disorder causes increased absorption of intestinal iron, well beyond that needed to replace the body's loss of iron. Iron overload diseases afflict as many as 1.5 million persons in the United States. The most common of these, as well as one of the most common genetic disorders in the United States, is hereditary hemochromatosis. Men and women are equally affected by hemochromatosis, but women are diagnosed later in life because of blood loss from menstruation and childbirth. It most commonly appears in patients between the ages of 40-60, since it takes many years for the body to accumulate excessive iron.

Hemochromatosis causes excess iron storage in several organs of the body including the liver, pancreas, endocrine glands, heart, skin, and intestinal lining. The buildup of iron in these organs can lead to serious complications, including heart failure, liver cancer, andcirrhosis of the liver. It is estimated that about 5% of cirrhosis cases are caused by hereditary hemochromatosis.

Idiopathic pulmonary hemosiderosis, a disorder afflicting children and young adults, is a similar overload disorder characterized by abnormal accumulation of hemosiderin. Hemosiderin is a protein found in most tissues, especially the liver. It is produced by digestion of hematin, an iron-related substance.

Causes & symptoms

Hereditary hemochromatosis is passed by an autosomal recessive trait on the genes. (Scientists have recently identified the precise gene.) Because of its hereditary nature, as many as 25% of the siblings of hemochromatosis patients will also develop the disorder.

The symptoms of hemochromatosis include fatigue, weight loss, weakness, shortness of breath, heart palpitations, chronic abdominal pain, and impaired sexual performance. The patient may also show symptoms commonly connected with heart failure, diabetes or cirrhosis of the liver. Changes in the pigment of the skin may appear, such as grayness in certain areas, or a tanned or yellow (jaundice) appearance.

Idiopathic pulmonary hemosiderosis may first, and only, appear as paleness of the skin. Sometimes, the patient will experience spitting of blood from the lungs or bronchial tubes.

Diagnosis

The most common diagnostic methods for hemochromatosis are blood tests and computed tomography scan (CT scan). In recent years, CT scans with quantitative assessment of iron concentration has almost eliminated the need for liver biopsy. Blood tests will measure excessive iron levels. Concentrations of transferrin, a protein that transports iron and liver enzymes will also be measured. Serum ferritin and iron saturation are the best screening tests. Another test that measures an iron protein complex. In some cases, DNA testing for certain indications that young siblings will develop the disease will be conducted. X-ray studies of the liver, pituitary gland, and other iron absorbing organs may reveal abnormal iron deposits. CT scans, or magnetic resonance imaging (MRI) are the exams of choice for these studies.

Once a physician has identified signs of hemochromatosis with blood tests, a liver biopsy may be necessary. This involves insertion of a thin needle into the liver while the patient is under local anesthesia. The needle will extract a small amount of liver tissue, which can be analyzed microscopically to measure its iron content and other signs of hemochromatosis. Diagnosis of idiopathic pulmonary hemosiderosis begins with blood tests and x-ray studies of the chest.

Treatment

Patients who show signs of iron overload will often be treated with phlebotomy. Phlebotomy is a procedure that involves drawing blood from the patient, much like blood donation. Its purpose as a treatment is to rid the body of excess iron storage. Patients may need these procedures one or two times a week for a year or more. Less frequent phlebotomy may be continued in subsequent years to keep excess iron from accumulating. Patients who cannot tolerate phlebotomy due to other medical problems can be treated with Desferal (desferrioxamine). Diet restrictions may also be prescribed to limit the amount of iron ingested. Individuals who know they have the genetic makeup for hemochromatosis may postpone its onset by limiting iron intake and avoiding iron supplements. Complications from hemochromatosis, such as cirrhosis or diabetes, may also require treatment. Treatment for idiopathic pulmonary hemosiderosis is based on symptoms.

Alternative treatment

Diet restrictions may help lower the amount of iron in the body, but may not be enough to prevent or treat hemochromatosis. Patients who know they have the hereditary markers for the disease may limit iron-rich foods such as liver, red meat and iron-fortified cereals help keep iron levels down.

Prognosis

With early detection, the prognosis is usually good, particularly if the patient has worked aggressively to deplete iron before symptoms began. However, if left untreated, complications may arise which can be fatal. These include liver cancer, liver cirrhosis, diabetes mellitus, and failure to achieve iron depletion through phlebotomy. The prognosis for patients with idiopathic pulmonary hemosiderosis is fair, depending on detection and complications.

Prevention

Screening for hemochromatosis has become more cost effective, particularly for certain groups of people. Relatives, especially siblings, of patients with hemochromatosis should be tested for genes that indicate predisposition to the disease. Those relatives can begin to take measures to reduce iron intake or deplete iron stores prior to onset of symptoms.

Key Terms

Autosomal

From autosome, or a chromosome other than one of the sex chromosomes. Autosomal recessive traits, then are connected with other than the male/female chromosomes.

Cirrhosis

Hardening of an organ, usually the liver. Cirrhosis of the liver is a progressive disease which leads to destruction of liver cells, interference with blood flow in the liver and interference with the function of the liver.

Diabetes mellitus

The clinical name for common diabetes. It is a chronic disease caused by insufficient production of insulin or inability of the body to use insulin.

Phlebotomy

The taking of blood from the body through an incision in the vein, usually in the treatment of disease.

Further Reading

For Your Information

Periodicals

• Chazin, Suzanne. "Is Iron Making You Sick?" Readers Digest, (October 1995).
• Wolfe, Yun Lee. "Case of the Ceaselss Fatigue" Prevention Magazine, (July 1997):88.

  Organizations

• American Hemochromatosis Society, Inc. 777 E. Atlantic Ave., Z-363, Delray Beach, FL 33483-5352. http://www.americanhs.org.
• Hemochromatosis Foundation, Inc. P.O. Box 8569, Albany, NY 12208-0569. (518)489-0972.
• Iron Overload Diseases Association, Inc. 433 Westwind Drive, North Palm Beach, FL 33408. (407)840-8512.

Gale Encyclopedia of Medicine. Gale Research, 1999.