Overview: What is hemochromatosis?
The body urgently needs iron to build new red blood cells. In iron storage disease, however, the body absorbs more iron than it needs for blood production. Normally, the body automatically regulates how much iron enters the bloodstream via the intestinal mucosa. In healthy people, this amounts to one to two milligrams of iron a day. They are then excreted through sweat, stool or urine. In hemochromatosis, however, the intestine absorbs around three to four milliliters of iron per day. The excess iron is deposited in the liver and joints, and more rarely in the pancreas, heart and pituitary gland. If an iron storage disease remains undetected, it can have serious physical consequences. The disease can lead to irreparable damage to organs, such as the liver or joints.
Some people suffer from hereditary iron overload, namely hereditary hemochromatosis.
Iron storage disease: inherited or acquired
Hereditary hemochromatosis is inherited in an autosomal recessive manner, i.e. when both parents pass on the genetic defect to their child. The HFE gene is most frequently affected, a gene that influences the formation of proteins responsible for iron absorption. It is the most common hereditary disease in Europe, affecting men more often than women. Hereditary haemochromatosis is usually diagnosed between the ages of 40 and 60. In very rare cases, it occurs before the age of 30 (juvenile haemochromatosis) or even in the womb (neonatal haemochromatosis).
Not everyone with the genetic defect develops iron overload; this is most likely due to additional environmental factors and/or any other genetic changes. Hereditary haemochromatosis therefore usually only becomes apparent in the course of adult life. Men usually develop iron overload earlier than women. This is because women lose iron both through menstruation and during pregnancy.
Hemochromatosis: causes and risk factors
There is no way to prevent inherited hemochromatosis. At best, those affected can try to consume less iron with their food. Red meat, pulses such as lentils and beans, nuts and wholegrain products contain a lot of iron. Those affected should also avoid alcohol. If you are planning to have children, you may be able to find out whether both partners have the right gene by means of family screening. This is triggered by the gene sections C282Y and H63D on the HFE gene – here the FE of “Ferrum” (iron) already indicates the significance of the gene.
Acquired (secondary) iron overload
In the case of acquired iron overload, the iron oversupply is typically caused by excessive iron intake (most frequently through blood transfusions or less frequently through direct iron administration), liver diseases (such as hepatitis, alcohol-related liver damage) or hematopoietic diseases (including thalassemia).
- Hepatitis B and C
- Frequent blood transfusions
- Metabolic diseases such as porphyria cutanea tarda
- Childhood anemia due to a disorder of hemoglobin formation (thalassaemia major)
- Inherited disorder of iron incorporation (sideroblastic anemia)
- Increased breakdown of red blood cells (hemolytic anemia)
Symptoms of hemochromatosis
Symptoms of haemochromatosis usually occur in adulthood, in men after the age of 40 and later in women. The first signs are rather unspecific, such as tiredness, weakness or joint pain. Untreated hemochromatosis leads to further, sometimes serious, consequential damage as a result of iron deposition:
Iron storage disease: diagnosis with us
The first indication of iron overload is primarily an increased iron level in the blood, including various proteins that are responsible for iron transport and storage (including ferritin, transferrin saturation). Depending on the constellation of iron levels, this may indicate the presence of hereditary hemochromatosis. If this is the case, we will suggest a genetic test. This determines whether the typical gene mutations of iron storage disease are present.
Depending on the severity of the iron overload, imaging such as magnetic resonance imaging or an ultrasound of the heart may be suggested, and rarely a liver biopsy. If acquired causes of iron overload are suspected, we also carry out further clarifications depending on the laboratory constellation (e.g. search for liver diseases, search for blood formation diseases).
Haemochromatosis: prevention, early detection, prognosis
It is important to recognize hereditary haemochromatosis early, as early treatment can prevent consequential damage. Nowadays, hereditary haemochromatosis is often diagnosed in young adulthood because a family member is already affected. Around three out of four patients with hereditary haemochromatosis are therefore diagnosed before symptoms appear.
The earlier an iron storage disease is detected, the better it is for the patient. This is because the disease does not cause any damage at the beginning. If the genetic defect in haemochromatosis is discovered in childhood or adolescence and the affected person is examined closely and treated if necessary, the disease poses no danger or restriction. However, if the body stores iron over a longer period of time without the problem being recognized, the damage can no longer be repaired. In the latter case, the quality of life or, in extreme cases, even the lifespan can be significantly reduced. Liver cirrhosis in particular can lead to liver cancer and liver failure. However, even in the case of secondary iron storage disease, treatment may lead to a considerable improvement in quality of life.