Hereditary haemochromatosis explained

What haemochromatosis is

Normally the gut carefully controls how much iron it absorbs, keeping levels steady. In hereditary haemochromatosis, a change in a gene disturbs this control, so the body keeps absorbing iron even when it already has enough. There is no easy way for the body to get rid of the extra iron, so it builds up slowly over decades and is stored in organs such as the liver, heart, pancreas and joints. The most common form in the UK is linked to a gene called HFE, and the condition is more common in people of northern European background. Someone usually needs to inherit a faulty copy from both parents to be at risk, and even then not everyone who carries the genes goes on to develop iron overload.

Symptoms and why it is missed

Haemochromatosis is easy to miss because the early symptoms are vague and common. People may feel persistently tired, notice aching joints — often in the knuckles — or have a lower sex drive. As iron builds up further, it can cause liver problems, diabetes, a bronze or grey tint to the skin, and heart rhythm or pumping problems. Symptoms usually appear in mid-life, and tend to show earlier in men, because women lose some iron through periods and pregnancy. Because tiredness and joint aches have so many causes, the condition is often overlooked for years. This is why doctors think of it in anyone with unexplained fatigue, joint pain, liver test abnormalities or a family history of the condition.

How it is diagnosed

Diagnosis usually starts with simple blood tests that measure how much iron is in the blood and how much is stored in the body — typically transferrin saturation and ferritin. If these suggest iron overload, a genetic blood test can look for the changes in the HFE gene that cause the common form. Sometimes further tests are used to check how much iron has built up in the liver and whether it has caused any damage, including specialised scans and, occasionally, a liver biopsy. Because the condition runs in families, close relatives of someone diagnosed are often offered testing too, so that anyone affected can be found and treated before iron overload causes harm. Finding it early makes a real difference to long-term health.

How it is treated

The main treatment is beautifully simple: removing blood regularly, in the same way as giving a blood donation, which is called venesection. Each time blood is taken, the body uses up some of its stored iron to make new red cells, gradually lowering the iron overload. At first this is done fairly often to bring iron levels down, then less often to keep them in a healthy range for life. Blood tests guide how frequently it is needed. People are usually advised to avoid iron and high-dose vitamin C supplements, to be sensible with alcohol to protect the liver, and to take care with raw shellfish. With treatment started before organ damage develops, many people have a normal life expectancy.

Living well and monitoring

Haemochromatosis is a lifelong condition, but for most people it is well controlled with regular venesection and check-ups. Ongoing care usually includes blood tests to keep iron levels in target and to watch the liver, along with monitoring for the conditions iron overload can cause, such as diabetes or joint and liver problems. If organ damage has already occurred, that is managed alongside the iron removal. Because it is inherited, discussing testing with family members is an important part of care. The practical message is hopeful: this is an inherited condition that is genuinely treatable, and the earlier it is found and iron is brought under control, the better the outlook.