High ferritin: what a raised ferritin result means and what happens next

Ferritin is the protein in which the body keeps spare iron. Most of it sits inside cells, and only a small amount circulates in the blood. Lab Tests Online UK explains that most ferritin is located within the cells of the body, with only a small amount in the blood, and that the blood level is used as an indicator of how much iron is stored.

The test is most often requested when a doctor suspects too little iron, because low ferritin is the most useful indicator of iron deficiency. It is also requested when too much iron is suspected, for example in someone with a family history of haemochromatosis. Because the result is so often found by chance on a general panel, many people are surprised by a high figure they have no symptoms to match.

A raised ferritin has two broad explanations. The first is a genuine increase in the body iron stores, known as iron overload. Lab Tests Online UK says ferritin levels are high in states of long-term iron overload, especially in haemochromatosis. Iron overload can also follow repeated blood transfusions, excess iron supplementation and liver disease linked to alcohol.

The second explanation is that the ferritin is raised even though total body iron is normal. Lab Tests Online UK says that when organs that contain ferritin are damaged, especially the liver, spleen and bone marrow, ferritin levels can become raised even though the total amount of iron in the body is normal. For this reason it describes ferritin as a less useful indicator of iron status in people with liver disease, long-term infections, cancer or autoimmune diseases.

In practice, most people with a mildly raised ferritin turn out to have an inflammatory, liver or metabolic explanation rather than an inherited iron condition. That is why doctors rarely act on one ferritin figure alone.

• Inherited iron overload (haemochromatosis).

• Inflammation or infection, which can push ferritin up temporarily.

• Liver disease, including alcohol-related liver disease.

• Repeated blood transfusions or excess iron from supplements.

• Other long-term illness such as cancer or autoimmune disease.

Many people with high ferritin have no symptoms at all. When iron overload is present, the NHS lists symptoms of haemochromatosis that include feeling very tired all the time, weight loss, weakness, joint pain, erectile dysfunction, irregular or missed periods, and brain fog, mood swings, depression and anxiety. The NHS says symptoms usually start between the ages of 30 and 60.

These symptoms are non-specific and have many other causes, which is a further reason a single high ferritin does not settle the question. Lab Tests Online UK notes that the most common symptom of iron overload is joint pain, and that some people have no symptoms.

The usual next step is to repeat the ferritin together with an iron measurement and transferrin saturation, which shows how much of the iron-carrying protein is occupied. The NHS lists the tests used to diagnose haemochromatosis as a full blood count, a liver test, a transferrin saturation test and a serum ferritin test. If those suggest haemochromatosis, a genetic test checks whether your DNA carries the gene associated with the condition.

A GP will also usually ask about alcohol intake, medicines and supplements, recent infection or illness, and weight and metabolic health, because these all alter ferritin. A repeat sample taken when you are well, and sometimes fasting, can show whether the first figure was a one-off. The NHS says that if tests detect a problem you will usually be referred to a hospital specialist.

If haemochromatosis is confirmed, the NHS says further tests may check for organ damage, particularly to the liver, and may include a liver ultrasound (Fibroscan) or MRI, an ECG or echo for the heart, and checks for diabetes and bone density.

Treatment depends on the cause. If the raised ferritin reflects inflammation, alcohol, fatty liver or medicines, the focus is on dealing with that cause, and the ferritin often falls on its own. No iron-lowering treatment is needed when body iron is normal.

For haemochromatosis, the NHS says there is currently no cure but there are treatments that reduce the amount of iron in the body. The two main treatments are venesection (also called phlebotomy), in which some blood is removed, weekly at first and then 2 to 4 times a year for life, and chelation therapy with medicine if regular blood removal is not easy. The NHS says you do not need to make big changes to your diet, but you will usually be advised to avoid breakfast cereals with added iron, iron or vitamin C supplements and too much alcohol.

Lab Tests Online UK adds that if you have hereditary haemochromatosis, taking extra iron can cause more rapid iron accumulation. If you are taking an iron supplement, mention it to your GP before the repeat test.

Book a routine appointment to discuss a high ferritin, especially if you also have persistent tiredness, joint pain or the other symptoms above, or if a parent, brother or sister has haemochromatosis. The NHS says you should see a GP if a parent or sibling has haemochromatosis, even if you have no symptoms, because tests can show whether you are at risk.

Seek prompt medical advice if a high ferritin is accompanied by yellowing of the skin or eyes, severe abdominal pain, chest pain or breathlessness. For sudden severe symptoms call 999 or go to A&E.

The outlook is generally good when the cause is found. The NHS says that if haemochromatosis is diagnosed and treated early it does not affect life expectancy, whereas if it is not found until it is advanced, high iron can lead to complications such as liver scarring (cirrhosis) or liver cancer, diabetes, arthritis and heart failure. That is the main reason an unexplained high ferritin should not simply be ignored.

For most other causes, the result is a prompt to review alcohol, weight, medicines and long-term conditions. Haemochromatosis UK is the patient-run UK charity the NHS points to for information and support.