Anaemia is a shortage of red blood cells and haemoglobin. If you have anaemia, doctors say that you are ‘anaemic’.
Haemoglobin is a protein found in red blood cells. It carries oxygen from the lungs to the rest of the body. Red blood cells are made in the bone marrow (the spongy centre of some bones). They normally work for about 3 months before they wear out and are removed from the blood. The bone marrow is working all the time to make new red blood cells.
The amount of haemoglobin (and the number of red cells) in your blood is measured by a test called the full blood count (FBC). Doctors talk about a ‘range’ of normal results because some people naturally have higher or lower levels than do others. Men usually have more haemoglobin than women, so there are different ranges for men and women.
Different hospitals use slightly different ranges. A normal haemoglobin level is roughly:
- above 135 grams per litre of blood (g/L) for a man, and
- above 115 g/L for a woman.
These values used to be given as 13.5 g/dL and 11.5 g/dL (grams of haemoglobin per 100 millilitres of blood, instead of per litre).
The number of red blood cells and the amount of haemoglobin go up and down together. Doctors don’t usually mention the number of red blood cells when talking about anaemia.
Red blood cells contain haemoglobin, which is the protein that carries oxygen around the body. It is important that all organs and tissues of the body get enough oxygen; they cannot work properly without it.
When red blood cells pass in the bloodstream through the lungs, the haemoglobin picks up oxygen. These red blood cells then pass in the bloodstream around the rest of the body. As they do so, the haemoglobin releases its oxygen to the organs that need it.
If there are fewer red blood cells in the bloodstream, there is less haemoglobin. This means that less oxygen can be carried around the body to the organs that need it.
Possible causes of anaemia in people with lymphoma are:
- lymphoma in the bone marrow
- a side effect of treatment
- red blood cells being destroyed by an antibody that attacks them (this is known as 'autoimmune haemolytic anaemia’)
- other causes, some related to the lymphoma and its treatment, and other having nothing to do with the lymphoma.
If lymphoma cells are in the bone marrow, they take up space that is normally used to make healthy blood cells. This can lower the number of red blood cells your bone marrow makes, meaning you have less haemoglobin and become anaemic.
Anaemia caused by lymphoma in the bone marrow often starts to improve once treatment for the lymphoma has started to work.
Although the aim of treatment is to kill the lymphoma cells, a side effect of many types of chemotherapy, and some radiotherapy treatments (eg radiotherapy to the pelvis), is that some healthy cells are also destroyed. This may include blood cells that are developing in the bone marrow.
If chemotherapy stops new red blood cells being made, it usually doesn’t cause anaemia straightaway. Red blood cells live for 3 months, so there are still many older cells around when treatment starts. As the treatment goes on, the older cells start to wear out and be removed, while fewer new cells are being made. This means there is less haemoglobin in the blood and anaemia can start to be a problem. How much of a problem it becomes depends on:
- how strong your chemotherapy is
- whether you had lymphoma in the bone marrow before you started treatment
- whether you have additional problems, eg infection.
Radiotherapy doesn’t usually affect enough of the bone marrow to cause anaemia.
Sometimes the body’s immune system starts to make antibodies against cells of the body. These antibodies are known as ‘autoantibodies’.
If the autoantibodies stick to red blood cells, the cells are removed as they pass through the spleen. If the bone marrow can’t make new red cells fast enough to replace the ones lost, anaemia develops. This type of anaemia is known as ‘autoimmune haemolytic anaemia’ (AIHA). It happens more often in people with low-grade lymphomas, such as chronic lymphocytic leukaemia (CLL).
Other ways that lymphoma and its treatment can cause anaemia include:
- bleeding, which might happen if you have lymphoma in the bowel, or if you have low platelets (thrombocytopenia)
- lack of certain vitamins, which may happen if you are not eating well
- anaemia of chronic disease, which is when the bone marrow makes new cells more slowly because of an infection or an inflammation that’s been in the body for a long time.
Many people with a haemoglobin level below normal do not notice anything different. This is because the body has a built-in reserve with much more haemoglobin than is needed for day-to-day life. If your haemoglobin is only slightly low, you can tolerate your anaemia.
As the amount of haemoglobin falls, the organs of the body receive less oxygen. Symptoms start to occur if parts of the body reach a point of not getting enough oxygen. This is when you stop tolerating your anaemia.
Symptoms of anaemia include:
- fatigue (extreme tiredness)
- feeling weak and lethargic (lacking energy)
- feeling short of breath when doing things
- feeling your heart fluttering or pounding (palpitations)
- feeling dizzy or faint
- headache or sometimes aching bones.
If you have anaemia, your complexion might look paler than is normal for you.
People vary in how much anaemia they can tolerate. How you feel depends on:
- your age
- your fitness
- whether or not you have any other conditions, such as heart disease.
Having lymphoma means you might notice symptoms of milder anaemia (less of a fall in your haemoglobin) than you would have done otherwise. The draining effects of having lymphoma and its treatment can make you less able to tolerate your anaemia. Also, if you get an infection or fever, your anaemia could worsen and you might feel the effects of it more.
Let your medical team know if you notice any of the symptoms. They are likely to suggest you have a blood test to check your haemoglobin level. Many of these symptoms can also be caused by problems other than anaemia. If your symptoms are due to anaemia, your doctor should talk to you about possible treatments.
Treatment for anaemia depends on its cause – often there is more than one. Your doctor is likely to first ask for other blood tests to find the reason for your low haemoglobin. Sometimes the cause is easy to treat and has nothing to do with your lymphoma.
For example, if your anaemia is caused by low iron, you might need a tablet to supplement your diet. Always check with your medical team before taking any medicines or supplements that haven’t been prescribed for you. An iron infusion can sometimes be needed. Your doctor will tell you if this is the case. If your anaemia is caused by loss of blood, you may have other tests to look for the source of the bleeding.
If your anaemia is caused by your bone marrow not making enough red blood cells, you’ll need treatment. You might be given a blood transfusion or erythropoietin (EPO) injections to boost your bone marrow.
These treatments don’t work well for autoimmune haemolytic anaemia. Instead, treatment for autoimmune haemolytic anaemia aims to lower the levels of the autoantibody.
If your anaemia is causing you serious symptoms, your doctor may talk to you about having a blood transfusion. In a blood transfusion, you are given enough blood to ease your symptoms – your haemoglobin may still not be back to its normal level. Sometimes 2 or 3 units (roughly a pint of blood each) are given at a time. Transfusion can take much of the day to complete.
Usually a transfusion will make you feel better for a few weeks. Afterwards, if your bone marrow still isn’t working well, you may begin to get symptoms again. This is because, just like your own cells, the transfused red cells are removed from your blood as they age.
Erythropoietin (EPO) is a hormone (a chemical messenger) that occurs naturally in your body. It is made by the kidneys and tells the bone marrow to make more red blood cells. It can also be made as a medicine that is given as a subcutaneous injection (an injection into the fatty tissue just under the skin).
EPO is sometimes given to people with cancer who are being treated with chemotherapy and have symptoms of anaemia. Trials have shown it often improves the anaemia. As a result, fewer blood transfusions are needed and people’s quality of life is better.
EPO is not suitable for everyone because of side effects, which include:
- raised blood pressure (hypertension)
- an increased risk of blood clots.
Other side effects include:
- nausea and/or diarrhoea
- pain and/or redness at the injection site
- oedema (swelling of tissues due to a build up of fluid).
The National Institute for Health and Care Excellence (NICE) recently updated its guidance on using EPO for people with cancer. EPO is now recommended as a possible treatment for anaemia in people having chemotherapy to treat cancer. If your doctors think you should consider this treatment, they will talk to you more about the potential benefits and risks.
If your anaemia is due to autoantibodies destroying your red cells, blood transfusions usually do not help. Instead, the treatment of this type of anaemia aims to reduce the number of autoantibodies being made. This is usually done, at least at first, by giving you treatment with steroids, often prednisolone. The dose of steroid is high to begin with, which may cause irritation to your stomach. You may be given another drug to protect your stomach. Once your red cells are no longer being destroyed, the dose of steroid is lowered.
Treating your lymphoma may also help to stop the autoantibodies being made. Rituximab(MabThera®), with or without chemotherapy, tends to reduce the number of autoantibodies as well as kill the lymphoma cells.