The spleen is a fist-sized organ found in the upper left side of your abdomen, behind your stomach and left ribs.
Some people are born without a spleen or need to have it removed because of disease or injury.
It's an important part of your immune system but you can survive without it, as the liver can take over many of the spleen's functions.
The spleen has a few important functions:
If the spleen doesn't work properly:
If the spleen needs to be removed, other organs such as the liver can take over many of the spleen's functions.
This means people without a spleen will still be able to cope with most infections, although there is a small risk that a serious infection may develop quickly – see What are the risks of not having a spleen?
An operation to remove the spleen, known as a splenectomy, may be needed if the spleen is damaged, diseased or enlarged.
The spleen can become damaged or may rupture (burst) after a forceful blow to the abdomen.
Rupture can happen straight away or it may happen weeks after the injury.
Signs of a ruptured spleen are:
A ruptured spleen is a medical emergency, as it can cause life-threatening bleeding. Go straight to your nearest hospital’s accident and emergency (A&E) department if you think you've ruptured or damaged your spleen.
Most at risk are children and adults with infections, people with diseases that affect the liver and spleen, and people who live in areas where malaria is a problem.
An enlarged spleen doesn't always cause symptoms. Otherwise, look out for:
The spleen is not usually removed if it's just enlarged. Instead, you'll receive treatment for any underlying condition and your spleen will be monitored. Antibiotics may be prescribed if there's an infection. You'll need to avoid contact sports for a while, as you'll be at greater risk of rupturing the spleen while it is enlarged.
Surgery is only necessary if the enlarged spleen is causing serious complications or if the cause can't be found.
If there's time, you'll be advised to have a series of immunisations before the operation.
Most splenectomies are carried out using a laparoscopy (keyhole surgery). This is a minimally invasive type of surgical procedure that allows a surgeon to access the inside of your abdomen without having to make large incisions in your skin.
Open surgery, where a larger incision is made, may be needed if the spleen is too large or too damaged to be removed via keyhole surgery.
Read information about having an operation.
It's normal to feel sore and be bruised after a splenectomy, but you'll be given pain relief medication. You may need to stay in hospital for a few days before you can go home.
Like any operation, a splenectomy carries a small risk of complications, including bleeding and infection. Your doctor will run through these risks with you, and explain the procedure in detail.
If you don’t have a working spleen, you can still cope with most infections, as the spleen is only one part of your immune system. However, there is a small risk that an infection can quickly become serious. This risk will be present for the rest of your life.
Young children have a higher risk than adults, but the risk is still small. The risk is also increased if you have a medical condition such as sickle cell anaemia, coeliac disease or a condition that affects your immune system, such as HIV.
This risk can be minimised by following simple precautions.
Make sure you have had all your routine childhood vaccinations. You should also be vaccinated against:
It's recommended that you take low-dose antibiotics for the rest of your life to prevent bacterial infections. Antibiotics are particularly important:
Watch out for signs of infection, such as:
Your doctor can prescribe a course of antibiotics for you to use if you get an infection. Start taking them at the first sign of an infection and see your doctor as soon as possible.
If your infection becomes serious, you will be admitted to hospital.
Bites from animals and ticks (small blood-sucking parasites) can cause infections.
If you get bitten by an animal, particularly a dog, start your course of antibiotics and seek medical advice urgently.
If you go trekking or camping regularly, you may be at risk of babesiosis, which is a rare disease transmitted by ticks. Try to avoid tick bites by wearing clothes that cover your skin, particularly long trousers. If you become ill, get medical advice straight away.
Healthcare professionals will mark your health records to show that you don't have a working spleen. However, always remember to tell any medical professionals that you consult, including your dentist.
It's a good idea to carry or wear some medical ID. For example:
If you need help or emergency treatment, your medical ID will alert the staff to your condition.
If you're travelling abroad:
People without a working spleen have an increased risk of developing a severe form of malaria. If possible, avoid countries where malaria is present. If you can't, speak to your doctor or local pharmacist about anti-malaria medicine before you travel. You should also use mosquito nets and insect repellent.
Important: Our website provides useful information but is not a substitute for medical advice. You should always seek the advice of your doctor when making decisions about your health.