Spleen

The spleen explained

The spleen is located on the left side of the abdomen and weighs around 200g in the average healthy adult. The spleen can be considered as two organs in one. It filters the blood and removes abnormal cells (such as old and defective red blood cells), and it makes disease-fighting components of the immune system (including antibodies and lymphocytes).

Since the spleen is involved in so many bodily functions, it is vulnerable to a wide range of disorders. However, the human body adapts well to life without this organ, so surgically removing a diseased or damaged spleen is possible without causing any serious harm to the person.

Spleen structure

The body of the spleen appears red and pulpy, surrounded by a tough capsule. The red pulp consists of blood vessels (splenic sinusoids) interwoven with connective tissue (splenic cords). The red pulp filters the blood and removes old and defective blood cells. The white pulp is inside the red pulp, and consists of little lumps of lymphoid tissue.

Antibodies are made inside the white pulp. Similarly to other organs of the lymphatic system, particular immune cells (B lymphocytes and T lymphocytes) and blood cells are either made or matured inside the spleen. Blood enters the spleen via the splenic artery, which subdivides into many tiny branches. Each branch is encased in a clump of lymphocytes, which means every drop of blood is filtered for foreign particles as it enters the spleen.

Disorders of the spleen

Some of the disorders that can affect the spleen include:

• Splenomegaly (enlarged spleen)
• Hypersplenism
• splenic rupture (traumatic/atraumatic).
• Blood disorders
• Cancers – solid organ, blood.
• Cysts and tumours
• CAS, Congenital absence of the spleen
• Hyposplenism

Splenomegaly

A variety of disorders can cause the spleen to enlarge, sometimes to 2kg or more. Any conditions that cause a rapid breakdown of blood cells, such as haemolytic anaemias, can place great strain on the spleen and as a consequence, make it enlarge. Other causes of splenomegaly include infections (such as glandular fever), liver disease and some cancers (such as Hodgkin’s disease, leukaemia and lymphoma).

Hypersplenism

The two characteristic features of hypersplenism are splenomegaly and a deficiency of one or more blood components. It seems that an enlarged spleen is sometimes overactive and will destroy more blood cells than necessary.

Symptoms depend on which blood component is lacking. For example, if red blood cells are deficient, anaemia will be the result (with symptoms including fatigue and pallor). Most cases of hypersplenism are caused by disorders somewhere else in the body, such as cirrhosis of the liver.

Splenic rupture

Certain disorders, including glandular fever, can occasionally make the enlarged spleen delicate enough to spontaneously rupture. A sudden blow to the left side of the abdomen can split the outer capsule of the spleen and cause bleeding into the abdominal cavity. There are various degrees of splenic rupture. When bleeding is life threatening, surgery to remove the spleen (splenectomy) is needed. Sometimes the spleen can be saved by placing a synthetic clot into the splenic artery, this is called a splenic artery embolisation.

Blood disorders

Some examples include:

• ITP
• Thalassaemia
• Autoimmune Haemolytic anemia
• Haemolytic anemia

Cancers – solid organ

• Pancreatic
• Renal
• Stomach
• Colorectal
• Oesophageal
• PMP – Pseudomyxoma Peritonei
• GIT stromal Tumours

Cancers - blood

• Leukaemia
• Hodgkins lymphoma
• Non Hodgkins lymphoma

Cysts/Tumours

Cysts in the pancreas or spleen

Hyposplenism

Hyposplenism or a non functioning spleen, is usually diagnosed by a haematologist or specialist and reasons can include:

• Congenital disorders (heart defects, polysplenia)
• Haematological disorders
• Cancer or treatment for cancers
• Coeliac disease
• Autoimmune disorders
• Splenic infarction

Congenital absence of the Spleen (CAS)

Sometimes people can be born without a spleen and this condition is known as congenital asplenia. This may be diagnosed at birth or incidentally later in life via a scan.

Pancreatic Surgery

It is very important to note that when the pancreas or part thereof is removed, the spleen is also surgically removed in most cases. The spleen and pancreas are anatomically placed that they are touching and share some vascular tissue, this accounts for why the spleen may be removed. Removal of the spleen with the pancreas or part thereof avoids risky post operative bleeding.

Diagnosis of spleen disorders

Depending on the condition under investigation, disorders of the spleen can be diagnosed using a number of tests, including:

• physical examination
• blood tests
• ultrasound
• computed tomography (CT) scan
• bone marrow biopsy
• other tests to check for underlying disorders.
• MRI or PET scan.

Treatment for spleen disorders

Treatment depends on the disorder and its specific cause. For example, if the splenomegaly is caused by particular cancers (including Hodgkin’s disease, leukaemia or lymphoma), then treatment will focus on eliminating or controlling the primary disease.

Hypersplenism, triggered by cirrhosis of the liver, can be treated with abstinence from alcohol and special dietary modifications. A severely ruptured spleen is usually surgically removed.

Recovery after splenectomy

The surgical removal of the spleen is called a splenectomy. The body can cope without the spleen, although the person might be more susceptible to infections after the operation. Their blood may also contain odd-shaped red blood cells. In some cases, it is possible to remove only the diseased or damaged parts of the spleen. This allows the remaining healthy portions to keep functioning as normal.

Infection, immunisations and splenectomy

People who have had their spleen removed or have a spleen disorder are at increased risk of infection, most commonly pneumococcal and meningococcal infections. Whilst they are rare, they can develop into severe infections (sepsis) without prompt intervention. Vaccines are recommended especially for these and they should be discussed with a doctor.

They are:

• pneumococcal vaccine
• meningococcal vaccines
• haemophilus influenzae type b vaccine - recommended for people over 5 years with a spleen disorder or have had their spleen removed if they were not fully vaccinated in early childhood.

These vaccines are available for free under the National Immunisation program for people with these specified conditions, and are available to access through your GP or immunisation provider.

Viral infections

It should be noted that people without a spleen are not at increased risk of contracting viral infections such as the flu (influenza) and COVID-19. However, if you do get a virus, you increase the chance of a secondary bacterial infection. We do actively encourage people without a spleen to have the annual fluvax (as per age range) and COVID vaccines as recommended by ATAGI.

Antibiotics

Low dose prophylactic antibiotics are prescribed post splenectomy, usually a penicillin based antibiotic unless there are recorded allergies. These can be prescribed for several years or lifelong depending on your medical history and do work to protect you from some bacterial infections.

People who are otherwise immunocompromised (having chemotherapy or taking steroids) are recommended by their specialist to take them for a longer period. It is recommended you see a specialist immunologist if you have a penicillin allergy so this can be reviewed under supervised conditions. Penicillin is one of the most important antibiotics for treating infections in people without a spleen.

Emergency antibiotics

These are prescribed in case you feel unwell and cannot immediately (within 4-6 hours) be assessed by a GP or ED doctor. It is important that if you take your emergency antibiotics that it would always be followed up with an assessment from a medical officer.

Post splenectomy

Be alert, not alarmed post splenectomy. The most important thing to watch out for is any signs or symptoms of infection:

• Fevers
• Vomiting/Diarrhoea
• Shivers/sweats/shakes
• Confusion
• Severe headaches
• “Feeling very unwell”

If you experience these symptoms, seek medical attention immediately (GP or hospital emergency department). If you know medical attention will be delayed, take your prescribed emergency antibiotics then seek medical attention as soon as possible.

People without a Spleen can get really sick, very quickly if you ignore these symptoms. Early antibiotic intervention can prevent an unnecessary hospital stay for those without a spleen.

Always tell your GP that your spleen is absent or not working and utilise your medical alert card or emergency alerts on your phone.

Animal/tick bites or scratches

Dogs and cats have a bacteria in their mouth that people without a spleen are very susceptible to, Capnocytophaga canimorsus.

This bacteria can be harmful in people without a functioning spleen. If you get bitten or scratched, immediately wash the area with an antiseptic or soap and monitor for any signs of infection (redness, swelling). Seek medical attention if you suspect an infection.

Travel advice

See a travel doctor before going overseas. There are some counties where malaria is prevalent. It is spread from humans via mosquitoes so use of mosquito repellent and barrier clothing and prophylactic anti-malarial medication is warranted. Always travel with your daily antibiotics (if you take them) and very importantly a supply of emergency antibiotics. Seek immediate medical attention if unwell.

Where to get help

• Your GP (doctor) or clinic nurse
• Spleen Australia, Alfred Hospital. Tel. (03) 9076 3828. If you have had your spleen out or are diagnosed with hyposplenism by your specialist, you can register with the Spleen Australia clinical service. Spleen Australia are funded by each state government to provide care to residents of Victoria, Tasmania, Queensland and Western Australia. If you are a resident of these states, your GP or hospital medical officer can register you via our website. Self-referral is encouraged. All patients receive a telephone education session from a trained spleen nurse. Additional health information is sent to you, your GP and where appropriate your family. An individualised vaccine and antibiotic plan will be developed based on current Australian medical recommendations.