The Spleen: What it Does and Why it is So Fragile

What the Spleen Does and Why We Can Live Without One

Female surgeon adjusting medical glove in hospital
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The spleen is one of the least understood organs of the human body.  Most people never think about the spleen unless it becomes damaged by trauma, but it performs multiple functions. The spleen participates in the creation of blood cells and also helps to filter the blood of old blood cells and fight infection. The spleen also helps to control the amount of blood circulating through the body by creating a reserve pool of blood that can be released during severe bleeding.


Unlike the heart and other organs, the spleen is rarely the cause of health issues so it is often overlooked when talking about wellness.  The spleen does contribute to overall good health, but it is also not an essential organ, which is a good thing because it can be fragile. 

The Spleen Is a Helper

The spleen works with other organs in the body to complete the tasks of blood storage, fighting infection and filtering the blood.  While the spleen is useful and does perform vital tasks, other organs in the body also work to filter the blood and fight infection, and blood cells are mainly produced in the bones.  It is this overlap makes it possible for the spleen to be removed without causing lasting harm to the individual. While most people are somewhat healthier with a spleen, it is absolutely possible to have a normal life without a spleen. 

The Fragile Spleen

The spleen holds reserve blood in case of significant bleeding, much like a blood filled balloon, and acts as a reserve source of extra blood.

 In a trauma situation, particularly a severe car crash where an individual is wearing a seat belt, the force of impact can actually cause the spleen to rupture.  The spleen has a high amount of blood flow, which can lead to a tremendous amount of bleeding.  When this happens, the treatment is a splenectomy, the surgery to remove the spleen.

The spleen can also become enlarged, stretching over time, until it becomes unable to function.  It can expand over time from normal size (which is approximately the size of a small chicken breast), to the size of a softball or approaching the size of a volleyball.  As a spleen becomes enlarged, it becomes more fragile and is more likely to be damaged in an accident.  

Living Without a Spleen

As the spleen is not the only organ responsible for any of these functions, the spleen is not a necessary organ. It is possible to have the spleen removed and live a healthy life.  Individuals without a spleen may be more likely to contract some types of infections as the body will have less B cells, the cells that "remember" exposure to bacterias and "remember" how to fight them.  

The risks of contracting an infection are highest in the first two years following surgery. Individuals who have had their spleen removed will need to tell healthcare providers that their spleen is absent, as they will always be at higher risk for infection.  It is important that a person without a spleen not ignore early signs of infection, such as a fever, as the body is more likely to require antibiotics to fight infection effectively.


In general, the person without a spleen will go on to have a healthy life.  That said, an individual without a spleen will always have a greater risk of contracting pneumonia and reduced effectiveness of vaccines.  Vaccines may need to be given more frequently, particularly the pneumonia vaccine, to prevent serious illness. A meningitis vaccine should also be considered along with annual flu shots

Also Known As: splenic--refers to the spleen.  There was a splenic laceration but it was not so severe that surgery was required for treatment.

Common Misspellings: splen, spleeen, splene, splean, spleenic

Examples: After the car accident it was determine that the spleen was damaged and had to be surgically removed.

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