-
Streptococcus pneumoniae, which can cause pneumonia and bloodstream infections.
-
Haemophilus influenzae type b, which can cause serious infections.
-
Neisseria meningitidis, which can cause meningitis and bloodstream infections.
The spleen helps the immune system recognize these organisms and produce an effective response.
This explains why people who have had their spleen removed, or whose spleen does not function properly, have a higher risk of certain severe infections.
Storing Platelets and Blood Cells
The spleen normally contains a reserve of platelets, which help blood clot after an injury.
It also contains immune cells and other components involved in blood filtration.
When the spleen becomes enlarged, it can hold an unusually large proportion of circulating blood cells. This process is known as sequestration.
As a result, fewer platelets, red blood cells, or white blood cells may remain available in the bloodstream.
Helping Maintain Blood Quality
The spleen does more than remove old red blood cells.
It also helps identify certain abnormal blood cells and remove cellular debris and microorganisms from circulation.
This makes it an important part of the body's blood maintenance system.
3. What Is an Enlarged Spleen?
An enlarged spleen is medically known as splenomegaly.
It is not a disease by itself. Instead, it is a physical finding that may occur because of an infection, liver disease, blood disorder, immune condition, or another underlying problem.
A normal spleen is usually not felt during a routine abdominal examination. When it becomes enlarged, a healthcare professional may sometimes feel it beneath the left rib cage.
However, physical examination alone cannot reliably determine the size or cause of an enlarged spleen.
Imaging tests, especially ultrasound, are often used to confirm the finding.
Some people with splenomegaly experience no symptoms at all. The enlargement may be discovered unexpectedly during an examination or imaging test performed for another reason.
Others may develop discomfort or symptoms related to changes in blood cell counts.
4. Early Warning Signs That Deserve Attention
The symptoms of spleen enlargement are often subtle and nonspecific.
They do not prove that the spleen is responsible, but persistent or unexplained symptoms should be discussed with a healthcare professional.
Pain or Pressure Beneath the Left Ribs
One possible symptom is discomfort in the upper-left abdomen.
People may describe it as:
-
A dull ache beneath the left rib cage.
-
A feeling of pressure or heaviness.
-
Discomfort that becomes more noticeable when taking a deep breath.
-
Pain that occasionally extends toward the back.
An enlarged spleen can stretch the capsule surrounding the organ, producing discomfort.
However, pain in this area can also come from the stomach, pancreas, colon, left kidney, muscles, or ribs.
Sudden or severe pain should never be assumed to be ordinary spleen enlargement.
Pain That Spreads to the Left Shoulder
Pain from irritation beneath the diaphragm can sometimes be felt in the left shoulder.
This is called referred pain.
In certain situations, left shoulder pain may occur when blood from an injured spleen irritates the diaphragm.
This can be a warning sign of internal bleeding, particularly after an abdominal injury.
If sudden left shoulder pain occurs together with abdominal pain, dizziness, weakness, or fainting after trauma, seek emergency medical care.
Feeling Full After Eating Small Meals
An enlarged spleen may press against the stomach.
As a result, a person may feel full after eating only a small portion of food.
This symptom is sometimes called early satiety.
For example, someone who previously ate a full meal without difficulty may begin feeling uncomfortable after only a few bites.
Early satiety is not specific to spleen disease. Stomach disorders, digestive conditions, and other abdominal problems can produce similar symptoms.
Nevertheless, persistent early satiety, especially when accompanied by unexplained weight loss or abdominal discomfort, deserves medical evaluation.
Unexplained Fatigue
Fatigue can occur when an enlarged spleen traps or removes too many red blood cells.
If the red blood cell count becomes low, anemia may develop.
Anemia reduces the blood's ability to carry oxygen efficiently. People may experience:
-
Persistent tiredness.
-
Weakness.
-
Shortness of breath during activity.
-
Headaches.
-
Dizziness.
-
Pale skin.
These symptoms have many possible causes, including iron deficiency, vitamin deficiencies, chronic inflammation, and blood disorders.
A blood test is necessary to determine whether anemia is present.
Frequent or Unusual Infections
The spleen contributes to immune defense.
When it is removed or does not function properly, the body becomes less effective at fighting certain bacterial infections.
However, frequent colds do not automatically indicate a spleen problem.
Most common respiratory infections are caused by viruses and occur for many reasons.
More concerning situations include a history of splenectomy, known spleen dysfunction, or repeated serious bacterial infections.
People without a functioning spleen should receive specific preventive care and medical advice about fever.
5. More Serious Symptoms Linked to Blood Cell Changes
An enlarged spleen may trap or destroy too many circulating blood cells. This can affect several parts of the body.
Easy Bruising
Platelets help blood clot.
When platelet levels become too low, a person may notice bruises appearing more easily than usual.
Other signs can include:
-
Small red or purple spots beneath the skin.
-
Bleeding gums.
-
Frequent nosebleeds.
-
Bleeding that takes longer than expected to stop.
These symptoms are not specific to spleen disease. Medication effects, immune conditions, liver disease, and bone marrow disorders can also reduce platelet counts.
Unexplained bruising or bleeding should be medically assessed.
Do not stop prescribed blood-thinning medication without speaking to the clinician who prescribed it.
Pale Skin and Shortness of Breath
A low red blood cell count can cause anemia.
The body may respond by increasing the heart rate and breathing rate to deliver enough oxygen to tissues.
Some people notice:
-
Pale skin or pale inner eyelids.
-
Breathlessness when climbing stairs.
-
A racing heartbeat.
-
Weakness.
-
Reduced exercise tolerance.
Severe or sudden breathlessness, chest pain, or fainting requires urgent assessment.
Fever and Persistent Illness
Infection is one possible cause of spleen enlargement.
For example, certain viral illnesses can cause temporary swelling of the spleen while the immune system responds to infection.