February 9, 2023
February 9, 2023

Causes of an Enlarged Spleen: Mononucleosis and Beyond

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Causes of an Enlarged Spleen: Mononucleosis and Beyond

Key takeaways:

  • The spleen filters blood to maintain a healthy balance of red and white blood cells and platelets.
  • When reviewing causes of an enlarged spleen, mononucleosis is one to note.
  • Mononucleosis is identified by fatigue, fever, an enlarged spleen, and other symptoms.
  • A splenic rupture can be a life-threatening condition.
An MRI can detect splenomegaly (enlarged spleen) by assessing the blood flow through the spleen.

An enlarged spleen (splenomegaly) occurs when you have an underlying disease, such as infectious mononucleosis (mono).

Other causes include liver and autoimmune diseases and some kinds of cancer such as leukemia and lymphoma. Trauma from automobile accidents or contact sports can also cause an enlarged spleen.

Before we dive into spleen enlargement, let’s talk about your spleen, what it does for your body, and how it can become enlarged.

The spleen is an organ located on your abdomen’s upper left side, near your stomach. Its red, fleshy tissue is responsible for filtering your blood, while the white pulp tissue has an immunological function.

Your spleen produces white blood cells to clean your blood of dead tissue, bacteria, and foreign matter as they move through it. This wonderful organ also filters your blood for abnormal cells.

In this article, we’ll discuss common enlarged spleen symptoms and how it relates to mononucleosis (mono). We’ll also cover how to identify and treat mono, which should also help your spleen go back to normal.

What Happens When You Have Splenomegaly?

When it’s enlarged, your spleen starts to filter normal blood cells as well as abnormal blood cells. That means you have fewer healthy blood cells circulating in your bloodstream. This could result in a diminished oxygen supply to your body’s tissues and organs.

It will also result in too many platelets, which are responsible for blood clotting and may clog your spleen.

If left untreated, splenomegaly could tamper with the normal function of your spleen and even damage or destroy parts of the spleen itself.

Common Symptoms and Signs of an Enlarged Spleen

Often, people don’t feel any symptoms or signs of an enlarged spleen. An enlarged spleen is often found in the middle of a routine physical exam or annual, full-body MRI screening.

However, a swollen spleen can also cause some symptoms:

  • You may have indigestion or feel full because your spleen is compressing your stomach.
  • If your diaphragm is irritated, you may develop hiccups.
  • Pain in your upper abdomen may radiate to the back or shoulder blade.

That said, considering the causes of an enlarged spleen (mononucleosis and other viruses, diseases, or infections), symptoms from the illness aren’t always local to the abdomen. These symptoms may include fatigue, fever, and swollen lymph nodes in your armpits and neck — especially if you have mono.

Other symptoms of conditions that cause an enlarged spleen could include:

  • Weakness
  • Easily bruised and shortness of breath indicating anemia
  • Weight loss due to cancer
  • Fever due to infection
  • Jaundice, nausea, or vomiting resulting from liver disease

If you experience intense pain, seek emergency medical attention immediately by dialing 911. Your spleen may have ruptured, and the resulting internal bleeding can be life-threatening.

Diagnosing Splenomegaly: What To Expect

One may diagnose an enlarged spleen during a physical exam, in which your medical practitioner uses palpation and percussion to find your spleen. They may feel the spleen swelling through your skin.

To confirm your diagnosis, your clinician will likely order a complete blood count to determine your red and white blood cells and platelet levels.

They might also order an ultrasound or a CT scan to confirm your spleen’s size and if it’s crowding other organs.

Your doctor could also ask for a spleen MRI to trace the blood flow through your spleen.

MRI has an advantage over CT imaging because it doesn’t involve ionizing radiation. It can also look through the ribs that protect your spleen to give you clearer imaging.

Mononucleosis: One Cause of an Enlarged Spleen

The so-called kissing disease, infectious mononucleosis, or mono, can cause an enlarged spleen. Let’s dive into how mono spreads, how to identify it, and how to treat it.

The Epstein-Barr virus (EBV) causes mono. It spreads by saliva exchange, which may happen through kissing, sneezing or coughing, and sharing a glass, eating utensils, or even toothbrushes.

The incubation period for mono is 4-6 weeks. Although mono isn’t a severe disease, its characteristic fatigue can substantially impact the acute phase. The “acute phase” refers to your body’s quick response following bodily harm such as infection, tissue injury, and other issues.

How the Epstein-Barr Virus Relates

Epstein-Barr virus (EBV) is the name for human herpesvirus 4. Found globally, EBV is one of the most common human viruses. Nine out of 10 people have been or will become infected with Epstein-Barr during their lifetime. EBV is one of the most common viruses because it spreads by exchanging bodily fluids.

A monospot is a rapid test for EBV infectious mononucleosis. The test checks if you have an Epstein-Barr viral infection, which is the cause of your mononucleosis. This blood test detects heterophile antibodies, which form in response to antigens (toxins or foreign substances). External antigens, such as a virus or bacterial infection, initiate the development of heterophile antibodies.

Some other diseases and infections can also cause mono. These include cytomegalovirus, another type of herpes virus; toxoplasmosis, a parasitic infection; HIV; rubella, and hepatitis A, B, or C.

What Are the Symptoms of Mononucleosis?

Young children rarely show symptoms of mononucleosis, while young adults’ symptoms include:

  • Fatigue
  • Fever
  • Skin rash
  • Headache
  • Swollen tonsils
  • A sore throat, often misdiagnosed as strep throat
  • Swollen lymph nodes in armpits and neck
  • Enlarged spleen

Teens and young adults are likely to show all the symptoms of mono. Within a few weeks, the fever and sore throat will improve. However, enlarged lymph nodes, a swollen spleen, and fatigue may linger after other symptoms clear.

Treating Mono and a Resulting Enlarged Spleen

young woman piggy back hugging a young man

Even though mono lasts longer than a cold, the treatment is similar: bed rest, plenty of fluids, and NSAIDS (acetaminophen or ibuprofen) for pain and fevers.

Antibiotics, such as amoxicillin or penicillin, don’t work because mono is a viral infection rather than a bacterial infection. However, antiviral medications also aren’t usually effective enough to be prescribed for mononucleosis.

Corticosteroids, a type of steroids, aren’t very effective at treating mono. Although they may alleviate some symptoms, they’re usually reserved for airway obstruction caused by swollen tonsils or lymph nodes. Patients with severe thrombocytopenia (low platelet levels) may also receive corticosteroids.

Avoid taking aspirin, as it may cause the onset of Reye’s Syndrome. Reye’s can cause brain and liver damage.

Instead of looking to medication to improve your issues, you can rest easy. Your spleen will usually get back to normal on its own, but it could take several weeks or more. A possible yet uncommon result is the need to remove your spleen.

In cases of an enlarged spleen caused by mono, the spleen may need additional time to heal after your mono symptoms have cleared.

Enlarged Spleens Are Easy To Detect

a woman health care professional assisting a patient with MRI

Detecting enlarged spleens is easy, even though they are asymptomatic. They should show up during routine full-body screenings and healthcare checkups.

If you have a bacterial or viral infection, such as mononucleosis, it can cause an enlarged spleen (called splenomegaly). Taking control of your health means knowing what’s going on with your body so you can make proactive decisions for your wellness.

Join Ezra today so you can begin regular screenings of your spleen and other organs—it’s affordable and easy to book. Prevention is the best medicine.