Ulcerative colitis (UC) is an autoimmune condition that affects the large intestine. Individuals with UC may develop high platelet counts and thrombocytosis.

Researchers estimate that up to 900,000 people in the United States live with UC. This inflammatory bowel disease causes ulcers in the colon and rectum. Symptoms range from anemia to weight loss and joint pain.

Individuals with UC may experience high platelet counts. High numbers of these blood cells can worsen inflammation and lead to secondary conditions such as thrombocytosis.

This article will examine why UC can cause a high platelet count. Read on to learn more about how this happens, available treatments, and more.

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Ulcerative colitis involves the activation of both immune and non-immune cells. Platelets are one type of cell that UC may activate. After activation, these blood cells can trigger or worsen UC inflammation. Ongoing inflammation may ultimately lead to tissue damage.

Adults typically have between 150,000 and 450,000 platelets per microliter of blood. Researchers have found that people with UC typically have higher platelet counts than people without this condition.

What is the normal platelet count range based on age?


The medical term for elevated platelets is thrombocytosis. People with this condition are at a higher risk for blood clots that may block blood circulation through the body. Symptoms of thrombocytosis may include:

  • migraine
  • weakness
  • chest pain
  • confusion
  • speech disturbances

Individuals with UC may have a higher risk of developing thrombocytosis. High platelet counts can also worsen symptoms of UC. People with this condition should speak with a doctor if they develop new or worsening symptoms.

Ulcerative colitis causes inflammation that affects the intestinal lining. Certain platelets in the body travel through the wall of the intestine. Inflammation in this wall can activate platelets as they pass through.

These activated platelets cause additional inflammation in certain other cells. This can lead to thrombocytosis. It can also cause or worsen damage to the lining of the intestine.

Higher platelet counts may be a sign of more advanced UC. In a 2020 study, researchers tested platelet levels among people with this condition. They found higher baseline platelet counts were more common among people who experienced a UC relapse.

Platelet tests can determine the number of platelets in the blood. These tests can take place in hospitals or outpatient settings.

During a platelet test, a healthcare professional first collects a blood sample.

The blood sample then goes to a laboratory for testing. Once the laboratory has processed the blood sample, a healthcare professional calls the individual to talk about the results.

Individuals may need to discontinue certain medications before getting a platelet test. Anyone preparing for this test should speak with a healthcare professional to learn more.

Individuals with UC may experience a range of different symptoms. Some frequently reported symptoms of UC include:

  • diarrhea
  • constantly feeling the need to have a bowel movement
  • bloody stool
  • rectal bleeding
  • abdominal pain or cramping

Unlike UC, thrombocytosis does not cause any symptoms in most cases. This can make it difficult to detect without a platelet test. However, certain people have a higher risk of developing thrombocytosis. Risk factors for this condition may include:

  • iron deficiency
  • a history of surgery
  • certain medications
  • a history of bleeding
  • smoking tobacco

A recent casestudy examined a 30-year-old person with UC and thrombocytosis. Before receiving a diagnosis, this individual presented with a number of worsening symptoms. These included diarrhea, vomiting, nausea, and recurrent fever.

After a full examination, this person received a platelet test. The results indicated high platelet levels, which confirmed the thrombocytosis diagnosis.

Each individual with thrombocytosis and UC may experience different symptoms. Anyone concerned about their risk for these conditions should visit a healthcare professional for an evaluation.

There are many options for lowering platelet counts in people with UC. Certain medications can help restore a healthy platelet count. These may include:

  • anagrelide
  • hydroxyurea
  • aspirin
  • interferon alfa

Another option for lowering platelet count is plateletpheresis. This procedure involves a machine that removes platelets from the blood. Plateletpheresis is generally used in emergency situations.

Treating thrombocytosis typically involves treatment for the underlying UC. This may include certain medications to reduce inflammation. In severe cases, people with UC may also require surgery to address their symptoms.

Ulcerative colitis is an autoimmune condition that causes inflammation. Increased levels of inflammation can ultimately lead to tissue damage.

People with UC may also have high platelet counts. High platelet levels can exacerbate inflammation and worsen UC symptoms. A high platelet count may also indicate thrombocytosis. This condition can cause blood clots that can negatively affect blood flow.

Anyone experiencing new or worsening UC symptoms should visit a healthcare professional. After a platelet test, a doctor can recommend treatment options to help manage UC with a high platelet count.