Common Blood Work Drawn In Myeloproliferative Neoplasms

If you have a myeloproliferative neoplasm, you may need to have frequent blood work. These conditions, which include polycythemia vera (PV), primary myelofibrosis (PMF), essential thrombocytopenia (ET), chronic myelogenous leukemia (CML), and atypical myeloproliferative neoplasms, involve the abnormal growth of blood cells.

In some cases, myeloproliferative disorders may lead to health complications such as bleeding, or they can develop into leukemia, a type of blood cancer.

This article will answer your questions about the most common types of blood work you will need when you have a myeloproliferative disorder.

Scoring Systems

There are several ways of assessing myeloproliferative disease severity, progression, and the effectiveness of treatment. These methods can incorporate symptoms and blood tests.

For example, PMF is often scored using the classical International Prognostic Scoring System (IPSS) and Dynamic-IPSS, which both involve criteria that include blood tests.

Complete Blood Count (CBC)

A complete blood count (CBC) is one of the most common types of lab work used to monitor blood disorders. The CBC looks at all your blood cells, which include white blood cells, red blood cells, and platelets.

This test, which may offer the first clues about what is causing your symptoms, may need to be repeated at scheduled intervals if you are undergoing treatment.

A CBC can identify changes in your condition too. For example, ET and PV can evolve into myelofibrosis or leukemia. The early signs of this change, such as a big drop in the hemoglobin and platelet count, can be detected with a CBC.

White Blood Cells (WBCs)

White blood cells (WBCs) are a part of your immune system, and they help fight infections.

There are five types of WBCs:

• Neutrophils
• Lymphocytes
• Monocytes
• Eosinophils
• Basophils

The number of WBCs in your blood is usually the first number reported on the CBC. The CBC differential (often called the diff) looks at what percentage of each type of WBC is present.

In PV or ET, your WBC count might be slightly elevated. In PMF, some people will have an elevated WBC count, some a normal count, and others a low count.

Red Blood Cells (RBC)

The body's red blood cells (RBCs) carry oxygen from the lungs to the organs.

There are a few different red blood cell measures reported on a CBC:

• The RBC count is the total number of red blood cells.
• Hemoglobin is a measure of the protein found in RBCs that carries oxygen. 
• Hematocrit represents the percentage of the blood that is made up of RBCs.

In conditions that cause the number of RBCs to rise, like PV, the hemoglobin and hematocrit numbers will be elevated. The hematocrit is often used to check on how treatment for PV is working.

Medications or phlebotomy (physical removal of blood) are adjusted based on the desired hematocrit range, which is typically less than 45% in men and less than 42% in women.

A blood transfusion may be needed when hemoglobin drops below 8 grams per deciliter. Anemia, a low level of RBCs, can have many causes—and the red blood cell values can help point to the cause.

Platelet Count

A platelet count also is part of the CBC. Platelets help your blood clot, and high or low levels can be indicators of worsening disease.

In people with ET that requires care, the platelet count serves as a treatment guide based on the desired platelet count.

Blood Smear

A blood smear is a visual assessment, using a microscope, of the size and shape of blood cells in a sample.  It can be used to determine distinguishing features of myeloproliferative disorders and other blood diseases.

For example, red blood cells and platelets become abnormally shaped in myelofibrosis. And certain types of cancer can be identified by the changed appearance of blood cells.

Von Willebrand Panel

People with ET are at risk of developing acquired von Willebrand disease, a bleeding disorder. This risk goes up as the platelet count increases (more than one million platelets per microliter). If you have ET and bleeding, a von Willebrand panel may be done to see if this is the cause. Treatment for this condition is focused on reducing the platelet count.

Summary

A complete blood count, blood smear, and von Willebrand panel are among the most common tests for people who have or may have a serious blood disorder. Depending on your specific condition, you might need other tests too. Scoring systems used to assess disease severity and status often include these blood test results.

More blood work often is needed after the initial diagnostic test because your healthcare providers will need to continue to monitor your condition to see whether your treatment is working.

A Word From Verywell

If you are having frequent blood work, you can compare your new test results with those of your previous tests to see the changes your healthcare provider is looking for. The clinician might be using certain benchmarks to determine whether you need a change in treatment. Don't hesitate to ask any questions you have about your results and what they mean for your health.