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How We Diagnose Juvenile Myelomonocytic Leukemia (JMML)

  • The first step in treating your child is forming an accurate and complete diagnosis. JMML is often suspected due to results from a routine blood test conducted for other reasons.

    Your child's physician may order different tests, including:

    • A complete medical history and physical exam.
    • Complete blood count (CBC): A measurement of size, number, and maturity of different blood cells in a specific volume of your child's blood.
    • Additional blood tests may include blood chemistries, evaluation of liver and kidney functions, and genetic studies.
    • Bone marrow aspiration and biopsy: Marrow may be removed under local anesthesia. In aspiration biopsy, a fluid specimen is extracted from the bone marrow. In a needle biopsy, marrow cells (not fluid) are removed. These methods are often used together.
    • Chromosomal analysis: A test to help distinguish JMML from other leukemias and allow physicians to tailor treatment to the specific disease.
    • Spinal tap/lumbar puncture: A special needle is placed into the spinal canal via your child's lower back to access the area around the spinal cord. The pressure in your child's spinal canal and brain can then be measured. A small amount of cerebral spinal fluid (CSF), the fluid that bathes your child's brain and spinal cord, is removed and tested for infection or other problems.

    After we complete all necessary tests, our experts meet to review and discuss what they have learned about your child's condition. We will meet with you and your family to discuss the results and outline the best treatment options for your child.