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Also known as: HES/Leukemia; 4q12 (CHIC2) deletion; PDGFRA-FIP1L1 gene rearrangement; FIP1-like-1/platelet-derived growth factor alpha
Formal name: FIP1L1-PDGFRA Fusion by FISH or RT-PCR

At a Glance

Why Get Tested?

To help investigate the cause of hypereosinophilia (HE), a condition with persistent increase in the number of eosinophils, a specific type of white blood cell, or hypereosinophilic syndrome (HES), which is HE with associated tissue or organ damage; to help determine if someone with HE or HES can be treated with a tyrosine kinase inhibitor (TKI) such as imatinib

When to Get Tested?

After complete blood counts (CBC) indicate that you have persistently elevated eosinophils and your health practitioner has ruled out other causes such as allergies, parasitic infection, or medication; at regular intervals when you are being treated for HE or HES with imatinib

Sample Required?

A blood sample drawn from a vein in your arm or a bone marrow sample collected using a bone marrow aspiration and/or biopsy procedure

Test Preparation Needed?