A rare hematologic disease characterized by eosinophilia without evidence of clonality persisting for at least six months for which no underlying cause can be identified. The condition is associated with signs of organ damage and dysfunction. Clinical manifestations are highly variable depending on the organ systems involved and include rapidly developing life-threatening cardiovascular or neurological complications.
Data from Orphanet are used to provide information on a disease's name, synonym(s), and overview. Reference: Access aggregated data from Orphanet at Orphadata. Orphadata: Free access data from Orphanet. © INSERM 1999. Available on http://www.orphadata.org. Data version April 2026
Newly diagnosed with
Idiopathic hypereosinophilic syndrome?
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Advocacy Organizations
American Partnership For Eosinophilic Disease
APFED is dedicated to preventing and curing eosinophil-associated diseases while enhancing the quality of life for patients and families. We achieve this by passionately embracing, supporting, and advancing education, awareness, research, advocacy, and support initiatives for those affected.
Children’s Cardiomyopathy Foundation
CCF's mission is to accelerate the search for causes and cures for pediatric cardiomyopathy through increased research, education, awareness, advocacy, and support to affected children and their families.
Heart of a Giant Foundation
The mission of the HGF is to achieve better health outcomes for heart diseases and related chronic health conditions in our communities and enhance the quality of life through health education, care support, and connection to community resources.
HeartCharged
Ending preventable deaths from undiagnosed heart conditions and sudden cardiac arrest, especially in young people, and providing patient-to-patient support.
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Clinical Trials
For a list of clinical trials in this disease area, please click here.