Diagnostic Criteria for Idiopathic Hypereosinophilic Syndrome (HES) are:

1.      Persistent eosinophilia of over 1500/cubic millimeter for longer than 6 month;

2.      Lack of evidence of other known causes of secondary hypereosinophilia (SH);

3.      Multiple organ involvement.

Diseases Associated with Eosinophilia

"Allergic" Diseases

• Atopic and related diseases
• Medication-related eosinophilias

Infectious Diseases

• Parasitic infections, mostly with helminths
• Specific fungal infections: allergic bronchopulmonary aspergillosis, coccidioidomycosis (acute and sometimes disseminated)
• Other infections--infrequent, including HIV-1 and HTLV-1

Hematologic and Neoplastic Disorders

• Hypereosinophilic syndrome
• Leukemia
• Lymphomas, including nodular sclerosing Hodgkin's disease
• Tumor associated
• Mastocytosis

Diseases with Specific Organ Involvement

• Skin and subcutaneous diseases, including urticaria, bullous pemphigoid, eosinophilic cellulitis (Well's syndrome), episodic angioedema with eosinophilia
• Pulmonary diseases, including acute or chronic eosinophilic pneumonia, allergic bronchopulmonary aspergillosis
• Gastrointestinal diseases, including eosinophilic gastroenteritis
• Neurologic diseases (e.g., eosinophilic meningitis)
• Rheumatologic diseases, especially Churg-Strauss vasculitis; also eosinophilic fasciitis
• Cardiac diseases (e.g., endomyocardial fibrosis)
• Renal diseases, including drug-induced interstitial nephritis, eosinophilic cystitis, dialysis

Immunologic Reactions

• Specific immune deficiency diseases: hyper-IgE syndrome, Omenn's syndrome
• Transplant rejection: lung, kidney, liver

Endocrine

• Hypoadrenalism: Addison's disease, adrenal hemorrhage

Other

• Atheroembolic disease
• Irritation of serosal surfaces, including peritoneal dialysis
• Inherited