ICD-10 Code D72.110 – Idiopathic Hypereosinophilic Syndrome [IHES] (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code D72.110 – Idiopathic hypereosinophilic syndrome [IHES]
What it is
D72.110 identifies idiopathic hypereosinophilic syndrome, a disorder marked by persistent eosinophilia without an identified cause. Use this code when documentation confirms IHES or hypereosinophilic syndrome of unknown origin.
Clinical signs
Clinical features vary; refer to documentation. Commonly, patients may have evidence of eosinophil-related organ involvement, such as skin, lung, heart, or neurologic findings, along with persistent eosinophilia after other causes are excluded.
When to use this code
Use D72.110 when the provider documents idiopathic hypereosinophilic syndrome, especially after evaluation rules out secondary causes such as allergy, infection, malignancy, or drug reaction. It may also apply when the note states HES is idiopathic or primary. Check documentation if the record only says eosinophilia without the syndrome diagnosis.
Do not use for
Do not use this code for eosinophilia with a known cause, such as parasitic disease, allergic disease, or medication reaction. Also avoid it when the chart documents only elevated eosinophils without hypereosinophilic syndrome.
Coding tip
Verify that the record supports idiopathic disease and not a secondary eosinophilia before assigning D72.110.