ICD-10 Code E76.1 – Mucopolysaccharidosis, type II (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code E76.1 – Mucopolysaccharidosis, type II
What it is
E76.1 identifies mucopolysaccharidosis type II, also called Hunter syndrome. It is an inherited lysosomal storage disorder that causes buildup of glycosaminoglycans and progressive multisystem disease.
Clinical signs
Clinical features vary; refer to documentation. Common findings include coarse facial features, developmental delay, skeletal changes, hepatosplenomegaly, and airway or cardiac involvement.
When to use this code
Use E76.1 when the provider documents mucopolysaccharidosis type II or Hunter syndrome as the confirmed diagnosis. You may also use it for follow-up visits, genetic counseling, or ongoing management of a known case. Check documentation if the record only mentions suspected storage disorder.
Do not use for
Do not use this code for other mucopolysaccharidoses, such as types I, III, or VI. Do not assign it when the chart only states enzyme deficiency or family history without a confirmed diagnosis.
Coding tip
Confirm the exact MPS type in the record, because similar storage disorders have different ICD-10 codes.