Hunter syndrome in Infant/Neonate
There is a broad phenotypic spectrum of severity. The severe form is most common, with symptom onset typically between 2 and 4 years of age. Signs and symptoms include distinct, coarse facial features, intellectual disability, developmental delay, hepatosplenomegaly, skeletal deformities, joint stiffness, carpal tunnel syndrome, vision changes, recurrent ear infections, and progressive hearing loss. Hydrocephalus or spinal cord compression may develop. Patients typically develop valvular heart disease and obstructive airway disease.
Average life expectancy is about 10-15 years. The attenuated form of Hunter syndrome may have minimal neurologic symptoms, and these patients often have normal intelligence.
E76.1 – Mucopolysaccharidosis, type II
70737009 – Mucopolysaccharidosis type II
Differential Diagnosis & Pitfalls
- MPS I or MPS VII – As with Hunter syndrome, these patients excrete dermatan sulfate and heparan sulfate in their urine. See Hurler syndrome (MPS I-H).
- MPS III-VI – Urinary GAG composition can help distinguish these from Hunter syndrome. See Maroteaux-Lamy syndrome (MPS VI).
- Multiple sulfatase deficiency
- Mucolipidosis type II
- Mucolipidosis type III