Harmonizing Perspectives on MPS II Care in Türkiye: A Delphi Study Towards Treatment Management Consensus

Area of Science:

• Rare genetic disorders
• Lysosomal storage diseases
• Clinical practice guidelines

Background:

• Mucopolysaccharidosis type II (MPS II; Hunter syndrome) is a rare X-linked lysosomal storage disorder.
• Pathogenic variants in the iduronate-2-sulfatase gene cause progressive multisystem involvement.
• International guidelines exist, but implementation challenges persist.

Purpose of the Study:

• To establish a national expert consensus in Türkiye for MPS II treatment and management.
• To align local clinical practice with international standards for MPS II care.
• To address country-specific challenges in managing MPS II.

Main Methods:

• Modified Delphi methodology with two rounds of online surveys.
• Involved 10 experienced clinicians and a six-professor scientific committee.
• Developed 72 consensus statements and 84 exploratory questions based on guidelines and local challenges.

Main Results:

• Consensus supported enzyme replacement therapy (ERT) for all MPS II types, irrespective of cognitive impairment, due to somatic benefits.
• Recommended routine evaluations (respiratory, cardiac, neurocognitive) every 6-12 months and individualized ERT continuation into adulthood.
• Agreed on individualized premedication, transition to adult care, home infusion, patient-reported outcomes, and a national registry; hematopoietic stem cell transplantation was not endorsed.

Conclusions:

• The Delphi study achieved strong expert consensus on MPS II management in Türkiye.
• Provides a practical framework to guide clinical practice and align with international recommendations.
• Informs future policy and research priorities for MPS II in Türkiye.