Kim Stephens, DBA, Executive Director of the Muenzer MPS Research & Treatment Center, discusses a survey of clinical guidelines for mucopolysaccharidosis II (MPS 2; Hunter syndrome).
MPS II is an inherited disorder of carbohydrate metabolism that occurs almost exclusively in males. It is characterized by distinctive facial features, a large head, hydrocephalus, hepatosplenomegaly, umbilical or inguinal hernia, and hearing loss. Individuals with this condition may additionally have joint deformities and heart abnormalities involving the valves. MPS II is caused by genetic changes in the IDS gene.
The purpose of this study was to collect information on consensus statements to inform treatment guidance for MPS II, whose clinical guidelines were last updated in 2003. A Delphi survey was created, consisting of questions related to overall care and specialized care in neurology, cardiology, orthopedics, gastroenterology, pulmonology, ENT, and other relevant fields. A total of 29 practitioners participated in the survey.
Results include:
- 74% of respondents said that enzyme replacement therapy (ERT) should be started before the presentation of physical symptoms in an attenuated phenotype.
- 100% of respondents said ERT should be started before the presentation of physical symptoms in a severe phenotype.
- In the absence of a definitive genotype, 52% responded that IV ERT should be started before the onset of physical symptoms.
- 23% responded that drug antibodies in a patient with MPS II receiving IV ERT should be tested every year.
- 84% responded that HSCT should be considered for patients with MPS II who are predicted to be severe.
- 48% said that neuromonitoring should be considered for MPS II anesthesia cases that last less than 2 hours, while 44% said no.
- Most respondents said that neuromonitoring should be used for all extended MPS II procedures/surgery under anesthesia over 2 hours in duration, regardless of spine involvement.
- 21% said yes, 25% said no, and the rest responded “not in my area” to whether or not tarsal tunnel release be recommended for patients who are toe walkers.
New guidelines are necessary given the rarity of the disease and lack of specialists. These results may help guide practitioners in the creation of updated guidelines for MPS II.
To learn more about MPS II and other rare metabolic disorders, visit https://checkrare.com/diseases/metabolic-disorders/
