Symptom Management

MPS I is rare, progressive, and often goes unrecognized

Recognizing symptoms and making an accurate early diagnosis are critical for disease management.1
As MPS I can affect multiple organ systems, diagnosis and treatment may require collaboration and communication among geneticists, neurologists, pediatricians, developmental specialists, surgeons, cardiologists, gastroenterologists, physical therapists, and primary care providers.1

Generally, the following interventions can be used to treat MPS I symptoms2,3:

    • Valve replacement surgery may be considered early in association with a general assessment of a patient’s clinical condition
    • All patients with MPS I should undergo a cardiology evaluation, including electrocardiography and echocardiography, at diagnosis and every 1 to 2 years thereafter
    • Bacterial endocarditis prophylaxis may be advised for MPS I patients with cardiac abnormalities
    • All patients with MPS I should be monitored routinely for respiratory status
    • Airway obstruction is common in MPS I and often leads to sleep apnea, particularly during the later stages of the disease. Positive airway pressure treatment and/or low-flow oxygen with appropriate precautions for patients chronically retaining CO2 may be used
    • Tonsillectomy and adenoidectomy are frequently performed to correct eustachian tube dysfunction and decrease airway obstruction. Early surgical treatment may be recommended because of the increasing risks of anesthesia with disease progression
    • Communicating hydrocephalus is common in severe MPS I and is less common in attenuated MPS I. Ventriculoperitoneal shunting may reduce CSF pressure and ameliorate symptoms such as headache or sleep behavior but may not be able to reverse clinical disease significantly.
    • Carpal tunnel syndrome develops in most patients with attenuated MPS I. Surgical decompression of the median nerve have shown benefits in patients with MPS. Intervention at an early stage of involvement, prior to severe nerve damage, may be optimal
    • Joint replacement and specific neurosurgical approaches may be required to address spinal involvement, including atlanto-occipital stabilization
    • Physical therapy plays an important role
      • Range-of-motion exercises may help in preserving joint function
    • Corrective lenses should be prescribed to correct refractive errors
    • Wearing brimmed hat or sunglasses can help patients with corneal clouding
    • Patients should have an eye exam at least yearly and be routinely tested for glaucoma by assessing intraocular pressure
    • Monitoring of retinal degeneration is also recommended
    • Corneal grafting may be helpful for some patients
      • patients with clear grafts may still have poor vision due to associated retinal and/or optic nerve disease
      • corneal clouding may develop in the transplanted cornea

MPS, mucopolysaccharidosis

References: 1. D'Aco K, Underhill L, Rangachari L, et al. Eur J Pediatr. 2012;171(6):911-919. 2. Muenzer J, Wraith JE, Clarke LA, International Consensus Panel on the Management and Treatment of Mucopolysaccharidosis I. Pediatrics. 2009;123(1):19-29. 3. Neufeld EF, Muenzer J. In: Valle DL, Antonarakis S, Ballabio A, Beaudet AL, Mitchell GA, eds. The Online Metabolic and Molecular Bases of Inherited Disease. McGraw-Hill; 2014. Accessed March 21, 2022.

MAT-US-2205117-v1.0-10/2022 Last Updated: October 2022