Information for Ophthalmologists

MPS I can affect many different organ systems and patients typically see several specialists before getting a diagnosis. Because eye involvement occurs in all MPS I patients, referral to an ophthalmologist is likely. Below are presenting symptoms encountered by opthalmologists that may lead to clinical suspicion of MPS I and warrant more definitive testing.

Corneal Clouding

Corneal clouding occurs in all MPS I patients, in some cases as early as the first year of life, and can lead to significant visual disability, especially in dim light. The condition, which has a “ground-glass” appearance, is caused by storage of glycosaminoglycans (GAGs) in the clear layers of the cornea.

Corneal Clouding
Credit:  Courtesy of J.E. Wraith

Retinal Degeneration

Retinal degeneration associated with loss of peripheral vision and night-blindness may occur and can be assessed by an electroretinogram. Visual disturbances can progress to blindness from a combination of retinal pigmentary degeneration, optic nerve compression and atrophy, and cortical damage. Open-angle glaucoma is also a common complication.^[2,6] 

References

1. National MPS Society. Otitis Media: Ear Infections. Available at: http://www.mpssociety.org/content/4066/Fact_Sheets/  Accessed January 6, 2006.

2. Clarke, L.A. Clinical diagnosis of lysosomal storage diseases. In: Organelle Diseases: Clinical Features, Diagnosis, Pathogenesis and Management. Applegarth, D.A., Dimmick, J.E., and Hall, J.G. eds. London: Chapman and Hall Medical; 1997; 46.

3. Wraith, J.E., and Alani S.M. Carpal tunnel syndrome in the mucopolysaccharidoses and related disorders. Arch Dis Child. 1990; 65:962-963.

4, Haddad, F.S., Jones, D.H., Vellodi, A., Kane, N., and Pitt, M.C. (1997) Carpal tunnel syndrome in the mucopolysaccharidoses and the mucolipidoses. J Bone Joint Surg Br. 1997; 79:578.

5. Van Heest, A.E., House J., Krivit, W., and Walker, K. Surgical treatment of carpal tunnel syndrome and trigger digits in children with mucopolysaccharide storage disorders. J Hand Surg Am. 1998; 23:239-241.

6. Neufeld EF, Muenzer J. The mucopolysaccharidoses. In: Scriver CR, Beaudet AL, Sly WS, Valle D, Childs B, Kinzler KW, et al, editors. The Metabolic and Molecular Bases of Inherited Disease. Vol. III. 8th ed. New York: McGraw-Hill; 2001:3427-3452.

7. National MPS Society. Orthopedic disorders in children with MPS/ML: A Parent’s Guide. Available at: http://www.mpssociety.org/content/4066/Fact_Sheets/ Accessed January 6, 2006.

8. Myer, C.M.D. Airway obstruction in Hurler's syndrome - Radiographic features. Int J Pediatr Otorhinolaryngol. 1990;22:92-95.

9. Peters, M.E., Arya, S., Langer, L.O., Gilbert, E.F., Carlson, R., and Adkins, W. Narrow trachea in mucopolysaccharidoses. Pediatr Radiol. 1985; 15:226-227.

10. National MPS Society. Cardiac problems associated with the MPS Syndromes. Available at: http://www.mpssociety.org/content/4066/Fact_Sheets/  Accessed January 6, 2006.

11. Stone DL, Sidransky E. Hydrops fetalis: lysosomal storage disorders in extremis. Adv Pediatric. 1999;46:409-440.