title: Ocular and electrophysiological findings in a patient with Sly syndrome.
abstract: Sly syndrome (Mucopolysaccharidosis Type VII) is an autosomal recessive metabolic storage disorder due to mutations in the GUSB gene encoding the enzyme beta-glucuronidase. Deficiency of this lysosomal enzyme impairs the body's ability to break down the glycosaminoglycans - dermatan, heparan and chondroitin sulphate. Coarse facial features and macrocephaly are typically seen along with bony and skeletal abnormalities, including joint contractures and short stature. Widespread involvement occurs in many other tissues including cardiopulmonary, gastrointestinal, and neurological systems. In view of the rarity of Sly syndrome the ophthalmic features have not been well described.
  
  
  
  Case report of a 16-year-old boy with Sly syndrome with serial OCT, ocular ultrasound, and electroretinogram (ERG).
  
  
  
  Corneal clouding was present but there was no evidence of glaucoma or optic neuropathy. Despite no clinical evidence of retinopathy, electrophysiology showed reduced photopic and scotopic responses, particularly involving the b-wave which appears progressive. OCT showed normal foveal architecture and normal retinal nerve fiber thickness.
  
  
  
  Corneal clouding was noted in this patient and there is no evidence of glaucoma or optic neuropathy. Although retinopathy has not been previously described in Sly syndrome, the ERG changes in this patient suggest that retinopathy may be a feature of MPS VII.
authors.affiliation: a Department of Ophthalmology , The Children's Hospital at Westmead , Sydney , New South Wales , Australia.|b Discipline of Ophthalmology, Save Sight Institute, Sydney Medical School , The University of Sydney , Sydney , New South Wales , Australia.
authors.forename: Maree
authors.initials: M
authors.lastname: Flaherty
authors.affiliation: b Discipline of Ophthalmology, Save Sight Institute, Sydney Medical School , The University of Sydney , Sydney , New South Wales , Australia.|c Orthoptic Department , The Children's Hospital at Westmead , Sydney , New South Wales , Australia.
authors.forename: Katie
authors.initials: K
authors.lastname: Geering
authors.affiliation: b Discipline of Ophthalmology, Save Sight Institute, Sydney Medical School , The University of Sydney , Sydney , New South Wales , Australia.|c Orthoptic Department , The Children's Hospital at Westmead , Sydney , New South Wales , Australia.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Crofts
authors.affiliation: a Department of Ophthalmology , The Children's Hospital at Westmead , Sydney , New South Wales , Australia.|b Discipline of Ophthalmology, Save Sight Institute, Sydney Medical School , The University of Sydney , Sydney , New South Wales , Australia.
authors.forename: John
authors.initials: J
authors.lastname: Grigg
mesh_terms: D000293:Adolescent; D003318:Corneal Opacity / Q000175:diagnosis* / Q000503:physiopathology; D004596:Electroretinography; D005966:Glucuronidase / Q000235:genetics; D006801:Humans; D008297:Male; D016538:Mucopolysaccharidosis VII / Q000175:diagnosis* / Q000503:physiopathology; D012160:Retina / Q000503:physiopathology; D041623:Tomography, Optical Coherence; D014463:Ultrasonography; D014792:Visual Acuity / Q000502:physiology
chemical_list: D005966:Glucuronidase
keywords: Corneal clouding; Sly syndrome; electrophysiology; ocular ultrasound; retinopathy