A Case of Mucopolysaccharidosis Type 1 with Associated Papilledema Respondent to Therapy
Sarah Roblow1, Ricardo Murguia Fuentes1, Rosario Maria Riel-Romero1
1Louisiana State University School of Medicine in Shreveport
Background:
The mucopolysaccharidoses (MPS) are disorders characterized by glycosaminoglycan deposition into body tissues. A common ocular complication of MPS is optic nerve swelling. Possible mechanisms for this optic disc edema include altered cerebrospinal fluid absorption and mucopolysaccharide deposition in the ocular tissues of patients with MPS. True papilledema could be an underlying factor, but current literature is lacking in studies corroborating this finding.
Results:
A 14-year-old female with MPS type 1 (managed with once weekly laronidase infusions) was referred to child neurology clinic for optic nerve swelling. She endorsed headaches and tinnitus. Undilated fundoscopy showed blurred optic discs. Optic coherence tomography (OCT) showed anterior displacement of the optic nerve heads and thickened retinal nerve fiber layers (RNFL). MRI brain without contrast showed optic globe flattening. CSF studies showed mildly elevated opening pressures. She began a trial of 250mg acetazolamide twice daily with symptomatic improvement after one month and improvement in optic nerve appearances after three months.
Conclusions:
Optic nerve swelling in MPS disorders is common, but the pathophysiology remains unknown. True papilledema could play a role in the symptomatic presentation of optic nerve swelling and contribute to worsening visual acuity in these patients. Other potential factors for optic disc edema include deposition of glycosaminoglycans into the ganglion cells around the optic nerves and compression of the nerves due to glycosaminoglycan deposition in the surrounding tissues, causing pseudopapilledema. We discussed a 14-year-old female with MPS type 1 presenting with headaches, tinnitus, and optic disc changes on exam and OCT. Imaging showed bilateral optic globe flattening, and CSF studies showed normal to mildly increased intracranial pressures. This prompted a trial of acetazolamide therapy with symptomatic improvement, improvements in optic disc appearances, and decreased thickening of her RNFL. Given these findings, we believe true papilledema contributed to her optic nerve changes.