G437(P) A case of congenital glaucoma in mosaic down’s syndrome (trisomy 21)

Abstract

Aims To raise awareness of congenital glaucoma in Mosaic Downs’s syndrome. To encourage use of Down’s Syndrome Medical Interest Group (DSMIG) guidelines for ophthalmic screening in Mosaic Down’s. Methods Assessment of community, medical and surgical records. Literature review of Down’s syndrome and associated eye conditions. Multi–Disciplinary Team (MDT) discussion between paediatric, genetics and ophthalmology specialities to inform future clinical practice. Results Antenatal diagnosis of Mosaic Down’s syndrome confirmed at birth by cord blood sample showing 17% (5/30) cells affected (47XX + 21). Female term birth with no manifestations of Down’s syndrome and discharged home. Neonatal review at birth by ophthalmologist was not undertaken. At 12 weeks of age child presented at a routine community review with photophobia and corneal clouding. On examination she had bilateral buphthalmos with corneal oedema. An urgent ophthalmology review was followed by use of eye drops to relieve raised intraocular pressure. Bilateral goniotomies were performed with a repeat operation later in the left eye. Currently aged 2.5 years she has normal ocular pressures controlled by topical drops and near normal quality of vision. Conclusion There is a documented association between Down’s syndrome and congenital glaucoma but we believe this to be the first report of glaucoma in Mosaic Down’s syndrome. Glaucoma is caused by reduced trabecular drainage. The damage caused by delay in treatment is irreversible. Therefore it is important to detect and treat as early as possible. This rare presentation supports the wide variable expression of mosaic Down’s syndrome from normal to severe phenotype. The severity of symptoms does not correlate with the percentage of mosaic cells. In addition the level of mosaicism in the blood does not reflect the level of mosiacism in other tissues. UK Down’s syndrome medical interest group (DSMIG) guidelines suggest neonatal review by ophthalmologist followed by monitoring of visual behaviour in infancy and comprehensive ophthalmological review by 2 years. We suggest that these guidelines should also be applicable for Mosaic Down’s syndrome follow up irrespective of percentage of cells affected.