Surgically Induced Necrotising Scleritis after Pterygium Excision

Abstract

Background: Surgically induced necrotising scleritis (SINS) presents as a focal area of intense scleral inflammation next to the site of previous scleral or limbal excision. There may be or no associated connective tissue disease. It may also follow Pterygium excision with use of antimetabolites.
Objective: To report an uncommon complication following pterygium excision, one of the commonest surgeries performed by Ophthalmologists.
Case Report: Our patient was a 62-year-old retired teacher who had a left eye nasal primary pterygium excised with Mitomycin C (MMC) dab topically. He presented 20 months later with signs and symptoms of SINS in the left eye. Systemic and laboratory examinations were normal. The scleral defect was covered with mucous membrane graft (MMG) obtained from the lower lip. The choice of MMG was due to nonavailability of amniotic membrane graft (AMG) in our centre. The patient was also placed on pulsed injection of methylprednisolone 1000mg daily in slow intravenous (IV) infusion for three days, IV cyclophosphamide 500mg on the 4th day and then on a monthly basis for six months; the graft remained intact thereafter with no further signs of inflammation over a period of six months of follow up.
Conclusion: SINS should be recognised as a possible complication of pterygium excision. The use of MMG as an alternative for sclera patch graft in the absence of AMG is suggested.

Keywords: Pterygium, Necrotising scleritis, Mucous membrane, Immunosuppressive, Antimetabolite.