title: Detection of 8-hydroxydeoxyguanosine enzyme in recurrent pterygium raising a question on its role on recurrence.
abstract: OBJECTIVE
  To detect the presence of 8-hydroxydeoxyguanosine enzyme (8-OHdG) in recurrent pterygium and its role on recurrence.
  
  
  METHODS
  Ninty-two samples were collected of which 55 from primary pterygium, 12 from recurrent and 25 from normal conjunctiva. A cross sectional study was embarked to detect the presence of the 8-OHdG enzyme in primary, recurrent pterygium and the normal conjunctival tissue by immunohistochemistry test.
  
  
  RESULTS
  THE IMMUNOHISTOCHEMISTRY TEST SHOWED POSITIVE RESULTS: 35 in primary, 2 in recurrent pterygia and 4 in normal conjunctiva, respectively. Significant association between primary pterygium and 8-OHdG enzyme (63.6% of samples are positive) and no significant relation was detected with recurrent pterygium (16.7% of samples are positive).
  
  
  CONCLUSIONS
  8-OHdG enzyme is associated with primary pterygium. It is also present in normal conjunctival tissue. For the first time it is detected in recurrent pterygia. This may raise question whether 8-OHdG enzyme has a role in recurrence of pterygium.
authors.affiliation: Department of Ophthalmology, School of Medical Sciences, Universiti Sains Malaysia, 16150, Kubang Kerian, Kelantan, Malaysia.
authors.forename: Omar M S
authors.initials: OM
authors.lastname: Ismaeel
authors.forename: Hasnan
authors.initials: H
authors.lastname: Jaafar
authors.forename: Mohtar
authors.initials: M
authors.lastname: Ibrahim