Determinants of pterygium occurrence and recurrence in a rural African population

[摘要] Pterygium, a wing-shaped fibrovascular growth of the conjunctiva onto the cornea, canimpair vision and be cosmetically unacceptable. Its frequency varies in Africa and postsurgicalrecurrence in blacks may be high. Determinants of pterygium occurrence andrecurrence in rural Africans are not known. This study aimed to establish the determinantsof pterygium occurrence and recurrence in rural blacks.The case controlled study comprised 230 patients and 157 controls. Interviews and eyeexamination were conducted; however, data from 150 patients and 150 controls wereanalyzed as pre-calculated. Families of 51 cases and 50 controls were studied. Surgery wasdone on 200 eligible patients. Those who experienced post-surgical recurrence were subclassifiedas cases and those who did not, controls. Immunohistochemistry was done on 59pterygium sections and 7 controls.Family history of pterygium was present in 46 cases (30.6%) of 150, and 15 controls(10%) of 150; Odds ratio (OR) =3.93; p <0.01. Traditional eye medication was used by 79cases (52.6%) of 150, and 60 controls (40%) of 150; OR =2.03; p <0.01. The tear film wasunstable in 10 cases (6.6%) of 150, and 26 controls (17.3%) of 150; OR =0.30; p <0.01.Groups of 3-5 individuals per household were pterygium-affected in 36 pterygium families(70.5%) of 51 vs. 1 control (2%) of 50. After surgery, only 190 patients completed followupfor a minimum duration of 6 months, and 52 (27.4%) experienced post-surgicalrecurrence. Of the 52 cases, 21 (40%) had grade 2 pterygia v. 8 post-surgical controlshaving grade 2 pterygia (6%) of 138; OR =9.1; p <0.01. The limbal basal epitheliumexpressed p53 in 11 pterygia (18.6%) of 59 v. 5 controls (71.4%) of 7; p <0.01. Itexpressed matrixmetalloproteinase-1 (MMP1) in 14 pterygia (23.7%) of 59 v. 5 controls(71.4%) of 7; p =0.02. MMP2 and MMP3 were detected in 16 cases (27.1%) of 59 v. 5controls (71.4%) of 7; p =0.03.Pterygium occurred in families and was associated with traditional eye medication.Pterygium occurrence was not associated with unstable tear film, p53, and MMPs. Postsurgicalrecurrence was connected to grade 2 pterygia.

[发布机构] University of the Witwatersrand