Risk factors for recurrence of postoperative trichiasis: implications for trachoma blindness prevention.

Background: Trachoma is the leading worldwide cause of preventable blindness. Surgery can alleviate trachomatous trichiasis (TT), the blinding sequelae of trachoma, but recurrence rates are high.

Objective: To investigate risk factors for TT recurrence.

Methods: We conducted a prospective case-control cohort study in Nepal that included patients with TT who were undergoing bilamellar tarsal-rotation surgery and control subjects who have scarring but no TT. Conjunctivae were graded for trachoma and swabbed to detect Chlamydia trachomatis by in-house and commercial (Roche Amplicor; Roche Diagnostics Corp, Indianapolis, Ind)-polymerase chain reaction. Univariate and multivariate analyses were performed for associations with chlamydiae and other risk factors.

Results: Postoperative TT recurrence rates were 11.1% (4 cases) at 6 months and 25.0% (11 cases) at 12 months while no controls developed TT. Significantly, 5 (45.5%) of 11 patients with TT recurrences at 12 months had chlamydial infection at baseline (odds ratio, 6.0; 95% confidence interval, 1.5-24.3; P =.01), 8 (72.7%) at 6 months (odds ratio, 28; 95% confidence interval, 4.3-181.0; P <.001), and 9 (81.8%) at 12 months (odds ratio, 48; 95% confidence interval, 7.5-302.6; P =.00). No controls were infected during this time. Active trachoma and the baseline number of eyelashes touching the globe were also risk factors for TT recurrence.

Main Outcome Measures: The outcome variable was TT recurrence at 6 and 12 months.

Conclusion: To our knowledge, this is the first study to demonstrate that chlamydial infection at the time of surgery and at follow-up is a significant risk factor for postoperative TT recurrence.