Predictors of outcome in fungal keratitis

Abstract

Purpose: To analyse predictors of clinical outcome in fungal keratitis.

Methods: Data was collected during a prospective, randomized, controlled, double-masked clinical trial of treatment for fungal keratitis. Clinical features at presentation and demographics were collected at the enrollment visit for all patients. Pre-specified clinical outcomes included 3-month visual acuity and infiltrate/scar size, time to re-epithelialization, and corneal perforation. A separate multivariable model with each outcome as the dependent variable included all predictor variables.

Results: Predictors for worse 3-month visual acuity include older age (P=0.024), worse presentation visual acuity (P<0.001), larger infiltrate size at presentation (P<0.001), and pigmented ulcer (P=0.030). Larger infiltrate size at presentation was a significant predictor of worse 3-month infiltrate/scar size (P<0.001). Larger epithelial defect size was a significant predictor of perforation (P=0.0013). Predictors of longer time to re-epithelialization include infiltrate size at presentation (P<0.001) and older age (P=0.025).

Conclusion: Ulcer severity at presentation is highly predictive of worse outcomes. Presentation of clinical characteristics such as baseline acuity and infiltrate scar can provide important information to clinicians about prognosis, and may help guide management and treatment decisions. Prevention of corneal ulcer remains important, as it is difficult to change the course of the ulcer once it has begun.

Figure 1

Three-month best spectacle-corrected visual acuity (BSCVA) plotted against the baseline BSCVA. Visual acuity is expressed as logMAR (‘count fingers' was expressed as 1.7 logMAR, ‘hand motion' as 1.8, and ‘light perception' as 1.9). The depth of the ulcer is expressed as the size of the plotting symbol. A triangle indicates a lesion with a feathery border; a circle no feathery border. The presence of endothelial plaque is indicated by a filled symbol. A horizontal bar indicates hypopyon. When the lesion fills the central 4 mm and extends into the periphery, the plot colour is red. The curve shows a smoothing spline (non-parametric regression) fit. Note that in the upper right of the figure, plot points are superimposed at several locations; the separate symbols for each person at each location are shown in separate breakout boxes to the top and right of the figure, with a line connecting the breakout box to the graphical location where the superimposed symbols broken out within that box appear on the plot.