Fungal Keratitis Resolution Influenced by 3 Prognostic Indicators

Larger corneal infiltrate size, posterior stromal involvement, and hypopyon presence are poor prognostic indicators for resolution in patients with fungal keratitis, according to research published in Cornea. 

Researchers retrospectively reviewed data from 79 eyes of 79 patients with Curvularia (70.8%), Scedosporium (18.9%), and Alternaria (10.1%) keratitis, who presented to a single center between June 2017 and July 2019. The team performed slit lamp evaluations and corneal scrapings on all participants. They administered hourly natamycin 5% either alone (n=29) or in combination with oral ketoconazole (200 mg) twice per day in cases of keratitis that involved more than the anterior one third of the stroma (n=36). Topical voriconazole 1% was added at the physician’s discretion (n=8).

Investigators determined that clinical resolution was achieved in 46 (82.1%) patients with Curvularia keratitis, 8 (53.3%) patients with Scedosporium, and 7 (87.5%) patients with Alternaria keratitis. The median duration for resolution was 27, 30 and 64 days for each group, respectively. 

A comparison between Curvularia and Scedosporium species revealed that, macroscopic pigmentation of anterior stromal plaque-like infiltrate was more common in Curvularia cases, while a larger diameter infiltrate (P =.002), posterior stromal infiltrate (P =.03), and hypopyon (P =.009), were more common with Scedosporium keratitis. 

The team also determined that maximum dimension of the infiltrate (OR=0.52; 95% CI, 0.31–0.86; P =.01) and the presence of a hypopyon (OR=0.12, 95% CI, 0.02–0.71; P =.02)) were significant factors that did not favor medical resolution. 

“[M]icroscopic and macroscopic pigmentation of plaque are clinically more common in cases with Curvularia keratitis, which is the most common type of dematiaceous fungus causing keratitis,” according to the researchers. “The presence of a plaque is seen more commonly in cases that resolve medically. The presence of a hypopyon with larger infiltrates and posterior stromal involvement are indicative of an underlying Scedosporium infection. Also, posterior stromal involvement, larger size of the infiltrate, and presence of a hypopyon are predictors of poorer prognosis.”

 Study limitations include a small sample size and retrospective nature.

Reference

Chaudhary S, Kate A, Bagga B, Mohamed A, Sharma S. Predictive Factors for Resolution of Dematiaceous Fungal Keratitis. Cornea. 2022;41(6):709-713. doi:10.1097/ICO.0000000000002825