Adjuvant CXL may worsen vision in patients with moderate fungal keratitis

Treatment with adjuvant corneal cross-linking (CXL) does not seem to produce favourable results in patients with moderate filamentous fungal ulcers and may even lead to reduced visual acuity, a recent study has shown.

Consecutive patients presenting with moderate vision loss from a smear-positive fungal ulcer at Aravind Eye Hospital in Madurai, India, were included in this outcome-masked, two-by-two factorial design, randomized controlled trial.

Study eyes were randomly assigned to one of four treatment combinations using an adaptive randomization protocol. Treatment arms were as follows: topical natamycin 5% alone, topical natamycin 5% plus CXL, topical amphotericin B 0.15% alone, and topical amphotericin 0.15% plus CXL.

Patients who received CXL, irrespective of medication (topical natamycin or amphotericin), showed 1.32-fold higher odds of 24-hour culture positivity, albeit statistically nonsignificant (95 percent confidence interval [CI], 0.57–3.06; p=0.51). There was also no difference found in 24-hour culture positivity between patients on amphotericin and those on natamycin when evaluating as a group regardless of whether they received CXL or not (coefficient, 1.10, 95 percent CI, 0.47–2.54; p=0.84).

Among patients receiving CXL regardless of medication, the best spectacle-corrected visual acuity (BSCVA) was approximately 0.22 logMAR (2.2 Snellen lines) worse on average at 3 weeks and 0.32 logMAR (3.2 Snellen lines) worse at 3 months after controlling for baseline visual acuity (95 percent CI, 0.03–0.54; p=0.02).

When comparing CXL with no CXL or the two topical medications, no difference was observed in infiltrate or scar size, percentage of epithelialized or adverse events.