The efficacy of hourly prophylactic steroids in diffuse lamellar keratitis epidemic

To investigate the inciting agent, clinical features, and the efficacy of hourly steroids in the prophylaxis in a diffuse lamellar keratitis (DLK) epidemic.

One hundred and five eyes of 58 patients that had DLK after LASIK were included in the study. To identify the cause of the epidemic, some interventions were made: irrigation solution was changed from BSS to Ringer lactate (week 5), wiping of the interface with a sponge was discontinued (week 6), the air conditioner in the LASIK room was checked (week 6), the routine postoperative topical regimen was changed from fluoromethalone and fluoroquinolones 4 times a day to hourly prednisolone acetate or dexamethasone sodium and fluoroquinolones (week 7), and the trademark of the drape used was changed (week 12).

There was no statistical difference in any of the attack rates associated with variables including BSS versus Ringer lactate (9.9 vs. 14%, p = 0.4), and air conditioner check with wiping versus not wiping the interface with the microsurgical sponge (14.0 vs. 18.2%, p = 0.6). There was a significant decrease in the attack rate from 18.2 to 5.3% with use of the hourly prophylactic topical steroids (p = 0.012). After introduction of a new trademark of the drape, the incidence of DLK was further reduced from 5.3 to 0.7% (p = 0.016).

The cause in a particular DLK epidemic should be identified and eliminated adopting a scientific approach. Hourly steroid use for prophylaxis is recommended until the etiologic agent responsible has been identified.