Can steroid use set the stage for a later fungal infection? Researchers are now suggesting that may be the case. A publication in BMC Ophthalmology shows that patients with fungal keratitis experience more aggressive disease progression and worse outcomes if they’ve previously used topical steroids than if they hadn’t.       

The South Korea–based study looked at the records of 83 cases with proven fungal keratitis between January 2000 and December 2016. The patients were divided into two groups: prior steroids and no prior steroids. For each group, the researchers evaluated baseline epidemiology, predisposing factors, clinical characteristics, microbiological profiles and treatment outcomes. Cases with complications or that required later surgery were deemed failures.

“The reported role of steroids in fungal keratitis includes suppression of inflammation and subsequent growth promotion of the fungal genus,” the study explains. It adds, “vertically oriented hyphae are more commonly observed in the eyes of patients who used steroids. Steroid use has been associated with a decreased response to antifungal agents, and steroid treatment itself is a known risk factor for fungal infection.”

Steroids worsen these infections due to severe inflammatory side effects and the likelihood that they’ll delay epithelial regeneration. The researchers emphasized that early steroid use is contraindicated when an infection is suspected. Clinicians should be cautious when prescribing steroids for suspected cases of infectious keratitis. 

Cho C, Lee S. Clinical analysis of microbiologically proven fungal keratitis according to prior topical steroid use: a retrospective study in South Korea. BMC Ophthalmol. 2019. October 16, 2019. [Epub ahead of print].