An unusual presentation of microsporidial keratitis as iritis without corneal lesion: A case report

Abstract

Objective: To describe a case of microsporidial keratitis presented with iritis without corneal infiltration mimicking herpes infection.

Case presentation: A 61-year-old woman presented with acute red eye with inflammatory reaction and keratic precipitates in her right eye. There was no corneal infiltration. She was diagnosed with iritis and treated with topical steroid. The inflammation recurred and stromal infiltration developed. Herpes keratouveitis was the most suspected cause. After ten months of treatment, steroid drops and antiviral medication could not control the inflammation. The diagnostic polymerase chain reaction was done twice, and the result showed negative for herpesviruses. Corneal biopsy was performed. The result revealed the diagnosis of microsporidial stromal keratitis. Therapeutic penetrating keratoplasty was later performed. Numerous acid-fast oval bodies were demonstrated in corneal button, confirming the diagnosis.

Conclusions: Microsporidia are increasingly identified as the cause of stromal keratitis. Iritis could be the initial manifestation before stromal infiltration develops, mimicking herpes etiology. Aqeous PCR and corneal biopsy should be performed in recalcitrant cases.