An Adult Case of Fulminant Mumps Keratitis With Positive Viral RNA in Aqueous Humor Detected by RT-PCR

PURPOSE:To report an adult case of mumps keratitis with mumps virus in aqueous humor and decreased corneal endothelial cell density. METHODS:Case report. RESULTS:A 60-year-old female with a 39°C fever and bilateral parotid swelling diagnosed with mumps and treated for photophobia, pain, redness, and decreased vision in 1 eye, was referred to our hospital when her condition deteriorated despite receiving betamethasone phosphate instillation and antiglaucoma agents for elevated intraocular pressure (52 mm Hg) and iritis. Her right eye was normal, whereas her left eye showed 20/400 visual acuity, 21 mm Hg intraocular pressure, ciliary injection and edema, opacity, and Descemet folds in the entire cornea. Round white keratic precipitates were present on the posterior corneal surface, whereas anterior chamber cells could not be examined in detail because of corneal edema. Mumps virus was detected by reverse transcriptase polymerase chain reaction in an aqueous humor sample taken at the time of admission. Following diagnosis of keratitis, administration of 30 mg oral prednisolone daily and frequent instillation of betamethasone phosphate steadily improved her corneal edema and opacity. In her left eye, visual acuity recovered to 20/16 and keratitis was resolved at 4 weeks; however, corneal endothelial cell density was significantly decreased to less than 400 per square millimeter. CONCLUSIONS:Mumps keratitis may cause severe corneal endothelial cell loss.