The traumatic break in the epithelium allows the fungus to adhere to the corneal surface and develop into an infection. These presentations occur more commonly in farm workers and in those who suffer a corneal injury from organic material such as a tree branch. Filamentous fungal infections are much more prevalent in the southern United States and other warm climates. Other predisposing factors for fungal infections include contact lens wear and topical steroid use. The clinical manifestations of fungal ulcers caused by filamentous fungi may be difficult to distinguish from bacterial infection.
Patients often develop acute symptoms of pain, photophobia and decreased vision.
Yet, the progression of symptoms often follows a more indolent course than that of bacterial ulcers. In your slit lamp assessment, look for a dense, gray-white infiltrate and corneal ulceration. The infiltrate may display a feathery or indistinct border. There may be one or more satellite lesions either adjacent to the main infiltrate or several millimeters away. Many times the epithelium remains intact over a fungal infiltrate, resulting in a fungal corneal abscess.