Interstitial keratitis; Non-ulcerative keratitis; Syphilitic keratitis

A nonsuppurative (nonmelting) inflammation of the corneal stroma that tends to spare the epithelium and endothelium.

Many infective, immunologic, and environmental factors could contribute to this disease. Among the most common etiologic factors are syphilis and herpes viral infections. Other causes include tuberculosis, leprosy, Lyme disease, brucellosis, leptospirosis, influenza, mumps, onchocerciasis, Acanthamoeba, leishmaniasis, measles, vaccinia/variola, sarcoidosis, contact lens keratitis, lymphoma, and exposure to gold or arsenic. An idiopathic form of this disease is called Cogan’s syndrome.

The ocular involvement could be seen unilaterally or bilaterally. Additionally, it could range from restricted to wide spread of the cornea. The occurrence of systemic symptoms could vary based on the underlying cause of the disease. Finding the etiologic factor is essential in...