BACKGROUND: When the cornea is involved in an immune response, the stroma is often selectively involved and manifests acute and/or chronic changes. This is referred to as interstitial keratitis and is characterized by cellular infiltration and vascularization of the corneal stroma with minimal involvement of the corneal epithelium or endothelium. Even though congenital syphilis is classically associated with interstitial keratitis, there are other common and more prevalent causes. The disease process can be caused by direct invasion of microorganisms into the cornea or by an immune response against a foreign antigen. There are bacterial, viral, parasitic, and systemic causes of interstitial keratitis.
CASE REPORT(S). Case reposts are presented which highlight the common causes of interstitial keratitis. More importantly, the various presentations of interstitial keratitis are noted, both in the acute and chronic stages, which make the diagnosis a challenge. Corneal photographs, case histories, and laboratory results are presented to illustrate the work-up and diagnosis for interstitial keratitis. Treatment is discussed as well.
CONCLUSIONS. The non-necrotizing inflammation of the corneal stroma known as interstitial keratitis presents acutely in a variety of ways. Similarly, the chronic picture may be variable as well. Different causes have more or less vascularization, edema, and/or subsequent ghost vessels. In addition, there may be a variable degree of resultant stromal scarring and endothelial compromise. The different etiologies highlight this.