[Focus on interstitial keratitis]

Abstract

Interstitial keratitis is a non-ulcerative, non-suppurative, more or less vascularized inflammation of the corneal stroma. The corneal lesions result from the host response to bacterial, viral or parasitic antigens, or from an autoimmune response in the absence of active corneal infection. The natural history of the disease is divided into two phases: acute and cicatricial. This type of keratitis, while less common than ulcerative bacterial keratitis, is not an insignificant cause of visual loss. It is associated with systemic or infectious disease. It thus requires prompt diagnosis and etiological work-up, as well as appropriate treatment to maximize visual prognosis and avoid other complications. The main causes are bacterial infections (syphilis), viruses (40% of cases), and idiopathic (33%).