Infectious diseases of the conjunctiva and cornea

The modern local antibiotics, such as the aminoglycosides and quinolones, are very successful in treating infectious conjunctivitis and keratitis. More notably in some Third World countries, however, suppurative keratitis is found in more than half of the infectious disease cases caused by Fusarium species. Here, of course, treatment should be antifungal. The emergence of some problematic microorganisms is related to contact lens wear. Pseudomonas, for example, have the ability to adhere to contact lenses and thus form microcolonies, which are protected by biofilm that predisposes to infection. Acanthamoeba infections of the cornea are a direct consequence of inappropriate or inadequate disinfection of contact lens systems. Occasionally the diagnosis of herpes simplex manifestations of the outer eye can be very difficult. Even more confusing is the delayed appearance of zoster manifestations, such as pseudodendrites, particularly in cases of zoster sine herpete eruptione. The polymerase chain reaction is of particular value in demonstrating the presence of varicella zoster DNA. Although infectious disease of the outer eye remains common, the incidence and complications have increased because of frequent use of antimicrobial agents. In the under-developed areas of the world, however, infections are still very common, are frequently caused by fungi, and are the cause of serious ocular complications. In the Western World infectious eye disease does not seem to be a major diagnostic or therapeutic point at present. Some organisms that have been in the environment all along, however, have emerged in the past half century as a major problem. Thus, in the past years a number of new techniques in diagnosis as well as new insights in pathophysiology and new developments in treatment have emerged that are of interest.