T he treatment of endophthalmitis has progressed greatly in the past 50 years, going from a completely blinding condition to a highly treatable entity, said Donald J. D Amico, MD, professor at Harvard Medical School, Boston. D Amico updated those who attended the American Academy of Ophthalmology meeting in Dallas last year about virulence factors and endophthalmitis. Other experts spoke about corticosteroids in the management of postoperative endophthalmitis and endogenous endophthalmitis. Virulence factors Virulence is the capacity of the infecting organism to damage the host and its ability to invade and spread in the tissues. Some substances are contained within the organism itself, such as the cell surface components, cytoplasm, and endotoxins.
Organisms are also capable of liberating toxic substances.
The host responses or the major inflammatory cascades produce many substances that, in addition to eradicating the organism, can also cause damage and facilitate spread in the host tissue, D Amico said. Some therapies, notably antibiotics and other drugs, can create additional factors that could cause damage. These not only kill the organism and break them into constituent parts that may be secondarily inflammatory, but they may also alter structures so that inflammation and damage are enhanced, he said. Host factors, such as diabetes, predispose a patient to infection. Surgery and nonsurgical trauma with the obliteration and alteration in tissue anatomy are also factors in endophthalmitis.