Advances in rapid laboratory diagnosis of infectious endophthalmitis

Infectious endophthalmitis is a serious ocular condition which always requires rapid medical or surgical intervention. At present this, in a number of situations, remains empirical as a consequence of problems inherent in unequivocal identification of the causative organism, should one be present. Aqueous humor smears and culture have limited value in diagnosis. Vitreous samples can often reveal the presence of microbes, but these may not necessarily be detected in all cases, principally due to suboptimal sampling or pretreatment with antimicrobials which render microbes non-culturable on routine media. Use of electron microscopy and/or immunocytochemistry offers an alternative means of identification, but these approaches have drawbacks principally associated with interpretation. Molecular methods which identify conserved sequences from common causative microbes of endophthalmitis, or which can specify whether the organism is a bacterium or a fungus may become especially important as diagnostic tools in this clinical scenario.