Endogenous bacterial endophthalmitis: a 17-year prospective series and review of 267 reported cases

Endogenous bacterial endophthalmitis is a rare but serious condition that occurs when bacteria cross the blood-ocular barrier and multiply within the eye. We provide an overview of endogenous bacterial endophthalmitis by reviewing 267 reported cases and integrating this with our experience of an additional 19 cases. The majority of patients with endogenous bacterial endophthalmitis are initially misdiagnosed and many have an underlying disease known to predispose to infection. This condition is often previously undiagnosed. Blood cultures are the most frequent means of establishing the diagnosis. The most common Gram positive organisms are Staphylococcus aureus, group B streptococci, Streptococcus pneumoniae,and Listeria monocytogenes.The most common Gram negative organisms are Klebsiella spp., Escherichia coli, Pseudomonas aeruginosa, and Neisseria meningitidis. Gram negative organisms are responsible for the majority of cases reported from East Asian hospitals, but Gram positive organisms are more common in North America and Europe. The visual outcome is poor with most cases leading to blindness in the affected eye. Many patients have extraocular foci of infection, with an associated mortality rate of 5%. The outcome of endogenous bacterial endophthalmitis has not improved in 55 years and clinicians need to have a high level of awareness of this commonly misdiagnosed condition.