Klebsiella pneumoniaeas the Most Frequent Pathogen of Endogenous Endophthalmitis

Background/Aims: Endogenous endophthalmitis (EE) is rare. However, the visual outcome of patients with EE is very poor. Many\ncases of EE caused by Gram-negative bacterial infections have recently been reported. This study was conducted to explore the\nmost frequent pathogens, diagnosis, and treatment outcomes of EE.\nMethods: A retrospective analysis was carried out in 23 patients diagnosed with EE through clinical manifestations and ophthalmic\nexaminations in three hospitals between January 2000 and April 2011. Samples from 23 patients with EE were analyzed\nmicrobiologically.\nResults: Pathogens were identified in 18 (78%) of the 23 blood, liver aspirate, and/or vitreous humor samples. Klebsiella\npneumoniae was the most frequent organism (13/23, 57%). Abdomino-pelvic imaging (21/23, 91%) was performed to evaluate the\nprimary site of infection. The most common primary infection was liver abscess (14/23, 61%). Despite administration of\nintravenous antibiotics and intravitreal injection, only six of 23 patients showed improvements in visual acuity. Thirteen (57%)\nexperienced worse visual acuity. Four (17%) were eventually enucleated.\nConclusions: In patients diagnosed with EE, abdomino-pelvic CT is required to exclude the presence of liver abscess. If a liver\nabscess is identified, percutaneous drainage should be considered. Considering the rapid progression and poor prognosis of EE,\nearly diagnosis and immediate management are vital. We currently suggest that empiric antibiotics for treatment of EE should have\nactivity against Gram-negative bacilli such as K. pneumoniae. (Korean J Med 2012;82:200-207)\nKeywords: Endophthalmitis; Klebsiella pneumoniae