[Application of polymerase chain reaction method (PCR) in diagnosis of endophthalmitis]

The goal of this study is to determine the usefulness of the PCR method in the diagnosis of endophthalmitis.

30 clinical specimens 18 AH and 12 VF were obtained from 20 eyes with the clinical diagnosis of endophthalmitis. These included: 14 cases after cataract surgery, 1 case post trabeculectomy, 2 cases after penetrating traumas, and 3 cases after endogenous endophthalmitis. The same samples were analysed using 2 different methods: 1. conventional microbiological techniques (microscopy and diagnostic culture) and 2. PCR directed at 16S rDNA using universal primers.

In the aqueous humor the causative pathogen was identified in one case (5.2%) by using diagnostic culture compared with seven cases (39%) by using PCR methods. In the vitreous samples the pathogen was identified in one case (9%) by using conventional method compared with five cases (50%) by using PCR. Microscopic preparation was difficult to evaluate in all samples.

PCR performed on aqueous humor and vitreous fluid is a reliable tool for diagnosis of causative organism particularly in smear and culture negative specimens. By using universal primers we are able to detect the presence of pathogen in case of endophthalmitis and than potentially by using DNA probe hybridization to determine the species of the bacteria. The discrimination between infection or non-infection endophthalmitis plays the main role in a succesful therapy.