AN IMPROVED TECHNIQUE FOR THE DIAGNOSIS OF VIRAL RETINITIS FROM SAMPLES OF AQUEOUS-HUMOR AND VITREOUS

We applied the technique of DNA amplification with the polymerase chai n reaction to nine aqueous humor and five vitreous samples from HIV-1- infected patients with clinically diagnosed cytomegalovirus retinitis. For the amplification, recently published primers specific for herpes simplex virus (HSV), varicella zoster virus (VZV) and cytomegalovirus (CMV-1), were used. Additionally, a newly developed primer pair speci fic for the main immediately early gene of CMV (CMV-2) was selected an d compared with the published one. All primers were tested on noninfec ted and HSV-, VZV- and CMV-infected human fibroblast cell culture supe rnatant, thereby excluding cross-reactivity of the chosen primers. In none of 13 aqueous humor and six vitreous samples of healthy controls was any viral DNA amplified. Using the CMV-1 primers, we detected CMV DNA in five of nine aqueous humor and three of five vitreous samples a mplifying a DNA fragment 435 base pairs in length. With the CMV-2 prim ers, we detected a CMV DNA fragment with a length of 110 base pairs in eight of nine aqueous humor and in four of five vitreous samples. Add itionally, CMV DNA was found in three of nine urine and two of nine sa liva specimens. Both CMV and HSV DNA were amplified in one aqueous sam ple. Varicella DNA was not detected in any of the specimens. Thus, the polymerase chain reaction is more sensitive than other comparable dia gnostic tests and may provide an alternative to conventional virus iso lation and in situ hybridization techniques for the laboratory diagnos is of viral ocular disease.