SEROLOGICAL AND POLYMERASE CHAIN REACTION-BASED ANALYSIS OF AQUEOUS-HUMOR SAMPLES IN PATIENTS WITH AIDS AND NECROTIZING RETINITIS

Objective: To evaluate the measurement of intraocular antibody product ion and detection of DNA by the polymerase chain reaction (PCR) for di agnosis of the causative microorganism in patients with AIDS and necro tizing retinitis. Methods: Paired serum and aqueous humour samples obt ained from 28 patients with AIDS and necrotizing retinitis, seen betwe en January 1987 and March 1992, were analysed for intraocular antibody production against cytomegalovirus (CMV), varicella tester virus, her pes simplex virus, Epstein-Barr virus, and Toxoplasma gondii. Specific antibody titres in the inflamed eye and in the circulation were relat ed to total immunoglobulin G content in the aqueous humour and serum. In addition, PCR analysis was performed in 15 samples. Results were co mpared to the final diagnosis, which was based on the subsequent clini cal course. Results were also related to parameters describing the imm une state of the patients: CD4 count, time between diagnosis of an AID S-defining illness and retinitis, and time of survival following the d iagnosis of retinitis. Results: In 11 (39%) out of 28 patients we foun d local intraocular antibody production which correlated with the fina l diagnosis (one out of two cases with acute retinal necrosis, three o ut of five cases with toxoplasma retinitis, and eight out of 21 patien ts with CMV retinitis). In all 13 patients with CMV retinitis PCR anal ysis detected CMV DNA. In one patient with the clinical diagnosis of T oxoplasma retinitis, Toxoplasma DNA could be determined, whereas in th e same sample CMV DNA was also found. In yet another patient with Toxo plasma retinitis only CMV DNA could be detected. A relationship betwee n results of local antibody determination with either CD4 counts, or t he time interval between AIDS-defining illness and retinitis, or survi val time after diagnosis of retinitis could not be established. CD4 co unts were higher than 50 x 10(6)/l in eight out of 19 patients with CM V retinitis. No complications of paracentesis were seen. Conclusions: Detection of intraocular antibody production and PCR analysis are quic k and safe procedures and helpful tools for diagnosis of the involved pathogen in AIDS patients with a necrotizing retinitis. Negative resul ts of local antibody production, even in the presence of detectable vi ral DNA, could not be related to the parameters of a more deteriorated immune status of these patients.