Correlation between clinical diagnosis and PCR analysis of serum, aqueous, and vitreous samples in patients with inflammatory eye disease

Abstract

To study the applicability (sensitivity, specificity) of polymerase chain reaction (PCR) tests in the detection of cytomegalovirus (CMV), herpes virus (HSV) and varicella zoster (VZV), Epstein-Barr virus (EBV), Mycobacterium sp and Toxoplasma gondii in the diagnosis of patients with or without AIDS, with presumably infectious uveitis, using serum, aqueous humor and vitreous humor samples. Twenty individuals with uveitis of presumed infectious origin were evaluated. Sixteen of them had AIDS, four were immunocompetent individuals. We also evaluated 4 normal controls who underwent vitrectomy surgery. Clinical evaluation of the patients was performed together by three clinicians. PCR evaluations of the serum, aqueous, and vitreous humor were performed in a masked fashion by the laboratory staff. Twelve patients had a clinical diagnosis of CMV retinitis. Of these 6 (50%) had a positive PCR for CMV in the vitreous, three (25%) had a positive PCR for CMV in the serum, and none were positive in the aqueous. Five patients had a clinical diagnosis of acute retinal necrosis (ARN). Three (60%) of these had positive PCR for HSV/VZV in the vitreous. One of these patients had a positive PCR reaction for both EBV and HSV/VZV in the vitreous samples. One patient with cutaneous herpes zoster had a positive PCR reaction for HSV/VZV in the serum. Four patients had a presumed diagnosis of ocular toxoplasmosis, one patient (25%) had a positive PCR for Toxoplasma gondii in the serum, 3 (75%) had positive results in the aqueous, and 2 (50%) had positive results in the vitreous. One patient with presumed ocular tuberculosis had a positive PCR reaction both in the serum and in the vitreous samples. Finally, none of the four control individuals revealed any positive PCR reaction. PCR is an auxiliary diagnostic procedure that should be evaluated together with ophthalmological aspects of the patient.