Infectious causes of posterior uveitis and panuveitis in Thailand.

PURPOSE: To determine the infectious causes of posterior uveitis (PU) and panuveitis (panU) in Thailand.

METHODS

We investigated the infectious causes of uveitis involving the posterior segment of the eye by using real-time polymerase chain reaction (PCR) for cytomegalovirus (CMV), herpes simplex virus (HSV-1, HSV-2), varicella zoster virus and Toxoplasma gondii (T. gondii) DNA in intraocular samples of 80 human immunodeficiency virus (HIV)-negative patients. Additionally, in 61 patients, we performed Goldmann-Witmer coefficient (GWC) analysis for T. gondii.

RESULTS

Twenty-four (30 %) patients with PU and/or panU had a positive PCR result. Overall, CMV was the most frequently identified organism. While CMV was the most common cause of uveitis in the patients on immunosuppressive medications for nonocular disorders, HSV was the most common cause of posterior and panuveitis in the patients not receiving such medication. In 38 PU patients, CMV was the most common detected pathogen. In 42 panU patients, CMV and HSV-2 were the most frequently identified pathogens. Out of 61 paired samples analyzed for T. gondii by GWC analysis, only 1 revealed a positive result. There was no difference in PCR results between aqueous humor and vitreous samples.

CONCLUSIONS

CMV was the most frequently identified infectious organism in posterior and panuveitis of HIV-1-negative Thai patients. Aqueous humor and vitreous samples showed similar diagnostic values in PCR analysis.