DEC 02, 2014
This retrospective study found that ganciclovir treatment was effective for clearing the viral load, assisting with IOP control and preserving the corneal endothelium of cytomegalovirus (CMV)-positive Posner-Schlossman syndrome patients.
The authors reviewed the charts of 126 Posner-Schlossman syndrome patients seen a university uveitis clinic in Taiwan between 2005 and 2013. Of these, 68 were CMV-positive and treated with 2% topical ganciclovir.
All eyes responded within a month, and aqueous humor was negative for CMV within three months. CMV-positive eyes were more likely to require glaucoma filtering surgery and had a somewhat lower corneal endothelial cell density. However, the probability of a 20% decrease in cell density over five years was the same in positive and negative patients, and during follow-up, there were the same number of “crises” (IOP >30 mmHg) in both groups.
The most interesting thing about this study may be the large number of CMV-positive Posner-Schlossman patients in Taiwan. While this disease is not limited to East Asians by any means, it has been suggested this population is at higher risk. However, the best treatment is not clear.
CMV-positive eyes can spontaneously become CMV-negative. In fact, Possner Schlossman is self-limited, at least early in the course, and so one would expect that the virus clears rapidly without treatment. Also there are at least theoretical concerns about using topical therapy. While the study’s authors use 2% ganciclovir, the commercially available solution is 0.15%. Using sub-therapeutic doses could actually increase the risk of resistance.