This retrospective study evaluated the 20-year incidence, clinical features and outcomes of white dot syndromes in a community-based population. It found that white dot syndromes are rare and may be associated with other autoimmune diseases.
Even though this study has limitations, I believe it is very valuable in increasing our understanding of white dot syndromes.
The authors used the Rochester Epidemiology Project medical records linkage system of Olmsted County, Minn., to identify all patients with white dot syndromes from 1988 through 2008. Mean ophthalmic follow-up was 4.5 years and mean general medical follow-up was 9.1 years.
The incidence of white dot syndromes, adjusted to the age and gender distribution for the 2000 United States white population, was 0.45 per 100,000 per year. There were six cases of multiple evanescent white dot syndrome, four of acute posterior multifocal placoid pigment epitheliopathy, one of punctuate inner choroidopathy, and one of multifocal choroiditis and panuveitis syndrome.
Multiple evanescent white dot syndrome was more common in females, and acute posterior multifocal placoid pigment epitheliopathy was more common in males. Both generally carried a good visual prognosis. Fifty percent of cases with acute posterior multifocal placoid pigment epitheliopathy had a positive history of psoriasis. The only punctuate inner choroidopathy case carried that diagnosis as well.
The authors note the study’s limitations, which include its retrospective design and the fact that white dot syndromes can pose a significant diagnostic challenge, with many cases being mild or asymptomatic. Also, it is possible that some patients may have been missed because of inaccurate coding or because they sought care outside of Olmsted County. Therefore, the incidence figures most likely represent an underestimation of the true frequency of white dot syndromes.
To the authors’ knowledge, this is the first study to try to determine the incidence of white dot syndromes. They conclude that further studies with more patients and longer follow-up periods are needed in order to draw conclusions about visual prognosis, development of other ocular conditions and associated medical diseases.