Do fungi cause retinopathies?

There are several retinopathies of unknown cause; among them AZOOR, Multifocal choroiditis, Serpiginous choroiditis, Idiopathic Blind Spot Enlargement Syndrome … etc.

The progressive nature of these conditions causes most patients to gradually lose their vision until many of them are left blinded. It must be considered that not only is the diagnosis most patients not easy, especially in the early stages of the disease, but that the identification of faster diagnosis methods would lead to the correct treatment sooner, avoiding in this manner the increasing loss of visual acuity.

Without a doubt, discovering the cause of each of these retinopathies would bring new hope of their treatments. Three years ago, with the help and financial support of ONCE, a research team led by Luis Carrasco professor of microbiology at the Universidad Autónoma de Madrid, noticed that a patient suffering form AZOOR was also infected by a type of yeast called Candida famata. In collaboration with the Clínica Barraquer, these studies have been extended to other patients with AZOOR or with Serpiginous choroiditis.

In January this year, information about the fungal infection in these patients was published in the Journal of Clinical Microbiology

(Pisa, D., M. Ramos, P. García, R. Escoto, R. Barraquer, S. Molina y L. Carrasco. Fungal infection in patients with Serpiginous choroiditis or acute zonal occult outer retinopathy. J. Clin. Microbiol. 46, 130-135 (2008)).

To carry out this investigation the researchers analyzed blood samples looking for antibodies against yeasts, as well as different fungal components such as proteins and DNA. These results indicate the existence of a disseminated mycosis in most of the analyzed patients which suggests that retinopathies like AZOOR and Serpiginous choroiditis are caused by fungal infections. Looking for treatments based on current anti fungal drugs could offer great benefits for these patients. The clinical studies about the effects of anti fungal compounds in the evolution of these patients will be crucial to determine whether the presence of mycosis is the cause of the loss of visual acuity.

Future investigations by Dr. Luis Carrasco's research group will lean towards the improvement of diagnosis techniques for fungal infections and the cause of other retinopathies. These techniques will also be useful for the analysis of the evolution and effectiveness of the possible anti fungal treatments that are implemented with these patients.