The importance of fundus eye testing in rubella-induced deafness

The purpose of this study was to establish a new approach to improve detection of deafness due to rubella.

Colombian institutes for the deaf were visited by a medical team to perform in all enrolled individuals an ophthalmological examination with emphasis in fundus eye by a retina specialist. In cases where ocular alterations compatible with CRS were found, a medical interview by a clinical geneticist analyzing pre-and postnatal history and a thorough medical examination was done.

A total of 1383 deaf institutionalized individuals were evaluated in 9 Colombian cities in the period of 2005 to 2006, finding a total of 463 positive cases for salt-and-pepper retinopathy (33.5%), in which rubella could be the etiology of deafness. Medellin, Cartagena, Bucaramanga and Barranquilla were the cities with the highest percentage of Congenital rubella, corresponding to 22.8% of analyzed population. The analysis performed on cases in which reliable prenatal history was obtained in a second appointment (n=88) showed association between positive viral symptoms during pregnancy and salt-and-pepper retinopathy in 62.5% of cases, while both (retinopathy and viral symptoms) were absent in 29.5% of cases; showing a correlation in 92% of cases.

The frequency of deafness by rubella obtained by this study is significantly high compared with previous Colombian studies and with international reports. It was possible to correlate the antecedent of symptoms during pregnancy with the presence of salt-and-pepper retinopathy in this deaf population when reliable prenatal history was available, therefore eye testing with emphasis in fundus examination is a good indicator of rubella induced deafness. We propose a new approach in the search of deafness causes, based on a thorough ophthalmologic examination in all deaf people.