Prevalence of eye signs in congenital rubella syndrome in South India: a role for population screening

Abstract

Purpose: Congenital rubella syndrome (CRS) resulting from maternal rubella infection, especially in the first trimester, affects an estimated 100 000 infants each year worldwide. Immunisation has reduced its occurrence in the developed world, though it remains a problem in countries with poor immunisation coverage. This population-based study was aimed at screening children below 5 years of age for ocular signs suspicious of CRS. Methods: Suspected CRS cases were recruited from hospital and outreach services of the Aravind Eye Care System over a 24-month period. Clinical confirmation was based on the fulfilment of the World Health Organization (WHO) definition, and laboratory confirmation was based on a positive test for IgM antibody. Results: Children under 5 years of age (n=51 548) with ocular complaints were screened for eye signs suspicious of CRS; CRS compatible signs were detected in 1.92% (1090) children. Of these suspects (299), 27.42% were subsequently confirmed clinically according to WHO definition, and (46) 4.2% were serologically (Laboratory) confirmed. Of all the eye signs evaluated for screening, cataracts were the most sensitive (80.43%). Conclusions: Cataracts among children have a high sensitivity for detecting CRS in India. It is the only clinical eye finding that has a high enough sensitivity and specificity to be useful as a screening tool for CRS.