Impression Cytology with Transfer in xerophthalmia and conjunctival diseases

During a countrywide survey, we assessed the prevalence of clinical signs of xerophthalmia and of major conjunctival diseases in a randomized sample of 2,445 subjects representative of the population of the Republic of Djibouti. On a part of this sample, conjunctival Impression Cytology with Transfer (ICT) test and a plasma retinol determination were performed. Xerophthalmia as a public health problem was displayed by clinical signs (Bitot's spots, corneal scars among preschool children), low plasma retinol levels and ICT test results: 9.3% with deficient cytology in the rural area and 12.3% in the urban one (age-standardized rates). Results of ICT were related to age (p < 0.00001). Vitamin A deficiency was prevalent not only in preschool children but also up to 15 years. Moreover, ICT results are influenced by conjunctival diseases: compared to age-matched controls, there were more abnormal cytologies among patients with trachomatous inflammation (p = 0.025), conjunctivitis (p = 0.024) or Limbal Vernal Keratoconjunctivitis (p = 0.015). Thus ICT shouldn't be performed among children with conjunctival diseases. In the region under study conjunctival diseases had high rates of prevalence: 16.4% of trachomatous scarrings in the urban area (standardized rate), 8% of conjunctivitis among rural preschool children, and 5% of Limbal Vernal Keratoconjunctivitis among children between 5 and 14 years in both areas.