[Trachoma and the conjunctival impression test].

Abstract

The Transferred Conjunctival Impression test (test d'Impression Conjonctivale Transférée) is a simple, sensitive and non-invasive method enabling populations at risk from Xerophthalmia to be identified. Nevertheless, the results of the test do seem to be influenced by the conjunctival pathology, trachomatous in particular. It appears that conjunctival deficit is noticeably more frequent in trachomatous than non-trachomatous subjects. The trial, involving a random sample of 450, four- to six-year-old children living in the Sahelian zone, enabled us to confirm and quantify this relation. In terms of relative risk, with age, place of residence and nutritional state all being equal, the rate of abnormal TCI tests was 1.7 times higher in trachomatous than non-trachomatous children. Using the Transferred Conjunctival Impression test is thus especially indicated in zones with a low prevalence of trachoma. When high, an eye examination must be carried out during the trial in order to present the results in two categories: trachomatous and non-trachomatous. Failing this, estimates may be obtained using the formulae put forward by the authors.