Abstract
Abstract: :
Purpose: Chl infections are the leading cause of ocular morbidity in the world, provoking trachoma and inclusion conjunctivitis (IC). Children may acquire the infection by respiratory, fecal, genital or nasal contamination. Acute ocular infection by Chl is characterized by a follicular, non-purulent conjunctivitis that occurs 2 to 20 days after exposure. In children with follicular conjunctivitis, the differential diagnosis of IC includes adenoviral and herpetic keratoconjunctivitis, toxic reactions and early stages of trachoma. Symptoms of IC include redness, slight discharges and a variable degree of foll in the inferior conjunctiva. The aim of this study was to assess the prevalence of Chl in children presenting foll in the inferior conjunctiva. Method: During the Rural Mexican Social Security (IMSS) Solidarity Program, 484 children (6-12 years; 91% Tzotzil ethnicity; 3.5% Chamulas; 3.5% Tzetzals; 2% Caucasian) were examined for visual acuity. Samples obtained from inferior conjunctival foll were fixed and stained by a buffered-Giemsa (Gie)or by a Mab-FITC with counterstain (bioMerieux), which detects 15 serotypes of Chl trachomatis and Chl psitacci. Results: Identification of perinuclear intracytoplasmic inclusions in Gie-stained samples confirmed the infection. Detection of Chl by monoclonal antibodies (Mab) showed higher sensitivity and specificity than Gie. Conclusion: 35% of children living in the «SJ de Ecatepec» area (Chiapas-Mexico) presented foll in the inferior conjunctiva. Chl was detected by Mab in 15% of the children, with foll and the lower detection capacities for Giemsa were confirmed here (6% versus 15%). Considering that in this rural population of children, at least 5% bear Chl in their inferior conjunctiva, massive informative, diagnostic and therapeutic measures need to be taken in order to limit the risks of future severe visual impairment.