CONJUNCTIVAL IMPRESSION CYTOLOGY FOR VITAMIN-A-DEFICIENCY IN THE PRESENCE OF INFECTIOUS TRACHOMA

Background/aims-Increased morbidity and mortality from a number of inf ectious diseases have been associated with vitamin A deficiency. Trach oma and vitamin A deficiency are both important causes of blindness in Nepal. The purpose of this study was to determine the association bet ween the diagnosis of vitamin A deficiency by conjunctival impression cytology and the diagnosis of infectious trachoma by the polymerase ch ain reaction (PCR) in the Lumbini zone of Nepal.Methods-70 children un der the age of 11 in a rural village in the Lumbini zone were examined for clinical evidence of active trachoma. The conjunctiva of each chi ld was tested for ocular Chlamydia trachomatis infection using PCR, an d for loss of goblet cells (a sign of subclinical vitamin A deficiency ) using conjunctival impression cytology. Results-The presence of infe ctious trachoma was associated with the loss of goblet cells on conjun ctival impression cytology (p=0.02). This relation was present and sig nificant even when adjusted for age (p=0.05) and degree of inflammatio n (p=0.02). In fact, even subclinical infection with chlamydia was ass ociated with an abnormal conjunctival impression cytology (p=0.02). Co nclusions-Children with infectious trachoma are significantly more lik ely to have an abnormal conjunctival impression cytology, even if the infection is subclinical. Thus, the diagnosis of vitamin A deficiency from conjunctival impression cytology alone should be made with some c aution in areas with endemic trachoma. Further studies will be needed to determine the cause of this association.