[Xerophthalmia: current data]

Xerophthalmia is a term covering a range of ophthalmologic manifestations due to vitamin A deficiency. This condition occurs in preschool children in tropical regions affected by protein-caloric malnutrition. Clinical manifestations of the disease have been summarized in the 1974 five-grade WHO classification. Clinical diagnosis was traditionally made using a slit lamp to detect the pathognomonic manifestations and consequences of corneal and conjunctival xerosis. Currently diagnosis is greatly facilitated by determination of plasma levels using a micromethod, especially the relative dose response (RDR) test, and by conjunctival impression cytology (CIC). CIC is a simple and reliable method which allows mass screening and thus more effective evaluation of the impact of xerophthalmia on public health in Africa. The relationship between xerophthalmia and measles is complex. Vitamin A deficiency promotes measles which can in turn hasten perforation of keratomalacia especially in undernourished children. Vitamin A has a beneficial effect on both xerophthamia and measles. Curative and prophylactic administration of vitamin A at doses recommended by the W.H.O. considerably reduces not only xerophthalmia-related morbidity but also child mortality in tropical areas.