This work presents a review of investigations carried out in Brazil in the last 40 years, concerning the diagnosis of hypovitaminosis A. Vitamin A deficiency has been established by means of dietary intake, clinical signs, low serum and hepatic retinol concentrations, and by the rose bengal staining test and rapid dark-adaptation test. The vitamin deficiency has been found in many Brazilian, in many states capitals, in big and small cities and also in rural areas. Most of the research work has been undertaken with samples of populations of low socioeconomic level. As far as clinical signs are concerned, eye signs indicative of xerophtalmia were found mainly in the Northeastern Region. They included night blindness and conjunctival xerosis with or without Bitot's spots. More severe lesions such as irreversible changes or keratomalacia were rarely observed. Recent papers have shown the relationship between vitamin A deficiency and the increase in morbidity and mortality, mainly in pre-school children.
hypovitaminosis A; xerophtalmia; serum retinol; hepatic retinol; dietary intake; night blindness; children morbidity and mortality