Waardenburg syndrome (WS) is named after the Dutch ophthalmologist Petrus Johannes Waardenburg, who, in 1947, first described a patient with hearing loss, dystopia canthorum (ie, lateral displacement of the inner canthi of the eyes), and retinal pigmentary differences.
Vitamin A Deficiency-Related Disorders (VADD). The most damaging micronutrient deficiencies in the world are the consequence of low dietary intake of iron, vitamin A, iodine and zinc.Vitamin A deficiency (VAD) is prevalent among the poor whose diets are based mainly on rice or other carbohydrate-rich, micronutrient-poor calory sources.itamin A Deficiency-Related Disorders (VADD). The most damaging micronutrient deficiencies in the world are the consequence of low dietary intake of iron, vitamin A, iodine and zinc.
Vitamin A Pediatric Dosage. Infants up to 6 months need 400 micrograms of vitamin A per day, while infants between ages 7 months and 12 months require 500 micrograms per day. For children aged 1 to 2 years, the recommended daily allowance, or RDA, for vitamin A is 300 micrograms.Children from the ages of 4 to 8 should consume 400 micrograms each day, whereas children from 9 to 13 need 600 micrograms daily.or children aged 1 to 2 years, the recommended daily allowance, or RDA, for vitamin A is 300 micrograms. Children from the ages of 4 to 8 should consume 400 micrograms each day, whereas children from 9 to 13 need 600 micrograms daily.