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.
Overview of Micronutrient. Deficiencies. â¢ Common when dependent on relief food or even stable. conditions. â¢ Preventable, BUT. âFood sources not common and are expensive. âFortification and supplementation. â¢ Difficult to recognize. âSymptomatic cases often represent tip of iceberg. âLaboratory assessment difficult & expensive. â¢ Lack of 1 micronutrient typically associated with deficiencies. of other micronutrients.