Search results
Results from the WOW.Com Content Network
A major cause of Bitot's spots is vitamin A deficiency (VAD). [4] Rarely, pellagra due to deficiency of vitamin B 3 (niacin) may also cause Bitot's spots. [5] They can also be caused by Colestyramine , which is a bile acid sequestrant which can reduce the absorption of fat soluble vitamins (Vitamins A, D, E, K)
Keratomalacia is an eye disorder that results from vitamin A deficiency. Vitamin A is required to maintain specialized epithelia (such as in the cornea and conjunctiva ). The precise mechanism is still not known, but vitamin A is necessary for the maintenance of the specialized epithelial surfaces of the body.
The causes are vitamin A deficiency during pregnancy, followed by low transfer of vitamin A during lactation and infant/child diets low in vitamin A or beta-carotene. [4] [5] The prevalence of pre-school age children who are blind due to vitamin A deficiency is lower than expected from incidence of new cases only because childhood vitamin A ...
Between 250,000 and 500,000 children in developing countries become blind each year owing to vitamin A deficiency. [3] Vitamin A deficiency is "the leading cause of preventable childhood blindness", according to UNICEF. [10] [22] It also increases the risk of death from common childhood conditions, such as diarrhea.
Vitamin A plays a major role in phototransduction, so this deficiency impairs vision, often presenting with nyctalopia (night blindness). [1] In more severe VAD cases, it can progress to xerophthalmia, keratomalacia, and complete blindness. [1] Vitamin A deficiency is the leading cause of preventable childhood blindness worldwide and is a major ...
Nyctalopia (/ ˌ n ɪ k t ə ˈ l oʊ p i ə /; from Ancient Greek νύκτ-(núkt-) 'night' ἀλαός (alaós) 'blind, invisible' and ὄψ (óps) 'eye'), [1] also called night-blindness, is a condition making it difficult or impossible to see in relatively low light. It is a symptom of several eye diseases.
The U.S. Preventive Services Task Force say vitamin D supplements do not reduce the risk of falls or bone fractures in healthy older adults. The draft recommendation notes vitamin D can be helpful ...
(H53.6) Nyctalopia (Night blindness) — a condition making it difficult or impossible to see in the dark (H54) Blindness — the brain does not receive optical information, through various causes (H54/B73) River blindness — blindness caused by long-term infection by a parasitic worm (rare in western societies)