This disease is rare in the U.S. It’s more commonly seen in developing countries, where people are more likely to have nutrient deficiencies. Vitamin A deficiency remains a public health concern in more than half of all countries, mostly affecting young children in impoverished regions.
Children 3 to 6 years of age are at a higher risk of developing night blindness due to xerophthalmia. It affects around a third of the pediatric population worldwide and causes blindness in 250,000–500,000 children in developing countries each year.
Xerophthalmia is caused by a lack of vitamin A. Human body doesn’t produce vitamin A on its own. Instead, human body have to get vitamin A from the foods they eat. Lack of vitamin A in the diet may be caused by malnutrition, malabsorption, chronic alcoholism or by highly selective dieting.
Vitamin A is a fat-soluble vitamin that humans derive primarily from diet. It has several essential functions in the body, including cell development, metabolism, immune function, vision, and reproductive function.
Vitamin A is essential for vision because it’s an element of the protein that absorbs light in the receptors in retina. Vitamin A deficiency causes metaplasia and keratinization of mucus-secreting epithelium, which can cause conjunctival and corneal xerosis, corneal ulcers, keratomalacia, and corneal scarring.
The typical symptoms of xerophthalmia include:
*Thin lining of eyelid and eyeball, called the conjunctiva, dries out, thickens, and begins to wrinkle
*Night blindness, an eye disease in which patient can’t see in dim light
*Ulcers or scars on cornea
*Bitot’s spots, or white spots on conjunctiva
*Softening of cornea
The most common animal sources for vitamin A are cod liver oil, liver, butter, cheese, eggs, and fish, whereas the most common vegetable sources include sweet potato, carrot, broccoli, sweet red pepper, spinach, and lettuce.
Xerophthalmia – Causes and symptoms
