Risk Factors for Vitamin A Deficiency

Vitamin A deficiency is more common among poor families in developing countries, and along with poverty are many associated risk factors such as low maternal and paternal education, lack of land, crowding, poor hygiene, increased infectious disease morbidity, geographic isolation, lack of a home garden, and inadequate intake of vitamin A. Infants, preschool, and primary school-aged children are at higher risk for vitamin A deficiency, Fig. 17. Risk factors for vitamin A deficiency. Fig. 17....

Early Perspectives on Xerophthalmia

Night blindness, a clinical manifestation of vitamin A deficiency, has been known from antiquity. In the Hippocratic writings, Epidemics VI, night blindness was described among children with whooping cough (4). In the first century ad, Celsus noted the ingestion of animal liver (a rich source of vitamin A) as a treatment for night blindness in De Medicina (5). During the European era of exploration and colonization, night blindness was found to be indigenous among populations in Africa (6,7),...

Assessment of Vitamin A Status

A wide variety of methods are available to assess vitamin A status, and the more commonly utilized techniques include serum retinol concentrations, breast milk retinol concentrations, conjunctival impression cytology, dark adaptometry, RDR test, and modified relative dose response (MRDR) test (973,974). Liver retinol concentrations are often considered the gold standard for vitamin A status, but liver biopsy is highly invasive and rarely used s. The methods for the assessment of vitamin A...

Ellisons Landmark Trial and Other Therapeutic Trials of Vitamin A the Anti Infective Vitamin

Vitamin A became known as the anti-infective vitamin, and from 1920 through 1940, this vitamin underwent considerable evaluation in at least 30 therapeutic trials, from dental caries to pneumonia to measles. These studies were conducted during a period when there was an increased awareness of the problem of infant and child mortality in Europe Fig. 2. Frequency distribution of 72 children admitted to the Rigshospital, Copenhagen for xerophthalmia from 1912 to 1919. (Reprinted from ref. 48.)...

Dietary Sources and Metabolism of Vitamin A Food Sources of Vitamin A

Night Blindness Among Children

Vitamin A is available in dietary sources as either preformed vitamin A or as provitamin A carotenoids. Rich dietary sources of preformed vitamin A include egg yolk, liver, butter, cheese, whole milk, and cod-liver oil. In animal foods, vitamin A is mostly in the form of retinyl esters, such as retinyl palmitate. In many developing countries, the consumption of foods containing preformed vitamin A is limited, and provitamin A carotenoids often comprise the major dietary source of vitamin A...

Global Distribution

The prevalence of vitamin A deficiency is higher in developing countries in southeast Asia, south Asia, east Asia and the Pacific region, sub-Saharan Africa, the Middle East, northern Africa, and Central and South America (Fig. 15) (600,601). Vitamin A deficiency is considered a public health problem in about 78 countries worldwide, and the geographical distribution of vitamin A deficiency follows the same general pattern as for poverty, malnutrition, and greater burden of infectious diseases...

Prevalence and Incidence

Worldwide, there are an estimated 140 million preschool children and 7.2 million pregnant women who have vitamin A deficiency 597 . In low-income countries worldwide, there are an estimated 453,000 children with blindness or severe visual impairment, and 200,000 have corneal scarring attributed mostly to measles and vitamin A deficiency 2 . There is a close synergism between measles and vitamin A deficiency that can result in blindness, and of an estimated 30 million children who develop...

Age

Infants, preschool children, and women of childbearing age are at the highest risk of vitamin A deficiency. Risk factors for vitamin A deficiency among women are discussed separated in sections 3.1.13. and 3.1.14. The reported age distribution of xerophthalmia among infants and children varies, depending on whether the study population is community-based or based on case reports from hospitals or clinics. In general, community-based surveys suggest that the peak age for xerophthalmia among...

Vitamin A Deficiency Infection and Mortality in Developing Countries A Recurring Theme

With improvements in nutrition, hygiene, and living standards, vitamin A deficiency gradually disappeared from Europe and the United States. The Joint Food and Agricultural Organization FAO WHO Expert Committee on Nutrition focused on vitamin A deficiency as a public health problem in developing countries in the 1950s. The FAO WHO Expert Committee on Nutrition recognized that dried skimmed milk production had increased greatly after World War II, and that it was a surplus food being considered...

Vitamin A Deficiency and Increased Mortality in Children Lessons From Denmark

Denmark Nutrition

From 1909 to 1920, the Danish ophthalmologist Olaf Blegvad 1888-1961 documented cases of xerophthalmia, or clinical vitamin A deficiency, among children in Denmark 48 . From 1911 to 1917, there was a strong, gradual increase in the number of cases of keratomalacia, the most severe eye lesion of vitamin A deficiency, followed by a decline in 1918 and 1919 and then an increase in 1920. During the same period in neighboring Sweden, there was no epidemic of xerophthalmia. Blegvad showed that the...

Xerophthalmia and Keratomalacia

What Does Plasminogen

The WHO classification of xerophthalmia is shown in Table 3. This classification was first adopted in 1976 126 , with minor modification in 1982 247 . The ocular signs are Fig. 5. Night blindness in a public health poster from Indonesia. Fig. 5. Night blindness in a public health poster from Indonesia. classified in order of severity from night blindness XN to corneal ulceration and kera-tomalacia that involves one-third of the cornea or greater X3B . A corneal scar XS is not a sign of active...