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Query: KEGG:D06543 (Vitamin A)
 3,039 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

During a preliminary survey on xerophthalmia in North Sumatra, Indonesia, a total of 1754 children of 0-6 years of age were examined clinically as well as with a vital staining technique, using Rose-Bengal 1%-Fluorescein sodium 1% eyedrops. Differences in prevalence were found between children from the rural villages, from Gunung Pamela rubber estate and from one Health Centre and two kindergartens in Medan town. None of the children in the estate and in Medan had Bitot spots or acute corneal involvement; conjunctival xerosis (XIA) was found in 28% among boys and 11% among girls at the rubber estate, whereas in Medan only 1% had XIA. In the village, the calculated minimum point prevalence rates for X1B, X2 + 3 and XS were respectively 0.29%, 0.16% and 0.45% for age-group 0-6 years, sexes combined. According to WHO criteria xerophthalmia should, therefore, be considered of public health importance in the rural area visited. The potential use of the vital staining technique in early diagnosis of xerophthalmia is discussed. WHO criteria for assessment of the magnitude of the xerophthalmia problem as well as the guidelines for xerophthalmia surveys from the International Vitamin A Consultative Group have been analysed in this survey as a casestudy.
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PMID:Xerophthalmia in North Sumatra. 88 9

Xerophthalmia is a commonly encountered nutritional disorder that affects the growing population of the world. Conjunctival and corneal epithelial cells contain peroxidase enzyme. In experimentally induced Vitamin A deficiency conjunctival and corneal peroxidases are markedly lowered indicating direct or indirect relation of Vitamin A to epithelial functional integrity.
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PMID:Conjunctival and corneal peroxidases in vitamin A deficiency. 145 83

Even though the primary prevention of many eye diseases can be effectively incorporated into the existing pattern of rural eye camps, efforts in this direction are restrained and insubstantial. We describe our technique and experience in the prevention of xerophthalmia by organising a distinct entity called a xerophthalmia clinic in our eye camps. The clinic consists of an Ophthalmologist or an Ophthalmic assistant who will exclusively examine children who come to the eye camp. This is perhaps, the first report on rural xerophthalmia clinics, in ophthalmic literature. Over a seven year period from 1984 to 1990 we have conducted 71 xerophthalmia clinics amongst the ninty eye camps organised. A total of 11,370 children were examined in the xerophthalmia clinic out of which 18.9% were afflicted with the disease. Therapeutic doses of Vitamin A were administered on the spot to the afflicted and prophylactic doses were administered to the rest. Intensive health education efforts are made through clinics to effectuate change in dietry habits towards consumption of locally grown DGLV (Dark Green Leafy Vegetables) like Anthenum, chenopodium and Amaranthus. A bipronged offensive consisting of mega-dosing and health education is, for the present and the foreseeable future, the best strategy to combat xerophthalmia in this desert region. A year by year breakdown of prevalence rates in the present study shows that in years of severe drought the prevalence of xerophthalmia increases three fold over the non-drought or mild drought years, thereby demonstrating that drought is a substantial risk factor in developing countries leading to vitamin A deficiency and xerophthalmia.
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PMID:Xerophthalmia clinics in rural eye camps. 145 16

The changes in the vitamin A and nutritional status of children from a rural area in Senegal were determined by the same team during two cross-sectional surveys distant from exactly one year. At baseline (T = 0 year) 1,259 children were chosen at random. One year later (T = 1 year), 1,008 children were re-examined. Vitamin A and nutritional status were assessed by clinical and cytological methods, and by anthropometrical indicators for the 1,008 participants, respectively. No signs of xerophthalmia were recorded at T = 0 and T = 1 year. The proportions of children deficient in vitamin A as defined by abnormal cytology and suffering from stunting were similar at these two measuring points. Even though these percentages remained similar at T = 0 and T = 1 year, there existed little movement between the abnormal and normal eye cytology group and the stunted and non-stunted group. Since vitamin A is required for normal growth, we calculated the mean linear gain in height according to the eye cytological changes assessed between the two examinations. We found that mean linear growth increments were higher in the groups of children who remained abnormal or reverted to abnormal cytology than in those who remained normal or reverted to normal cytology.
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PMID:Annual assessment of the vitamin A and nutritional status of children during two cross-sectional surveys. 147 2

20-40 million children in the world have mild vitamin A deficiency and another 3 million have severe vitamin A deficiency leading to high rates of xerophthalmia and blindness. Vitamin A influences growth, survival, and resistance to infection. Vitamin A deficiency reduces the T-cells' ability to fight infection and decreases mucous production resulting in more bacteria being able to attach themselves to respiratory mucosa. Thus it increases the body's susceptibility to respiratory infection. For example, health workers in rural Indonesia who followed children for 18 months and learned that those with mild vitamin A deficiency are twice the risk of respiratory infection than those who do not have such a deficiency. This risk is higher regardless of the children's overall nutritional status. A study in urban India shows the same results. A study in Ethiopia finds children with xerophthalmia not only at increased risk of respiratory infection but also of diarrhea. Other studies demonstrate that respiratory disease, diarrhea, and measles precipitate vitamin A deficiency. For example, corneal ulceration follows an episode of measles in 79% of all corneal ulceration cases in Tanzania. In Indonesia, children with measles are 11 times more likely to have xerophthalmia. Children with mild vitamin A deficiency in Indonesia face death 4 time more often than those with no such deficiency. Vitamin A supplementation decreases mortality 72% in 60-71 month old children and 15% in 12-23 month old children, yet increases it 23% in 36-47 month old children. In Ethiopia, an infection is more predictive of severe, symptomatic vitamin A deficiency than is preexisting malnutrition. Still vitamin A deficiency increases the likelihood of respiratory infection and diarrhea. Thus vitamin A deficient children enter a downward spiral. The longterm solution to vitamin A deficiency is community development and increased consumption of dark green edible plants and red and orange fruits.
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PMID:Vitamin A. 180 40

The effect of vitamin A supplementation on preschool child morbidity and mortality was assessed in a prospective double-blind placebo-controlled study around Hyderabad, India. Every six months 200,000 IU vitamin A was given to 7691 children (treatment group) whereas 8084 children received a placebo (control group). Morbidity and mortality data were collected every three months. Risk of respiratory infection was higher in children with mild xerophthalmia than in children with normal eyes. Vitamin A supplementation had no effect on morbidity status. Mortality rates were similar in the two groups; it was highest in children who did not receive either vitamin A or placebo. The findings suggest that vitamin A supplementation alone may not reduce child mortality.
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PMID:Effect of massive dose vitamin A on morbidity and mortality in Indian children. 167 77

Vitamin A adequacy is discussed in terms of the recommended allowances appropriate for the needs of the majority of individuals. Deficiency can result in xerophthalmia and permanent blindness and in increased mortality rates among children. Toxicity has been associated with the overconsumption of vitamin A supplements. Acute hypervitaminosis A may occur after ingestion of greater than or equal to 500,000 IU (over 100 times the RDA) by adults or proportionately less by children. Symptoms are usually reversible on cessation of overdosing. Factors influencing chronic hypervitaminosis A include dosing regimen, physical form of the vitamin, general health status, dietary factors such as ethanol and protein intake, and interactions with vitamins C, D, E, and K. Both excess and deficiency of vitamin A in pregnant animals was shown to be teratogenic. In humans, congenital malformations associated with maternal over-use of high doses of vitamin A were reported but no cause-and-effect relationship has been established. Deficiency of the vitamin during pregnancy has also been associated with congenital abnormalities. Reported incidences of vitamin A toxicity are rare and have averaged fewer than 10 cases per year from 1976 to 1987.
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PMID:Safety of vitamin A. 249 45

Vitamin A deficiency is a serious problem throughout the developing world. An estimated 25-50 million children may well suffer the physiologic consequences of vitamin A deficiency; 5 million develop xerophthalmia, of whom 250,000 to 500,000 go blind every year; and untold numbers are at increased risk of diarrhea, respiratory disease, and death. Even mild vitamin A deficiency has been associated with a 14- to 10-fold increase in mortality, and controlled field trials have demonstrated vitamin A supplementation can reduce childhood death rates by 30%-70%. Three general intervention strategies exist for improving vitamin A status of high-risk, rural, economically deprived populations. These include nutrition education leading to increased dietary intake; vitamin A fortification of centrally processed, widely consumed dietary items; and periodic administration of large doses of vitamin A. At present, the latter is far and away the most widely employed intervention activity, because of its immediate impact, and because it can be implemented through the existing (and specialized) health care infrastructure. Vitamin A is a fat-soluble vitamin stored in the liver, so that a large dose of 200,000 IU (100,000 IU for children under 1 year of age) every 6 months reduces mortality, stimulates growth, and prevents xerophthalmia and nutritional blindness. Recent data suggest more frequent administration, every 3 to 4 months, may be desirable. Side effects have been minimal, with mild nausea, vomiting, and headaches in less than 1% to 4% of recipients. Care should be taken, however, that doses above 10,000 IU not be administered to women during the first trimester of pregnancy because of potential teratogenic effects.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Large dose vitamin A to control vitamin A deficiency. 250 5

Vitamin A (retinol) deficiency causes blindness, increased morbidity, and mortality among preschool children in many developing nations. Previous studies suggest that impression cytology may represent the first simple, reliable test to detect mild xerophthalmia in young children. We used impression cytology to evaluate and follow up 75 Indonesian preschool children with mild xerophthalmia and an equal number of age-matched, clinically normal neighborhood controls. Results of impression cytology, which were closely correlated with baseline serum vitamin A levels, documented histologic improvement following treatment with vitamin A. Furthermore, results of impression cytology, where abnormal, improved to normal following vitamin A treatment in a significant percentage (23%) of otherwise clinically normal children. Impression cytology appears to detect clinical and physiologically significant preclinical vitamin A deficiency.
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PMID:Impression cytology for detection of vitamin A deficiency. 330 20

Vitamin A has been determined in tear fluid and blood plasma of marginally nourished Thai children before and after supplementation with a single, oral dose of 110 mg retinyl palmitate. After two months a significant rise of tear fluid retinol levels of the supplemented group was observed as compared to the non-supplemented group, while after four months no difference could be found. Determination of vitamin A levels in tear fluid may be useful in clinical eye research, with special regard to xerophthalmia.
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PMID:The effect of vitamin A supplementation on tear fluid retinol levels of marginally nourished preschool children. 335 4


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