Assessment of vitamin A status of preschool children in Indonesia using plasma retinol-binding protein

Although plasma retinol-binding protein (RBP) has been proposed as an indicator of vitamin A status of populations in less technologically developed settings, potential factors which could influence this indicator include inflammation and protein energy status. Plasma RBP, retinol, alpha1-acid glycoprotein (AGP), C-reactive protein (CRP), and albumin were measured in a study of 236 preschool children in Bandung, Indonesia. Spearman correlation coefficient between plasma RBP and retinol concentrations was 0.55 (p < 0.0001). By linear regression, 0.70 pmol/l retinol was equivalent to 0.69 micromol/l RBP. With these cut-off points for defining vitamin A deficiency and plasma retinol as the standard for comparison, RBP had a sensitivity and specificity of 75.0 per cent and 63.2 per cent, respectively. The correlation between RBP and retinol was not affected by plasma AGP, CRP, or albumin concentration. Measurement of plasma RBP by radial immunodiffusion is simple and inexpensive, and this test can be used as a simple surrogate measure for vitamin A concentrations in large field studies.     

The effect of vitamin A status in children treated for cancer

Chemotherapy for cancer can cause immunocompromise. The authors speculated that children with cancer and low vitamin A plasma levels were more susceptible to cancer treatment-related complications than children who are not vitamin A deficient. A cohort of 49 children with cancer were followed from diagnosis until death or for at least 5 years. Plasma retinol levels were determined at diagnosis. Complications of treatment were recorded. Children with low retinol levels at diagnosis tended to have more chance to develop febrile neutropenia (p = .052). Children with fever had lower mean vitamin A levels at diagnosis than those who did not suffer febrile episodes. In a childhood population with a high prevalence of vitamin A deficiency, routine vitamin A assessment and supplementation in children with cancer appears indicated.     

Assessment of preclinical vitamin A deficiency in children with persistent diarrhea

To explore the relationship between vitamin A deficiency and persistent diarrhea among young children, we studied the vitamin A status of 23 children greater than 5 years of age with persistent diarrhea by performing conjunctival impression cytology (CIC) and the relative dose-response test (RDR) as a measure of liver reserve of vitamin A. The control group consisted of 23 age- and sex-matched children who were otherwise healthy in whom CIC was performed and fasting plasma retinol values were determined. The criteria for vitamin A deficiency in CIC were paucity of goblet cells and scanty, abnormal epithelial cells. None of these children had ocular manifestations of vitamin A deficiency. Among the children with persistent diarrhea, CIC characteristic of vitamin A deficiency was found in 17 (group 1) and CIC results were normal in six (group 2). In group 1, the serum retinol levels were 1 +/- 1 microgram/dl, and RDR was 88 +/- 14. In group 2, the serum retinol levels were 8 +/- 4 micrograms/dl (p less than 0.001) and the RDR was 16 +/- 12 (p less than 0.001). In the control group, the CIC results were normal in all the children and the plasma retinol levels in these children were 19 +/- 8 micrograms/dl. In conclusion, 17 of 23 children with persistent diarrhea had abnormal CIC results, significantly low serum retinol levels, and significantly high RDR results, although they had not yet manifested xerophthalmia.(ABSTRACT TRUNCATED AT 250 WORDS)     

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目的 评价旱产儿基础维生素A营养状况、与疾病的关系及常规补充的效果.方法 高效液相色谱法检测2006年1月至2007年2月北京大学第一医院出生24 h内的早产儿(147名)血浆视黄醇浓度,足月儿(40名)脐血作为时照.根据临床治疗常规,早产儿静脉(1650U/d)和(或)口服(750U/d)补充维生素A,随访早产儿血浆视黄醇浓度.结果 出生时,早产儿血浆视黄醇浓度低于足月儿,差异有统计学意义,分别为(0.161±0.051)μg/mL和(0.187±0.055)μg/mL(P=0.005).早产儿维生素A缺乏(VAD)发生率高于足月儿,但差异无统计学意义.多元线性回归分析显示出生体重与血浆视黄醇浓度呈正相关.31例早产儿补充维生素A 2周后,随访血浆视黄醇浓度显著升高,分别为(0.168±0.046)μg/mL和(0.203±0.063)μg/mL(P=0.014);VAD发生率显著下降,分别为100%和48%(P<0.001).未发现补充剂量、方式对随访维生素A浓度的影响,未发现出生时血浆视黄醇浓度与新生儿期疾病的关系.结论 早产儿基础维生素A营养状况不良,常规补充可在一定程度上改善2周时维生素A营养状况.     

Postnatal distribution of vitamin A in liver, lung, heart and brain of the rat in relation to maternal vitamin A status

The effect of low, medium and adequate vitamin A (6, 40 and 100 micrograms/day/kg body weight) supplementation to the dams was studied on the accumulation of vitamin A in various tissues of the rat during postnatal growth. The restricted supply of vitamin A to the mother resulted in an impaired growth of pups and their organs. The maternal hepatic stores of vitamin A were related to their vitamin A intake, being lowest in the low group and highest in the adequate group during their fetal development. The plasma vitamin A levels of dams were comparable in three groups at birth and on 10th day of postnatal age. The vitamin A contents of fetal hepatic and extra-hepatic tissues (lung, heart and brain) were increased with the age of pups and this increase was observed to be dependent on the supply of vitamin A to the mother.     

Relationship of milk intake and vitamin K supplementation to vitamin K status in newborns

Vitamin K status was evaluated by measuring blood acarboxyprothrombin (PIVKA-II) levels on the fifth day of life. The incidence of PIVKA-II-positive infants was higher in breast-fed babies than in those given supplementary (mixed) feeding. The median of total amount of milk intake during the first 3 days was significantly lower in PIVKA-II-positive infants than in PIVKA-II-negative infants among infants given both types of feedings. In addition, there was a significant negative correlation between a positive PIVKA-II proportion and the amount of milk intake in the breast-fed babies. The minimum dose of vitamin K2 necessary to prevent a positive PIVKA-II reading was 15 micrograms among babies with a normal absorption potential.     

Assessment of zinc status in man

Conclusions The assessment of human zinc nutritional status has proven to be difficult and challenging task over the course of many years. Dietary and medical history and physical examination may all provide important clues. Of the many laboratory assays for measurement of tissue zinc concentration and functional indices of zinc status, plasma zinc, despite many limitations, remains the assay of choice. Utilization of stable isotope techniques to evaluate zinc homeostasis include measurement of absorption of exogenous zinc, excretion of endogenous zinc and estimation of the combined size of the pools of zinc that are readily available on a whole organism level. Such measurements are starting to yield useful new insights into zinc status. While this approach appears to offer the potential for significant progress on a research basis, it does not provide techniques that are readily applied on a large scale or under ‘field’ conditions. Carefully designed, randomized, placebo controlled supplementation trials are almost invariably required to delineate the clinical and metabolic effects of correcting putative deficiency states. In the case of zinc, these can serve the additional role of confirming the underlying zinc deficiency state.     

Oxidant/antioxidant status and vitamin A levels in children infected with varicella

AIM: Varicella is a childhood disease, with its highest incidence being found in children aged 1 to 9 years. The aim of this study was to investigate the plasma oxidant and antioxidant status in Turkish children with varicella infection. METHODS: The study population consisted of 29 children infected with varicella recruited from the Department of Pediatrics at Baskent University Hospital in Ankara, Turkey. The control group consisted of 20 age-matched children from the same region who were apparently otherwise healthy. After overnight fasting, venous blood samples were obtained and transferred to heparinized tubes. Plasma malondialdehyde and vitamin A levels were measured in both groups. RESULTS: The plasma malondialdehyde levels were higher in children in the infected group than they were in children in the control group. However, there were no statistically significant differences in plasma vitamin A levels between the groups. CONCLUSION: This study suggests that oxidant stress causes significant peroxidation, and the antioxidant defence system is affected in varicella infection. Antioxidant supplementation may yield beneficial results in these patients. Further studies are needed to determine the positive effects of vitamin A supplementation in patients with varicella infections.     

儿童哮喘与亚临床状态维生素A缺乏关系的研究

采用微量荧光测定法对２０例哮喘患儿及３５例健康儿童进行血清维生素Ａ（ＶｉｔＡ）检测。结果表明：各年龄段哮喘患儿血清Ｖｉｔ Ａ水平明显低于正常对照组,尤其是≤３岁组及〉６岁组（Ｐ〈０．００１）。哮喘组亚临床ＶｉｔＡ缺乏发生率为８０％（１６／２０例）,正常对照组为２０．８％（１／３５例）,有显著性差异（Ｐ〈０．００５）。其中≤３岁组最高,占５０．０％（１０／２０例）。结论：儿童哮喘存在着亚临床状态ＶｉｔＡ缺乏,两者可能互为因果关系。     

Assessment of nutritional status in children with cancer: A narrative review

A child's appropriate development stems in large part from proper nutrition. Malnutrition is an adverse prognostic factor in children with cancer, and its prevalence is highly variable. Currently, there is no standardized definition and assessment method of nutritional status in pediatric oncology. A complete nutritional assessment includes anthropometry, biochemical, clinical, and dietary assessments. In this article, we explore these methods and suggest practical approaches for pediatric cancer units depending on the levels of care that these can provide. We also advise on the monitoring and follow‐up of children with cancer during and after treatment, and discuss potential areas for future research.     

Relationship of vitamin A (retinol) status to lung disease in the preterm infant

Plasma concentrations of retinol and retinol-binding protein were measured at birth in 91 preterm infants. In 64% of these babies retinol values were less than 20 micrograms/dl, suggestive of vitamin A deficiency. Forty-seven of these infants were observed with sequential measurements of retinol and retinol binding protein through 21 days of age. In babies with respiratory distress syndrome retinol values were similar to those in babies without respiratory distress syndrome. The retinol binding protein levels were lower on the third day of life in babies with respiratory distress syndrome. Babies who developed bronchopulmonary dysplasia had lower concentrations of retinol at birth (P less than 0.05) and on day 21 (P less than 0.05) than did babies who did not develop bronchopulmonary dysplasia, despite receiving recommended intakes of vitamin A. Many preterm infants are deficient in vitamin A at birth, and failure to correct this deficiency may contribute to the development of chronic lung disease.     

Association of vitamin A status with lung function in children and adolescents with cystic fibrosis

Importance:Vitamin A(or retinol)has considerable antioxidative and anti-inflammatory attributes and it may have protective effects on the respiratory health of ...