Vitamin A deficiency in pre-school age Congolese children during malarial attacks. Part 2: Impact of parasitic disease on vitamin A status

The vitamin A status of 454 pre-school age Congolese children was evaluated by the impression cytology method with transfer (ICT) and by the determination of plasma retinol. During malarial attacks, the vitamin A status is abnormal (deficient or marginal) in 40.8% of the children according to the ICT test and in 37.5% of the children who have plasma levels of retinol lower than 10 micrograms/dl. The mean concentration of plasma retinol in patients during malarial attacks (14.8 +/- 9.5 micrograms/dl) is significantly lower than the values found in other subjects (31.5 +/- 14.3 micrograms/dl) (p less than 0.001). A significant correlation was established between the results of the ICT test and two biochemical parameters (retinol, transthyretin). We conclude that there is a significant relationship between vitamin A deficiency and a malarial attack.     

Assessment of vitamin A status in an elderly French population using impression cytology with transfer

The vitamin A status of 105 elderly French people was assessed by ocular impression cytology with transfer (ICT). 5 patients (4.8%) had a negative ICT defined by the absence of goblet cells and the enlargement of the epithelial cells (deficient vitamin A status). 100 patients had a positive ICT with goblet cells and small, numerous epithelial cells (sufficient vitamin A status). ICT results were compared to serum biochemical parameters. Mean serum levels of retinol, retinol-binding protein (RBP) and transthyretin (TTR) were significantly lower while C-reactive protein (CRP) and orosomucoid were significantly higher in negative ICT than in positive one. The etiology of vitamin A deficiency is difficult to conclude (malnutrition, vitamin A deficiency, inflammation). ICT is a good indicator of peripheral vitamin A deficiency in our experience.     

Impression cytology with transfer: an easy method for detection of vitamin A deficiency

We described a new method to stain epithelial cells harvested by ocular impression. The cells are immediately transferred on a glass slide after the sampling; this transfer permits a very simple staining and easier reading by light microscopy. The results are compared with those obtained with the previous techniques and confirm ocular impression as a good help for vitamin A status determination.     

Assessment of vitamin A deficiency in Republic of Malawi by impression cytology method.

During a countrywide survey, we assessed the prevalence of vitamin A deficiency by impression cytology method with transfer in a randomized sample of 650 representative of the children's population of the Republic of Malawi. A vitamin A deficiency was indicated by the results of the ophthalmic examination (XN = 1,4%; X2 = 0,2%) and the ICT test (22% with deficient cytology). Results of ICT were related to age. Vitamin A deficiency seems to be a public health problem in the Republic of Malawi.     

Conjunctival impression cytology with transfer as a field-applicable indicator of vitamin A status for mass screening.

The increasing importance of vitamin A deficiency in even its mild subclinical form underlines the need for a mass screening test. Clinical, biochemical and cytological methods of assessing vitamin A deficiency in a public health setting have been described and widely used. The cytological method shows promise because it enables early detection of vitamin A deficiency. However interpretation is problematic since histopathological changes are gradual with the progressive disappearance of goblet cells and appearance of enlarged epithelial cells. The reliability and validity of the impression cytology with transfer (ICT) test were assessed in order to produce a meaningful standard for this cytological method. The ICT test was performed in Senegal on 1451 children, in the course of two surveys conducted in 1989 and 1990 in rural areas. Reliability, estimated by Cohen's kappa test for evaluating intra-reader variability, and sensitivity were highest for the abnormal-normal classification (kappa = 0.91; 95% confidence interval (CI): 0.89-0.93; and sensitivity = 74%; 95% CI 66-82%). The ICT method is a cheap, noninvasive and easy test to perform in the field. This method is also reproducible and fairly sensitive according to the abnormal-normal classification. As illustrated by our proposed 50% cutoff of abnormal cytology calculated in relation to 5% of serum retinol values below 0.35 mumol/L criterion, ICT only requires a small sample for the assessment of the overall health of a community in contrast to xerophthalmia and blood vitamin A deficiency tests.     

Vitamin A deficiency is prevalent in children less than 5 y of age in Nigeria

Vitamin A deficiency (VAD) is a serious and widespread public health problem in developing countries. We conducted a nationwide food consumption and nutrition survey in Nigeria to help fomulate strategies to address VAD, among other deficiencies. One objectives was to assess the vitamin A status of children <5 y old. A total of 6480 households with a mother and child <5 y old were randomly sampled. Blood samples were collected by venipuncture and processed to obtain serum for measurement of retinol concentration by HPLC. Nationwide, 29.5% of children <5 y old were vitamin A deficient (serum retinol <0.70 micromol/L). The proportions of children with VAD differed among the agroecological zones; incidences were 31.3% in the dry savanna, 24.0% in the moist savanna, and 29.9% in the humid forest (P < 0.001). More children (P < 0.05) with severe deficiency (serum retinol < 0.35 micromol/L) lived in the humid forest (7.1%) than in the dry (3.1%) or moist savanna (2.4%). The distribution of VA in children <5 y old was 25.6% in the rural sector, 32.6% in the medium, and 25.9% in the urban sector (P < 0.05). In conclusion, VAD is a severe public health problem in Nigeria. Although the proportion of children with low serum vitamin A levels varies agroecologically and across sectors, it is an important public health problem in all zones and sectors.     

Prevalence of malnutrition and vitamin A deficiency in the Diourbel, Fatick, and Kaolack regions of Senegal: feasibility of the method of impression cytology with transfer

The evaluation of the prevalence of ophthalmological diseases and vitamin A deficiency in Senegalese preschool-aged children enabled us to confirm the method of impression cytology with transfer (ICT) and to assess the impact of ophthalmological diseases on the cytological appearance of conjunctival cells. A simplification of the ICT method consisted of transferring cells present on a strip of paper to a glass slide by finger pressure. Harris-Schorr staining of the sample papers confirmed the results obtained by the transfer. Inflammatory trachoma influenced the results of the test. This simple method will prove very helpful for detection of vitamin A deficiency in children in underdeveloped areas.     

Conjunctival impression cytology (CIC) to detect subclinical vitamin A deficiency: comparison of CIC with biochemical assessments

By use of sensitivity and specificity analysis, conjunctival impression cytology (CIC) was compared with fasting serum vitamin A levels and relative dose response (RDR) of Guatemalan children. One impression was taken from the temporal bulbar aspect of each eye, fasting serum vitamin A levels were then drawn, 480 RE of oil-based retinyl palmitate was given, and a 5-h postdosing vitamin A level was drawn (RDR procedure). For a 20% RDR cutoff, the sensitivity of CIC was 23% with a specificity of 80% and a positive predictive value of 9% (n = 213 children). Compared with fasting vitamin A levels alone (with 0.70 mumol/L as abnormal), the sensitivity of CIC was 26%, specificity was 81%, and positive predictive value was 22% (n = 221 children). There was no significant difference in the mean serum retinol level between those with abnormal and normal CIC. In this study population CIC does not identify the same group of children with marginal vitamin A as identified biochemically.     

Assessment of vitamin A deficiency in a rural area in Mali. Estimation of sample size for the impression cytology test.

The prevalence of vitamin A deficiency among two to ten years old children in a rural area of Mali was assessed by ophthalmic examination, determination of plasma retinol levels and impression cytology with transfer tests. A Public Health problem of vitamin A deficiency was identified in this rural area by: the prevalence of nightblindness significantly (p < 0.001) above the cut-off (1%) defined by the World Health Organization (WHO); the prevalence of corneal scarring significantly (p < 0.001) above the WHO's cut-off (0.05%); the percentage of subjects with plasma retinol levels below 0.35 mumol/l (10 micrograms/dl) significantly (p < 0.001) higher than the WHO's threshold (5%); and 52.8 +/- 8.2% children with "Abnormal" impression cytology as determined by the impression cytology test (IC). This preliminary survey confirmed widespread vitamin A deficiency in Mali. The minimum sample size required for a study using the impression cytology test to determinate a Public Health problem in a population was calculated for different situations. Ophthalmic examination indicated a very high rate of active trachoma (29.6 +/- 7.0%), and a relationship between active trachoma and impression cytology results was identified.     

Vitamin A deficiency in children with acute diarrhoea: a community-based study in Bangladesh

The prevalences of nightblindness and xerophthalmia were assessed in 400 children, aged 6-59 months, with acute diarrhoea in a rural community in Bangladesh. The prevalences of nightblindness, conjunctival xerosis, and Bitot's spot were 7.8%, 9.5%, and 2.7% respectively. Fifty-two percent of the children who complained of nightblindness had ocular signs of vitamin A deficiency compared to 9% of those without nightblindness (p < 0.000). The nightblindness was significantly higher among the male children, aged 24-59 months, who were dysenteric and undernourished, did not consume vitamin A-containing foods daily, and were not breastfed. The coverage of periodic administration of vitamin A capsule was inversely related to the prevalence of nightblindness. This finding was determined by logistic regression analysis of data indicating that a combination of male sex, history of dysentery, absence of periodic administration of vitamin A treatment, and daily intake of vitamin A-containing foods gave the best-fitted model with an overall prediction of 92.5% of being nightblind. The findings of the study suggest that mothers should be educated to observe their diarrhoeal children about development of nightblindness and to seek treatment for it. The locally-relevant nutrition education should also be offered to them.     

Vitamin D deficiency and cancer of the breast: an unprovocative ecological hypothesis.

It has been stated recently that atmospheric acid haze containing sulfur dioxide and sulfate crystals may lead to vitamin D deficiencies in exposed populations and increase breast cancer mortality, especially in Montréal. In view of the implications of this hypothesis, we have done a case-control study within the same cohort of women attending the Canadian National Breast Screening Study to check whether a depletion of vitamin D could be detected in the diet of breast cancer patients (n = 108) as compared to controls (n = 322) or a random sample of 1,141 women in our Montréal centre as well as 40 breast cancer cases for which precise food intake data were available by way of a 24-hour dietary journal. The mean daily intake of vitamin D of breast cancer cases was 1.65 +/- 2.48 I.U./kg while in 322 controls matched for age the mean intake was 1.34 +/- 1.17 (S.D.). It has to be pointed out that in the 5 years before diagnosis, cancer patients had not increased significantly their consumption of foods rich in vitamin D, namely milk, cheese, yoghurt, butter and fish. It has also to be stressed that, in relation to the recommended daily intake, twice as many breast cancer patients than controls had a higher consumption of vitamin D.     

Vitamin A deficiency,iron deficiency,and anemia among preschool children in the Republic of the Marshall Islands

OBJECTIVE: We investigated the co-occurrence of vitamin A deficiency, iron deficiency, and anemia among young children in the Republic of the Marshall Islands. METHODS: Hemoglobin, serum retinol, and serum ferritin were assessed in the Republic of the Marshall Islands Vitamin A Deficiency Study, a community-based survey that involved 919 children ages 1 to 5 y. RESULTS: The proportion of children with vitamin A deficiency (serum retinol concentrations < 0.70 microM/L) was 59.9%. The prevalences of anemia (hemoglobin < 110 g/L), iron deficiency (serum ferritin < 12 microg/L), and iron deficiency anemia (iron deficiency and anemia) were 36.4%, 53.5%, and 23.8%, respectively. The proportion of children who had co-occurrence of vitamin A and iron deficiencies was 33.2%. The mean ages of children with and without vitamin A deficiency were 3.2 +/- 1.4 and 2.9 +/- 1.5 y, respectively (P = 0.01), and the mean ages of those with and without iron deficiency were 2.7 +/- 1.3 and 3.5 +/- 1.4 y, respectively (P < 0.0001).CONCLUSIONS: Children in the Republic of the Marshall Islands, ages 1 to 5 y, are at high risk of anemia, vitamin A deficiency, and iron deficiency, and one-third of these children had the co-occurrence of vitamin A and iron deficiencies. Further investigation is needed to identify risk factors and evaluate interventions to address vitamin A and iron deficiencies among children.     

Health visiting and pre-school children with behavioural problems in the County of South Glamorgan: an exploratory study

Summary This study surveys firstly, using a modified semantic differential technique, how a sample of health visitors in the County of South Glamorgan perceived different behavioural problems in preschool children. A selection of visiting records, covering a 1-year period, is also studied. Results from the semantic-differential indicate that health visitors perceive eating and sleeping as the most common problem areas. Hyperactivity and sleeping problems are seen as being the most difficult to deal with and the most disruptive to family life. Although health visitors generally feel it is necessary to follow up children with behaviour problems, they find these difficult to resolve. About one third of children are referred to other agencies. Visiting records reveal that children with hyperactivity and sleeping problems receive the highest number of visits from health visitors and that there is little improvement in these children over a period of 1 year. An extension of the health visitor's role and training to include behavioural treatments for pre-school children is discussed.     

The age at which meat is first included in the diet affects the incidence of iron deficiency and ferropenic anaemia in a group of pre-school children from Madrid

A study was made into the effect of the age at which meat was first included in the diet on a series of haematological parameters and biochemical indicators of iron status in 94 pre-school children (aged 2-6 years) from Madrid (Spain). Those children who first took meat during their eighth month of life or earlier (Group A) showed better iron status that did those who were introduced to meat later (Group B). Significant differences were found in hemoglobin levels (P < 0.01), mean corpuscular haemoglobin (MCH) (P < 0.05), serum ferritin (P < 0.05), transferrin levels (P < 0.05) and total iron binding capacity (TIBC) (P < 0.001). Some 13.8% of all subjects showed iron deficiency and 5.3% showed ferropenic anaemia. These latter subjects were the last to have meat included in their diets (9.3 +/- 1.2 months compared to 7.4 +/- 2.0 months in those without ferropenic anaemia) (P < 0.05). It would appear that the age at which meat is included in the diet has an important effect on iron status in pre-school children. Delaying its inclusion beyond the age of eight months seems to be associated with an impairment of later iron status.     

Vitamin A status and the immune response to pneumococcal polysaccharide: effects of age and early stages of retinol deficiency in rats

Production of antibodies to pneumococcal polysaccharide from Streptococcus pneumoniae, type III was determined in young rats at different ages and stages of vitamin A deficiency. At 30, 35 and 45 d of age, serum retinol concentrations of vitamin A-depleted rats were 46, 35 and 9%, respectively, of the serum retinol concentrations of pair-fed controls. Specific antibody production was low at 30 d of age for both vitamin A-depleted rats and control rats. Between 30 and 45 d of age, antibody production increased considerably in normal rats; however, the response of vitamin A-depleted rats was only 22% (P less than or equal to 0.001) that of controls at 35 d of age and 8% that of controls (P less than or equal to 0.001) for 45-d-old rats. Lymphocyte populations were examined by flow cytometry. The numbers of immunoglobulin M- and immunoglobulin D-positive cells changed with age, but not as a result of dietary treatment. The numbers of total T cells or helper and suppressor T cell subsets did not differ with age or with vitamin A status. These studies showed that the normal antibody response to pneumococcal polysaccharide develops rapidly after 30 d of age in the rat, that this antibody response is impaired even during the early stages of vitamin A deficiency, and that impaired antibody production does not seem to be accompanied by quantitative differences in splenic lymphocyte populations.     

江苏省5岁以下儿童亚临床维生素A缺乏现状研究

为了解江苏省 5岁以下儿童亚临床维生素A缺乏现状 ,采用问卷、体检和实验室检查方法在全省进行抽样调查。结果表明 ,5岁以下儿童亚临床维生素A缺乏率为 13 2 % ,亚临床维生素A缺乏率在城乡之间、性别之间和各年龄组间均无显著性差异 ;预防服药组维生素A缺乏发生率明显低于未服药组。说明江苏省儿童亚临床维生素A缺乏仍较高 ,采取适当干预措施 ,对降低亚临床维生素A缺乏发生率是非常必要的 ,也是有效的。     

Vitamin A deficiency and the metabolism of glycosaminoglycans and ascorbic acid in the rat.

Weanling rats were fed diets with and without the addition of retinyl palmitate at 6,500 units/kg. The supplemented groups were fed either ad libitum or food was restricted daily to that amount consumed by the group of rats receiving the unsupplemented diet. After a 10 week experimental period, signs of vitamin A deficiency were observed (growth plateau, xerophthalmia) and liver values as retinol were only 1% of control values. Relative to the two control groups, vitamin A deficiency resulted in approximately 30% lower liver, 50% lower blood and 40% lower urinary ascorbic acid. Vitamin A deficiency did not appear to result in significant and direct impairment of GAG sulfate metabolism. Although the total amount of GAG in rat skin was increased, the composition of GAG fractions did not appear to be altered by vitamin A deficiency. Studies regarding the incorporation and disappearance of 35S-sulfate in vivo into GAG fractions obtained from skin indicated no serious impairment in GAG turnover with vitamin A deficiency. Twenty-four hour urine samples were also collected for estimation of 35SO4 excreted in GAG and non-GAG fractions. Likewise, little change was observed with respect to radioactivity associated with sulfate fractions excreted in urine. Although many previous studies have directly linked vitamin A with sulfation of GAG, the results reported here suggest that if there is an alteration in GAG sulfate metabolism, it is probably an indirect consequence of vitamin A status.