Self-Restricted Diet in Pediatric Autism Leading to Vitamin A Deficiency and Severe Photophobia

In developed countries, vitamin A deficiency (VAD) remains rare but is a leading cause of global blindness. We describe the case of a 10-year-old girl with autism spectrum disorder (ASD) initially presenting mild VAD symptoms, escalating to severe photophobia and reluctance to leave a darkened room due to a self-restricted diet of fast-food french fries. A timely examination revealed severe VAD and vitamin A supplementation resolved her symptoms in three weeks. This case highlights the challenge of obtaining accurate patient history in ASD, emphasizing the need for routine dietary discussions and micronutrient testing, especially at ages nine and 13 when the United States Department of Agriculture (USDA) recommends increased vitamin A intake. Early intervention can prevent micronutrient deficiencies in pediatric patients, particularly those with ASD.

Hepatitis A Leading to Severe Vitamin A Deficiency and Bitot's Spots in a Three-Year-Old Male Child: A Case Report

This case presentation details the clinical journey of a three-year-old male child presenting with fever, abdominal distention, and loose stools. The child's symptoms, unresponsive to initial treatment at two hospitals, led to the discovery of elevated liver enzymes and subsequent referral to a tertiary care center. Clinical examination revealed hepatomegaly, abdominal distension, and non-palpable spleen. Laboratory findings confirmed acute hepatitis, prompting further investigation into the child's dietary history and revealing a potential foodborne infection. The child was diagnosed with hepatitis-associated severe vitamin A deficiency, manifested by Bitot's spots on ophthalmic examination. Prompt initiation of antiviral therapy, nutritional supplementation, and supportive care resulted in a positive clinical response, with resolution of symptoms and normalization of liver enzymes. This case underscores the importance of recognizing nutritional deficiencies in the context of infectious diseases, emphasizing the need for a comprehensive approach to patient care. The successful management of this complex case highlights the significance of interdisciplinary collaboration in ensuring optimal outcomes in pediatric patients with overlapping infectious and nutritional etiologies.

A Multifaceted Presentation of Xerophthalmia in Autistic Patients

We report the manifestations of vitamin A deficiency (VAD) in three children with underlying autism of different stages. These children were under developmental paediatrician follow-up for autism, and the VAD was not detected until these children presented to Ophthalmology screening for varying stages of signs and symptoms. On further assessment, all of our patients have VAD secondary to poor dietary intake, as autistic patients are associated with having selective eating habits. In our case series, we discuss the spectrum of xerophthalmia presentations, which can be mild and can manifest as punctate epithelial erosions to the more blinding complications at the advanced stage of the disease, mainly irreversible optic neuropathy. The primary management is to address the dietary routine coupled with systemic administration of vitamin A.

Nutrition transition in Brazilian children under 5 years old from 2006 to 2019

This manuscript aims to report the nutrition transition in Brazilian children under 5 years old from 2006 to 2019. Microdata from the Brazilian National Survey on Demography and Health of Women and Children (PNDS 2006) and the Brazilian National Survey on Child Nutrition (ENANI-2019) were analyzed. The indicators considered were: micronutrient status (anemia and vitamin A deficiency), anthropometric status (stunting and excessive weight), and breastfeeding practice (exclusive breastfeeding among children < 6 months and continued breastfeeding among children 12-23 months). We also analyzed minimum dietary diversity (MDD), consumption of ultra-processed foods, consumption of meat or eggs, and not consuming fruits or vegetables in children 6-59 months of age only for ENANI-2019. Equiplot charts were generated according to geographic region, maternal schooling level, and maternal race/skin color. From 2006 to 2019, the prevalence rates of anemia and vitamin A deficiency decreased from 20.5% to 10.1% and 17.2% to 6%, respectively. The prevalence of stunting remained at 7%, and excessive weight rates increased from 6% to 10.1%. The prevalence of exclusive breastfeeding among children < 6 months increased from 38.6% to 45.8%, and of continued breastfeeding among children 12-23 months from 34.6% to 43.6%. In 2019, 61.5% of children achieved the MDD, 88.8% consumed ultra-processed foods, 83.1% consumed meat or egg, and 25.7% did not consume fruits or vegetables the day before the survey. Trends of decreased micronutrient deficiencies, increased breastfeeding, and excessive weight rates, as well as reductions in disparities related to geographic region, maternal schooling level, and maternal race/skin color, were observed for most of the indicators.

Nyctalopia and Xerophthalmia in a Patient With Crohn's Induced Vitamin A Deficiency

The vitamin A derivative, retinal, plays a pivotal role in scotopic and color vision. Although vitamin A deficiency (VAD) presents as a common cause of preventable blindness in areas with poor access to foods rich in vitamin A, it is uncommon in developed countries. We present a 56-year-old male with a history of Crohn's disease and pancreatitis who was referred to our ophthalmology office by optometry for severe dry eyes. He complained of a two-year history of constant blurred vision and nyctalopia. He stated that "images just appear dark." Examination demonstrated mildly decreased visual acuity with severe ocular surface disease and characteristic Bitot's spots in both eyes. Based on the patient's history and physical, a diagnosis of xerophthalmia in the setting of VAD was made. The patient was referred to his internist, he then underwent further evaluation and treatment with vitamin A intramuscular injections post-diagnosis.  This case illustrates the potential for VAD secondary to malabsorption from Crohn's disease and the importance of taking a full patient history so systemic causes of ophthalmic symptoms may be promptly identified and treated. VAD is extremely rare in the United States, however, patients at risk for VAD may benefit from regular vitamin A level checks and ophthalmologic evaluation.

Vision Loss in a Healthy Child: A Case of Vitamin A Deficiency

Vitamin A deficiency (VAD) is common in developing countries but rare in resource-rich countries. In developed countries, malabsorption and behavioral issues are more common reasons for VAD. The current case is an example of a healthy child who developed ocular symptoms due to vitamin A deficiency in the setting of cultural influences and emotional stressors.

DISRUPTION OF THE OUTER SEGMENTS OF THE PHOTORECEPTORS ON OPTICAL COHERENCE TOMOGRAPHY AS A FEATURE OF VITAMIN A DEFICIENCY

PURPOSE

To describe the optical coherence tomography features of vitamin A deficiency.

METHODS

Case series includes three male patients aged 50 to 66 years with vitamin A deficiency and visual symptoms ranging from 2 to 8 months. Examination included optical coherence tomography (OCT), fundus autofluorescence imaging, full-field electroretinography6 and laboratory work-up.

RESULTS

Patient 1 had inoperable pancreatic neuroendocrine tumor and presented with worsening nyctalopia. The electroretinography showed absent rod function 2 months after the onset of symptoms, followed by a decrease of the cone function eight months after the onset. Optical coherence tomography showed poorly distinguishable outer segments of the photoreceptors with the disappearance of the interdigitation zone. At that time, vitamin A deficiency along with several other deficiencies was confirmed. After the initiation of parenteral nutrition, a substantial improvement of the patient's overall well-being was noted and the OCT showed normalization of the retinal structure. Two other patients were diagnosed with vitamin A deficiency based on similar OCT features.

CONCLUSION

Disruption of the outer segments of the photoreceptors and the disappearance of the interdigitation zone on OCT may be helpful in recognition of vitamin A deficiency. Early detection and malnutrition evaluation are especially important in patients with a history of gastrointestinal disorders who may have several other underlying deficiencies. Treatment with either enteral or parenteral nutrition not only leads to resolution of visual symptoms but vastly improves their general condition and quality of life.

The structural effects of Vitamin A deficiency on biological macromolecules due to ethanol consumption and withdrawal: An FTIR study with chemometrics

The structural effects of vitamin A-deficiency were examined on the molecular profiles of biomolecules of male rat hippocampus during prolonged ethanol intake/withdrawal using FT-IR spectroscopy coupled with chemometrics. Liquid ethanol diet with/without vitamin A was maintained to adult rats for 3-months. The rats were decapitated at different ethanol withdrawal times and FT-IR spectra were obtained. Ethanol consumption/withdrawal produced significant changes in proteins' conformations, while having insignificant structural effects on lipids. In vitamin A deficiency, ethanol produced structural changes in lipids by lipid ordering especially in the early-ethanol withdrawal. Furthermore, an increase in lipid and protein content, saturated/unsaturated lipid ratio, a decrease in nucleic acids content and decrease in membrane fluidity were observed. These changes were less severe in the presence of Vitamin A. This study is clinically important for individuals with vitamin A deficiency because they have to be more cautious when consuming alcohol to protect themselves from cognitive dysfunctions.

Recognizing vitamin A deficiency: special considerations in low-prevalence areas

PURPOSE OF REVIEW

Although vitamin A deficiency (VAD) is rare in well resourced countries, there is a growing trend of VAD in at-risk pediatric populations. Early diagnosis is critically important to prevent its associated morbidity and mortality. This review highlights key lessons for evaluation, diagnosis, and management of children with xerophthalmia in the United States. It synthesizes the latest findings from the literature on the pathophysiology, epidemiology, risk factors, evaluation, and management of VAD in low-prevalence areas.

RECENT FINDINGS

Vitamin A is crucial for maintaining the functional integrity of the eye, immune system, skin, and mucous membranes. Despite the scarcity of VAD in developed countries, there are increasing reports of VAD in at-risk children, including those with autism spectrum disorder and gastrointestinal conditions. There is a broad range of manifestations of VAD, posing a diagnostic challenge. Familiarity with the variable presentations of VAD and having a high index of suspicion in at-risk populations can aid in its early diagnosis. Systemic vitamin A supplementation and a multidisciplinary approach are important components of the management of VAD.

SUMMARY

Even in well resourced countries, VAD should remain on the differential in patients with risk factors who present with relevant signs and symptoms. Early diagnosis and appropriate involvement of a multidisciplinary care team can help prevent morbidity and mortality associated with VAD.

Interrelations between Iron and Vitamin A-Studied Using Systems Approach

A deficiency of vitamin A (VAD) and iron is the most common nutritional problem affecting people worldwide. Given the scale of the problem, the interactions between vitamin A and iron levels are widely studied. However, the exact mechanism of the impact of vitamin A on the regulation of iron metabolism remains unclear. An extremely significant issue becomes a better understanding of the nature of the studied biological phenomenon, which is possible by using a systems approach through developing and analyzing a mathematical model based on a Petri net. To study the considered system, the t-cluster analysis, the significance analysis, and the analysis of the average number of transition firings were performed. The used analyses have allowed distinguishing the most important mechanisms (both subprocesses and elementary processes) positively and negatively regulating an expression of hepcidin and allowed to distinguish elementary processes with a higher frequency of occurrence compared to others. The analysis also allowed to resolve doubts about the discrepancy in literature reports, where VAD leads to positive regulation of hepcidin expression or to negative regulation of hepcidin expression. The more detailed analyses have shown that VAD more frequently positively stimulates hepcidin expression and this mechanism is more significant than the mechanism inhibiting hepcidin expression indirectly by VAD.

Complementary Feeding Indicators in Relation to Micronutrient Status of Ghanaian Children Aged 6-23 Months: Results from a National Survey

BACKGROUND

Optimal complementary feeding is critical for adequate growth and development in infants and young children. The associations between complementary feeding and growth have been studied well, but less is known about the relationship between complementary feeding and micronutrient status.

METHODS

Using data from a national cross-sectional survey conducted in Ghana in 2017, we examined how multiple WHO-recommended complementary feeding indicators relate to anemia and the micronutrient status of children aged 6-23 months.

RESULTS

In total, 42%, 38%, and 14% of the children met the criteria for minimum dietary diversity (MDD), minimum meal frequency (MMF), and minimum acceptable diet (MAD), respectively. In addition, 71% and 52% of the children consumed iron-rich foods and vitamin A-rich foods, respectively. The prevalence of anemia, iron deficiency (ID), iron deficiency anemia (IDA) and vitamin A deficiency (VAD) was 46%, 45%, 27%, and 10%, respectively. Inverse associations between MMF and socio-economic status were found, and MMF was associated with an increased risk of ID (55%; p < 0.013) and IDA (38%; p < 0.002).

CONCLUSION

The pathways connecting complementary feeding and micronutrient status are complex. Findings related to MMF should be further investigated to ensure that complementary feeding programs account for the potential practice of frequent feeding with nutrient-poor foods.

PLACK syndrome is potentially treatable with intralipids

We describe an 11-year-old girl with PLACK Syndrome (peeling skin, leukonychia, acral punctate keratosis, cheilitis, and knuckle pads), who was found to have a novel homozygous variant in CAST, the pathogenicity of which was confirmed using blood-derived RNA. There is no established treatment for PLACK syndrome. However, we demonstrate for the first time that this condition is associated with low levels of vitamin A and essential fatty acids, which prompted us to consider a potential treatment strategy. Indeed, we initiated this patient on intravenous lipid infusion (Vitalipid®; an emulsion of fat-soluble vitamins and lipofundin-MCT/LCT 20%) and the response was dramatic. Following the fourth monthly course of treatment, pruritis disappeared and the skin lesions showed remarkable objective improvement. PLACK syndrome is a very rare genodermatosis and only six families have been described to date with pathogenic CAST variants. This is the first report of an objective response to a therapeutic agent, which suggests that PLACK is a potentially treatable condition. The remarkable response we report and the relative safety of the intervention should prompt healthcare providers who care for PLACK syndrome patients to explore this as a potential treatment strategy in future studies.

Impact of behaviour change communication interventions on sales of fortified sunflower oil in Tanzania: A spatial-temporal analysis and association study

The Masava project was implemented in Manyara and Shinyanga regions in Tanzania to improve vitamin A intake by making available vitamin A-fortified sunflower oil with a subsidy through a mobile phone-based e-Voucher system. This study was conducted to assess the impact of the behaviour change communication (BCC) campaign of the project on volume of sales of vitamin A-fortified sunflower oil. The e-Voucher system provides real-time data on the number of e-Vouchers redeemed. The number, type, and locations of BCC events were obtained from the implementation agency. Multivariate linear regression was used to examine the associations between (a) the number and type of BCC events conducted in a ward and the volume of subsequent fortified oil redeemed in the ward and (b) distance of clinic shows, a component of the BCC campaign, from participating retailers and the volume of fortified oil redeemed in the store. After 1 year of the campaign, the volume of fortified oil redeemed monthly increased by more than 5 times in Manyara and by more than three times in Shinyanga. Among the different types of BCC events conducted, only clinic shows and cooking shows were significantly associated with the volume of redemptions (p < .05). Compared with retailers where at least one clinic show was conducted within 0.5 km from its location, the volume of redemptions was significantly lower at retailers where no clinic show conducted within 3.0 km from its location (p < .05). These findings suggest that future health promotion interventions in rural Africa should involve health clinics.

Case report: Ribavirin and vitamin A in a severe case of measles

RATIONALE

Despite a vaccine being widely available, measles continues to occur frequently, with sometimes lethal consequences.

PATIENTS CONCERNS

The mortality rate reaches 35% and measles represents 44% of the 1.4 million deaths which are due to preventable diseases. Severe forms of measles are reported, mainly in young, unvaccinated adults, and in specific populations. The risk factors for severe measles include no or incomplete vaccination and vitamin A deficiency. Apart from secondary measles-related infections, severe measles is mainly represented by neurological, respiratory, and digestive symptoms.

DIAGNOSES

Strengthening the hypothesis that there is a link between vitamin A deficiency and severe measles in this paper we report the case of a 25-year-old unvaccinated man hospitalized for severe and complicated measles.

OUTCOMES

The evolution was good after administration of intramuscular vitamin A as well as intravenous ribavirin.

LESSONS

Measles remains a fatal and serious disease. The early use of ribavirin and vitamin A shows significant improvements regarding morbimortality and should be systematic in severe cases.

Nutritional, inflammatory, and ecological correlates of maternal retinol allocation to breast milk in agro-pastoral Ariaal communities of northern Kenya

OBJECTIVES

Vitamin A (VA) is an essential micronutrient required for a range of biological functions throughout life. VA deficiency (VAD) claims an estimated 1 million preschool children's lives annually. Human milk is enriched with VA (retinol) from the maternal blood, which originates from the hepatic reserve and dietary intake. Secreting retinol into milk will benefit the nursing infant through breast milk, but retaining retinol is also important for the maternal health. Previous studies found that the public health intervention of high-dose VA supplementation to lactating mothers did not significantly lower child mortality. The World Health Organization (WHO) recently acknowledged that our understanding about the principle of VA allocation within the maternal system and the secretion into milk is too incomplete to devise an effective intervention.

METHODS

We present a secondary analysis of data collected among lactating mothers in VAD endemic northern Kenya (n = 171), examining nutritional, inflammatory, and ecological factors that might associate with maternal retinol allocation. Regression models were applied using the outcome milk-retinol allocation index: milk retinol/(milk retinol + serum retinol).

RESULTS

Ten percent of the sample was identified as VAD. The average milk retinol concentration was 0.1 μmo/L, grossly below what is considered minimally necessary for an infant (1 μmol/L). VAD mothers and mothers with inflammation did not seem to compromise their milk retinol even though their serum retinol was lower than non-VAD and noninflammation mothers. Breast milk fat concentration positively correlated with milk retinol but not with serum retinol.

CONCLUSIONS

This exploratory study contributes toward an understanding of maternal retinol allocation.

Reappearance of Bitot's spots after complete resolution in children between 1 and 5 years of age

There is limited data on proportion of Bitot's spots (BS), which could reappear after receiving mega dose of Vitamin A (MDVA), and their complete resolution. A prospective, community-based, cohort study with 12 months follow-up was conducted among children (1-5 years) with BS at a district from North India. On diagnosis, 200,000 IU of vitamin A was administered on the same day, then after 4 weeks and subsequently after 6 months. Out of 262 children with BS, 157 (59.9%, 95% CI: 54.1-65.9) children had shown resolution of BS after the MDVA supplementation. Out of 157 children, 97 (61.8%, 95% CI: 54.2-69.4) had reappearance of BS after complete resolution. Kaplan-Meir analysis found that median duration of reappearance of BS was 5 months (95% CI: 3.8-6.2) after their complete resolution. The reappearance of BS after administration of two MDVA within 12 months suggests that children with possibly adequate serum retinol level status may have reappearance of BS.

Proxy markers of serum retinol concentration, used alone and in combination, to assess population vitamin A status in Kenyan children: a cross-sectional study

BACKGROUND

Serum retinol concentration determined by high-performance liquid chromatography (HPLC) is recommended by the World Health Organization to assess population vitamin A status. This assay is expensive, technically demanding and rarely available in developing countries. Our objective was a) to assess the diagnostic performance of proxy markers in detecting vitamin A deficiency and b) to derive decision rules based on these markers to estimate vitamin A deficiency prevalence.

METHODS

A survey was conducted in 15 rural primary schools in Eastern Province, Kenya, with 375 children aged 6 to 12 years (25 randomly selected per school). Serum retinol concentration <0.70 μmol/L by HPLC was used to define vitamin A deficiency. Proxy markers for vitamin A deficiency were serum concentrations of retinol binding protein (RBP), transthyretin, retinol measured by fluorometry and RBP:transthyretin molar ratio.

RESULTS

The prevalence of vitamin A deficiency (HPLC) was 18%. Transthyretin and RBP showed the best diagnostic performance individually, with area-under-the-curve (AUC) values of 0.96 and 0.93. When combined, and with C-reactive protein added, the AUC increased to 0.98. A simple decision rule {(-15.277 × [RBP, μmol/L] - 7.013 × [Transthyretin, μmol/L] + 0.367 × [C-reactive protein, mg/L] + 24.714) > 0.496} yielded prevalence estimates of vitamin A deficiency that is unbiased by diagnostic error.

CONCLUSIONS

The combination of transthyretin, RBP and C-reactive protein concentrations could eventually replace retinol concentration by HPLC in resource-poor settings as the preferred method to assess the population burden of vitamin A deficiency.

Resolution of Bitot's spots following mega-dose vitamin A supplementation in children between 1 and 5 years of age

OBJECTIVE

The prevalence of Bitot's spots (BS) is often used to quantify vitamin A deficiency burden in India, both before and after mega-dose vitamin A supplementation (MVAS) programmes. However, the proportion of BS cured following this intervention is unclear in contemporary times. The current study evaluated the responsiveness of BS over 1 year to MVAS administered as per the national programme in rural India.

DESIGN

Prospective, community-based, 1-year follow-up of a cohort.

SETTING

Rural Uttar Pradesh, India.

SUBJECTS

Two hundred and sixty-two children with BS, aged between 1 and 5 years, administered 60 mg (retinol equivalent) of vitamin A on diagnosis and after 1 month. Cure or resolution was defined if there was no discernible BS in either eye.

RESULTS

During 1 year, only three children were lost to follow-up. At 6 months of follow-up (MVAS at baseline and 1 month later), 51·1 (95% CI 45·3, 57·3) % were classified as cured. The corresponding figure at 1 year (additional MVAS at 6 months) was 59·9 (95% CI 54·1, 65·9) %. Among those cured at 6 months, about half and three-quarters had resolved at 2 and 3 months, respectively. Apart from male gender, there were no significant sociodemographic or clinical predictors of response.

CONCLUSIONS

Substantial non-response to MVAS at 6 months (49%) and 1 year (40%) of follow-up suggests that presently in the Indian subcontinent, BS is a relatively crude indicator of severe current vitamin A deficiency. For programmatic decisions and evaluation, the public health burden of vitamin A deficiency should not be assessed solely through BS.

Serum retinol concentrations in mothers and newborns at delivery in a public maternity hospital in Recife, northeast Brazil

Serum retinol concentrations were compared in a consecutive series of 65 mother-newborn pairs at delivery in a public maternity hospital in Recife, Brazil, from January to August 2008 and examined their association with biological, socioeconomic, environmental and obstetrical characteristics. Serum retinol concentrations of the newborns (umbilical cord) and mothers (brachial venipuncture) were analyzed by high-performance liquid chromatography. Prevalence of low (< 0.70 micromol/L) and inadequate (< 1.05 micromol/L) serum retinol concentrations were observed in 23.1% (95% CI 13.9-35.5) and 23.0% (95% CI 13.5-35.8) among newborns and mothers respectively. The serum retinol distribution was lower in male than female infants (-0.4 micromol/L, p = 0.01) and, across both sexes, concentrations in paired newborn and mother were correlated (r = 0.27, p = 0.04). Further, maternal status explains only 7% of the variance in retinol concentrations in newborn's cord plasma. Among mothers delivering in public facilities in Recife, hypovitaminosis may exist.

Marker-trait association analysis of functional gene markers for provitamin A levels across diverse tropical yellow maize inbred lines

BACKGROUND

Biofortification of staple crops is a cost effective and sustainable approach that can help combat vitamin A and other micronutrient deficiencies in developing countries. PCR -based DNA markers distinguishing alleles of three key genes of maize endosperm carotenoid biosynthesis (PSY1, lcyE and crtRB1) have been developed to facilitate maize provitamin A biofortification via marker assisted selection. Previous studies of these functional DNA markers revealed inconsistent effects. The germplasm previously employed for discovering and validating these functional markers was mainly of temperate origin containing low frequencies of the favourable allele of the most significant polymorphism, crtRB1-5'TE. Here, we investigate the vitamin A biofortification potential of these DNA markers in a germplasm panel of diverse tropical yellow maize inbred lines, with mixed genetic backgrounds of temperate and tropical germplasm to identify the most effective diagnostic markers for vitamin A biofortification.

RESULTS

The functional DNA markers crtRB1-5'TE and crtRB1-3'TE were consistently and strongly associated with provitamin A content across the tropical maize inbred lines tested. The alleles detected by these two functional markers were in high linkage disequilibrium (R2 = 0.75) and occurred in relatively high frequency (18%). Genotypes combining the favourable alleles at the two loci (N = 20) displayed a 3.22 fold average increase in β-carotene content compared to those genotypes lacking the favourable alleles (N = 106). The PSY1 markers were monomorphic across all of the inbred lines. The functional DNA markers for lcyE were associated with lutein, and with the ratio of carotenoids in the alpha and beta branches, but not with provitamin A levels. However, the combined effects of the two genes were stronger than their individual effects on all carotenoids.

CONCLUSIONS

Tropical maize inbred lines harbouring the favourable alleles of the crtRB1-5'TE and 3'TE functional markers produce higher levels of provitamin A. Such maize lines can be used as donor parents to speed up the development of provitamin A biofortified tropical maize varieties adapted to growing conditions and consumer preferences, providing a route towards mitigation of vitamin A malnutrition in Sub-Saharan Africa.

Prevalence and correlates of prenatal vitamin A deficiency in rural Sidama, Southern Ethiopia

A cross-sectional study was conducted to assess the prevalence and correlates of prenatal vitamin A deficiency (VAD) in rural Sidama, Southern Ethiopia. Seven hundred randomly-selected pregnant women took part in the study. Serum retinol concentration was determined using high-performance liquid chromatography. Data were analyzed by logistic and linear regression. Interpretation of data was made using adjusted odds ratio (AOR) and adjusted linear regression coefficient. The prevalence of VAD (serum retinol < 0.7 micromol/L) was 37.9%. Advanced gestational age and elevated C-reactive protein (CRP > or = 5 mg/dL) were negatively associated with retinol concentration (p < 0.05). The odds of VAD was significantly higher among the women with no education and those devoid of self-income. Women aged 35-49 years had 2.23 (95% CI 1.31-3.81) times higher odds compared to those aged 15-24 years. The lower the dietary diversity score in the preceding day of the survey, the higher were the odds of VAD. With reference to nulliparas, grand multiparas had 1.92 (95% CI 1.02-3.64) times increased odds of VAD. VAD and zinc deficiency (serum zinc <8.6 pmol/L during the first trimester, or <7.6 pmol/L during the second or third trimester) were significantly associated with AOR of 1.80 (95% CI 1.28-2.53). VAD has major public-health significance in the area. Accordingly, it should be combated through enhancement of diet diversity, birth control, and socioeconomic empowerment of women.

Prevalence of vitamin A deficiency in pregnant and lactating women in the Republic of Congo

Vitamin A status in a sample of pregnant and lactating women living in several representative regions of Congo was assessed and compared between August and September 2004. This survey was conducted using a randomized two-stage cluster-sampling method with stratification on 90 clusters, each consisting of at least 15 women. Vitamin A status was determined in a total of 1,054 individuals, using the impression cytology with transfer (ICT) test, the modified relative dose response test (MRDR test) on dried blood spots (DBS), and clinical examination to detect signs of xerophthalmia. The clinical criterion defining vitamin A deficiency was the presence of active xerophthalmia (Bitot's spots [X1B]), active corneal disease), and/or night blindness (XN stage). The prevalence of clinical signs of stage XN and X1B xerophthalmia in the Republic of Congo was found to be 16% and 19% respectively. The prevalence of clinical signs (X1B) was greater in the rural north than in urban areas, with a gradient running from urban (5%) to rural area (33%); 27% of all the ICT tests showed that the subjects were suffering from vitamin A deficiency. The deficiency rates were significantly higher (p < 0.001) in urban surroundings (Brazzaville) than in the rural northern regions. The biochemical MRDR test showed the presence of vitamin A deficiency (> or = 0.06) in 26% of the mothers in Brazzaville compared to 6% in the town of Kouilou; 44% of the women had retinol levels of < 10 microg/dL in the rural north whereas these percentages were significantly lower in the urban areas surveyed (chi-square = 62.30, p < 0.001). A significant correlation was found to exist (p < 0.001) between the ICT test and the MRDR test on DBS. In the population as a whole, 30% of the mothers suffering from malarial attack had abnormally low MRDR levels (> or = 0.06) compared to no malaria. The results of the present study confirm that vitamin A deficiency is a serious public-health issue in pregnant and lactating mothers in the Republic of Congo.

Assessment of vitamin A status of preschool children in a sub-Saharan African setting: comparative advantage of modified relative-dose response test

A nationally-representative sample of 2,696 preschool children living in Congo was examined during Au gust-September 2003 to determine the rates of vitamin A deficiency. Ninety clusters of 30 children, aged six months to six years, were selected, using a randomized two-level cluster-sampling method. Vitamin A deficiency was determined by assessing the prevalence of active xerophthalmia (nightblindness and/or Bitot spots) in the cross-over sample of 2,696 individuals. A semi-quantitative seven-day dietary questionnaire was concurrently applied to the mothers of children enrolled to estimate the latter's consumption of vitamin A-rich food. Vitamin A status was assessed by performing the modified relative dose-response test (MRDR) on dried blood spots (DBS) from a subsample of 207 children aged less than six years and the impression cytology with transfer (ICT) test on a subsample of 1,162 children. Of the children enrolled, 5.2% suffered from nightblindness, 8.0% had Bitot spots, and 2.5% had other vitamin A deficiency sequellae. Fifty-three percent of the ICT tests showed the presence of vitamin A deficiency. The biochemical MRDR test showed that the vitamin A status of 30% of the study children was critical. Twenty-seven of them had retinol levels of < 10 microg/dL [mean +/- standard deviation (SD) 7.02 +/- 2.0 microg/dL], and 50% had retinol levels of 10-20 microg/dL (mean +/- SD 14.2 +/- 2.83 microg/dL). The poor health status and low rates of consumption of vitamin A-rich food are the main factors determining critical status. Vitamin A deficiency, reflecting poor nutrition and health, is a serious public-health issue among children aged less than six years in Congo.

Effect of dietary fat supplementation during late pregnancy and first six months of lactation on maternal and infant vitamin A status in rural Bangladesh

Dietary fat intake is extremely low in most communities with vitamin A deficiency. However, its role in vitamin A status of pregnant and lactating women is poorly understood. The aim of the study was to examine the effect of supplementing women with fat from mid-/late pregnancy until six months postpartum on their vitamin A status and that of their infants. Women recruited at 5-7 months of gestation were supplemented daily with 20 mL of soybean-oil (n = 248) until six months postpartum or received no supplement (n = 251). Dietary fat intake was assessed by 24-hour dietary recall at enrollment and at 1, 3 and 6 months postpartum. Concentrations of maternal plasma retinol, beta-carotene, and lutein were measured at enrollment and at 1, 3 and 6 months postpartum, and those of infants at six months postpartum. Concentration of breastmilk retinol was measured at 1, 3 and 6 months postpartum. The change in concentration of plasma retinol at three months postpartum compared to pregnancy was significantly higher in the supplemented compared to the control women (+0.04 vs -0.07 micromol/L respectively; p < 0.05). Concentrations of plasma beta-carotene and lutein declined in both the groups during the postpartum period but the decline was significantly less in the supplemented than in the control women at one month (beta-carotene -0.07 vs -0.13 micromol/L, p < 0.05); lutein -0.26 vs -0.49 micromol/L, p < 0.05) and three months (beta-carotene -0.04 vs -0.08 micromol/L, p < 0.05; lutein -0.31 vs -0.47 micromol/L, p < 0.05). Concentration of breastmilk retinol was also significantly greater in the supplemented group at three months postpartum than in the controls (0.68 +/- 0.35 vs 0.55 +/- 0.34 micromol/L respectively, p < 0.03). Concentrations of infants' plasma retinol, beta-carotene, and lutein, measured at six months of age, did not differ between the groups. Fat supplementation during pregnancy and lactation in women with a very low intake of dietary fat has beneficial effects on maternal postpartum vitamin A status.

Low-dose beta-carotene supplementation and deworming improve serum vitamin A and beta-carotene concentrations in preschool children of Bangladesh

Despite the national vitamin A and antihelminthic prophylaxis programmes, both intestinal geohelminths and subclinical vitamin A deficiency continue to be prevalent among children in developing countries. Studies on potential synergistic effects of vitamin A supplementation and deworming on retinol status have inconsistent results. The purpose of the present study was to investigate the impacts of low-dose beta-carotene supplementation and antihelminthic therapy on serum retinol and beta-carotene concentrations in preschool children of Bangladesh. Two hundred and forty-four children, known to be infected with Ascaris lumbricoides, were randomized into four treatment groups: I-IV. Group I and II received two oral doses of 400 mg of albendazole each, the first dose at baseline and the second dose after four months; Group III and IV received placebo in place of albendazole. In addition, Group I and III received 1.2 mg of beta-carotene powder in capsule daily for six months, and Group II and IV received placebo in place of beta-carotene. Serum retinol and beta-carotene levels were measured before and after six months of the interventions. Serum retinol and beta-carotene increased significantly in Group I where both antihelminthic therapy and daily beta-carotene supplementation were given (p<0.05 and p<0.001 respectively). Antihelminthic therapy alone only improved serum beta-carotene concentration (p<0.0001). Low-dose beta-carotene supplementation, along with an antihelminthic therapy, synergistically improved vitamin A status. This finding has public-health implications for improving vitamin A status of children in developing countries.

Coverage of vitamin A capsule programme in Bangladesh and risk factors associated with non-receipt of vitamin A

Vitamin A supplementation reduces child morbidity, mortality, and blindness. The coverage of the national vitamin A programme and risk factors for not receiving vitamin A were characterized using data from the Bangladesh Demographic and Health Survey 2004. Of 3,745 children aged 18-59 months, 3,237 (86.4%) received a vitamin A capsule each within the last six months. Children who missed vitamin A were more likely to be stunted (prevalence ratio [PR] 0.97, 95% confidence interval [CI] 0.95-1.00) and come from a family with a previous history of mortality of children aged less than five years (PR 0.95, 95% CI 0.91-0.99). Maternal education of > or = 10 years (PR 1.09, 95% CI 1.04-1.13), 7-9 years (PR 1.08, 95% CI 1.04-1.12), and 1-6 years (PR 1.05, 95% CI 1.02-1.08) compared to no formal education was associated with the child not receiving vitamin A in a multivariate model, adjusting for potential confounders. Children missed by the vitamin A programme were more likely to come from families with lower maternal education. Special efforts are required to ensure that the coverage of the national vitamin A programme is increased further so that the most vulnerable children are also better protected against morbidity, mortality, and blindness.

Demographic and health-related risk factors of subclinical vitamin A deficiency in Ethiopia

The study was conducted to determine the demographic and health-related risk factors of subclinical vitamin A deficiency in Ethiopia. Blood samples were collected from 996 children in 210 clusters across the nation for analysis of serum retinol. Interviews were conducted with the respective mothers of the 996 children on presumed risk factors of vitamin A deficiency. A higher subclinical vitamin A deficiency was associated with: not receiving vitamin A supplement over the year, having been ill during the two weeks preceding the survey, no or incomplete vaccination, belonging to a mother with high parity, and low levels of awareness of vitamin A. Moreover, being from Muslim household was strongly associated with higher levels of subclinical vitamin A deficiency. Among the risk factors identified, low levels of vaccination, high parity, and low levels of maternal awareness of vitamin A contributed to higher risks of vitamin A deficiency among Muslim children. The findings underscore the need for creation of strengthened awareness of family planning and importance of vitamin A, promotion of vaccination and child health, intensification of vitamin A supplementation, and in-depth investigation on factors contributing to increased vulnerability of Muslim children.

Retinoids synergize with insulin to induce hepatic Gck expression

Hepatic GK (glucokinase) plays a key role in maintaining glucose homoeostasis. Many stimuli regulate GK activity by controlling its gene transcription. We hypothesized that endogenous lipophilic molecules modulate hepatic Gck expression. Lipophilic molecules were extracted from rat livers, saponified and re-constituted as an LE (lipophilic extract). LE synergized with insulin to induce primary hepatocyte, but not beta-cell, Gck expression in an SREBP-1c (sterol-regulatory-element-binding protein-1c)-independent manner. The dramatic induction of Gck mRNA resulted in a significant increase in GK activity. Subsequently, the active molecules were identified as retinol and retinal by MS after the purification of the active LE fractions. Retinoids synergized with insulin to induce Gck expression by the activation of both RAR [RA (retinoic acid) receptor] and RXR (retinoid X receptor). Inhibition of RAR activation completely abolished the effect of retinal. The hepatic GK specific activity and Gck mRNA levels of Zucker lean rats fed with a VAD [VA (vitamin A)-deficient] diet were significantly lower than those of rats fed with VAS (VA-sufficient) diet. Additionally, the hepatic Gck mRNA expression of Sprague-Dawley rats fed with a VAD diet was lower than that of rats fed with VA-marginal, -adequate or -supplemented diets. The reduced expression of Gck mRNA was increased after an intraperitoneal dose of RA in VAD rats. Furthermore, an intravenous injection of RA rapidly raised hepatic Gck expression in rats fed with a VAS control diet. Understanding the underlying mechanism that mediates the synergy may be helpful for developing a treatment strategy for patients with diabetes.

Micronutrients and anaemia

Micronutrient deficiencies and anaemia remain as major health concerns for children in Bangladesh. Among the micronutrient interventions, supplementation with vitamin A to children aged less than five years has been the most successful, especially after distribution of vitamin A was combined with National Immunization Days. Although salt sold in Bangladesh is intended to contain iodine, much of the salt does not contain iodine, and iodine deficiency continues to be common. Anaemia similarly is common among all population groups and has shown no sign of improvement even when iron-supplementation programmes have been attempted. It appears that many other causes contribute to anaemia in addition to iron deficiency. Zinc deficiency is a key micronutrient deficiency and is covered in a separate paper because of its importance among new child-health interventions.

Loss of ileal IgA+ plasma cells and of CD4+ lymphocytes in ileal Peyer's patches of vitamin A deficient rats

Child mortality in diarrhoeal disease is increased significantly by vitamin A deficiency in poor countries. The pathological mechanisms are not known in detail. However, in this paper we report that vitamin A-deficient Wistar rats had much reduced IgA+ plasma cells in the ileal lamina propria (eightfold reduction from 470 cells/mm(2), P = 0.009), as well as a prominent reduction of CD4+ cells in the parafollicular regions of ileal Peyer's patches (reduction from 7200 to 105 cells/mm(2), P = 0.009). IL-2Ralpha-chain (CD25) positive lymphocytes in the ileal Peyer's patches were also reduced significantly in vitamin A deficiency (from 1400 to 300 cells/mm(2), P = 0.009). The density of CD8 cells tended to be increased relative to the control animals (from 5100 to 6000 cells/mm(2), not statistically significant). In conclusion, the marked decrease of lamina propria IgA+ plasma cells may be one cause of the high diarrhoeal mortality in vitamin A deficiency. This, in turn, appears to be related to reduced numbers of activated or regulatory CD4+ T cells in Peyer's patches.

Early onset photoreceptor abnormalities induced by targeted disruption of the interphotoreceptor retinoid-binding protein gene

Vision in all vertebrates is dependent on an exchange of retinoids between the retinal pigment epithelium and the visual photoreceptors. It has been proposed that the interphotoreceptor retinoid-binding protein (IRBP) is essential for this intercellular exchange, and that it serves to prevent the potentially cytotoxic effects of retinoids. Although its precise function in vivo has yet to be defined, the early expression of IRBP suggests that it may also be required for normal photoreceptor development. To further assess the biological role of IRBP, we generated transgenic mice with targeted disruption of the IRBP gene (IRBP-/- mice). Specifically, homologous recombination was used to replace the first exon and promoter region of the IRBP gene with a phosphoglycerate kinase-promoted neomycin-resistant gene. Immunocytochemical and Western blot analyses demonstrated the absence of IRBP expression in the IRBP-/- mice. As early as postnatal day 11, histological examination of the retinas of IRBP-/- mice revealed a loss of photoreceptor nuclei and changes in the structural integrity of the receptor outer segments. At 30 d of age, the photoreceptor abnormalities in IRBP-/- mice were more severe, and electroretinographic recordings revealed a marked loss in photic sensitivity. In contrast, no morphological or electrophysiological changes were detected in age-matched heterozygotes. These observations indicate that normal photoreceptor development and function are highly dependent on the early expression of IRBP, and that in the absence of IRBP there is a slowly progressive degeneration of retinal photoreceptors.

In vivo growth and differentiation potential of tracheal basal cells of rabbits in vitamin A deficiency

The growth and differentiation potential of rabbit tracheal basal cells were investigated in vitamin A deficient mice. Denuded rat tracheal grafts were xenotransplanted into nude mice made vitamin A deficient by feeding them retinol-free pellets from mid-gestation. Rabbit tracheal epithelial cells harvested enzymatically or cells derived from a basal-cell-rich fraction obtained by elutriation (purity 93.3%) had previously been inoculated into the grafts (n = 8, each). The grafts were implanted into the vitamin A deficient or control mice aged about 10 weeks. Four weeks later, the grafts were retrieved for histological examination. The graft epithelium established by either basal cells or un-fractionated cells in vitamin A deficient hosts (groups 1 and 2, respectively) was atrophic, whereas grafts repopulated with both cell types in the controls had pseudostratified columnar epithelium. Group 1 and 2 grafts both showed squamous metaplasia; 10 metaplastic foci in 32 tracheal rings in group 1 (P < 0.02 or 0.002, compared with values for group 2 or controls, respectively), and 2 foci in 35 rings in group 2 (no statistical difference compared with controls). In conclusion, during vitamin A deficiency, rabbit tracheal epithelial cells, including the progeny of highly-purified basal cells, lost their potential for establishing a mucociliary epithelium and rather appeared to undergo squamous metaplasia.