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1.
J Zoo Wildl Med ; 55(1): 277-284, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38453512

RESUMEN

Two female (FL 1, FL 2) and one male (ML) 11-wk-old, intact, captive African lion cubs (Panthera leo leo) were presented with a history of mild vestibular signs. Initial serum vitamin A concentrations were low (140 nmol/L) for ML. Calvarial hyperostosis was confirmed using computed tomography (CT) of the head and cervical vertebrae in each cub. CT measurements were adapted in relation to the skull width. ML showed the most pronounced thickening of the tentorium cerebelli and occipital bone, represented by a tentorium cerebelli to skull width ratio (TCR) of 0.08 (FL 1: 0.06, FL 2: 0.05) and a basisphenoid to skull width ratio (BBR) of 0.07 (FL 1: 0.06, FL 2: 0.04). Magnetic resonance imaging (MRI) revealed cerebellar herniation and cervical intramedullary T2-weighted hyperintensity from C1, extending caudally for at least two cervical vertebrae in all cubs. Treatment was initiated with subcutaneous vitamin A supplementation and feeding of whole carcasses. Improvement in ataxia was noticed 3 wk later. Follow-up CT and MRI examinations were performed in ML after 3 and 8 mon. The affected bones appeared slightly less thickened and TCR and BBR had decreased to 0.05 after 3 mon. The cerebellum remained mildly herniated, accompanied by amelioration of cervical T2w hyperintensities. After 8 mon, evaluation and diagnostic imaging revealed further improvement regarding the neurologic status and measurements (TCR 0.05, BBR 0.04) despite persistence of a subtle cerebellar herniation. In conclusion, bone remodeling and improvement in clinical signs may be achievable in young lion cubs presented with calvarial hyperostosis and may be attributable to high-dose vitamin A supplementation.


Asunto(s)
Anomalías Craneofaciales , Hiperostosis , Leones , Deficiencia de Vitamina A , Masculino , Femenino , Animales , Vitamina A/uso terapéutico , Deficiencia de Vitamina A/veterinaria , Encefalocele/complicaciones , Encefalocele/tratamiento farmacológico , Encefalocele/veterinaria , Suplementos Dietéticos , Receptores de Antígenos de Linfocitos T
2.
Sci Rep ; 14(1): 4602, 2024 02 26.
Artículo en Inglés | MEDLINE | ID: mdl-38409312

RESUMEN

Promoting the intake of foods rich in vitamin A is key to combating the increase in vitamin A deficiency. This research focused on the utilization of orange-fleshed sweet potatoes (a tuber-based food), cowpea (a pulse), and ripe bananas (a fruit) for the production of flour mix as a means to reduce Vitamin A deficiency in children. Different ratios of sweet potato-cowpea-banana (PCB) mix, resulting in 8 different blended samples, were optimized. The flour mix was evaluated for its overall acceptability, vitamin A content, beta-carotene, and other nutritional and functional properties. The panelists rated the sweet potato-cowpea banana blends labeled PCB8 (60% OFSP, 30% cowpea, 5% ripe banana flour, and 5% sugar) as most preferred and acceptable with average scores of 8.96 points for color, 8.75 points for flavor, 8.88 points for appearance, 8.33 points for taste, 8.07 points for texture, and 8.39 points for overall acceptability on a 9-point hedonic scale. The vitamin A and beta-carotene contents ranged 7.62 to 8.35 mg/100 g and 0.15-0.17 mg/100 g for all blends. A significant difference in the functional properties of the flour mix were observed with an increase in the ratio of sweet potato flour addition. Findings from this study show that the flour mix PCB4 (65% sweet potato, 30% cowpea, and 5% ripe banana flour) was acceptable (8.15) and is recommended based on its vitamin A content (8.35 mg/100 g), nutritional properties, and functional properties. The study showed that locally available food commodities have good nutritional value that will help reduce vitamin A deficiency in children.


Asunto(s)
Citrus sinensis , Ipomoea batatas , Musa , Vigna , Deficiencia de Vitamina A , Niño , Humanos , Vitamina A , beta Caroteno , Harina
3.
Doc Ophthalmol ; 148(2): 121-128, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38265517

RESUMEN

PURPOSE: To report our findings of reduced full-field electroretinograms (ff-ERGs) and abnormal optical coherence tomographic (OCT) images in a patient with poor visual acuity after cataract surgery who was eventually diagnosed with vitamin A deficiency (VAD). METHODS: This was a clinical study of a patient who complained of blurred vision after cataract surgery. To determine the cause of the reduced vision, we recorded full-field electroretinograms (ff-ERGs) to determine the scotopic and photopic status of the retina. We also performed optical coherence tomography to assess the changes in the retinal structure. Serological tests were performed. RESULTS: A 74-year-old man presented with persistent corneal epithelial damages and reduced vision that developed after conventional cataract surgery. OCT showed an interrupted ellipsoid zone, and fundus autofluorescence (FAF) showed a severe hypofluorescence in the retina of the left eye. The scotopic ff-ERGs were severely reduced, and the photopic ff-ERGs were mildly reduced. Serological examinations revealed a vitamin A concentration < 7 IU/dL (normal, 97-316 IU/dL). Based on these findings, we diagnosed the patient with VAD and started treatment with oral vitamin A supplements. After three months, his visual acuity, ff-ERGs, and OCT findings recovered to normal levels. The amplitudes and implicit times of the RETeval flicker ERGs increased to be within the normal range, and the hypofluorescence of the left eye disappeared. The length of the photoreceptor outer segments increased after the vitamin A supplementation. CONCLUSION: Our findings indicate that the ERGs are helpful for diagnosing patients with VAD associated with persistent corneal epithelial damages.


Asunto(s)
Catarata , Baja Visión , Deficiencia de Vitamina A , Masculino , Humanos , Anciano , Electrorretinografía/métodos , Deficiencia de Vitamina A/diagnóstico , Deficiencia de Vitamina A/etiología , Vitamina A , Trastornos de la Visión/diagnóstico , Trastornos de la Visión/etiología , Tomografía de Coherencia Óptica/métodos
4.
Eur J Nutr ; 63(3): 905-918, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38240773

RESUMEN

PURPOSE: Vitamin A deficiency (VAD) remains a significant contributor to childhood morbidity and mortality in developing countries; therefore, the implementation of sustainable and cost-effective approaches to control VAD is of utmost pertinence. This study aims to investigate the efficacy of red palm olein (RPO)-enriched biscuit supplementation in improving vitamin A, haematological, iron, and inflammatory status among vitamin A-deficient schoolchildren. METHODS: We conducted a double-blinded, randomised controlled trial involving 651 rural primary schoolchildren (8-12 years) with VAD in Malaysia. The schoolchildren were randomised to receive either RPO-enriched biscuits (experimental group, n = 334) or palm olein-enriched biscuits (control group, n = 317) for 6-month duration. RESULTS: Significant improvements in retinol and retinol-binding protein 4 levels were observed in both groups after supplementation (P < 0.001). The improvement in retinol levels were similar across groups among subjects with confirmed VAD (P = 0.40). Among those with marginal VAD, greater improvement in retinol levels was recorded in the control group (P < 0.001) but lacked clinical significance. The levels of α- and ß-carotenes, haematological parameters (haemoglobin, packed cell volume, mean corpuscular volume and mean corpuscular haemoglobin) and iron enhanced more significantly in the experimental group (P < 0.05). The significant reduction in the prevalence of microcytic anaemia (- 21.8%) and high inflammation (- 8.1%) was only observed in the experimental group. CONCLUSION: The supplementation of RPO-enriched biscuits enhanced levels of provitamin A carotenes, iron, and erythropoiesis, and exhibited anti-inflammatory effects. Therefore, the incorporation of RPO into National Nutritional Intervention Programs may be a potential measure to improve the health status of vitamin A-deficient children, among various other interventions. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov (NCT03256123).


Asunto(s)
Deficiencia de Vitamina A , Vitamina A , Niño , Humanos , Carotenoides , Provitaminas , Hierro , Eritropoyesis , Deficiencia de Vitamina A/tratamiento farmacológico , Deficiencia de Vitamina A/epidemiología , Suplementos Dietéticos , Estado Nutricional
5.
J Pediatr ; 265: 113816, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37931699

RESUMEN

OBJECTIVES: To assess postmortem vitamin A (VA) concentrations in children under 5 years of age and evaluate the association between VA deficiency (VAD) and infectious causes of death (CoD). STUDY DESIGN: In this cross-sectional study from the Child Health and Mortality Prevention Surveillance (CHAMPS) Network, liver biopsies collected within 72 hours of death were analyzed from 405 stillbirths and children under 5 years in Kenya and South Africa. Total liver VA (TLVA) concentrations were quantified using ultra-performance liquid chromatography, and cutoffs of ≤0.1 µmol/g, >0.1 to <0.7 µmol/g, ≥0.7 to <1.0 µmol/g, and ≥1.0 µmol/g were used to define VAD, adequate VA status, high VA, and hypervitaminosis A, respectively. CoD were determined by expert panel review. RESULTS: Among 366 liver samples with viable extraction, pooled prevalences of VAD, adequacy, high VA, and hypervitaminosis were 34.2%, 51.1%, 6.0%, and 8.7%, respectively. VAD was more common among neonates compared with stillbirths, infants, or children, and among those with low birthweight (LBW), underweight, or stunting (P < .05). When adjusting for site, age, and sex, there was no significant association of VAD with increased infectious CoD (OR 1.9, 95% confidence interval [CI] 0.9, 3.8, P = .073). In stratified analyses, VA deficient boys, but not girls, had an increased risk of infectious CoD (OR 3.4, 95% CI 1.3, 10.3, P = .013). CONCLUSIONS: Definitive postmortem assessment of VA status identified both VAD and VA excess among children under 5 years of age in Kenya and South Africa. VAD in boys was associated with increased risk of infectious mortality. Our findings may inform a transition from universal VA supplementation (VAS) to targeted strategies in certain countries.


Asunto(s)
Enfermedades Transmisibles , Deficiencia de Vitamina A , Niño , Masculino , Lactante , Recién Nacido , Femenino , Embarazo , Humanos , Preescolar , Vitamina A/efectos adversos , Estudios Transversales , Mortinato , Deficiencia de Vitamina A/complicaciones , Deficiencia de Vitamina A/epidemiología , Vitaminas , Hígado
6.
Ophthalmol Retina ; 8(2): 126-136, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37673395

RESUMEN

PURPOSE: To explore the risk factors and fundus imaging features of vitamin A deficiency retinopathy (VADR) in an academic tertiary referral center in Atlanta, GA, United States, and to propose guidance regarding diagnostic workup and management of affected patients. DESIGN: Single-center retrospective case series. SUBJECTS: Nine patients seen between 2015 and 2021 at the Emory Eye Center diagnosed with VADR. METHODS: Retrospective chart review. MAIN OUTCOME MEASURES: Baseline serum retinol level, Snellen visual acuity, multimodal fundus imaging findings, and electroretinography findings. RESULTS: Nine patients, 4 (44.4%) female, with a median (range) age of 68 (50-75) years were identified. The most common underlying etiologies for vitamin A deficiency included history of gastrointestinal surgery (55.6%), liver disease (44.4%), and nutritional depletion due to low-quality diet (44.4%). Only 1 (11.1%) patient had a history of bariatric surgery. Four (44.4%) patients were on some form of vitamin A supplementation before the diagnosis of VADR. Median (range) serum retinol level was 0.06 (< 0.06-0.19) mg/L. All patients had macular subretinal hyperreflective deposits resembling subretinal drusenoid deposits, although in some cases, these were scant and sparsely distributed. Six eyes of 3 patients with longstanding deficiency had defects in the external limiting membrane (ELM). Three of these eyes additionally had macular areas of complete retinal pigment epithelium and outer retinal atrophy (cRORA). Full-field electroretinography demonstrated severe rod dysfunction and mild to moderate cone system dysfunction. Many findings of VADR were reversible with vitamin A repletion. However, all eyes with ELM defects or cRORA had persistence or continued growth of these lesions. CONCLUSION: Vitamin A deficiency retinopathy is uncommon in the developed world. However, given that early intervention can lead to dramatic visual improvement and avoid potentially permanent retinal damage, retina specialists should be familiar with its clinical presentation. The presence of nyctalopia and subretinal hyperreflective deposits in a patient with a history of gastrointestinal surgery, liver disease, and/or poor diet can be suggestive of this diagnosis, even in the presence of ongoing vitamin A supplementation. Vitamin A supplementation can vary in route and dosage and can be tailored to the individual with serial testing of serum retinol. FINANCIAL DISCLOSURE(S): The authors have no proprietary or commercial interest in any materials discussed in this article.


Asunto(s)
Hepatopatías , Degeneración Retiniana , Deficiencia de Vitamina A , Humanos , Femenino , Estados Unidos/epidemiología , Anciano , Masculino , Vitamina A , Deficiencia de Vitamina A/complicaciones , Deficiencia de Vitamina A/diagnóstico , Estudios Retrospectivos , Centros de Atención Terciaria , Angiografía con Fluoresceína/métodos
8.
Nutr Clin Pract ; 39(2): 373-384, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38030585

RESUMEN

Vitamin A imbalance during pregnancy and lactation is a global public health concern with potentially negative consequences for fetuses and neonates. Inadequate vitamin A intake during this critical period can lead to anemia, weakened immune function, night blindness, and increased susceptibility to infections. Conversely, excessive intake of vitamin A can result in birth defects, hypercalcemia, and psychiatric symptoms. This review aims to identify risk factors contributing to vitamin A deficiency in pregnant women and its impact on maternal, fetal, and neonatal outcomes. It also examines the effects of high-dose vitamin A supplementation during pregnancy on offspring health. By analyzing existing literature and recommendations, the review emphasizes the significance of vitamin A in the development of various body systems and organs. It provides a comprehensive overview of the effects of vitamin A during pregnancy and lactation, encompassing deficiencies, excessive intake, and supplementation guidelines. The need for further research in this field is highlighted. In conclusion, maintaining a balanced vitamin A status is crucial during pregnancy to promote better outcomes for fetuses and newborns. Effective monitoring and intervention strategies are essential to address vitamin A deficiency and excess in pregnant women, thereby improving fetal and neonatal health.


Asunto(s)
Complicaciones del Embarazo , Deficiencia de Vitamina A , Deficiencia de Vitamina D , Recién Nacido , Femenino , Embarazo , Humanos , Vitamina A/uso terapéutico , Vitaminas/uso terapéutico , Deficiencia de Vitamina A/tratamiento farmacológico , Deficiencia de Vitamina A/epidemiología , Complicaciones del Embarazo/epidemiología , Lactancia , Suplementos Dietéticos
9.
Nutrients ; 15(24)2023 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-38140394

RESUMEN

This systematic review aims to assess whether edible vegetable oils and fats fortified with vitamin A and/or D are effective and safe in improving vitamin intake and ameliorating deficiency states in the general population. In November 2022, we systematically searched MEDLINE, Cochrane CENTRAL, Scopus, Global Index Medicus, ClinicalTrials.gov, and WHO ICTRP (International Clinical Trials Registry Platform) for randomized controlled trials (RCT) and non-randomized studies of interventions (NRSI) investigating the fortification of edible vegetable oils and fats with either vitamin A or vitamin D or both as compared to the same vegetable oils and/or fats without vitamin A and D fortification or no interventions, in the general population, without age restriction. We assessed the methodological quality of included RCTs using Cochrane's risk of bias tool 2.0 and of NRSIs using ROBINS-I tool. We performed random-effects meta-analysis and assessed certainty of evidence using GRADE. We included eight studies. Available evidence showed no significant effect of fortification with vitamin A on serum retinol levels (RCTs: MD 0.35 µmol/L, 95% CI -0.43 to 1.12; two trials; 514 participants; low-certainty evidence; CCTs: MD 0.31 µmol/L, 95% CI -0.18 to 0.80; two trials; 205 participants; very low-certainty evidence) and on subclinical vitamin A deficiency. Low-certainty evidence showed no effect of vitamin D fortification on serum 25-hydroxy vitamin D concentration (MD 6.59 nmol/L, 95% CI -6.89 to 20.07; one trial; 62 participants). In conclusion, vitamin A-fortified vegetable oils and fats may result in little to no difference in serum retinol levels in general populations. The dose of vitamin A used in the trials may be safe but may not be sufficient to reduce subclinical vitamin A deficiency. Further, the evidence suggests that vitamin D fortification results in little to no difference in serum 25-hydroxy vitamin D concentration. Several aspects of providing fortified oils and fats to the general population as a public health intervention should be further investigated, including optimal fortification dose, effects on vitamin D deficiency and its clinical symptoms and potential adverse effects.


Asunto(s)
Deficiencia de Vitamina A , Vitaminas , Humanos , Vitamina A/efectos adversos , Deficiencia de Vitamina A/epidemiología , Deficiencia de Vitamina A/prevención & control , Verduras , Salud Pública , Aceites de Plantas/efectos adversos , Alimentos Fortificados , Vitamina K , Vitamina D
10.
BMJ Open Ophthalmol ; 8(Suppl 3): A3, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37797989

RESUMEN

A 12-year-old boy presented with 5 day history of blurry vision, 'wobbly eyes', tinnitus and difficulty seeing at night. Local ophthalmology noted bilateral optic disc swelling and referred him urgently for neurological investigations.Clinical Findings: At presentation VA was RE 0.00 and LE 0.2 with normal Ishihara colour vision. His extraocular movements were full without manifest strabismus. Fundoscopy showed bilateral optic disc swelling. Electrophysiology unexpectedly revealed a functionally cone isolated retina with markedly abnormal rod function. Pattern VEPs indicated bilateral macular pathway dysfunction affecting left eye more than right eye. Wide field imaging showed bilateral diffusely scattered yellow-white flecks in the midperiphery of each eye. His kinetic visual fields were moderately restricted bilaterally. MRI showed a Chiari 1 malformation with cerebellar tonsil herniation, but LP opening pressure was normal.Differential diagnosis included RDH5 retinopathy or vitamin A deficiency. On questioning he reported a diet restricted to only meat and biscuits. His vitamin A levels were subnormal at 0.14 umol/L (reference range 0.9-2.5umol/l) and he was started on high-dose Vitamin A supplements.Four months after supplementation retinal appearances had normalised, the rod ERGs recovered, nyctalopia and visual field restriction resolved. PVEPs had improved but an element of LE macular pathway dysfunction remained. Optic disc swelling settled leaving mild temporal pallor, particularly of the LE with some RNFL loss.It is important to recognise nutritional Vitamin A deficiency in children as prompt recognition and treatment can improve symptoms, reverse retinal pathology which we have demonstrated with electrophysiological findings.


Asunto(s)
Disco Óptico , Papiledema , Enfermedades de la Retina , Deficiencia de Vitamina A , Humanos , Masculino , Niño , Disco Óptico/patología , Vitamina A , Deficiencia de Vitamina A/patología , Retina/patología , Enfermedades de la Retina/patología , Papiledema/patología , Trastornos de la Visión/diagnóstico
11.
J Nutr Sci Vitaminol (Tokyo) ; 69(3): 157-163, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37394420

RESUMEN

Childhood obesity has become a public health concern. As the importance of vitamin A (VA) in the body has become increasingly acknowledged, there is limited clinical trial evidence to substantiate the association between VA and childhood obesity. Vitamin A deficiency (VAD) increases the risk of childhood obesity, a finding consistently reported in pregnant women. VA could regulate the adipogenic process, inflammation, oxidative stress and metabolism-related gene expression in mature adipocytes. VAD disrupts the balance of obesity-related metabolism, thus affecting lipid metabolism and insulin regulation. Conversely, VA supplementation has a major impact on efficacy in obesity, and obese individuals typically have a lower VA status than normal-weight individuals. Several studies have attempted to identify the genetic and molecular mechanisms underlying the association between VA and obesity. In this review, we summarize and discuss recent new developments focusing on retinol, retinoic acid, and RBP4 and elucidate and provide an overview of the complex interrelationships between these critical components of VA and childhood obesity. However, the causal relationship between VA status and childhood obesity remains unclear. It is also unknown whether VA supplementation improves the overall obesogenic metabolic profile.


Asunto(s)
Obesidad Infantil , Deficiencia de Vitamina A , Embarazo , Humanos , Niño , Femenino , Vitamina A , Deficiencia de Vitamina A/complicaciones , Tretinoina , Insulina/metabolismo , Proteínas Plasmáticas de Unión al Retinol/metabolismo
12.
J AAPOS ; 27(4): 198.e1-198.e4, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37453663

RESUMEN

BACKGROUND: Vitamin A is vital to retinal rod function and epithelial cell differentiation. Although uncommon in the developed world, vitamin A deficiency (VAD) secondary to poor diets or gastrointestinal disease has been reported and can lead to xerophthalmia, which is characterized by night blindness and a spectrum of ocular surface changes. Patients with autism spectrum disorder have been shown to have restrictive diets secondary to sensory issues leading to rejection of foods except for those of certain color or texture. METHODS: We present a case series of 6 pediatric patients with autism who developed varying degrees of xerophthalmia due to VAD, which resulted from restrictive eating. RESULTS: All patients presented with a history of eye irritation that was not relieved by antibiotic or allergy eye drops. Further questioning revealed they had restrictive diets consisting of only or mostly white and tan foods, and serum vitamin A testing confirmed severe VAD. Most stages of xerophthalmia were completely reversed with vitamin A supplementation, but in 2 patients more advanced xerophthalmia resulted in irreversible blindness and ocular damage. CONCLUSIONS: Both pediatricians and pediatric eye care providers must be vigilant for VAD as an etiology of eye irritation, photophobia, or new-onset visual impairment in autistic children. A review of the child's diet must be implemented as a standard part of routine history taken in this vulnerable population. Early identification and vitamin A supplementation can prevent irreversible ocular compromise and vision loss.


Asunto(s)
Trastorno del Espectro Autista , Trastorno Autístico , Deficiencia de Vitamina A , Xeroftalmia , Niño , Humanos , Trastorno del Espectro Autista/complicaciones , Trastorno Autístico/complicaciones , Ceguera/etiología , Ceguera/epidemiología , Vitamina A , Deficiencia de Vitamina A/complicaciones , Deficiencia de Vitamina A/epidemiología , Xeroftalmia/etiología , Xeroftalmia/epidemiología
13.
J Nutr ; 153(9): 2762-2771, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37468045

RESUMEN

BACKGROUND: Suboptimal plasma retinol concentrations have been documented in US children with sickle cell disease (SCD) hemoglobin SS type (SCD-HbSS), but little is known about vitamin A kinetics and stores in SCD. OBJECTIVES: The objectives were to quantify vitamin A total body stores (TBS) and whole-body retinol kinetics in young people with SCD-HbSS and use retinol isotope dilution (RID) to predict TBS in SCD-HbSS and healthy peers as well as after vitamin A supplementation in SCD-HbSS subjects. METHODS: Composite plasma [13C10]retinol response data collected from 22 subjects with SCD-HbSS for 28 d after isotope ingestion were analyzed using population-based compartmental modeling ("super-subject" approach); TBS and retinol kinetics were quantified for the group. TBS was also calculated for the same individuals using RID, as well as for healthy peers (n = 20) and for the subjects with SCD-HbSS after 8 wk of daily vitamin A supplements (3.15 or 6.29 µmol retinol/d [900 or 1800 µg retinol activity equivalents/d]). RESULTS: Model-predicted group mean TBS for subjects with SCD-HbSS was 428 µmol, equivalent to ∼11 mo of stored vitamin A; vitamin A disposal rate was 1.3 µmol/d. Model-predicted TBS was similar to that predicted by RID at 3 d postdosing (mean, 389 µmol; ∼0.3 µmol/g liver); TBS predictions at 3 compared with 28 d were not significantly different. Mean TBS in healthy peers was similar (406 µmol). RID-predicted TBS for subjects with SCD-HbSS was not significantly affected by vitamin A supplementation at either dose. CONCLUSIONS: Despite differences in plasma retinol concentrations, TBS was the same in subjects with SCD-HbSS compared with healthy peers. Because 56 d of vitamin A supplementation at levels 1.2 to 2.6 times the Recommended Dietary Allowance did not increase TBS in these subjects with SCD-HbSS, further work will be needed to understand the effects of SCD on retinol metabolism. This trial was registered as NCT03632876 at clinicaltrials.gov.


Asunto(s)
Anemia de Células Falciformes , Deficiencia de Vitamina A , Niño , Humanos , Adolescente , Vitamina A , Suplementos Dietéticos , Isótopos
14.
J Nutr ; 153(8): 2523-2530, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37380059

RESUMEN

BACKGROUND: Although the vitamin A (VA) equivalency of provitamin A carotenoids from single foods or capsules has been studied using several approaches, there is currently no reliable method to determine VA equivalency for mixed diets. OBJECTIVES: To reach the objective of identifying a method to determine the VA equivalency of provitamin A carotenoids in mixed diets, we tested a new approach using preformed VA as proxy for provitamin A. METHODS: We studied 6 theoretical subjects who were assigned physiologically plausible values for dietary VA intake, retinol kinetic parameters, plasma retinol pool size, and VA total body stores. Using features in the Simulation, Analysis and Modeling software, we specified that subjects ingested a tracer dose of stable isotope-labeled VA on day 0 followed by 0-µg supplemental VA or 200, 400, 800, 1200, 1600, and 2000 µg VA daily from day 14 to day 28; we assigned VA absorption to be 75%. For each supplement level, we simulated plasma retinol specific activity (SAp) over time and calculated the mean decrease in SAp relative to 0 µg. Group mean data were fitted to a regression equation to calculate predicted VA equivalency at each supplement level on day 28. RESULTS: For each subject, higher VA supplement loads resulted in lower SAp, with the magnitude of the decrease differing among subjects. The mean predicted amount of absorbed VA was within 25% of individual subjects' assigned amount for 4 of the 6 subjects, and the mean ratio of predicted to assigned amount of absorbed VA over all supplement loads ranged from 0.60 to 1.50, with an overall mean ratio of 1.0. CONCLUSIONS: Results for preformed VA suggest that this protocol may be useful for determining VA equivalency of provitamin A carotenoids in free-living subjects if mixed diets with known provitamin A content were substituted for the VA supplements.


Asunto(s)
Deficiencia de Vitamina A , Vitamina A , Humanos , Provitaminas/análisis , Dieta , Deficiencia de Vitamina A/prevención & control , Carotenoides , Suplementos Dietéticos/análisis
15.
Ophthalmic Surg Lasers Imaging Retina ; 54(6): 330-336, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37352397

RESUMEN

OBJECTIVES: To describe multimodal imaging findings of vitamin A deficiency retinopathy. METHODS: A retrospective study of patients with serum retinol < 0.3 mg/L. Fundus color photos, spectral domain-optical coherence tomography (SD-OCT), and fundus autofluorescence (FAF) were reviewed and, when available, electrophysiological tests were analyzed. RESULTS: Forty-five eyes (63.9 ± 15.7 years) were included. Ultra-widefield fundus photography showed drusen-like deposits (53.3%) and macular retinal pigment epithelium (RPE) mottling (40%). The deposits were hypoautofluorescent, and a perifoveal hyperautofluorescent ring was present in 8.9%. By SD-OCT, the ellipsoid zone had an irregular appearance (100%) and conical deposits anterior to the RPE (33.3%). Electroretinogram (ERG) (66.7%) showed a decrease in b-wave in the scotopic registers, and microperimetry (4.4%) showed decreased foveal sensitivity. After vitamin A supplementation, SD-OCT and FAF showed resolution of all findings. Forty percent of eyes had restoration of the scotopic registers in ERG and improved macular sensitivity by microperimetry (4.4%). CONCLUSIONS: Vitamin A deficiency causes a mild cone dysfunction in addition to the more severe absent rod response. [Ophthalmic Surg Lasers Imaging Retina 2023;54:330-336.].


Asunto(s)
Enfermedades de la Retina , Deficiencia de Vitamina A , Humanos , Deficiencia de Vitamina A/complicaciones , Deficiencia de Vitamina A/diagnóstico , Estudios Retrospectivos , Retina , Trastornos de la Visión , Tomografía de Coherencia Óptica , Imagen Multimodal , Angiografía con Fluoresceína
16.
Matern Child Health J ; 27(7): 1284-1292, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37166572

RESUMEN

OBJECTIVES: In Africa and Asia, 190 million preschoolers are vitamin A deficient. This study examined the social determinants of intake of vitamin A supplementation (VAS) among children aged 6-59 months during three different time periods in Kenya to identify those most vulnerable to vitamin A deficiency and highlight the varied targeting and outreach efforts; before the onset of a national restructuring and targeted distribution of VAS in children below 5 years through a twice-yearly door-to-door campaign called Child Health Weeks, during the implementation period, and several years later. METHODS: The cross-sectional, national Demographic and Health Surveys were administered in Kenya in 2003, 2008-09, and 2014. Bivariate and multivariable logistic regression analyses were used to assess variables associated with VAS among children (n = 28,239). RESULTS: An overall two-fold increase in VAS was recorded between 2003 (31.8%) and 2014 (67.5%). In 2008-09, children aged 6-11 months were the most likely to receive VAS. In 2003 and 2014, geographical regions and settings, birth order of the child, educational level of the mother, religion, wealth index, number of antenatal visits, and access to a radio were identified as being significantly associated with VAS, in at least one of the years. These determinants were not significant in 2008-09 during the initial Child Health Weeks promotion campaign. The determinants of VAS varied during the three study periods, particularly in 2008-09 when the Child Health Weeks was first implemented. CONCLUSION: As efforts to increase VAS continue, addressing child-specific determinants will be essential to reduce health disparities.


Asunto(s)
Deficiencia de Vitamina A , Vitamina A , Embarazo , Humanos , Femenino , Lactante , Kenia/epidemiología , Estudios Transversales , Determinantes Sociales de la Salud , Suplementos Dietéticos , Deficiencia de Vitamina A/epidemiología , Deficiencia de Vitamina A/prevención & control
17.
Adv Exp Med Biol ; 1436: 153-166, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37253944

RESUMEN

Mucormycosis is a rare but serious opportunistic fungal disease characterized by rhino-orbito-cerebral and pulmonary involvement. It is mainly seen in people with secondary immunosuppression, isolated vitamin A deficiency, measles, and AIDS patients. It showed a rise during the second wave of the COVID-19 epidemic in the spring of 2021 in India, especially in diabetic COVID-19 patients. Vitamin A deficiency is known to cause nutritional immunodeficiency and hence leading the way to increased opportunistic fungal, bacterial, and viral infections. In the eye, it causes keratitis, night blindness, xerophthalmia, conjunctivitis, Bitot spots, keratomalacia, and retinopathy. It also causes decreased tear secretion and deterioration of the anatomical/physiological defense barrier of the eye. The negative impact of vitamin A deficiency has been previously demonstrated in measles, AIDS, and COVID-19. We think that mucormycosis in COVID-19 might be rendered by vitamin A deficiency and that vitamin A supplementation may have preventive and therapeutic values against mucormycosis and other ocular symptoms associated with COVID-19. However, any vitamin A treatment regimen needs to be based on laboratory and clinical data and supervised by medical professionals.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida , COVID-19 , Oftalmopatías , Mucormicosis , Deficiencia de Vitamina A , Humanos , Mucormicosis/epidemiología , Deficiencia de Vitamina A/complicaciones , Vitamina A/uso terapéutico , Hongos
18.
Front Immunol ; 14: 1188757, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37180172

RESUMEN

Rotavirus A (RVA) causes ~200,000 diarrheal deaths annually in children <5yrs, mostly in low- and middle-income countries. Risk factors include nutritional status, social factors, breastfeeding status, and immunodeficiency. We evaluated the effects of vitamin A (VA) deficiency/VA supplementation and RVA exposure (anamnestic) on innate and T cell immune responses in RVA seropositive pregnant and lactating sows and passive protection of their piglets post-RVA challenge. Sows were fed VA deficient (VAD) or sufficient (VAS) diets starting at gestation day (GD)30. A subset of VAD sows received VA supplementation from GD|76 (30,000IU/day, VAD+VA). Sows (6 groups) were inoculated with porcine RVA G5P[7] (OSU strain) or Minimal Essential Medium (mock) at GD~90: VAD+RVA; VAS+RVA; VAD+VA+RVA; VAD-mock; VAS-mock; and VAD+VA-mock. Blood, milk, and gut-associated tissues were collected from sows at several time points to examine innate [natural killer (NK), dendritic (DC) cells], T cell responses and changes in genes involved in the gut-mammary gland (MG)-immunological axis trafficking. Clinical signs of RVA were evaluated post inoculation of sows and post-challenge of piglets. We observed decreased frequencies of NK cells, total and MHCII+ plasmacytoid DCs, conventional DCs, CD103+ DCs and CD4+/CD8+ and T regulatory cells (Tregs) and NK cell activity in VAD+RVA sows. Polymeric Ig receptor and retinoic acid receptor alpha (RARα) genes were downregulated in mesenteric lymph nodes and ileum of VAD+RVA sows. Interestingly, RVA-specific IFN-γ producing CD4+/CD8+ T cells were increased in VAD-Mock sows, coinciding with increased IL-22 suggesting inflammation in these sows. VA supplementation to VAD+RVA sows restored frequencies of NK cells and pDCs, and NK activity, but not tissue cDCs and blood Tregs. In conclusion, similar to our recent observations of decreased B cell responses in VAD sows that led to decreased passive immune protection of their piglets, VAD impaired innate and T cell responses in sows, while VA supplementation to VAD sows restored some, but not all responses. Our data reiterate the importance of maintaining adequate VA levels and RVA immunization in pregnant and lactating mothers to achieve optimal immune responses, efficient function of the gut-MG-immune cell-axis and to improve passive protection of their piglets.


Asunto(s)
Infecciones por Rotavirus , Rotavirus , Deficiencia de Vitamina A , Embarazo , Porcinos , Animales , Femenino , Vitamina A/farmacología , Linfocitos T CD8-positivos/metabolismo , Lactancia , Suplementos Dietéticos , Inmunidad
19.
BMC Pediatr ; 23(1): 257, 2023 05 23.
Artículo en Inglés | MEDLINE | ID: mdl-37221505

RESUMEN

BACKGROUND: Vitamin A deficiency is one of the major public health problems in low and middle-income countries including Ethiopia. Despite this fact, little attention was given to routine vitamin A supplementation in hard-to-reach rural areas and districts. Therefore, this study aimed to assess vitamin A supplementation coverage and its associated factors among children aged 6-59 months in West Azernet Berbere woreda, southern Ethiopia, 2021. METHODS: A community-based cross-sectional study was conducted from April to May 2021. A total sample size of 471 study participants was involved in the study area. A simple random sampling technique was used to recruit the study subject. A pretested structured interviewer-administered questionnaire was used. Bivariable and multivariable logistic regression analyses were done to identify variables having a significant association with vitamin A supplementation. The variables having a p-value ≤ 0.05 with 95% CI were used to declare an association between factors and a dependent variable. RESULTS: In this study, a total of 471 respondents were successfully interviewed with a response rate of 97.3%. The coverage of vitamin A supplementation was found to be 58.0%. Family monthly income [AOR = 2.565, 95% CI(1.631,4.032)], having PNC visit [AOR = 1.801, 95% CI (1.158, 2.801)], husbands disapproval about vitamin A supplementation [AOR = 0.324, 95% CI (0.129, 0.813)], information about vitamin A supplementation [AOR = 2.932, 95% CI (1.893, 4,542)] and ANC follow-up [AOR = 1.882, 95% CI (1.084, 3.266)] were factors significantly associated to vitamin A supplementation. CONCLUSION: Vitamin A supplementation was found to be low and it is strongly associated with family monthly income, postnatal care, husband's disapproval of vitamin A supplementation, antenatal care follow-up, and information about vitamin A supplementation. Based on our findings, it is recommended to improve the monthly income of the household by actively engaging in various income-generating activities, enhance health information dissemination among mothers, particularly those who are underprivileged by using different strategies like local health campaigns, and mass media, advocacy of antenatal, and postnatal follow-up and promote the involvement of males/husband in childhood immunization service.


Asunto(s)
Deficiencia de Vitamina A , Vitamina A , Niño , Femenino , Humanos , Masculino , Embarazo , Estudios Transversales , Suplementos Dietéticos , Etiopía/epidemiología , Vitamina A/administración & dosificación , Deficiencia de Vitamina A/epidemiología , Deficiencia de Vitamina A/prevención & control
20.
BMJ Open ; 13(3): e062387, 2023 03 14.
Artículo en Inglés | MEDLINE | ID: mdl-36918231

RESUMEN

OBJECTIVES: Vitamin A deficiency affects an estimated 29% of all children under 5 years of age in low/middle-income countries, contributing to child mortality and exacerbating severity of infections. Biannual vitamin A supplementation (VAS) for children aged 6-59 months can be a low-cost intervention to meet vitamin A needs. This study aimed to present a framework for evaluating the equity dimensions of national VAS programmes according to determinants known to affect child nutrition and assist programming by highlighting geographical variation in coverage. METHODS: We used open-source data from the Demographic and Health Survey for 49 countries to identify differences in VAS coverage between subpopulations characterised by various immediate, underlying and enabling determinants of vitamin A status and geographically. This included recent consumption of vitamin A-rich foods, access to health systems and services, administrative region of the country, place of residence (rural vs urban), socioeconomic position, caregiver educational attainment and caregiver empowerment. RESULTS: Children who did not recently consume vitamin A-rich foods and who had poorer access to health systems and services were less likely to receive VAS in most countries despite potentially having a greater vitamin A need. Differences in coverage were also observed when disaggregated by administrative regions (88% of countries) and urban versus rural residence (35% of countries). Differences in vitamin A coverage between subpopulations characterised by other determinants of vitamin A status varied considerably between countries. CONCLUSION: VAS programmes are unable to reach all eligible infants and children, and subpopulation differences in VAS coverage characterised by various determinants of vitamin A status suggest that VAS programmes may not be operating equitably in many countries.


Asunto(s)
Deficiencia de Vitamina A , Vitamina A , Humanos , Lactante , Niño , Preescolar , Vitamina A/uso terapéutico , Deficiencia de Vitamina A/epidemiología , Deficiencia de Vitamina A/prevención & control , Escolaridad , Mortalidad del Niño , Suplementos Dietéticos , Encuestas Epidemiológicas , Factores Socioeconómicos
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