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1.
BMJ Case Rep ; 15(3)2022 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-35351751

RESUMEN

Two male patients with known systemic disorders who presented with complaints of nyctalopia underwent a complete ophthalmic examination including electrophysiological evaluation and serum vitamin A (retinol) levels. A significant vitamin A deficiency was detected, supplementation started and repeat electroretinogram (ERG) testing was carried out to monitor the timeline of recovery. Restoration of rod and generalised cone function was rapid within the first week of receiving treatment and near normal recovery was seen after 1 month of supplementation. Serial monitoring of ERG changes in vitamin A deficiency (VAD) associated night blindness plays an important role to demonstrate functional recovery post-treatment. The different effects of VAD on rod and cone function, and their rate of recovery, may reflect differences in the visual cycle between the two photoreceptors. We report the serial ERG changes in VAD related night blindness secondary to intestinal lipofuscinosis and liver cirrhosis in two patients.


Asunto(s)
Ceguera Nocturna , Deficiencia de Vitamina A , Electrorretinografía , Humanos , Masculino , Ceguera Nocturna/tratamiento farmacológico , Ceguera Nocturna/etiología , Vitamina A/uso terapéutico , Deficiencia de Vitamina A/complicaciones , Deficiencia de Vitamina A/tratamiento farmacológico
2.
Optom Vis Sci ; 96(6): 453-458, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31107845

RESUMEN

SIGNIFICANCE: Vitamin A deficiency is a known concern in developing countries, but it is often overlooked in developed regions. A history of conditions causing alimentary malabsorption should be considered when patients present with complaints of nyctalopia. PURPOSE: A case of vitamin A deficiency with nyctalopia in a patient with chronic pancreatitis including pertinent diagnostic testing, treatment, and management is presented. The intent is to draw attention to the condition as a differential diagnosis for nyctalopia due to increased prevalence of conditions causing malabsorption. CASE REPORT: A patient with a history of chronic pancreatitis and pancreatic tumor presented with symptoms of nyctalopia and xerophthalmia. Given his systemic history, testing was ordered to determine serum vitamin A levels and retinal function. After results had confirmed depleted vitamin A levels and diminished retinal function, treatment with both oral and intramuscular vitamin A supplementation was initiated to normalize vitamin A levels and improve retinal photoreceptor function. Subjective improvement in symptoms was reported shortly after beginning supplementation, and ultimately, vitamin A levels and retinal function showed improvement after intramuscular treatment. CONCLUSIONS: Detailed case history and a careful review of systems along with serum vitamin A testing and, if available, electroretinography to assess retinal function can help to make a definitive diagnosis. With appropriate comanagement with the patient's primary care physician, it is possible for those with nyctalopia to begin vitamin A supplementation and regain retinal function.


Asunto(s)
Ceguera Nocturna/diagnóstico , Pancreatitis Crónica/diagnóstico , Deficiencia de Vitamina A/diagnóstico , Vitamina A/administración & dosificación , Administración Oral , Diagnóstico Diferencial , Suplementos Dietéticos , Electrorretinografía , Humanos , Masculino , Persona de Mediana Edad , Ceguera Nocturna/tratamiento farmacológico , Ceguera Nocturna/fisiopatología , Pancreatitis Crónica/fisiopatología , Células Fotorreceptoras de Vertebrados , Retina/fisiopatología , Vitamina A/sangre , Deficiencia de Vitamina A/tratamiento farmacológico , Deficiencia de Vitamina A/fisiopatología , Xeroftalmia/diagnóstico
3.
Optom Vis Sci ; 96(3): 227-232, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30801499

RESUMEN

SIGNIFICANCE: Although rare, vitamin A retinopathy should be considered by the clinicians in their differentials for conditions that can lead to nyctalopia, especially in those patients who have undergone bariatric surgery. Patients must be educated on this potential delayed adverse effect of the surgery and possible lifelong vitamin A supplementation. PURPOSE: The purpose of this study was to report a rare case of delayed vitamin A retinopathy that occurred because of vitamin A malabsorption secondary to bariatric surgery. CASE REPORT: A 55-year-old woman presented with nyctalopia and dark adaptation problems. The patient had a history of gastric bypass surgery 22 years earlier. Fundus examination revealed a large number of small white dots in the midperiphery of both eyes. Electrophysiology testing revealed flat-lined scotopic responses. Vitamin A levels were found to be severely reduced. Subsequent vitamin A supplementation resulted in the reversal of all signs and symptoms. CONCLUSIONS: This case report demonstrates the importance of considering vitamin A deficiency in patients who present with symptoms of nyctalopia with a history of bariatric surgery. Clinicians should be aware of a possible delayed onset and refer for appropriate testing and treatment, as vitamin A retinopathy has been shown to be reversible. Because other conditions can present with nyctalopia and retinal white spots, clinicians also need to consider the appropriate differential diagnoses. Lifelong monitoring is indicated because reoccurrences have been reported.


Asunto(s)
Cirugía Bariátrica/efectos adversos , Enfermedades de la Retina/etiología , Deficiencia de Vitamina A/etiología , Vitamina A/administración & dosificación , Suplementos Dietéticos , Femenino , Humanos , Persona de Mediana Edad , Ceguera Nocturna/diagnóstico , Ceguera Nocturna/tratamiento farmacológico , Ceguera Nocturna/etiología , Enfermedades de la Retina/diagnóstico , Enfermedades de la Retina/tratamiento farmacológico , Deficiencia de Vitamina A/diagnóstico , Deficiencia de Vitamina A/tratamiento farmacológico
4.
Doc Ophthalmol ; 132(2): 137-45, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26980447

RESUMEN

PURPOSE: To report treatment of vitamin A deficiency retinopathy with sublingual vitamin A drops. METHODS: Case report with review of the literature. RESULTS: A 69-year-old Caucasian woman with a history of small bowel resection presented with progressive symptoms of bilateral nyctalopia and decreased visual acuity. Ophthalmic examination revealed bilateral conjunctival xerosis and fine white granular deposits in the midperipheral retina suggestive of vitamin A deficiency. Full-field electroretinogram (ERG), multifocal ERG (mfERG), and two-color dark adaptometry revealed significant impairment of rod and cone photoreceptor function. Kinetic perimetry demonstrated depressed macular sensitivity with constriction of the finer isopters. After 5 months of treatment with sublingual vitamin A drops, the patient's vision, ERG, mfERG, dark adaptometry, and perimetry normalized. A review of the literature summarizing the electrophysiologic testing in vitamin A deficiency is also discussed. CONCLUSIONS: This case highlights novel observations on the effects of sublingual vitamin A supplementation for acquired vitamin A deficiency retinopathy. Sublingual vitamin A may represent a viable and efficacious treatment modality for vitamin A deficiency.


Asunto(s)
Ceguera Nocturna/tratamiento farmacológico , Retina/fisiopatología , Deficiencia de Vitamina A/tratamiento farmacológico , Vitamina A/análogos & derivados , Administración Sublingual , Anciano , Diterpenos , Electrorretinografía , Femenino , Humanos , Ceguera Nocturna/fisiopatología , Ésteres de Retinilo , Agudeza Visual/fisiología , Pruebas del Campo Visual , Campos Visuales/fisiología , Vitamina A/administración & dosificación , Vitamina A/sangre , Deficiencia de Vitamina A/fisiopatología
5.
Cochrane Database Syst Rev ; (10): CD008666, 2015 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-26503498

RESUMEN

BACKGROUND: The World Health Organization recommends routine vitamin A supplementation during pregnancy or lactation in areas with endemic vitamin A deficiency (where night blindness occurs), based on the expectation that supplementation will improve maternal and newborn outcomes including mortality, morbidity and prevention of anaemia or infection.   OBJECTIVES: To review the effects of supplementation of vitamin A, or one of its derivatives, during pregnancy, alone or in combination with other vitamins and micronutrients, on maternal and newborn clinical outcomes. SEARCH METHODS: We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (30 March 2015) and reference lists of retrieved studies. SELECTION CRITERIA: All randomised or quasi-randomised trials, including cluster-randomised trials, evaluating the effect of vitamin A supplementation in pregnant women. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed trials for inclusion and risk of bias, extracted data and checked them for accuracy. MAIN RESULTS: We reviewed 106 reports of 35 trials, published between 1931 and 2015. We included 19 trials including over 310,000 women, excluded 15 trials and one is ongoing. Overall, seven trials were judged to be of low risk of bias, three were high risk of bias and for nine it was unclear. 1) Vitamin A alone versus placebo or no treatmentOverall, when trial results are pooled, vitamin A supplementation does not affect the risk of maternal mortality (risk ratio (RR) 0.88, 95% confidence interval (CI) 0.65 to 1.20; four trials Ghana, Nepal, Bangladesh, UK, high quality evidence), perinatal mortality (RR 1.01, 95% CI 0.95 to 1.07; one study, high quality evidence), neonatal mortality, stillbirth, neonatal anaemia, preterm birth (RR 0.98, 95% CI 0.94 to 1.01, five studies, high quality evidence), or the risk of having a low birthweight baby.Vitamin A supplementation reduces the risk of maternal night blindness (RR 0.79, 95% CI 0.64 to 0.98; two trials). There is evidence that vitamin A supplements may reduce maternal clinical infection (RR 0.45, 95% CI 0.20 to 0.99, five trials; South Africa, Nepal, Indonesia, Tanzania, UK, low quality evidence) and maternal anaemia (RR 0.64, 95% CI 0.43 to 0.94; three studies, moderate quality evidence). 2) Vitamin A alone versus micronutrient supplements without vitamin AVitamin A alone compared to micronutrient supplements without vitamin A does not decrease maternal clinical infection (RR 0.99, 95% CI 0.83 to 1.18, two trials, 591 women). No other primary or secondary outcomes were reported 3) Vitamin A with other micronutrients versus micronutrient supplements without vitamin AVitamin A supplementation (with other micronutrients) does not decrease perinatal mortality (RR 0.51, 95% CI 0.10 to 2.69; one study, low quality evidence), maternal anaemia (RR 0.86, 95% CI 0.68 to 1.09; three studies, low quality evidence), maternal clinical infection (RR 0.95, 95% CI 0.80 to 1.13; I² = 45%, two studies, low quality evidence) or preterm birth (RR 0.39, 95% CI 0.08 to 1.93; one study, low quality evidence).In HIV-positive women vitamin A supplementation given with other micronutrients was associated with fewer low birthweight babies (< 2.5 kg) in the supplemented group in one study (RR 0.67, 95% CI 0.47 to 0.96; one study, 594 women). AUTHORS' CONCLUSIONS: The pooled results of three large trials in Nepal, Ghana and Bangladesh (with over 153,500 women) do not currently suggest a role for antenatal vitamin A supplementation to reduce maternal or perinatal mortality. However, the populations studied were probably different with regard to baseline vitamin A status and there were problems with follow-up of women. There is good evidence that antenatal vitamin A supplementation reduces maternal night blindness, maternal anaemia for women who live in areas where vitamin A deficiency is common or who are HIV-positive. In addition the available evidence suggests a reduction in maternal infection, but these data are not of a high quality.


Asunto(s)
Complicaciones del Embarazo/tratamiento farmacológico , Deficiencia de Vitamina A/tratamiento farmacológico , Vitamina A/administración & dosificación , Vitaminas/administración & dosificación , Anemia/prevención & control , Femenino , Humanos , Lactante , Mortalidad Infantil , Recién Nacido , Mortalidad Materna , Ceguera Nocturna/tratamiento farmacológico , Embarazo , Complicaciones Infecciosas del Embarazo/tratamiento farmacológico
6.
Obes Surg ; 23(8): 1244-51, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23462856

RESUMEN

BACKGROUND: This study aims to investigate the nutritional status of vitamin A (VA) using biochemical and functional indicators in subjects with class III obesity, before and after RYGB, supplemented with three protocols. METHODS: The sample comprised 90 patients, with BMI ≥40 kg/m(2), divided into three groups: G1 that received routine supplementation containing 5,000 IU of retinol daily; G2 that received 10,000 IU of retinol daily; and G3 that received routine supplementation plus complementary of 50,000 IU of retinol intramuscularly every month. The status of VA was evaluated before (T0), 30 days (T1), and 180 days (T2) after surgery. RESULTS: The vitamin A deficiency (VAD) in G1, G2, and G3 was respectively 20.7, 21.2, and 20.2 % as regards retinol and 37.8, 63.3, and 40 % as regards ß-carotene in T0; 26.7, 10, and 23.4 % as regards retinol and 68, 37, and 32 % as regards ß-carotene in T1; and 21, 8.7, and 20.2 % as regards retinol and 63.3, 20, and 32 % as regards ß-carotene in T2. A reduction of retinol and ß-carotene with increasing BMI and waist circumference was observed in T0. The prevalence of night blindness (XN) in groups 1, 2, and 3 was respectively 23.3, 26.7, and 16.7 % in T0; 56.7, 40, and 60 % in T1; and 70, 43, and 63.3 % in T2. CONCLUSION: The study showed high prevalence of VAD. Among the supplementation protocols used, the one containing 10,000 IU of retinol showed the best impact. However, in cases of more severe VAD, intramuscular supplementation should be considered. The prevalence of XN, justifies attention to this segment of population.


Asunto(s)
Suplementos Dietéticos , Derivación Gástrica/efectos adversos , Ceguera Nocturna/prevención & control , Obesidad Mórbida/cirugía , Deficiencia de Vitamina A/tratamiento farmacológico , Vitamina A/uso terapéutico , Vitaminas/uso terapéutico , beta Caroteno/uso terapéutico , Adulto , Índice de Masa Corporal , Brasil/epidemiología , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Ceguera Nocturna/sangre , Ceguera Nocturna/tratamiento farmacológico , Ceguera Nocturna/etiología , Estado Nutricional , Periodo Posoperatorio , Prevalencia , Estudios Prospectivos , Resultado del Tratamiento , Deficiencia de Vitamina A/sangre , Deficiencia de Vitamina A/etiología , Circunferencia de la Cintura
7.
JPEN J Parenter Enteral Nutr ; 36(3): 361-4, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22269897

RESUMEN

Biliopancreatic diversion is a predominantly malabsorptive bariatric procedure that can lead to the development of several nutrition complications, including fat-soluble vitamin deficiencies. Routine supplementation with vitamins and trace elements and a strict medical follow-up are essential to prevent these nutrition risks. Vitamin A deficiency is common after bariatric surgery but rarely causes clinical symptoms. Case reports have described ophthalmological and fetal complications associated with vitamin A deficiency after malabsorptive bariatric surgery. Phrynoderma is a type of follicular hyperkeratosis located on the extensor surfaces of the extremities whose main cause is vitamin A deficiency. The simultaneous occurrence of phrynoderma and ocular symptoms secondary to hypovitaminosis A after bariatric surgery is exceptional. The authors describe a man who presented follicular hyperkeratosis with nyctalopia and xerophthalmia that had appeared 1 year after biliopancreatic diversion. He admitted poor compliance with diet and daily supplementation of vitamins and oligoelements. Serum vitamin A levels were decreased. Treatment with high doses of vitamin A was associated with a clear improvement of cutaneous and ocular lesions with complete resolution after 2 months. The patient was readmitted 2 years later because of the reappearance of cutaneous lesions and micronutrient deficiency. Revisional bariatric surgery was performed. The authors review and discuss the relationship between phrynoderma, malnutrition, and vitamin A deficiency.


Asunto(s)
Desviación Biliopancreática/efectos adversos , Queratosis/etiología , Deficiencia de Vitamina A/complicaciones , Deficiencia de Vitamina A/diagnóstico , Dieta , Suplementos Dietéticos , Humanos , Queratosis/tratamiento farmacológico , Queratosis/patología , Masculino , Persona de Mediana Edad , Ceguera Nocturna/tratamiento farmacológico , Ceguera Nocturna/etiología , Obesidad Mórbida/cirugía , Complicaciones Posoperatorias , Vitamina A/administración & dosificación , Vitamina A/sangre , Deficiencia de Vitamina A/tratamiento farmacológico , Xeroftalmia/tratamiento farmacológico , Xeroftalmia/etiología
8.
Nutr Clin Pract ; 26(6): 718-21, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21959340

RESUMEN

This article describes the case of a 16-year-old boy with cystic fibrosis who presented with difficulty seeing in the dark. He had a history of bowel surgery at birth, and he developed cystic fibrosis liver disease and osteopenia during his teenage years. He always had good lung function. When his serum vitamin A level was checked, it was undetectable in sample. He was diagnosed with night blindness and commenced on high-dose vitamin A. His symptoms resolved within 3 days. However, it took over 1 year for his vitamin A level to return to normal. This case emphasizes the importance of monitoring vitamin levels in cystic fibrosis to detect deficiency and prevent long-term consequences, and it highlights the challenges encountered during the course of night blindness treatment.


Asunto(s)
Fibrosis Quística/fisiopatología , Suplementos Dietéticos , Ceguera Nocturna/fisiopatología , Adolescente , Fibrosis Quística/complicaciones , Fibrosis Quística/tratamiento farmacológico , Humanos , Masculino , Ceguera Nocturna/complicaciones , Ceguera Nocturna/tratamiento farmacológico , Resultado del Tratamiento , Vitamina A/sangre , Vitamina A/uso terapéutico , Deficiencia de Vitamina A/sangre , Deficiencia de Vitamina A/tratamiento farmacológico
9.
JAMA ; 305(19): 1986-95, 2011 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-21586714

RESUMEN

CONTEXT: Maternal vitamin A deficiency is a public health concern in the developing world. Its prevention may improve maternal and infant survival. OBJECTIVE: To assess efficacy of maternal vitamin A or beta carotene supplementation in reducing pregnancy-related and infant mortality. DESIGN, SETTING, AND PARTICIPANTS: Cluster randomized, double-masked, placebo-controlled trial among pregnant women 13 to 45 years of age and their live-born infants to 12 weeks (84 days) postpartum in rural northern Bangladesh between 2001 and 2007. Interventions Five hundred ninety-six community clusters (study sectors) were randomized for pregnant women to receive weekly, from the first trimester through 12 weeks postpartum, 7000 µg of retinol equivalents as retinyl palmitate, 42 mg of all-trans beta carotene, or placebo. Married women (n = 125,257) underwent 5-week surveillance for pregnancy, ascertained by a history of amenorrhea and confirmed by urine test. Blood samples were obtained from participants in 32 sectors (5%) for biochemical studies. MAIN OUTCOME MEASURES: All-cause mortality of women related to pregnancy, stillbirth, and infant mortality to 12 weeks (84 days) following pregnancy outcome. RESULTS: Groups were comparable across risk factors. For the mortality outcomes, neither of the supplement group outcomes was significantly different from the placebo group outcomes. The numbers of deaths and all-cause, pregnancy-related mortality rates (per 100,000 pregnancies) were 41 and 206 (95% confidence interval [CI], 140-273) in the placebo group, 47 and 237 (95% CI, 166-309) in the vitamin A group, and 50 and 250 (95% CI, 177-323) in the beta carotene group. Relative risks for mortality in the vitamin A and beta carotene groups were 1.15 (95% CI, 0.75-1.76) and 1.21 (95% CI, 0.81-1.81), respectively. In the placebo, vitamin A, and beta carotene groups the rates of stillbirth and infant mortality were 47.9 (95% CI, 44.3-51.5), 45.6 (95% CI, 42.1-49.2), and 51.8 (95% CI, 48.0-55.6) per 1000 births and 68.1 (95% CI, 63.7-72.5), 65.0 (95% CI, 60.7-69.4), and 69.8 (95% CI, 65.4-72.3) per 1000 live births, respectively. Vitamin A compared with either placebo or beta carotene supplementation increased plasma retinol concentrations by end of study (1.46 [95% CI, 1.42-1.50] µmol/L vs 1.13 [95% CI, 1.09-1.17] µmol/L and 1.18 [95% CI, 1.14-1.22] µmol/L, respectively; P < .001) and reduced, but did not eliminate, gestational night blindness (7.1% for vitamin A vs 9.2% for placebo and 8.9% for beta carotene [P < .001 for both]). CONCLUSION: Use of weekly vitamin A or beta carotene in pregnant women in Bangladesh, compared with placebo, did not reduce all-cause maternal, fetal, or infant mortality. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00198822.


Asunto(s)
Mortalidad Infantil , Mortalidad Materna , Complicaciones del Embarazo/prevención & control , Vitamina A/análogos & derivados , Vitaminas/uso terapéutico , beta Caroteno/uso terapéutico , Adolescente , Adulto , Países en Desarrollo , Suplementos Dietéticos , Diterpenos , Femenino , Humanos , Lactante , Recién Nacido , Persona de Mediana Edad , Ceguera Nocturna/tratamiento farmacológico , Ceguera Nocturna/etiología , Ceguera Nocturna/prevención & control , Embarazo , Resultado del Embarazo , Atención Prenatal , Ésteres de Retinilo , Población Rural , Mortinato , Vitamina A/uso terapéutico , Deficiencia de Vitamina A/complicaciones , Deficiencia de Vitamina A/tratamiento farmacológico , Deficiencia de Vitamina A/prevención & control , Adulto Joven
10.
Ann Hum Biol ; 38(2): 131-6, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20632779

RESUMEN

BACKGROUND: Vitamin A deficiency (VAD) continues to be a major public health nutritional problem in India, even though the National Vitamin A Prophylaxis Programme has been in operation for more than three decades. AIM: To assess the prevalence of vitamin A deficiency among rural pre-school children. SUBJECTS AND METHODS: A community-based cross-sectional study was carried out in rural Madhya Pradesh. A total of 8777 pre-school children were clinically examined for VAD and blood vitamin A levels were estimated in a sub-sample by dried blood spot method. RESULTS: Prevalence of night blindness and Bitot's spot, an objective sign of VAD, was 0.8% and 1.4%, respectively, and prevalence increased significantly (p < 0.001) with age. The proportion of children with blood vitamin A deficiency ( < 20 µg/dL) was 88% (95% CI: 84.8-91.2).The prevalence of Bitot's spot was significantly (p < 0.001) higher among children of lower socio-economic communities, 3-5-year age group and those of illiterate mothers. CONCLUSIONS: VAD is a major public health problem among rural children of Madhya Pradesh. Children of 3-5 years and those belonging to lower socio-economic communities are at high risk of VAD. Therefore, appropriate intervention measures are to be initiated to improve the vitamin A status of children.


Asunto(s)
Salud Rural , Deficiencia de Vitamina A/epidemiología , Vitamina A/sangre , Preescolar , Estudios Transversales , Femenino , Educación en Salud , Humanos , India/epidemiología , Lactante , Masculino , Programas Nacionales de Salud , Ceguera Nocturna/sangre , Ceguera Nocturna/tratamiento farmacológico , Ceguera Nocturna/epidemiología , Encuestas Nutricionales , Prevalencia , Factores Socioeconómicos , Deficiencia de Vitamina A/sangre , Deficiencia de Vitamina A/tratamiento farmacológico , Deficiencia de Vitamina A/prevención & control
11.
Cochrane Database Syst Rev ; (11): CD008666, 2010 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-21069707

RESUMEN

BACKGROUND: The World Health Organization recommends routine vitamin A supplementation during pregnancy or lactation in areas with endemic vitamin A deficiency (where night blindness occurs), based on the expectation that supplementation will improve maternal and newborn outcomes including mortality, morbidity and prevention of anaemia or infection.   OBJECTIVES: To review the effects of supplementation of vitamin A, or one of its derivatives, during pregnancy, alone or in combination with other vitamins and micronutrients, on maternal and newborn clinical outcomes. SEARCH STRATEGY: We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (15 July 2010). SELECTION CRITERIA: All randomised or quasi-randomised trials, including cluster-randomised trials, evaluating the effect of vitamin A supplementation in pregnant women. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed all studies for inclusion and resolved any disagreement through discussion with a third person. We used pre-prepared data extraction sheets. MAIN RESULTS: We examined 88 reports of 31 trials, published between 1931 and 2010, for inclusion in this review. We included 16 trials, excluded 14, and one is awaiting assessment.Overall when trial results are pooled, Vitamin A supplementation does not affect the risk of maternal mortality (risk ratio (RR) 0.78, 95% confidence interval (CI) 0.55 to 1.10, 3 studies, Nepal, Ghana,UK ), perinatal mortality, neonatal mortality, stillbirth, neonatal anaemia, preterm birth or the risk of having a low birthweight baby. Vitamin A supplementation reduces the risk of maternal night blindness (risk ratio (RR) 0.70, 95% CI 0.60 to 0.82, 1 trial Nepal). In vitamin A deficient populations and HIV-positive women, vitamin A supplementation reduces maternal anaemia (risk ratio (RR) 0.64, 95% confidence interval (CI) 0.43 to 0.94, 3 trials, Indonesia, Nepal,Tanzania ). There is evidence that vitamin A supplements may reduce maternal clinical infection (RR 0.37, 95% CI 0.18 to 0.77, 3 trials, South Africa, Nepal and UK).In HIV-positive women vitamin A supplementation given with other micronutrients was associated with fewer low birthweight babies (< 2.5 kg) in the supplemented group in one study (RR 0.67, CI 0.47 to 0.96). AUTHORS' CONCLUSIONS: The pooled results of two large trials in Nepal and Ghana (with almost 95,000 women) do not currently suggest a role for antenatal vitamin A supplementation to reduce maternal or perinatal mortality. However the populations studied were probably different with regard to baseline vitamin A status and there were problems with follow-up of women. There is good evidence that antenatal vitamin A supplementation reduces maternal anaemia for women who live in areas where vitamin A deficiency is common or who are HIV-positive. In addition the available evidence suggests a reduction in maternal infection, but these data are not of a high quality.


Asunto(s)
Complicaciones del Embarazo/tratamiento farmacológico , Deficiencia de Vitamina A/tratamiento farmacológico , Vitamina A/administración & dosificación , Vitaminas/administración & dosificación , Anemia/prevención & control , Femenino , Humanos , Mortalidad Infantil , Recién Nacido , Mortalidad Materna , Ceguera Nocturna/tratamiento farmacológico , Embarazo , Complicaciones Infecciosas del Embarazo/tratamiento farmacológico
12.
BMJ Case Rep ; 20102010 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-22767477

RESUMEN

We present a case of night blindness due to vitamin A deficiency in a gentleman who had previously undergone a pancreaticoduodenostomy 10 years ago. The deficiency was attributed self-cessation of his pancreatic supplements without being aware of the possible consequences. The diagnosis and management of this patient is presented here, along with a discussion of similar cases in the literature.


Asunto(s)
Suplementos Dietéticos , Ceguera Nocturna/tratamiento farmacológico , Ceguera Nocturna/etiología , Deficiencia de Vitamina A/complicaciones , Vitamina A/uso terapéutico , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Ceguera Nocturna/fisiopatología , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/cirugía , Pancreaticoduodenectomía/efectos adversos , Pancreaticoduodenectomía/métodos , Resultado del Tratamiento , Deficiencia de Vitamina A/diagnóstico
13.
J Cyst Fibros ; 7(4): 333-335, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18248859

RESUMEN

This is the first report of a supplemented CF patient presenting with clinical vitamin A deficiency to be successfully treated with zinc therapy alone. Therefore in addition to retinol supplementation, normalizing serum zinc levels may be important in maintaining the vitamin A status of CF patients. The interactions and synergistic effects between the two micronutrients are discussed.


Asunto(s)
Ceguera Nocturna/tratamiento farmacológico , Oligoelementos/uso terapéutico , Sulfato de Zinc/uso terapéutico , Zinc/deficiencia , Fibrosis Quística/complicaciones , Suplementos Dietéticos , Femenino , Humanos , Ceguera Nocturna/diagnóstico , Ceguera Nocturna/etiología , Adulto Joven
14.
Am J Clin Nutr ; 85(5): 1375-84, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17490976

RESUMEN

BACKGROUND: Nightblindness affects 16-52% of pregnant women in areas of Nepal and in some cases persists after vitamin A treatment. Iron and riboflavin affect vitamin A utilization and photoreceptor function, respectively, and pilot data in the study population showed a high prevalence of iron and riboflavin deficiencies. OBJECTIVE: The objective was to assess the effect of supplemental iron and riboflavin on pupillary threshold (PT) and plasma retinol in nightblind, pregnant Nepali women given vitamin A-fortified rice. DESIGN: Nightblind pregnant women were randomly assigned to receive, 6 d/wk under supervision for 6 wk, a vitamin A-fortified rice curry dish providing 850 microg retinal activity equivalents/d with either a 30-mg Fe and 6-mg riboflavin (FeR + VA) capsule or a placebo control (VA only) capsule. Hemoglobin, erythrocyte riboflavin, and plasma ferritin and retinol were measured before and after the intervention. Dark adaptation was assessed by PT score. RESULTS: Women who were iron deficient at baseline (n=38) had significantly greater improvement in PT score with iron and riboflavin supplementation than without (P=0.05). Iron and riboflavin supplements significantly reduced the prevalences of riboflavin deficiency (from 60% to 6%; P<0.0001), iron deficiency anemia (from 35% to 15%; P<0.007), and abnormal PT (from 87% to 30%; P<0.05) from baseline. Mean increases in erythrocyte riboflavin (P<0.0001) and plasma ferritin (P=0.01) were greater in the FeR + VA group than in the VA only group. CONCLUSIONS: Iron deficiency may limit the efficacy of vitamin A to normalize dark adaptation in pregnant Nepali women. Further studies are needed to assess the effect of simultaneous delivery of iron and vitamin A for the treatment of nightblindness.


Asunto(s)
Anemia Ferropénica/tratamiento farmacológico , Hierro de la Dieta/uso terapéutico , Ceguera Nocturna/tratamiento farmacológico , Complicaciones del Embarazo/tratamiento farmacológico , Deficiencia de Riboflavina/tratamiento farmacológico , Riboflavina/uso terapéutico , Vitamina A/uso terapéutico , Adaptación Fisiológica , Adulto , Anemia Ferropénica/epidemiología , Adaptación a la Oscuridad/efectos de los fármacos , Suplementos Dietéticos , Femenino , Alimentos Fortificados , Humanos , Deficiencias de Hierro , Hierro de la Dieta/farmacología , Nepal , Ceguera Nocturna/sangre , Ceguera Nocturna/epidemiología , Oryza , Embarazo , Complicaciones del Embarazo/sangre , Complicaciones del Embarazo/epidemiología , Riboflavina/farmacología , Deficiencia de Riboflavina/sangre , Deficiencia de Riboflavina/epidemiología , Resultado del Tratamiento , Vitamina A/farmacocinética , Complejo Vitamínico B/farmacología , Complejo Vitamínico B/uso terapéutico
15.
Am J Clin Nutr ; 81(2): 461-71, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15699236

RESUMEN

BACKGROUND: It is not known whether daily consumption of vitamin A-containing foods is efficacious for treating nightblindness. OBJECTIVE: We assessed the effect of supplementation with vitamin A from food or synthetic sources on dark adaptation and plasma retinol concentrations in nightblind pregnant Nepali women. DESIGN: Nightblind pregnant women were randomly assigned to 1 of 6 treatment groups to receive 6 d/wk for 6 wk either 850 microg retinol equivalents/d as retinyl palmitate, vitamin A-fortified rice, goat liver, amaranth leaves, or carrots or 2000 microg retinol equivalents/d as retinyl palmitate. Dark adaptation was assessed weekly by using the pupillary threshold (PT) test; plasma retinol concentrations were measured before and after the intervention. These outcomes were also assessed in a comparison group of nonnightblind pregnant women. RESULTS: In the nightblind women, the mean PT improved significantly (P<0.0001) from -0.71+/-0.04 to -1.42+/-0.02 log cd/m2, and the final mean PT did not differ significantly from that in the nonnightblind women (-1.43+/-0.04; P=0.55). Improvement in dark adaptation was greater in the liver group than in the vitamin A-fortified rice group (P<0.02). Plasma retinol concentrations increased significantly (P<0.0001) from 0.95+/-0.05 to 1.07+/-0.05 micromol/L. The plasma retinol response was greater in the higher-dose capsule and liver groups than in the vegetable groups and significantly greater in the liver group than in the vitamin A-fortified rice group (both: P<0.05). CONCLUSION: Improvement in dark adaptation did not differ significantly between women who received vitamin A as liver, amaranth leaves, carrots, or retinyl palmitate.


Asunto(s)
Adaptación a la Oscuridad/efectos de los fármacos , Dieta , Ceguera Nocturna/dietoterapia , Complicaciones del Embarazo/dietoterapia , Deficiencia de Vitamina A/dietoterapia , Vitamina A/análogos & derivados , Vitamina A/administración & dosificación , Adolescente , Adulto , Animales , Diterpenos , Femenino , Alimentos Fortificados , Cabras , Humanos , Hígado/química , Carne , Nepal , Ceguera Nocturna/tratamiento farmacológico , Embarazo , Complicaciones del Embarazo/tratamiento farmacológico , Ésteres de Retinilo , Resultado del Tratamiento , Vitamina A/sangre , Vitamina A/uso terapéutico , Deficiencia de Vitamina A/tratamiento farmacológico
17.
Surv Ophthalmol ; 49(1): 38-50, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-14711439

RESUMEN

We have systematically reviewed placebo-controlled trials of V. myrtillus-extracted anthocyanosides for evidence of positive effects on night vision. Searches of computerized databases and citations in retrieved articles identified 30 trials with outcome measures relevant to vision in reduced light. Of these, 12 were placebo-controlled. The 4 most recent trials were all randomized controlled trials (RCTs) and were negative in outcome. A fifth RCT and 7 non-randomized controlled trials reported positive effects on outcome measures relevant to night vision. Negative outcome was associated with more rigorous methodology but also with lower dose level and extracts from geographically distinct sources that may differ in anthocyanoside composition. Healthy subjects with normal or above average eyesight were tested in 11 of the 12 trials. The hypothesis that V. myrtillus anthocyanosides improves normal night vision is not supported by evidence from rigorous clinical studies. There is a complete absence of rigorous research into the effects of the extract on subjects suffering impaired night vision due to pathological eye conditions. Evidence from methodologically weaker trials and auxiliary evidence from animal studies, trials of synthetic anthocyanosides, and a recent randomized controlled trial of Ribes nigrum (black currant) anthocyanosides may warrant further trials of V. myrtillus anthocyanosides in subjects with impaired night vision.


Asunto(s)
Antocianinas/uso terapéutico , Ceguera Nocturna/tratamiento farmacológico , Extractos Vegetales/uso terapéutico , Vaccinium myrtillus/química , Antocianinas/administración & dosificación , Antocianinas/efectos adversos , Humanos , Extractos Vegetales/administración & dosificación , Extractos Vegetales/efectos adversos , Ensayos Clínicos Controlados Aleatorios como Asunto , Seguridad
18.
Public Health Nutr ; 6(3): 233-44, 2003 May.
Artículo en Inglés | MEDLINE | ID: mdl-12740072

RESUMEN

OBJECTIVES: The impact on vitamin A status of the distribution of vitamin A during national immunisation days (NIDs) has not been well established despite strong promotion by international agencies and donors. Using a pre-post design, the change in prevalence of vitamin A deficiency was examined in pre-school children in Mali. DESIGN: Two cross-sectional surveys were conducted in Mopti region, the first in March 1997 before this strategy was adopted and the second in March 1999, four-and-a-half months after a mass distribution of vitamin A during NIDs. SUBJECTS AND SETTING: We compared the vitamin A status of children aged 12 to 66 months targeted in 1999 by NIDs with the status of children in the same age group in 1997. Infectious events of the previous two weeks were concurrently recorded. Within the 1999 sample, the status of recipient and non-recipient children was also compared. RESULTS: In 1997, the prevalence of xerophthalmia (defined by the presence of night blindness and/or Bitot spots) was 6.9% (95% confidence interval (CI) 5.1-9.2) and the modified retinol dose response (MRDR) test proved abnormal in 77.8% of 12-66-month-old children (95% CI 68.27-85.17). In 1999 this picture had improved significantly, both for xerophthalmia prevalence, 3.3% (95% CI 2.1-5.2), and abnormal MRDR test response, 63.1% (95% CI 54.25-71.23). The infectious morbidity rates between 1997 and 1999 tended to decrease. No significant improvement was found among children older than those targeted by NIDs. In 1999, children who received vitamin A had a lower risk for xerophthalmia (3.0% for recipients vs. 8.7% for non-recipients) and experienced fewer infectious events. CONCLUSIONS: The clinical and biological vitamin A status of pre-school children improved between 1997 and 1999. Mass distribution of vitamin A appears to reduce the occurrence of xerophthalmia and would seem to be associated with a decrease in other related illnesses. Vitamin A supplementation during NIDs should be given a high priority when vitamin A deficiency remains a public health problem.


Asunto(s)
Trastornos de la Nutrición del Niño/epidemiología , Deficiencia de Vitamina A/epidemiología , Vitamina A/administración & dosificación , Xeroftalmia/epidemiología , Antropometría , Trastornos de la Nutrición del Niño/tratamiento farmacológico , Preescolar , Estudios Transversales , Suplementos Dietéticos , Femenino , Humanos , Lactante , Masculino , Malí/epidemiología , Ceguera Nocturna/tratamiento farmacológico , Ceguera Nocturna/epidemiología , Encuestas Nutricionales , Prevalencia , Resultado del Tratamiento , Vitamina A/uso terapéutico , Deficiencia de Vitamina A/tratamiento farmacológico , Xeroftalmia/tratamiento farmacológico
19.
J Nutr ; 131(5): 1510-2, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11340108

RESUMEN

Night blindness occurs commonly among women during pregnancy in rural NEPAL: We examined the relationship between maternal night blindness and the risk of mortality occurring among infants in the first 6 mo of life. Stratified analysis by maternal night blindness status during pregnancy was done for 10,000 women participating in a randomized, placebo-controlled trial of vitamin A and beta-carotene supplementation. Mortality of infants of non-night blind women in all three supplementation groups was similar, and when combined, was 63/1000 live births. Relative to this, mortality was higher by 63% [95% confidence interval (CI): 9-138%) and 50% (95% CI: -3 to 133%) among infants of night blind women receiving placebo and beta-carotene, respectively, but only by 14% (95% CI: -33 to 93%) among those receiving vitamin A. Thus, 6-mo mortality was higher among infants of women who had night blindness during pregnancy. Maternal receipt of vitamin A reduced this risk.


Asunto(s)
Mortalidad Infantil , Ceguera Nocturna/tratamiento farmacológico , Complicaciones del Embarazo/tratamiento farmacológico , Vitamina A/uso terapéutico , beta Caroteno/uso terapéutico , Femenino , Humanos , Lactante , Recién Nacido , Nepal , Embarazo , Probabilidad , Ensayos Clínicos Controlados Aleatorios como Asunto , Factores de Riesgo , Población Rural , Análisis de Supervivencia
20.
Am J Clin Nutr ; 73(6): 1045-51, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11382658

RESUMEN

BACKGROUND: Zinc deficiency may result in abnormal dark adaptation or night blindness, a symptom primarily of vitamin A deficiency. During a placebo-controlled trial in Nepal, weekly vitamin A supplementation of women reduced but failed to eliminate the incidence of night blindness during pregnancy, suggesting a role for zinc. OBJECTIVE: The study examined the efficacy of daily zinc supplementation in restoring night vision of pregnant women who developed night blindness while routinely receiving either vitamin A, beta-carotene, or placebo in a field trial. DESIGN: Women (n = 202) who reported to be night blind during pregnancy were randomly assigned in a double-blind manner, stratified on vitamin A, beta-carotene, or placebo receipt, to receive 25 mg Zn or placebo daily for 3 wk. Thus, the 6 groups studied were as follows: beta-carotene + zinc, beta-carotene alone, vitamin A + zinc, vitamin A alone (vitamin A + placebo), zinc alone (zinc + placebo), and placebo (2 placebos: one for the vitamin A or beta-carotene study and one for the zinc study). Women underwent a clinic-based assessment that included pupillary threshold testing and phlebotomy before and after supplementation. Supplement use and daily history of night blindness were obtained at home twice every week. RESULTS: Zinc treatment increased serum zinc concentrations, but alone (zinc alone group), failed to restore night vision or to improve dark adaptation. However, women in the vitamin A + zinc group who had baseline serum zinc concentrations <9.9 micromol/L were 4 times more likely to have their night vision restored (95% CI: 1.1, 17.3) than were women in the placebo group and tended to have a small improvement in pupillary threshold scores (by 0.21 log candela/m2; P = 0.09). CONCLUSION: These data suggest that zinc potentiated the effect of vitamin A in restoring night vision among night-blind pregnant women with low initial serum zinc concentrations.


Asunto(s)
Ceguera Nocturna/tratamiento farmacológico , Complicaciones del Embarazo/tratamiento farmacológico , Reflejo Pupilar/efectos de los fármacos , Deficiencia de Vitamina A/complicaciones , Vitamina A/uso terapéutico , Zinc/uso terapéutico , Adulto , Método Doble Ciego , Sinergismo Farmacológico , Femenino , Humanos , Nepal , Embarazo , Análisis de Regresión , Resultado del Tratamiento , Zinc/sangre , Zinc/deficiencia , beta Caroteno/administración & dosificación , beta Caroteno/uso terapéutico
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