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1.
Wilderness Environ Med ; 31(4): 454-456, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32861618

RESUMO

In European countries, vitamin A toxicity is most often the result of an excessive intake of vitamin supplements and rarely the consequence of the ingestion of a large carnivorous fish liver. We report 3 cases of vitamin A poisoning after fish liver ingestion in mainland and overseas France. The patients were a 12-y-old girl, a 36-y-old pregnant woman, and a 62-y-old man. They experienced headache, nausea, emesis, and desquamation. Laboratory examination showed a high serum retinol level in the girl. The woman's pregnancy progressed to a miscarriage. This case series shows that this kind of poisoning is not restricted to the polar regions. In patients presenting with flushing combined with signs of intracranial hypertension, accurate questioning of the patient's diet is crucial to avoid misdiagnosis and unnecessary examinations. Pregnant women or women of child-bearing age should be informed of the risk to pregnancy in the case of excessive fish liver ingestion.


Assuntos
Peixes , Doenças Transmitidas por Alimentos/etiologia , Hipervitaminose A/etiologia , Fígado , Centros de Controle de Intoxicações , Vitamina A/sangue , Adulto , Animais , Criança , Feminino , França , Humanos , Hipervitaminose A/sangue , Hipervitaminose A/patologia , Masculino , Pessoa de Meia-Idade , Gravidez , Complicações na Gravidez
2.
Clin Nutr ; 32(5): 805-10, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23395254

RESUMO

BACKGROUND & AIMS: To determine the vitamin A status and appropriate supplementation dosage of cystic fibrosis (CF) patients who received vitamin A supplementation based on annual serum retinol measurements. METHODS: Vitamin A food intake, supplementation dosage, and serum retinol levels were obtained for 32 CF patients >4 years of age (4.3-27.3 years old) who had pancreatic insufficiency and mild-to-moderate lung disease (percent predicted of forced expiratory volume in 1 s > 40%). These measurements were compared with the dietary reference intake for healthy children and adults (D-A-CH dietary recommendations), US and German CF recommendations, and serum retinol concentrations from National Health and Nutrition Examination Survey (NHANES) data. RESULTS: Total vitamin A intake from food and supplementation was 315% ± 182% of D-A-CH recommendations, with 65% from supplements. The range of the prescribed vitamin A supplementation dosage was 0-20,000 IU/day (median 5500 IU), and it was consistent with CF recommendations in 28% of participants. A quarter of all patients did not need any vitamin A supplementation. The total vitamin A intake exceeded the recommended upper limit of intake in 69% of subjects. The mean (range) serum retinol was 38.6 µg/dl (22.1-59.1 µg/dl). All subjects had serum retinol levels above 20 µg/dl and below 72 µg/dl (95th percentile of NHANES reference range). CONCLUSION: Individualized vitamin A supplementation of 0-20,000 IU/day based on annual serum retinol measurements may prevent deficiency and high serum retinol levels, but it may lead to vitamin A intake above the tolerable upper intake level.


Assuntos
Fibrose Cística/dietoterapia , Suplementos Nutricionais , Hipervitaminose A/prevenção & controle , Medicina de Precisão , Deficiência de Vitamina A/prevenção & controle , Vitamina A/administração & dosagem , Adolescente , Adulto , Obstrução das Vias Respiratórias/etiologia , Criança , Pré-Escolar , Estudos de Coortes , Fibrose Cística/sangue , Fibrose Cística/fisiopatologia , Dieta/efeitos adversos , Suplementos Nutricionais/efeitos adversos , Insuficiência Pancreática Exócrina/etiologia , Feminino , Alemanha/epidemiologia , Humanos , Hipervitaminose A/epidemiologia , Hipervitaminose A/etiologia , Pulmão/fisiopatologia , Masculino , Pâncreas Exócrino/fisiopatologia , Recomendações Nutricionais , Índice de Gravidade de Doença , Vitamina A/efeitos adversos , Vitamina A/sangue , Vitamina A/uso terapêutico , Deficiência de Vitamina A/epidemiologia , Deficiência de Vitamina A/etiologia , Adulto Jovem
3.
Obstet Gynecol Surv ; 67(2): 122-8, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22325302

RESUMO

UNLABELLED: Vitamin A has the unique distinction of being readily available over the counter, yet conferring significant toxic and teratogenic potential. Although vitamin A deficiency is relatively rare in the United States, globally it is the most common cause of blindness. The following is a review of the various forms and derivatives of vitamin A and their associations with potential adverse perinatal outcomes. TARGET AUDIENCE: Obstetricians & Gynecologists, Family Physicians. LEARNING OBJECTIVES: After participating in this CME activity, physicians should be better able to identify sources of Vitamin A, distinguish between toxic and non toxic forms of Vitamin A and counsel patients regarding the dosages of Vitamin A that are tolerable during pregnancy.


Assuntos
Anormalidades Induzidas por Medicamentos , Hipervitaminose A , Complicações na Gravidez , Deficiência de Vitamina A , Vitamina A , Anormalidades Induzidas por Medicamentos/etiologia , Anormalidades Induzidas por Medicamentos/fisiopatologia , Ensaios Clínicos como Assunto , Suplementos Nutricionais/efeitos adversos , Relação Dose-Resposta a Droga , Feminino , Humanos , Hipervitaminose A/etiologia , Hipervitaminose A/fisiopatologia , Recém-Nascido , Medicamentos sem Prescrição/efeitos adversos , Assistência Perinatal/métodos , Assistência Perinatal/normas , Gravidez , Complicações na Gravidez/etiologia , Complicações na Gravidez/fisiopatologia , Estados Unidos/epidemiologia , United States Food and Drug Administration/normas , Vitamina A/administração & dosagem , Vitamina A/efeitos adversos , Vitamina A/análogos & derivados , Vitamina A/metabolismo , Deficiência de Vitamina A/tratamento farmacológico , Deficiência de Vitamina A/epidemiologia , Deficiência de Vitamina A/metabolismo , Deficiência de Vitamina A/fisiopatologia , Vitaminas/administração & dosagem , Vitaminas/efeitos adversos , Vitaminas/análise , Vitaminas/metabolismo , beta Caroteno/administração & dosagem , beta Caroteno/efeitos adversos
5.
Pediatrics ; 118(2): 820-4, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16882846

RESUMO

Numerous vitamin supplements are available over-the-counter to the general public. Some such supplements are available as candy-like chewable preparations to encourage consumption by children. We report 3 cases of overdose of such preparations. Each patient had taken an estimated 200,000 to 300,000 IU of vitamin A. Their circulating vitamin A (retinol and retinyl palmitate) concentrations were monitored over a 6-month period. There were no clinical or biochemical complications noted. However, there were marked increases in both retinol and retinyl palmitate concentrations above age-related reference ranges. In particular, it took 1 to 3 weeks for the serum retinol concentrations to peak and many months for them to normalize. Parents should be warned about the dangers of excessive vitamin consumption. Clinicians should be aware of the late peak in serum retinol concentrations, which may lead to late complications of vitamin A overdose.


Assuntos
Suplementos Nutricionais/efeitos adversos , Hipervitaminose A/etiologia , Vitamina A/análogos & derivados , Biotransformação , Doces , Pré-Escolar , Diterpenos , Overdose de Drogas , Ergocalciferóis/administração & dosagem , Ergocalciferóis/sangue , Ergocalciferóis/farmacocinética , Seguimentos , Hong Kong , Humanos , Masculino , Ésteres de Retinil , Risco , Comprimidos , Vitamina A/administração & dosagem , Vitamina A/efeitos adversos , Vitamina A/sangue , Vitamina A/farmacocinética
6.
Am J Clin Nutr ; 78(6): 1152-9, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14668278

RESUMO

BACKGROUND: It is well established that an excessive intake of retinol (vitamin A) is toxic; however, it has been > 25 y since the last extensive treatise of case reports on this subject. OBJECTIVE: The objectives were to identify and evaluate all individual cases of retinol toxicity published in the scientific literature that assessed the thresholds and symptoms induced by high intakes of retinol and to compare the toxicity of different physical forms of retinol preparations. DESIGN: We performed a meta-analysis of case reports on toxicity claimed to be induced by intakes of excessive amounts of dietary retinol (ie, retinol and retinyl esters in foods or supplements). Using free text and MESH (medical subheading) strategies in PubMed, we identified 248 articles in the scientific literature. From these initial articles we identified other relevant citations. The final database consisted of 259 cases in which individual data on dose, sex, age, time of exposure, and symptoms are reported. RESULTS: Chronic hypervitaminosis A is induced after daily doses of 2 mg retinol/kg in oil-based preparations for many months or years. In contrast, doses as low as 0.2 mg retinol. kg(-1). d(-1) in water-miscible, emulsified, and solid preparations for only a few weeks caused chronic hypervitaminosis A. Thus, water-miscible, emulsified, and solid preparations of retinol are approximately 10 times as toxic as are oil-based retinol preparations. The safe upper single dose of retinol in oil or liver seems to be approximately 4-6 mg/kg body wt. These thresholds do not vary considerably with age. CONCLUSIONS: The results of the present study indicate that the physical form of retinol supplements is a major determinant of toxicity. The use of water-miscible, emulsified, and solid preparations of retinol should therefore be carefully considered before being used in supplements and fortifications.


Assuntos
Hipervitaminose A/etiologia , Vitamina A/administração & dosagem , Vitamina A/efeitos adversos , Adolescente , Química Farmacêutica , Criança , Pré-Escolar , Suplementos Nutricionais , Relação Dose-Resposta a Droga , Emulsões , Feminino , Humanos , Hipervitaminose A/prevenção & controle , Lactente , Recém-Nascido , Masculino , Solubilidade , Vitamina D/administração & dosagem
7.
Acta Paediatr ; 84(8): 863-6, 1995 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7488807

RESUMO

To evaluate the safety of vitamin A supplementation in early infancy using DPT/OPV immunization contracts, a double-blind, randomized, placebo-controlled trial was conducted in Bangladesh. One hundred and sixty-seven infants received three doses of either 25,000 IU of vitamin A or a placebo at about 6.5, 11.8 and 17.0 weeks of age. Trained physicians examined each of the infants on days 1, 2, 3 and 8 after supplementation. Nine infants (10.5%) supplemented with vitamin A had episodes of bulging of the fontanelle compared with two infants (2.5%) in the placebo group (p < 0.05). Twelve of the 14 episodes occurred in infants supplemented with vitamin A. Of these 12 episodes, none occurred with the first dose, 3 occurred with the second and 9 with the third dose. The higher incidence of bulging of the fontanelle in the vitamin A group relative to the placebo group and its temporal association with the vitamin A doses are suggestive of a causal association. The finding that increased numbers of vitamin A doses were associated with a higher probability of bulging of the fontanelle suggests a cumulative effect.


Assuntos
Países em Desenvolvimento , Hipervitaminose A/etiologia , Programas de Imunização , Pseudotumor Cerebral/induzido quimicamente , Vitamina A/efeitos adversos , Bangladesh , Vacina contra Difteria, Tétano e Coqueluche/administração & dosagem , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Lactente , Masculino , Vacina Antipólio Oral/administração & dosagem , Pseudotumor Cerebral/diagnóstico , População Urbana , Vitamina A/administração & dosagem
8.
Am J Kidney Dis ; 25(2): 346-9, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7847365

RESUMO

We present two cases of hemodialysis patients developing vitamin A toxicity related to excessive consumption of nutritional supplements containing large quantities of vitamin A. In one patient, severe hypercalcemia was the lone presenting sign; in the other, hypercalcemia was associated with unusual neurologic manifestations. We will discuss the reason why hemodialysis patients are at special risk for the development of hypervitaminosis A and review the mechanism leading to the associated hypercalcemia.


Assuntos
Hipervitaminose A/etiologia , Diálise Renal , Adulto , Humanos , Hipercalcemia/etiologia , Falência Renal Crônica/complicações , Falência Renal Crônica/terapia , Masculino , Pessoa de Meia-Idade
9.
Am J Clin Nutr ; 52(2): 183-202, 1990 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2197848

RESUMO

Toxicity has been associated with abuse of vitamin A supplements and with diets extremely high in preformed vitamin A. Consumption of 25,000-50,000 IU/d for periods of several months or more can produce multiple adverse effects. The lowest reported intakes causing toxicity have occurred in persons with liver function compromised by drugs, viral hepatitis, or protein-energy malnutrition. Certain drugs or other chemicals may markedly potentiate vitamin A toxicity in animals. Especially vulnerable groups include children, with adverse effects occurring with intakes as low as 1,500 IU.kg-1.d-1, and pregnant women, with birth defects being associated with maternal intakes as low as approximately 25,000 IU/d. The maternal dose threshold for birth defects cannot be identified from present data. An identifiable fraction of the population surveyed consumes vitamin A supplements at 25,000 IU/d and a few individuals consume much more. beta-Carotene is much less toxic than vitamin A.


Assuntos
Hipervitaminose A/etiologia , Vitamina A/efeitos adversos , Anormalidades Induzidas por Medicamentos/etiologia , Animais , Carotenoides/efeitos adversos , Carotenoides/metabolismo , Carotenoides/toxicidade , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Humanos , Hepatopatias/metabolismo , Vitamina A/administração & dosagem , Vitamina A/toxicidade , beta Caroteno
10.
Chest ; 97(5): 1260, 1990 May.
Artigo em Inglês | MEDLINE | ID: mdl-2331929

RESUMO

The use of various dietary supplements containing fish oils has become popular as a method of reducing the risk of developing cardiovascular disease. However, consumption of large amounts of these substances may pose some potential hazards. Described herein is a patient who developed hypervitaminosis A after prolonged fish oil supplement ingestion.


Assuntos
Óleos de Peixe/efeitos adversos , Hipervitaminose A/etiologia , Automedicação/efeitos adversos , Adulto , Óleos de Peixe/administração & dosagem , Humanos , Masculino , Fatores de Tempo
11.
Nurse Pract ; 14(8): 28, 30-1, 1989 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2671824

RESUMO

The increasing incidence of vitamin A toxicity is related to vitamin A supplementation for unfounded reasons. This article describes the common symptomatology of vitamin A toxicity, including hypercalcemia, hepatomegaly, and dermatological and neurological effects. Retinol supplements, but not carotene supplements, become toxic when free retinol circulates. Responsibilities of health professionals include questioning vitamin use when taking health histories, educating themselves with scientifically based nutritional studies and applying RDAs (recommended daily allowances) when advising clients.


Assuntos
Hipervitaminose A/diagnóstico , Automedicação/efeitos adversos , Pré-Escolar , Humanos , Hipervitaminose A/etiologia , Hipervitaminose A/fisiopatologia , Masculino , Vitamina A/fisiologia
12.
Am J Clin Nutr ; 49(1): 112-20, 1989 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2911996

RESUMO

We studied the relationships of supplemental and total vitamin A and supplemental vitamin E intake with fasting plasma biochemical indicators of vitamin A and vitamin E nutritional status among 562 healthy elderly people (aged 60-98 y) and 194 healthy young adult (aged 19-59 y) volunteers. All subjects were nonsmokers. For the young adults, plasma retinol was significantly greater in males than in females (p less than 0.01); retinol was not related to supplemental vitamin A intake for either group. Fasting plasma retinyl esters demonstrated a significant increase with vitamin A supplement use. For supplemental vitamin A intakes of 5001-10,000 IU/d, a 2.5-fold increase over nonusers in fasting plasma retinyl esters was observed for elderly people (p less than 0.05) and a 1.5-fold increase for young adults (p greater than 0.20). For elderly people, greater fasting plasma retinyl esters were associated with long-term vitamin A supplement use (greater than 5 y) and biochemical evidence of liver damage. Elderly people who take vitamin A supplements may be at increased risk for vitamin A overload.


Assuntos
Envelhecimento/sangue , Carotenoides/sangue , Colesterol/sangue , Alimentos Fortificados , Proteínas de Ligação ao Retinol/sangue , Vitamina A/análogos & derivados , Vitamina A/administração & dosagem , Vitamina A/sangue , Vitamina E/administração & dosagem , Vitamina E/sangue , Idoso , Idoso de 80 Anos ou mais , Diterpenos , Jejum , Feminino , Humanos , Hipervitaminose A/sangue , Hipervitaminose A/etiologia , Masculino , Pessoa de Meia-Idade , Proteínas Plasmáticas de Ligação ao Retinol , Ésteres de Retinil
15.
Ann Intern Med ; 105(6): 877-9, 1986 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3777711

RESUMO

A 48-year-old woman with malabsorption and type V hyperlipoproteinemia developed hypervitaminosis A with a total plasma vitamin A level of 871 micrograms/dL during therapy with an oral dosage of 18,000 retinol equivalents (60,000 IU) daily. Twelve percent of the total plasma retinol was found to be transported in the chylomicron-very low density lipoprotein (VLDL) fraction, which does not contain retinol-binding protein. For comparison, concentrations of retinyl esters and retinol were determined in nine patients with type V hyperlipoproteinemia and nine control subjects, none of whom were using vitamin A supplements. Both retinyl esters and retinol were significantly elevated in the group with hyperlipoproteinemia (p less than 0.0005 in both cases). Eight of these nine patients had retinol present in the chylomicron-VLDL fraction, whereas retinol was not detectable in this fraction in any of the nine normal controls. The data suggest that patients with severe hypertriglyceridemia associated with type V hyperlipoproteinemia are at increased risk for hypervitaminosis A.


Assuntos
Hiperlipoproteinemia Tipo V/complicações , Hipervitaminose A/etiologia , Feminino , Humanos , Hiperlipoproteinemia Tipo V/sangue , Síndromes de Malabsorção/complicações , Síndromes de Malabsorção/tratamento farmacológico , Pessoa de Meia-Idade , Triglicerídeos/sangue , Vitamina A/sangue
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