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Hypervitaminosis A

Sebastien Ellis, Georgios Tsiopanis, Tanuj Lad
Vitamin D is a fat-soluble vitamin essential for calcium homeostasis and bone health. Vitamin D toxicity or hypervitaminosis D is extremely rare. We describe the case of a 73-year-old man who presented with life-threatening hypervitaminosis D and hypercalcaemia resulting from self-medicated doses of vitamin D supplements. This case, alongside other global case reports, highlights the potential dangers of unlicensed vitamin D replacement. We discuss the evidence for vitamin D replacement and remind readers of the current guidance on daily intake and supplementation...
August 2018: Clinical Medicine: Journal of the Royal College of Physicians of London
Vikte Lionikaite, Anna Westerlund, H Herschel Conaway, Petra Henning, Ulf H Lerner
Increased intake of vitamin A (retinoids) is associated with decreased bone mass and increased fracture risk in humans. Mechanistic studies in rodents have shown that hypervitaminosis A results in decreased bone mass caused by an increase in periosteal osteoclasts while simultaneously decreasing endocortic osteoclasts. In vivo and ex vivo bone organ cultures have demonstrated that excess retinoids increase osteoclast formation due to increased receptor activator of nuclear factor kappa B-ligand (RANKL) expression...
July 30, 2018: Journal of Leukocyte Biology
Celia Rodd, AbdulRazaq Sokoro, Lisa M Lix, Laurel Thorlacius, Michael Moffatt, Jim Slater, Eric Bohm
INTRODUCTION: Laboratories have noted marked increases in the analysis of 25-hydroxy vitamin D (25(OH)D) in recent decades. Our objectives were to describe the annual number of 25(OH)D tests, examine the characteristics of those tested and those ordering them, and determine the proportion of potentially unnecessary tests in Manitoba. METHODS: Manitoba residents who were tested between 2006/7 and 2012/13 had their data anonymously linked to Manitoba Centre for Health Policy comprehensive administrative datasets...
July 17, 2018: Clinical Biochemistry
Stephanie J Mondloch, Sherry A Tanumihardjo, Christopher R Davis, Paul J van Jaarsveld
Commonly used in biomedical research, vervets (Chlorocebus aethiops) are omnivorous but primarily meet their vitaminA requirements from provitamin A carotenoids. Hypervitaminosis A has occurred in vervets that consume feed high in preformedvitamin A. We investigated the vitamin A status of vervets supplemented daily with various antioxidants derived from palm oil. Male vervets (n = 40) were placed for 23 wk on a high-fat diet (34.9% energy) containing 645 μg retinol activity equivalents (RAE), with 515 μg RAE from preformed vitamin A...
July 18, 2018: Journal of the American Association for Laboratory Animal Science: JAALAS
Thomas Lind, Roberta Lugano, Ann-Marie Gustafson, Maria Norgård, Arie van Haeringen, Anna Dimberg, Håkan Melhus, Stephen P Robertson, Göran Andersson
Angulated femurs are present prenatally both in CYP26B1 deficient humans with a reduced capacity to degrade retinoic acid (RA, the active metabolite of vitamin A), and mice overexpressing vascular endothelial growth factor a (Vegfa). Since excessive ingestion of vitamin A is known to induce spontaneous fractures and as the Vegfa-induced femur angulation in mice appears to be caused by intrauterine fractures, we analyzed bones from a CYP26B1 deficient human and rats with hypervitaminosis A to further explore Vegfa as a mechanistic link for the effect of vitamin A on bone...
December 2018: Bone Reports
Andoni Echaniz-Laguna, Rachel Mourot-Cottet, Esther Noel, Jean-Baptiste Chanson
Pyridoxine (vitamin B6) is an essential vitamin playing a crucial role in amino acid metabolism. Pyridoxine is used for isoniazid side-effects prevention, pyridoxine-dependent epilepsy treatment and cystathionine beta-synthase deficiency (homocystinuria) treatment. However, vitamin B6 hypervitaminosis is neurotoxic and may provoke a progressive sensory neuronopathy (sensory ganglionopathy), usually when daily uptake is above 50 mg. We describe the case of a 30-year-old patient with homocystinuria who was treated with pyridoxine 1250-1750 mg/day for 20 years and developed progressive sensory neuropathy with ataxia and impaired sensation in the extremities...
June 28, 2018: BMJ Case Reports
Thomas Lind, P Monica Lind, Lijuan Hu, Håkan Melhus
BACKGROUND: The most prominent features of hypervitaminosis A in rats are spontaneous fractures and anorexia. Since caloric restriction induces alterations in bone, some effects could be secondary to loss of appetite. To clarify the mechanisms behind vitamin A-induced bone fragility it is necessary to distinguish between direct and indirect effects. MATERIALS AND METHODS: In this study we compared rats fed high doses of vitamin A both with pair-fed controls, which were fed the same amount of chow as that consumed by the vitamin A group to keep food intake the same, and to controls with free access to food...
June 2018: Upsala Journal of Medical Sciences
Kristen M Williams, Margaret T Lee, Maureen Licursi, Gary M Brittenham, Ilene Fennoy
Patients with sickle cell disease (SCD) are at risk for bone fragility from multiple factors including vitamin D deficiency. To date, no studies have evaluated the efficacy and safety of long-term vitamin D therapy for bone disease in children with SCD. We report a cohort of 4 children with SCD found to have severe vitamin D deficiency, secondary hyperparathyroidism, and abnormal bone mineral density treated with monthly high-dose oral cholecalciferol over 2 years. All patients exhibited a positive response to therapy without hypervitaminosis D or hypercalcemia...
August 2018: Journal of Pediatric Hematology/oncology
Kadie M Anderson, Albert Lewandowski, Patricia M Dennis
An 8 yr, intact male red-rumped agouti ( Dasyprocta leporina) was evaluated for weight loss. Examination revealed poor body condition, hypercalcemia, elevated serum 25-hydroxyvitamin D, metastatic calcification of soft tissues, and hyperechoic kidneys. The diet, formulated for laboratory rodents, contained elevated levels of vitamin D3 . Histopathology from a female conspecific that died 5 mo prior identified dystrophic mineralization and nephrosclerosis, suggestive of a vitamin D3 toxicity. The male agouti responded well to a dietary reduction in vitamin D3 and calcium...
March 2018: Journal of Zoo and Wildlife Medicine: Official Publication of the American Association of Zoo Veterinarians
Agazi Gebreselassie, Alem Mehari, Rahel Dagne, Firehiwet Berhane, Angesom Kibreab
RATIONALE: The usual presentation of sarcoidosis is hilar adenopathy, pulmonary reticular opacities, skin, joint, or eye lesions. Pancreatic involvement is unusual and hypercalcemic pancreatitis as initial manifestation is very rare. PATIENT CONCERNS: We present a case that presented with 1-day history of vomiting, diffuse abdominal pain, and altered mental status. DIAGNOSES: Initial investigations showed highly elevated calcium levels, acute pancreatitis, and kidney failure...
January 2018: Medicine (Baltimore)
Aliaa Al-Mutawa, Alfred Kojo Anderson, Salman Alsabah, Mohammad Al-Mutawa
Obesity is a global epidemic affecting populations globally. Bariatric surgery is an effective treatment for morbid obesity, and has increased dramatically. Bariatric surgery candidates frequently have pre-existing nutritional deficiencies that might exacerbate post-surgery. To provide better health care management pre- and post-bariatric surgery, it is imperative to establish the nutritional status of prospective patients before surgery. The aim of this study was to assess and provide baseline data on the nutritional status of bariatric candidates...
January 11, 2018: Nutrients
Ibrahim O Farah, Carlene Holt-Gray, Joseph A Cameron, Michelle Tucci, Hamed Benghuzzi
The role of retinoic acid (All Trans Retinoic Acid; ATRA) in the development of hypervitaminosis A pathophysiology is not well understood or established in the literature. As well, the role of Citral (inhibitor of retinoid function; a non-toxic chemical that exists in two forms (diethyl; C1 or cis-trans dimethyl; C2).) in the reversal of pathophysiological implications is also not ascertained under an in vivo setting. Therefore, it is hypothesized that ovalbumin exposure will sensitize the body to supra-physiologic levels of retinoic acid leading to a negative pathophysiological impact and that Citrals 1 and 2 will reverse or ameliorate the related damage to the body's pathophysiology...
March 2017: Biomedical Sciences Instrumentation
Victoria J Stokes, Morten F Nielsen, Fadil M Hannan, Rajesh V Thakker
Hypercalcemia is defined as a serum calcium concentration that is greater than two standard deviations above the normal mean, which in children may vary with age and sex, reflecting changes in the normal physiology at each developmental stage. Hypercalcemic disorders in children may present with hypotonia, poor feeding, vomiting, constipation, abdominal pain, lethargy, polyuria, dehydration, failure to thrive, and seizures. In severe cases renal failure, pancreatitis and reduced consciousness may also occur and older children and adolescents may present with psychiatric symptoms...
November 2017: Journal of Bone and Mineral Research: the Official Journal of the American Society for Bone and Mineral Research
Chih-Hao Chang, Chun-Wei Lu, Wen-Hung Chung, Hsin-Chun Ho
INTRODUCTION: Acute fish liver intoxication, including hypervitaminosis A and hypervitaminosis D, may result from the ingestion of certain fish livers. The typical symptoms of hypervitaminosis A include nausea, headache, blurred vision, and cutaneous manifestations, such as flushing, vesicles formation, and desquamation. Hypervitaminosis D may result in hypercalcemia. We report a case of acute fish liver intoxication with systemic and cutaneous manifestations. CASE: A 63-year-old male presented to the clinic with generalized desquamation and multiple clear-fluid filled flaccid vesicles after eating approximately two fist-sized portions (about 300-400 g) of cooked seerfish (Scomberomorus spp...
February 2018: Clinical Toxicology
Sollip Kim, Laura D Stephens, Robert L Fitzgerald
BACKGROUND: In this report, we describe 2 contrasting cases of hypervitaminosis D. CASE PRESENTATION: Patient 1 was a 75-y old man who developed symptomatic hypercalcemia (peak serum calcium concentration of 15.3mg/dl; reference range: 8.5-10.6mg/dl), cardiac injury, and a high total serum vitamin D concentration of 243ng/ml (30-80ng/ml) as a result of daily consumption of prescribed 50,000IU ergocalciferol (vitamin D2) and 500mg calcium-citrate for 1y. Patient 2 was a 60-y old woman who consumed 40,000IU of cholecalciferol (vitamin D3) daily for >10months with a peak total serum vitamin D concentration of 479ng/ml (30-80ng/ml), but did not present with symptoms related to vitamin D toxicity...
October 2017: Clinica Chimica Acta; International Journal of Clinical Chemistry
Mohammed S Razzaque
Vitamin D is a fat-soluble hormone that has endocrine, paracrine and autocrine functions. Consumption of vitamin D-supplemented food & drugs have increased significantly in the last couple of decades due to campaign and awareness programs. Despite such wide use of artificial vitamin D supplements, serum level of 25 hydroxyvitamin D does not always reflect the amount of uptake. In contrast to the safe sunlight exposure, prolonged and disproportionate consumption of vitamin D supplements may lead to vitamin D intoxication, even without developing hypervitaminosis D...
June 2018: Journal of Steroid Biochemistry and Molecular Biology
Anthony R Mawson, Suvankar Majumdar
A geographical and causal connection has long been recognized between malaria, Epstein-Barr virus (EBV) infection and Burkitt's lymphoma (BL), but the underlying mechanisms remain obscure. Potential clues are that the malaria parasite Plasmodium falciparum selectively absorbs vitamin A from the host and depends on it for its biological activities; secondly, alterations in vitamin A (retinoid) metabolism have been implicated in many forms of cancer, including BL. The first author has proposed that the merozoite-stage malaria parasite, emerging from the liver, uses its absorbed vitamin A as a cell membrane destabilizer to invade the red blood cells, causing anemia and other signs and symptoms of the disease as manifestations of an endogenous form of hypervitaminosis A (Mawson AR, Path Global Health 2013;107(3):122-9)...
November 1, 2017: International Journal of Cancer. Journal International du Cancer
Chuangang Peng, Qi Yang, Bo Wei, Yong Liu, Yuxiang Li, Dawei Gu, Guochao Yin, Bo Wang, Dehui Xu, Xuebing Zhang, Daliang Kong
BACKGROUND: The aim was to research the molecular changes of bone cells induced by excessive dose of vitamin A, and analyze molecular mechanism underlying spontaneous fracture. METHODS: The gene expression profile of GSE29859, including 4 cortical bone marrow samples with excessive doses of Vitamin A and 4 control cortical bone marrow samples, was obtained from the Gene Expression Omnibus (GEO) database. Differentially expressed genes (DGEs) between cortical bone marrow samples and control samples were screened out and pathway enrichment analysis was undertaken...
July 2017: Injury
Thomas Lind, Caroline Öhman, Gabriela Calounova, Annica Rasmusson, Göran Andersson, Gunnar Pejler, Håkan Melhus
Calvarial thinning and skull bone defects have been reported in infants with hypervitaminosis A. These findings have also been described in humans, mice and zebrafish with loss-of-function mutations in the enzyme CYP26B1 that degrades retinoic acid (RA), the active metabolite of vitamin A, indicating that these effects are indeed caused by too high levels of vitamin A and that evolutionary conserved mechanisms are involved. To explore these mechanisms, we have fed young mice excessive doses of vitamin A for one week and then analyzed the skull bones using micro computed tomography, histomorphometry, histology and immunohistochemistry...
2017: PloS One
Tania Pilkington, Rex N Brogden
SYNOPSIS: Acitretin (etretin), a second generation monoaromatic retinoid for use in the treatment of severe psoriasis and other dermatoses, is the major active metabolite of etretinate and possesses a similar therapeutic index; i.e. a similar ratio of clinical efficacy to adverse effects. When used alone at a maintenance dosage of 30 to 50mg daily, acitretin is effective in the treatment of psoriasis, causing a reduction in the severity of scaling, erythema and induration. Efficacy appears to be further enhanced by combination with psoralen-ultraviolet A photochemotherapy (PUVA) or ultraviolet B irradiation (UVB)...
April 1992: Drugs
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