Hypervitaminosis A Following the Ingestion of Fish Liver: Report on 3 Cases from the Poison Control Center in Marseille.

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.

Vitamin A and Retinoids as Mitochondrial Toxicants.

Vitamin A and its derivatives, the retinoids, are micronutrient necessary for the human diet in order to maintain several cellular functions from human development to adulthood and also through aging. Furthermore, vitamin A and retinoids are utilized pharmacologically in the treatment of some diseases, as, for instance, dermatological disturbances and some types of cancer. In spite of being an essential micronutrient with clinical application, vitamin A exerts several toxic effects regarding redox environment and mitochondrial function. Moreover, decreased life quality and increased mortality rates among vitamin A supplements users have been reported. However, the exact mechanism by which vitamin A elicits its deleterious effects is not clear yet. In this review, the role of mitochondrial dysfunction in the mechanism of vitamin A-induced toxicity is discussed.

Clinical associations of hepatic stellate cell (HSC) hyperplasia.

Hepatic stellate cell (HSC) hyperplasia has been principally attributed to hypervitaminosis A. There are sporadic reports of HSC hyperplasia in other conditions such as chronic biliary disease and hepatitis C, but clinical associations of this entity have not been studied in detail. We aimed to investigate the clinical associations of HSC hyperplasia aside from hypervitaminosis A. We identified 34 patients whose liver histology showed HSC hyperplasia. We reviewed the liver samples; additional histologic findings in addition to HSC hyperplasia were consolidated into a histologic diagnosis. We collected clinical, laboratory, and radiologic data; the histologic diagnosis was combined with this data to reach an "overall diagnosis." Four patients had hypervitaminosis A (all native livers). In native livers (n = 24), HSC hyperplasia also occurred in association with drug-induced hepatitis [n = 6, niacin was the most common inducing agent (n = 3)], reactive hepatitis (n = 4), chronic hepatitis C (n = 4), autoimmune hepatitis (n = 3), steatohepatitis (n = 1), chronic biliary disease (n = 1), and portal venopathy (n = 1). In liver allografts (n = 10), HSC hyperplasia was seen in protocol biopsies without other significant abnormalities (n = 5), chronic biliary disease (n = 4), and acute cellular rejection (n = 1). All patients used medications (total of 99) and 82 % were on multiple medications. HSC hyperplasia is an uncommon and relatively nonspecific finding that most commonly occurs in multimedicated patients, often in the absence of hypervitaminosis A. Associated conditions include drug toxicity (such as niacin), post-liver transplant setting, reactive hepatitis (due to systemic illness or inflammatory disorders of the gastrointestinal tract), and chronic liver disease.

Increased dietary intake of vitamin A promotes aortic valve calcification in vivo.

OBJECTIVE: Calcific aortic valve disease (CAVD) is a major public health problem with no effective treatment available other than surgery. We previously showed that mature heart valves calcify in response to retinoic acid (RA) treatment through downregulation of the SRY transcription factor Sox9. In this study, we investigated the effects of excess vitamin A and its metabolite RA on heart valve structure and function in vivo and examined the molecular mechanisms of RA signaling during the calcification process in vitro. METHODS AND RESULTS: Using a combination of approaches, we defined calcific aortic valve disease pathogenesis in mice fed 200 IU/g and 20 IU/g of retinyl palmitate for 12 months at molecular, cellular, and functional levels. We show that mice fed excess vitamin A develop aortic valve stenosis and leaflet calcification associated with increased expression of osteogenic genes and decreased expression of cartilaginous markers. Using a pharmacological approach, we show that RA-mediated Sox9 repression and calcification is regulated by classical RA signaling and requires both RA and retinoid X receptors. CONCLUSIONS: Our studies demonstrate that excess vitamin A dietary intake promotes heart valve calcification in vivo. Therefore suggesting that hypervitaminosis A could serve as a new risk factor of calcific aortic valve disease in the human population.

Hypervitaminosis A inducing intra-hepatic cholestasis--a rare case report.

The use of over-the-counter supplements is commonplace in today's health conscious society. We present an unusual case of intrahepatic cholestasis caused by vitamin A intoxication. The patient consumed one Herbalife shake with two multivitamin tablets of the same brand for 12 years. When calculated this equated to more than the recommended daily allowance for vitamin A consumption. Deranged liver function tests were consistent with a cholestatic process. Liver biopsy was obtained and revealed features pathognomonic of vitamin A toxicity, without the usual fibrosis. When the supplements were ceased, his jaundice and alkaline phosphatase completely normalized. This case highlights the importance of health care providers documenting non-prescribed dietary supplements and considering them in the etiology of cholestatic liver disease.

The effects of hypervitaminosis A in sheep following intramuscular administrations of vitamin A.

Ten ewe lambs (median age 11 months and average weight 29.2+/-2.5 kg) were used in the present study. They were divided into two groups: test (n=5) and control (n=5). Housing and all diets were identical. In the test group vitamin A was injected into the thigh muscle at a daily dose of 5000 IU/kg body weight for 16 days. The average final body weight of sheep in the test group was significantly (P<0.05) less than the control group. All animals were slaughtered at day 17. The lambs' feet were X-rayed to evaluate any difference for radiographic signs between test and control groups. No significant differences were seen for PCV, WBC, differential leukocyte count, and total serum protein between groups. There were no significant differences for serum AST, ALT, and ALP activities and serum calcium, inorganic phosphate, and magnesium concentrations between groups. Histological examination revealed an increased number of lipid droplets in the cytoplasm of the stellate cells of the liver in the test group. The results showed that daily administrations of vitamin A approximately 150 times greater than the daily requirement were well tolerated by sheep.

Hypervitaminosis A-induced premature closure of epiphyses (physeal obliteration) in humans and calves (hyena disease): a historical review of the human and veterinary literature.

Vitamin A toxicity in the infant, which now occurs rarely from dietary overdosage, was recognized in the 1940s as painful periostitis with rare progression to premature closure of the lower limb epiphyses. Decades later, most cases of vitamin A-induced premature epiphyseal closure (physeal obliteration) occur in pediatric dermatologic patients given vitamin A analogues. This phenomenon resembles a strange disease discovered in more recent years in calves with closed epiphyses of the hind limbs, known as hyena disease. This was a mystery until proved to be caused by vitamin A toxicity from enriched grain that causes the calves to have short hind limbs that resemble those of a hyena and gait disturbance. This historical review links the human and veterinary literature in terms of vitamin A-induced epiphyseal closure using a case report format of a 16-month-old human infant with closed knee epiphyses and gait disturbance that is reminiscent of hyena disease seen in calves.

Vitamin A toxicity: when one a day doesn't keep the doctor away.

Vitamin A toxicity has been reported to cause severe liver disease and, occasionally, liver failure. Herein we present the case of a 60-year-old male with symptoms of muscle soreness, alopecia, nail dystrophy, and ascites. He continued to deteriorate with the development of refractory ascites, renal insufficiency, encephalopathy, and failure to thrive. A liver biopsy demonstrated presence of Ito cells and vacuolated Kupffer cells without the presence of cirrhosis. His clinical history revealed ingestion of large doses of vitamin A. His worsening clinical situation ruled out the possibility of a transjugular intrahepatic portosystemic shunt. The patient underwent orthotopic liver transplantation with resolution of symptoms. Vitamin A toxicity should be considered in the differential diagnosis of noncirrhotic portal hypertension. In conclusion, liver transplantation is a valid option if no improvement occurs in spite of cessation of the medication.

Vitamin A toxicosis in a lorikeet flock.

Vitamin A toxicosis has recently been recognized as a concern for granivorous birds such as cockatiels (Nymphicus hollandicus) and nectarivorous birds such as lorikeets. Such birds have little exposure to performed vitamin A in their wild diet, relying on carotene conversion to supply their vitamin A needs. Multiple clinical problems arose in a lorikeet flock when excessive vitamin A supplementation was used.

Hypervitaminosis A-induced liver fibrosis: stellate cell activation and daily dose consumption.

UNLABELLED: Hypervitaminosis A-related liver toxicity may be severe and may even lead to cirrhosis. In the normal liver, vitamin A is stored in hepatic stellate cells (HSC), which are prone to becoming activated and acquiring a myofibroblast-like phenotype, producing large amounts of extracellular matrix. AIMS: In order to assess the relationship between vitamin A intake, HSC activation and fibrosis, we studied nine liver biopsies from patients belonging to a well-characterized series of 41 patients with vitamin A hepatotoxicity. METHODS: Fibrosis was underlined by Sirius-red staining, whereas activated HSC were immunohistochemically identified using an antibody against alpha smooth muscle actin. The volume density (Vv) of sinusoidal and total fibrosis and of sinusoidal and total activated HSC was quantified by the point-counting method. RESULTS: Morphology ranged from HSC hypertrophy and hyperplasia as the sole features to severe architectural distortion. There was a significant positive correlation between Vv of perisinusoidal fibrosis and the daily consumption of vitamin A (P=0.004). CONCLUSION: The close correlation between the severity of perisinusoidal fibrosis and the daily dose of the retinol intake suggests the existence of a dose-effect relationship.

Infant hypervitaminosis A causes severe anemia and thrombocytopenia: evidence of a retinol-dependent bone marrow cell growth inhibition.

Vitamin A is a pivotal biochemical factor required for normal proliferation and differentiation as well as for specialized functions, such as vision. The dietary intake of 1500 IU/day is recommended in the first year of life. Here, we report the case of an infant who had been given 62 000 IU/day for 80 days. The infant showed several clinical signs of retinol intoxication, including severe anemia and thrombocytopenia. Bone marrow showed a remarkably reduced number of erythroid and megakaryocytic cells. The interruption of vitamin A treatment was immediately followed by clinical and biochemical recovery. To clarify whether the effects of retinol are due to a direct action on bone marrow cell proliferation, we investigated the activity of retinol (both the drug and the pure molecule) on the growth of K-562, a multipotent hematopoietic cell line, and on bone marrow mesenchymal stem cells. We observed that vitamin A strongly inhibited the proliferation of the cells at concentrations similar to those reached in vivo. Subsequent biochemical analyses of the cell cycle suggested that the effect was mediated by the up-regulation of cyclin-dependent kinase inhibitors, p21(Cip1) and p27(Kip1). These are the first findings to demonstrate that infant hypervitaminosis A causes a severe anemia and thrombocytopenia and that this is probably due to the direct effect of the molecule on the growth of all bone marrow cellular components. Our data also suggest potential bone marrow functional alterations after excessive vitamin A intake because of emerging social habits.

Possible role of endogenous retinoid (Vitamin A) toxicity in the pathophysiology of primary biliary cirrhosis.

Primary biliary cirrhosis (PBC) is a chronic, cholestatic disease of unknown etiology commonly affecting women. It is characterized by progressive destruction of the small intrahepatic bile ducts and portal inflammation, leading to fibrosis and cirrhosis. The major signs and symptoms of PBC, which include pruritus, lethargy, the sicca syndrome, and osteoporosis, closely resemble the manifestations of hypervitaminosis A. Based on a review of the literature and other observations connecting PBC with retinoid metabolism (vitamin A and its derivatives), the hypothesis is proposed that exposure to excess endogenous retinoids contributes to the pathogenesis of PBC and may be to the cause of some of the signs and symptoms associated with the disease.

Vitamin A toxicity secondary to excessive intake of yellow-green vegetables, liver and laver.

We report a case of sudden onset of vitamin A poisoning. A 20-year-old Japanese woman had been eating pumpkin and only a very limited amount of other foods on a daily basis for 2 years. She was overly concerned about weight reduction. Aurantiasis cutis and abnormal liver function tests were noted by her family doctor in 1995 when she was 18 years old. At that time, she stopped eating pumpkin. However, she secretly continued an excessive intake of other beta-carotene-rich vegetables, liver and laver for about 2 years. Two and one-half years after being seen by her family physician, she experienced sudden onset of low-grade fever, limb edema, cheilitis, dry skin, and headache. These symptoms worsened daily. A liver needle biopsy was performed, and it showed a normal portal tract along with fat-laden Ito cells in the space of Disse. A final diagnosis of vitamin A poisoning and hepatic injury secondary to an eating disorder was made. Her symptoms and serum beta-carotene levels returned to normal with successful adjustment of her diet.

[Benign intracranial hypertension and chronic hypervitaminosis A]. / Hypertension intracrânienne bénigne et hypervitaminose A chronique.

We report a case of benign intracranial hypertension due to chronic A-hypervitaminosis and a review of literature with 30 cases in adults and adolescents. The most prominent clinical features are: predominance of young women with normal weight and cured for acne; benign intracranial hypertension without other symptoms in half of cases; wide difference of daily doses and time of continuous intake. Prognosis for vitamin A intoxication is good, when intake of vitamin is discontinued. We reviewed five cases of benign intracranial hypertension due to retinoic acid. The mechanism of vitamin A neurotoxicity is still unknown.

Local disappearance of epiphyseal growth plates in rats with hypervitaminosis A.

Epiphyseal growth plates of proximal tibiae in rats with high doses of vitamin A (V-A) were observed. Of 4 groups, each consisting of 5 rats, three groups were given V-A at doses, IU/100 g by body weight/day, of 50,000, 100,000, and 150,000, respectively. The other group rats were given no V-A (control). Rats were administered V-A for the 5 days from 4 weeks after birth and sacrificed at 12 weeks after birth. Three rats of the 150,000 IU group died during the period of observation. The decalcified sections were stained with hematoxylin-eosin or toluidine blue. In the ground sections, microradiography, backscattered electron imaging, and energy-dispersive X-ray microanalysis were performed. These observations suggest that the local disappearance of epiphyseal growth plates under high doses of V-A goes in the order of the increased doses through the process of (1) calcified cartilage areae appearing in the resting cell zone, (2) some of the calcified areae extending in the growth plate towards the diaphysial side, (3) bone tissue replacing the calcified areae, and (4) the local disappearing of the growth plate. Such a local disappearance may be formed in the stressed proximal regions of tibiae.

Gastric ulceration and suspected vitamin A toxicosis in grower pigs fed fish silage.

In 3 feeding trials, gastric ulceration was diagnosed in 2 of 12 lame and recumbent grower pigs fed a diet of 50% fish silage produced from the offal of farmed Atlantic salmon. Premature femoral physeal closure and elevated serum retinyl palmitate levels, features of vitamin A toxicosis, were also observed.

Effect of vitamin A excess on germ cell development in prepubertal rat testis.

Vitamin A in graded doses of 125, 250 and 375 U.S.P./kg body wt, po, for 10 days (d 21-30) drastically reduced the testicular weight by 25 to 62% and seminiferous tubular diameter by 14 to 35% in prepubertal rats in lowest and highest doses of the treatment. The treatment induced disproportionate enlargement of nuclei and cytoplasm of the germ cells; predominantly the preleptotene and pachytene spermatocytes. These abnormal germ cells, often with 2 or 3 nuclei displayed vacuolated cytoplasm surrounding pyknotic or granulated or dispersed chromatin granules within the nuclei in a dose proportionate manner. The round spermatids were the most sensitive cell types which completely disappeared in two higher doses of treatment. Vacuolation of Sertoli cell cytoplasm in about 25% of the tubules with associated increase in intertubular space was also observed in rats treated with the highest dose of the vitamin. Circulatory levels of FSH, LH and testosterone remained unaltered following the vitamin excess treatment. Therefore, it is suggested that excess vitamin A even for shorter duration like the present one is detrimental to developing cell types and prevents the progress of the spermatogenic process beyond the round spermatid stage.

Vitamin (A and D)-induced premature physeal closure (hyena disease) in calves.

Hypervitaminosis A and D is a potential cause of "hyena disease" in cattle, which results from premature growth-plate closure in long bones of calves. This study showed that vitamin A induced growth-plate closure if calves were given an intramuscular injection of vitamins A and D (2,000,000 IU and 300,000 IU, respectively) on the first day after birth and, in addition, vitamin A (30,000 IU/kg body weight) in a water dispersible form was added to the milk substitute daily. Gross lesions were observed in the proximal tibial growth plates of each of seven calves after 3 weeks of vitamin-A treatment. Microscopical examination showed commencing premature growth-plate closure in the proximal tibia at 2 weeks. After one week, the growth plate showed focal thinning, and there was premature endochondral ossification of columnar cartilage. Longitudinal bone growth was dramatically reduced before growth plate closure at one week (25 microns/day in a treated animal versus 136 microns/day in a control). Liver concentrations of retinol and retinyl palmitate became strikingly elevated at on week, and thereafter increased slowly until the third week. Elevation of plasma retinol and retinyl palmitate was rapid, reaching a maximum on day 10. Plasma all-trans-retinoic acid was undetectable in many samples from treated animals, but plasma concentrations of derivatives of retinoic acid (9-cis-retinoic acid, 13-cis-retinoic acid, 13-cis-4-oxoretinoic acid, and 9, 13 dicis-retinoic acid) were elevated. The vitamin-A intake required to induce growth-plate closure in calves was found to be exceedingly high. Vitamin-A toxicity must be considered as a potential cause of hyena disease, but it would seem likely that other factors also play a role.