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

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.     

Suprahepatic Budd-Chiari syndrome treated with thrombectomy and cavoplasty

The case of a 42-year-old female with Budd-Chiari syndrome (BCS) and lupus anticoagulant is reported. This patient, who had been on chronic anticoagulants for her lupus anticoagulant, presented with abdominal pain, dyspnea on exertion, engorged abdominal wall venous collaterals, and hepatomegaly. A dynamic computerized tomography of the abdomen showed complete suprahepatic inferior vena caval occlusion at the junction with the right atrium. IVC venogram confirmed the diagnosis and also demonstrated patency of the hepatic veins. Free hepatic venous pressure was 25-26 mm Hg. Histopathologic examination of the liver showed marked central venous congestion with significant bridging fibrosis. The total caval occlusion and overt calcification of the clot precluded radiologic angioplasty, and the patient underwent a successful surgical thrombectomy with cavoplasty utilizing an autologous venous patch. Several weeks following surgery, she was free of symptoms and resumed her usual daily activities. Follow-up venography showed a widely opened cava with normal free hepatic vein pressures. Repeat liver biopsy at 6 months showed complete resolution of the hepatic venous congestion and a decrease in the degree of fibrosis.     

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.     

Hepatic hyper-vitaminosis A: importance of retinyl ester level determination

We report the case of a 32-year-old man with portal hypertension without cirrhosis due to chronic vitamin A intoxication. Portal hypertension revealed by oesophageal varice rupture progressively worsened and ascites occurred 5 years after the patient stopped vitamin A intake. Initially, serum retinyl palmitate concentration was increased whereas serum retinol concentration was normal. There was no hepatic fibrosis on light microscopic examination of liver biopsy specimens. Five years after the patient stopped excessive vitamin A intake, serum retinol and retinol-binding protein concentrations were below the normal range even though there was an increased hepatic retinyl ester content. This was attributed to the late development of peri-sinusoidal fibrosis. This case mainly shows the importance of retinyl ester level determination: serum retinyl palmitate should be measured immediately after intoxication and hepatic retinyl esters should be measured initially and particularly later. Indeed, later serum and hepatic retinol levels in chronic hyper-vitaminosis A may be normal and lead to under-estimation of liver vitamin A overload.     

Vitamin A toxicity in a physical culturist patient: a case report and review of the literature

Excessive intake of vitamin A may produce acute or chronic toxicity. Vitamin A can be consumed in foods, fortified products and supplements. We present a case of a young physical culturist man who was referred to our Unit because of chronic liver disease of unknown origin. The patient had a history of increased vitamin A intake from natural source with the addition of high dose of vitamin A supplements with the purpose of improving his muscular development. Our patient showed chronic liver disease with severe fibrosis, signs of portal hypertension and marked hyperplasia of Ito cells. In conclusion, chronic vitamin A toxicity may produce severe liver damage and should be recognized in the differential diagnosis of chronic liver diseases.     

Liver damage caused by therapeutic vitamin A administration: estimate of dose-related toxicity in 41 cases

Clinical presentation, changes in liver function test results, and liver morphology were examined in 41 consecutive patients with vitamin A hepatoxicity. The cause of liver disease was suspected at initial interview in only 13 instances, whereas histological evidence of fat-storing cell hyperplasia with fluorescent vacuoles led to the diagnosis in the remaining cases. Cirrhosis was found in 17, mild chronic hepatitis in 10, noncirrhotic portal hypertension in 5, and "increased storage" alone in 9 cases. During a mean follow-up period of 4.6 years, 6 patients died of causes related to the liver disease. A precise appraisal of drug consumption was obtained in 29 cases. Among them the total cumulative intake was the highest in patients with cirrhosis (423 +/- 103 x 10(6) IU) and significantly lower in those with noncirrhotic liver disease (88.5 +/- 41; P less than 0.02). The smallest continuous daily consumption leading to cirrhosis was 25,000 IU during 6 years, whereas higher daily doses (greater than or equal to 100,000 IU) taken during 21/2 years resulted in similar histological lesions. It was concluded that at least in some western countries chronic vitamin A consumption might represent an appreciable cause of chronic liver disease, the recognition of which mainly relies on expert liver biopsy interpretation. The data also indicate that prolonged and continuous consumption of doses in the low "therapeutic" range can result in life-threatening liver damage.     

Vitamin D modulates biliary fibrosis in ABCB4-deficient mice

Purpose

Impaired vitamin D receptor signaling represents an aggravating factor during liver injury, and recent studies suggest that vitamin D might exert a protective role in chronic hepatobiliary diseases. We hypothesized that vitamin D supplementation would ameliorate liver fibrosis in ATP-binding cassette transporter B4 knockout (Abcb4 ^?/?) mice as a preclinical model of sclerosing cholangitis.

Methods

Abcb4 ^?/? and wild-type mice were fed a regular chow diet (600 IU vitamin D/kg food) or diets with lower (100 IU/kg) and higher (2,400 IU/kg) vitamin D concentrations for 12 weeks. Serum 25-hydroxyvitamin D concentrations were measured by chemiluminescence immunoassays. Liver injury and biliary fibrosis were assessed by liver enzyme activities, histopathology and hepatic collagen contents. Hepatic mRNA expression of markers for fibrosis, vitamin D and bile acid metabolism were analyzed by quantitative PCR.

Results

Different vitamin D concentrations were observed depending on genotype and diet group, with Abcb4 ^?/? mice on the control diet showing lower vitamin D concentrations compared to wild-type mice. Abcb4 ^?/? animals on the low vitamin D diet demonstrated the most advanced liver fibrosis and highest hepatic collagen contents. Feeding Abcb4 ^?/? mice a high vitamin D diet enriched serum vitamin D levels, lowered liver enzyme activities, altered expression levels of profibrogenic genes and ameliorated, in part, liver injury.

Conclusions

This is the first report to demonstrate that fibrogenesis in the established Abcb4 ^?/? model is influenced by vitamin D supplementation. Since vitamin D modulates sclerosing cholangitis in vivo, we speculate that sufficient vitamin D intake might improve liver damage and induce antifibrotic effects in chronic cholestasis in humans.     

Vitamin D metabolism and osteomalacia in cystic fibrosis

A 25-yr-old black man with cystic fibrosis and cirrhosis developed symptoms of osteomalacia and hypocalcemia, hypophosphatemia, secondary hyperparathyroidism, and low circulating 25-hydroxyvitamin D (25-OHD). Serum 1,25-dihydroxyvitamin D (1,25-[OH]2D) was within the normal range. Iliac crest bone biopsy confirmed the diagnosis of osteomalacia. Oral administration of 50,000 IU of vitamin D2 failed to relieve symptoms or raise serum 25-OHD levels to normal. Intramuscular vitamin D2, 10,000 IU every 8-12 week, improved symptoms, raised serum 25-OHD to normal, and increased circulating 1,25-[OH]2D to values five times normal. Over the next 10 mo circulating 1,25-[OH]2D remained elevated despite normalization of serum calcium, phosphorus, and parathyroid hormone. Repeat bone biopsy 1 yr after parenteral vitamin D showed healing of the osteomalacia. Malabsorption of vitamin D appears secondary to profound steatorrhea due to pancreatic insufficiency and secondary biliary cirrhosis. Although extensive hepatocellular disease was present, hepatic conversion of vitamin D to 25-OHD was intact. Both high and low circulating 1,25-[OH]2D levels during active osteomalacia have been reported; initially, the level was in the normal range and higher values in this patient occurred with repletion of 25-OHD substrate. This study shows that symptomatic osteomalacia may be a major manifestation of cystic fibrosis in those patients surviving into adulthood. Measurements of serum 25-OHD in cystic fibrosis patients may identify those who should receive supplemental vitamin D.     

Retinyl-palmitate reduces liver fibrosis induced by biliary obstruction in rats

BACKGROUND/AIMS: The administration of retinoid in various experimental models of induced hepatic cirrhosis has shown antifibrogenic effects. The purpose of this study was to verify if vitamin A could interfere in hepatic fibrosis induced by biliary obstruction. METHODOLOGY: Male Wistar rats that underwent biliary obstruction were treated 2 weeks before the surgery with a dose of 50 x 10(3) IU retinyl-palmitate, twice a week, and then given the dosage for 5 weeks following surgery. They were then sacrificed and hepatic fragments removed to find out the biochemical dosage of hydroxyproline and the stereologic volume of collagen. Blood samples were also collected to find the biochemical dosage. RESULTS: The rats that underwent biliary obstruction and received vitamin A presented lower levels of hepatic hydroxyproline (p < 0.001) as well as a lower percentage of collagen tissue than the untreated control rats, but they presented higher AST and ALT serum levels (p < 0.05, p < 0.05). CONCLUSIONS: Under the above experimental conditions, the administration of vitamin A significantly reduced hepatic fibrosis.     

An unusual presentation of primary sclerosing cholangitis

This case report describes the unusual presentation of a patient who had findings which were initially suggestive of a type Ⅳ choledochal cyst. Her liver biopsy demonstrated biliary cirrhosis. She was treated with endoscopic retrograde cholangiopancreatography and biliary stent exchanges over one year. Her cholangiogram one year later demonstrated resolution of the biliary cystic dilation which led to her initial diagnosis, with beading and stricturing of the hepatic ducts consistent with primary sclerosing cholangitis. Liver-associated enzymes and physical findings also improved. A liver biopsy one year later demonstrated a marked improvement in hepatic fibrosis with no evidence of cirrhosis.     

Role of hepatic vitamin A and lipocyte distribution in experimental hepatic fibrosis

ABSTRACT— Lipocytes are the major site of hepatic vitamin A storage, and they have been demonstrated to lose their vitamin A content in the process of hepatic fibrosis. To investigate the relationship between hepatic vitamin A content and the degree of hepatic fibrosis, we measured levels of retinyl palmitate and retinol in the CCl₄-induced fibrotic liver using high-performance liquid chromatography. We estimated hepatic collagen content using a spectrophotometric analysis with sirius red, and also by measuring hydroxyproline levels. Lipocytes were detected by an immunoperoxidase method with anti-desmin antibody, and were counted morphometrically through a Texture Analyzing System. A significant negative correlation was observed between the level of retinyl palmitate and collagen content (r = –0.64) as well as the hydroxyproline level (r = –0.69) in the CCl₄-induced fibrotic liver. In the process of fibrosis, hepatic retinol levels were elevated in association with a decrease in retinyl palmitate. In particular in the early stage of fibrosis, lipocytes increased remarkably in number in fibrotic areas in spite of a decrease in total hepatic vitamin A. The present study suggests that an increase in hepatic retinol as well as a decrease in retinyl palmitate may facilitate the process of hepatic fibrosis produced by lipocytes.     

Hepatic fibrosis in rheumatoid arthritis patients treated with methotrexate: application of a new semi-quantitative scoring system

OBJECTIVE: Evaluation of hepatic lesions in patients treated with methotrexate (MTX) generally used the Roenigk histological score. However, the sensitivity of the method for hepatic fibrosis assessment has been discussed. The semi-quantitative histological scoring system (SSS) offers a sensitive and specific evaluation of liver fibrosis. Both scores have been evaluated in liver biopsies of patients with rheumatoid arthritis. METHODS: Seventy-four liver biopsies were obtained in 57 rheumatoid arthritis patients before initiation of MTX (group 1, 38 cases), in cases of a persistently high level of transaminases during 1 yr of treatment (group 2, 10 cases) and after a MTX total dose of 2 g (group 3, 26 cases). Eleven biopsies of groups 1 and 3 originated from the same patient in 11 cases. Specimens were examined blindly by two anatomopathologists. The three groups were compared with an ANOVA. Sequential biopsies performed in 11 patients were compared with the Wilcoxon paired test. RESULTS: The Roenigk score and the SSS were significantly correlated (P<0.0001). Only a mild fibrosis was found in 33.8% (25/74) of the biopsies with the Roenigk score. Liver fibrosis, graded as mild (48.6%), moderate (41.8%) or severe (4%), was demonstrated in 94.6% (70/74) of the biopsies with the SSS. The Roenigk score and the SSS of the three patient groups were not statistically significantly different. The scores did not progress in the 11 patients who had serial biopsies. CONCLUSION: SSS is much more sensitive than the Roenigk score for the evaluation of hepatic fibrosis. However, SSS did not show progression of hepatic fibrosis in patients with rheumatoid arthritis treated with MTX.     

Exposure to retinyl esters, retinol, and retinoic acids in non-pregnant women following increasing single and repeated oral doses of vitamin A

BACKGROUND: High intakes of vitamin A cause congenital malformations in experimental animals with elevated generation of retinoic acids (RA). Results in humans are conflicting. OBJECTIVE: To evaluate plasma concentration-time curves of retinyl esters, retinol and their metabolites at increasing doses of vitamin A. METHODS: An open-label dose-response study. Non-pregnant females (3 groups with n = 12; 18-40 years) received once daily oral doses of vitamin A palmitate up to 30,000 IU/day over 21 days. The area under the plasma concentration-time curve (AUC(24h)) served as indicator for exposure. RESULTS: AUC(24h) of retinyl esters increased linearly with dose. Retinol concentrations were unaffected. All-trans RA exhibited a diurnal-like concentration-time profile (Cmax at 3 h; Cmin at 8 h), concentrations decreasing below pre-dose levels at 5 h and regaining pre-dose levels at 16 h. The maximum temporary increase in exposure was 33% (single dose) and 19% (repeated doses) above baseline, but AUC(24h) remained unaltered. AUC(24h) increased linearly with dose for 13-cis RA and 13-cis-4-oxo RA. Repeated doses caused a 25% increase in exposure with the highest vitamin A intake. Accumulation of 13-cis-4-oxo RA at 30,000 IU/day doubled compared to the 4,000 IU/day intake. CONCLUSION: Repeated oral doses of up to 30,000 IU of vitamin A in addition to dietary vitamin A were without safety concern. Safe doses are probably higher, since plasma concentrations and exposure to RA remained at levels earlier shown to be without increased risk of teratogenicity in pregnant women.     

Consequences of defective vitamin A transportation on mitochondrial membrane integrity during protein depletion

The relationships between the structural integrity and functionality of rat liver mitochondrial membranes, and different levels of dietary protein and vitamin A transportation during protein depletion in animals have been investigated. Although the vitamin A content of the protein-depleted diet was 1680 +/- 35 IU/kg diet, and that of the control diet was 1,650 +/- 30 IU/kg diet, the vitamin A content of the liver of depleted rats was reduced to 16.7% of controls. The hepatic mitochondria of rats fed a protein-depleted diet showed excessive passive swelling (about 3-fold of controls) in isotonic solutions. Whereas a seemingly inverse relationship existed between the vitamin A content of the liver and the osmotic behaviour of hepatic mitochondria of rats fed a protein-depleted diet, there is a direct relationship between their hepatic mitochondrial vitamin A and the respiratory control ratio. The implications of these observations are discussed.     

High,but not low,dietary retinoids aggravate manifestation of rat liver fibrosis

BACKGROUND: Although there is strong implication that retinoids regulate Ito cell proliferation and collagen synthesis, results from in vivo studies on the relationship between vitamin A and liver fibrosis are conflicting. The present study focuses on the role of vitamin A in carbon tetrachloride (CCl4)-induced fibrosis by chronic feeding of rats with either a vitamin A-supplemented or -depleted diet. METHODS AND RESULTS: In animals with high dietary hepatic retinoid levels, liver fibrosis was more pronounced and was associated with an increased CCl4-toxicity resulting in high mortality (73%). Enhanced liver fibrosis was confirmed by in vivo fluorescence microscopic determination of both collagen deposits (7.4 +/- 1.1 vs 3.9 +/- 0.3% in high vitamin A diet-fed and standard diet-fed fibrotic animals, respectively; P < 0.05) and rarefication of sinusoids (1.5 +/- 0.2 vs 2.4 +/- 0.2 sinusoids/200 microm in high vitamin A diet-fed and standard diet-fed fibrotic animals, respectively; P < 0.05). It was further associated with decreased bile flow and increased parenchymal cell damage. CCl4 reduced hepatic retinoid levels in high vitamin A diet-fed animals, but restored hepatic retinoid levels in animals fed with a vitamin A-deficient diet, implying major interference of vitamin A metabolism with hepatotoxic agents such as CCl4. Low vitamin A feeding did not modulate liver fibrogenesis and caused no mortality. CONCLUSIONS: These results show that the vitamin A status of the liver plays an important role in liver fibrogenesis. While dietary vitamin A shortage does not promote liver fibrogenesis, high levels of vitamin A have the potential to increase systemic and hepatic toxicity of CCl4. Thus, the narrow therapeutic window for nutritional vitamin A substitution must take into account that liver fibrotic patients may display enhanced susceptibility to the adverse effects of vitamin A.     

Liver fibrosis in a patient with familial homozygous hypobetalipoproteinaemia: possible role of vitamin supplementation.

A case of apolipoprotein B-related disorder is reported in which liver fibrosis developed without long term administration of medium chain triglycerides, previously incriminated in the pathogenesis of this lesion. The patient was a young woman in whom the diagnosis of familial homozygous hypobetalipoproteinaemia was made at the age of 21. A first liver specimen taken at diagnosis revealed steatosis, hypertrophic Golgi apparatus and proliferating smooth endoplasmic reticulum. The patient was treated with vitamin A and E supplementation only. Two years later, a second liver biopsy, carried out because of increased serum alanine aminotransferase concentrations, showed fibrosis, mild cytolysis and marked mitochondrial alterations. Hepatic level of vitamin A was increased. This finding supports the hypothesis that liver disease observed in our patient might be an adverse effect of vitamin supplementation. Our observation underlines the importance of including liver function tests in the follow up of patients with apolipoprotein B-related disorders.     

Is the recommended daily allowance for vitamin D too low for the homebound elderly?

A population of sunlight-deprived elderly was studied to determine the daily intake of vitamin D and whether dietary intake was sufficient to maintain a normal vitamin D status. Twenty-two subjects over 65 years old with serum creatinine less than 180 mumols/L and confined indoors for more than 6 months were chosen from the community and a nursing home in Southeast Baltimore. Three-day food records were obtained along with serum levels of 25-hydroxyvitamin D (25-OHD), 1,25-dihydroxyvitamin D (1,25-(OH)2 D), and intact parathyroid hormone (PTH). The mean daily vitamin D intake was over twofold greater than the adult Recommended Daily Allowance (RDA) of 200 IU. The mean 25-OHD level was 40 nmol/L (normal 25-138 nmol/L) with seven patients less than 25 nmol/L. Of these participants with 25-OHD values less than 25 nmol/L, the mean vitamin D intake was 467 IU (range 36-1096 IU). We conclude that the current RDA seems inadequate for many older individuals who do not get sun exposure. This particular population of elderly is at risk to develop vitamin D deficiency and the associated complications.     

Liver in obesity.

We report on clinical, nutritional, and hepatic histological findings in 50 non-selected obese subjects (mean overweight +74%; range +21-138%). The pathogenesis of the liver damage was assessed with the help of multidimensional analysis of a number of clinical variables. According to the severity of the hepatic lesions, the patients have been ranged in five groups: O (normal liver) 10%; I (fatty liver) 48%; II (fatty hepatitis) 26%; III (fatty fibrosis) 8%; IV (fatty cirrhosis) 8%. The more severe changes (groups III and IV) were constantly associated with excessive alcohol intake. The multidimensional analysis was unable to find a relationship between obesity and the development of fibrosis and cirrhosis whereas it showed that: (a) there was a highly significant correlation between the daily ethanol intake and the degree of overweight, (b) severe fatty metamorphosis was significantly associated with the degree of overweight, the existence of diabetes mellitus, and the amount of alcohol and fat intake, (c) nutritional factors, in particular deficient protein intake, have only an accessory effect in the development of mild inflammation and fibrosis, (d) the consumption of potentially hepatotoxic drugs, very high in the obese (about five drugs per day) could have a role in the development of cirrhosis. In conclusion in our study, there was no evidence that obesity per se could result in severe liver damage.     

Large spleno-caval shunt not accompanied by cirrhosis or encephalopathy

A 40-year-old man with a large spleno-caval shunt through the azygos vein is described. This was considered a rare case, because the patient had no accompanying advanced liver disease, or episodes of hepatic encephalopathy. During checks after abnormal liver function test results, a shunt vessel was detected incidentally by ultrasonography. Computed tomography, magnetic resonance imaging, and angiography demonstrated that it was a large shunt between the splenic vein and superior vena cava through the coronary and azygos veins. The patient was a hepatitis B virus carrier and was positive for anti-HBe, and had a history of heavy drinking. However, on laparoscopic examination, the liver was not cirrhotic and the biopsy revealed only mild chronic hepatitis without bridging fibrosis. There were no esophageal varices or hepatosplenomegaly. On hemodynamic evaluation, the wedge hepatic vein pressure was slightly elevated and hepatic blood flow was reduced to half the normal value. Despite the large portal-systemic shunt, the patient had no history or signs of hepatic encephalopathy. The clinical features of this rare case are discussed.