Fat soluble vitamin deficiency in biliary atresia

Disturbed Vitamin A Metabolism in Non-Alcoholic Fatty Liver Disease (NAFLD)

Vitamin A is required for important physiological processes, including embryogenesis, vision, cell proliferation and differentiation, immune regulation, and glucose and lipid metabolism. Many of vitamin A’s functions are executed through retinoic acids that activate transcriptional networks controlled by retinoic acid receptors (RARs) and retinoid X receptors (RXRs).The liver plays a central role in vitamin A metabolism: (1) it produces bile supporting efficient intestinal absorption of fat-soluble nutrients like vitamin A; (2) it produces retinol binding protein 4 (RBP4) that distributes vitamin A, as retinol, to peripheral tissues; and (3) it harbors the largest body supply of vitamin A, mostly as retinyl esters, in hepatic stellate cells (HSCs). In times of inadequate dietary intake, the liver maintains stable circulating retinol levels of approximately 2 μmol/L, sufficient to provide the body with this vitamin for months. Liver diseases, in particular those leading to fibrosis and cirrhosis, are associated with impaired vitamin A homeostasis and may lead to vitamin A deficiency. Liver injury triggers HSCs to transdifferentiate to myofibroblasts that produce excessive amounts of extracellular matrix, leading to fibrosis. HSCs lose the retinyl ester stores in this process, ultimately leading to vitamin A deficiency. Non-alcoholic fatty liver disease (NAFLD) is the hepatic manifestation of metabolic syndrome and is a spectrum of conditions ranging from benign hepatic steatosis to non-alcoholic steatohepatitis (NASH); it may progress to cirrhosis and liver cancer. NASH is projected to be the main cause of liver failure in the near future. Retinoic acids are key regulators of glucose and lipid metabolism in the liver and adipose tissue, but it is unknown whether impaired vitamin A homeostasis contributes to or suppresses the development of NAFLD. A genetic variant of patatin-like phospholipase domain-containing 3 (PNPLA3-I148M) is the most prominent heritable factor associated with NAFLD. Interestingly, PNPLA3 harbors retinyl ester hydrolase activity and PNPLA3-I148M is associated with low serum retinol level, but enhanced retinyl esters in the liver of NAFLD patients. Low circulating retinol in NAFLD may therefore not reflect true “vitamin A deficiency”, but rather disturbed vitamin A metabolism. Here, we summarize current knowledge about vitamin A metabolism in NAFLD and its putative role in the progression of liver disease, as well as the therapeutic potential of vitamin A metabolites.

Fat-Soluble Vitamin Deficiency in Pediatric Patients with Biliary Atresia

Objective

To analyze the levels of fat-soluble vitamins (FSVs) in pediatric patients with biliary atresia (BA) before and after the Kasai procedure.

Methods

Pediatric patients with obstructive jaundice were enrolled in this study. The FSV levels and liver function before, 2 weeks after, and 1, 3, and 6 months after the Kasai procedure were measured.

Results

FSV deficiency was more obvious in patients with BA than in patients with other cholestatic liver diseases, especially vitamin D deficiency. 25-Hydroxy vitamin D (25-(OH)D) deficiency was more pronounced in younger patients before surgery. The 25-(OH)D level was significantly higher in patients with than without resolution of jaundice 3 months after surgery. At 6 months after surgery, the 25-(OH)D level was abnormally high at 8.76 ng/ml in patients with unresolved jaundice.

Conclusions

Preoperative FSV deficiency, particularly vitamin D deficiency, is common in patients with BA. 25-(OH)D deficiency is more pronounced in younger children before surgery. Postoperative FSV deficiency was still prevalent as shown by the lower 25-(OH)D levels in patients with BA and unresolved jaundice. This required long-term vitamin AD supplementation for pediatric patients with BA and unresolved jaundice after surgery.

Bone health in a nonjaundiced population of children with biliary atresia

Objectives. To assess bone health in a cohort of nonjaundiced children with biliary atresia (BA) and the effect of growth and development on bone outcomes. Methods. Children ages one to eighteen years receiving care from Children's Hospital of Philadelphia were recruited. Each child was seen once and assessed for growth, pubertal development, concurrent medications, bilirubin, ALT, albumin, vitamin D status, bone mineral density (BMD), and bone mineral content (BMC) of the lumbar spine and whole body. Results. BMD declined significantly with age, and upon further analysis with a well-phenotyped control cohort, it was found that BMC was significantly decreased for both lumbar spine and whole body, even after adjustment for confounding variables. An age interaction was identified, with older subjects having a significantly greater impairment in BMC. Conclusions. These preliminary results demonstrate that children with BA, including those without jaundice, are likely to have compromised bone health even when accounting for height and puberty, which are common confounding factors in chronic disease. Further investigation is needed to identify the determinants of poor bone mineral status and to develop strategies to prevent osteoporosis later in life.

Recent advances in biliary atresia: prospects for novel therapies

BACKGROUND

Biliary atresia (BA) is a progressive fibro-obliterative disease of the extrahepatic biliary tree that presents with biliary obstruction before 2 months of age. Untreated BA is a uniformly fatal disease and even with our current therapies only 50% of children with BA will be transplant-free by 2 years of age. Despite descriptions of this disorder dating back to the 1800s our current therapies are palliative. They focus on prompt diagnosis, supportive nutritional care and interventions for sequelae.

OBJECTIVE

To present the literature supporting current treatment strategies and potential future therapies.

METHOD

Each of the aspects of care is described and the literature about nuances of care is provided.

CONCLUSION

Therapies will not improve outcomes until novel treatments are introduced, such as those suggested, which may intervene in the inflammatory or fibrotic steps of the disease process.

Comparison of indices of vitamin A status in children with chronic liver disease

Malabsorption of fat-soluble vitamins is a major complication of chronic cholestatic liver disease. The most accurate way to assess vitamin A status in children who have cholestasis is unknown. The goal of this study was to assess the accuracy of noninvasive tests to detect vitamin A deficiency. Children with chronic cholestatic liver disease (n = 23) and noncholestatic liver disease (n = 10) were studied. Ten cholestatic patients were identified as vitamin A-deficient based on the relative dose response (RDR). Compared with the RDR, the sensitivity and specificity to detect vitamin A deficiency for each test was, respectively: serum retinol, 90% and 78%; retinol-binding protein (RBP), 40% and 91%; retinol/RBP molar ratio, 60% and 74%; conjunctival impression cytology, 44% and 48%; slit-lamp examination, 20% and 66%; tear film break-up time, 40% and 69%; and Schirmer's test, 20% and 78%. We developed a modified oral RDR via oral coadministration of d-alpha tocopheryl polyethylene glycol-1000 succinate and retinyl palmitate. This test had a sensitivity of 80% and a specificity of 100% to detect vitamin A deficiency. In conclusion, vitamin A deficiency is relatively common in children who have chronic cholestatic liver disease. Our data suggest that serum retinol level as an initial screen followed by confirmation with a modified oral RDR test is the most effective means of identifying vitamin A deficiency in these subjects.

Biliary atresia. A surgical perspective

The combination of portoenterostomy with subsequent liver transplantation is the treatment of choice for patients with biliary atresia. It is important, however, to attempt to keep the patient's own organ by continuing efforts to achieve the best possible results with portoenterostomy. Additional basic research, perhaps concerning on the role of cytokines and apoptosis in the control of biliary atresia, may provide insight into possible new medical strategies for treating patients with biliary atresia. For example, in addition to portoenterostomy, control of apoptosis at various cellular levels and of bile duct cell proliferation and maturation by manipulation of the growth factors and cytokines may become part of future treatment modalities. Another direction of research should be the control of fibrogenesis, which might be accomplished by blocking TGF-beta 1 and platelet-derived growth factor and by HGF gene therapy. The author's current strategy for surgical treatment for patients with biliary atresia include (1) early diagnosis, including prenatal diagnosis and broader use of mass screening programs, (2) hepatic portoenterostomy, without stoma formation; (3) close postoperative care, especially for prevention of postoperative cholangitis; (4) revision of portoenterostomy only in selected cases; (5) early liver transplantation in patients with absolutely failed portoenterostomy; (6) avoidance of laparotomy for the treatment of esophageal varices and hypersplenism; (7) consideration of exploratory laparotomy or primary liver transplantation for patients with advanced liver disease at the time of referral. The development of new treatment modalities based on the understanding of the pathogenesis of the disease, and especially on the biology of intrahepatic bile ducts and hepatic fibrosis, is essential.

Ocular abnormalities in Alagille syndrome

OBJECTIVE

To assess the type and frequency of ocular abnormalities occurring in Alagille syndrome (AS) in a large group of affected patients and their parents and the potential pathogenetic role of fat-soluble vitamin deficiency.

DESIGN

Observational case series.

PARTICIPANTS

Twenty-two children with AS and 23 of their parents participated.

MAIN OUTCOME MEASURES

Participants underwent full ophthalmic examination, including refraction, orthoptic examination, keratometry, slit-lamp examination, and funduscopy. Corneal diameter measurement was performed in a subset of nine and fluorescein angiography in a subset of six. Serum levels of vitamins A and E and cholesterol were measured.

RESULTS

The most common ocular abnormalities in patients with AS were posterior embryotoxon (95%), iris abnormalities (45%), diffuse fundus hypopigmentation (57%, a previously unreported finding), speckling of the retinal pigment epithelium (33%), and optic disc anomalies (76%). Microcornea was not associated with large refractive errors, and visual acuity was not significantly affected by these ocular changes. Vitamin levels were normal. Ocular abnormalities including posterior embryotoxon, iris abnormalities, and optic disc or fundus pigmentary changes were detected in one parent in 36% of cases.

CONCLUSIONS

Alagille syndrome is associated with a characteristic group of ocular findings without apparent serious functional significance and probably unrelated to fat-soluble vitamin deficiency. Simple ophthalmic examination of children with neonatal cholestatic jaundice and their parents should allow early diagnosis of AS, eliminating the need for extensive and invasive investigations.

Nutritional considerations and management of the child with liver disease

Nutritional management of the infant and child with liver disease is highly dependent upon the type of liver disease. Acute liver disease, such as that secondary to viral hepatitis, requires no specific nutritional therapy with the exception that branched-chain amino acid supplements may be indicated in the management of hepatic encephalopathy. Nutritional management of the child with chronic liver disease depends upon whether or not cholestasis is present, since in that condition, large amounts of fat-soluble vitamin supplements and medium-chain triglycerides are usually required for optimum growth. However, anicteric cirrhotic liver disease also presents nutritional challenges because of hypermetabolism, enteropathy, and increased protein oxidation. Certain inborn errors of metabolism that result in liver disease (including galactosemia, hepatorenal tyrosinemia, hereditary fructose intolerance, and Wilson's disease) have specific nutritional requirements. And, finally, the advent of pediatric liver transplantation has placed new emphasis on the importance of optimum nutritional management of the child with chronic liver disease, since improvement of nutritional status in the pretransplant period maximizes success of the transplant. This review will focus on the pathogenesis of malnutrition in childhood liver disease and will provide recommendations for nutritional assessment and monitoring as well as nutritional management of cholestatic liver disease, anicteric cirrhotic liver disease, and the inborn errors of metabolism enumerated above. Specific recommendations for nutritional management of the child awaiting liver transplantation will be provided.

Vitamin A status in biliary atresia: intestinal absorption and liver storage of retinol

The vitamin A status of 19 patients with corrected biliary atresia was examined. They had been receiving 5,000 IU of oral vitamin A daily postoperatively. Plasma vitamin A levels in the nonjaundiced group were almost within normal range, whereas those in the jaundiced group were significantly low compared with the controls. In the oral vitamin A tolerance test, plasma vitamin A levels increased from 33.1 +/- 11.8 to 215.4 +/- 100.7 micrograms/dL in the nonjaundiced group, and from 23.1 +/- 10.3 to 209.8 +/- 154.2 micrograms/dL in the slightly jaundiced group, at 4 hours after the administration of vitamin A, showing no difference between both group and control. In the severely jaundiced group, plasma vitamin A levels increased from 13.5 +/- 3.5 to 30.0 +/- 14.6 micrograms/dL, a significantly smaller increase compared with controls. However, liver vitamin A levels were greater than 20 micrograms/g liver in all patients, irrespective of the presence of jaundice. This study suggested that nutritional support to facilitate the synthesis of retinol-binding protein may be an important factor in addition to vitamin A supplementation.

Changes of lipid peroxide levels in blood and liver tissue of patients with obstructive jaundice

Plasma lipid peroxide levels, hereafter referred to as PLP levels, were measured in a group of 40 apparently healthy controls and 64 cholelithiasis patients, 40 with and 24 without jaundice. Hepatic lipid peroxide (HLP) levels were also measured in 26 patients, 15 with and 11 without jaundice. There was a significantly higher mean concentration of PLP in the jaundiced patients than in the control or jaundice-free cases. However, the difference in PLP levels between the jaundice-free and the control cases was insignificant. Meanwhile, patients with jaundice had significantly higher HLP levels than those without jaundice. In the jaundiced cases, the increased PLP and HLP levels were clearly related to the serum levels of bilirubin respectively. In addition, the HLP levels were positively correlated with the PLP levels; however, in the non-jaundiced cases, there was little evidence of these two relationships. Patients with or without jaundice had lower plasma vitamin E levels in comparison to the control cases. The correlation of plasma vitamin E and PLP levels was weak in all of the jaundiced. However, when we subdivided the jaundiced into two groups, the correlation was strong in those with plasma vitamin E levels < 8.5 micrograms/ml, while the correlation was weak in those with plasma vitamin E levels > 8.5 micrograms/ml. Consequently, these results suggest that there is an involvement of lipid peroxidation in liver cells damaged by obstructive jaundice in cholelithiasis patients and there exists a negative correlation between low vitamin E and lipid peroxide levels in plasma.

Bone mineral analysis and X-ray examination of the bone in patients with biliary atresia

Investigations of bone mineral content, X-ray of the radius and ulna and serum biochemical analysis were performed in 10 children with biliary atresia (B.A.) and 150 healthy children. The patients were classified into 2 groups, namely; group A, comprised of 5 patients whose postoperative courses went well, and group B, comprised of 5 patients who developed various degrees of liver disturbance postoperatively. The ratio of bone mineral content (BMC) to bone width (BW) (BMC/BW) increased in accordance with age in the healthy children and the patients of group A, but was relatively slow in the patients of group B. Signs of rickets were found on the X-rays of 4 of the 10 patients, while serum levels of calcium and 25-OH-vitamin D in the group B patients were significantly lower than those in the group A patients or healthy children. Serum levels of alkaline phosphatase (Alp) fluctuated, but serum Alp was elevated in all the patients with rickets.

Nutritional support for the infant with extrahepatic biliary atresia

Some infants with biliary atresia obtain dramatic improvement for prolonged periods after the performance of hepatic portoenterostomy. Such infants may have life styles not substantially different from those of normal children. In others, the benefit from this operation, if any, is short lived. These infants are very vulnerable to the debilitating effects of severe, prolonged malabsorption and ultimately require orthotopic liver transplantation to sustain life. The physician caring for infants awaiting liver transplantation can do much, not only to prolong survival but to maintain satisfactory growth and development. The key consideration is to provide adequate nitrogen and nonnitrogen calories, liberally utilizing modern methods of enteral alimentation when necessary. In addition, attention must be directed toward several vitamin and mineral deficiencies, particularly those of the fat-soluble vitamins, that inevitably accompany severe malabsorption in children. Management of extrahepatic biliary atresia in infants is difficult and requires meticulous attention to details. Nevertheless, the long-term cure of this disorder provided by liver transplantation makes their care a rewarding experience.

Biochemical indicators of vitamin A depletion in children with cholestasis

Biochemical indicators of vitamin A status were measured in 24 children (1 month to 6 years old) with severe cholestasis starting early in life and in 21 children (3 months to 13 years old) with liver disease but without cholestasis. Liver vitamin A concentrations, expressed as micrograms of retinol per gram of liver (mean +/- S.D.), were 6.3 +/- 7.1 (range: 0.14 to 28) and 143 +/- 108 (range: 18 to 424), respectively, in cholestatic and non-cholestatic children. In infants less than 6 months of age, liver vitamin A values less than 10 micrograms per gm were found in 14 of 17 cholestatic children but in none of 3 non-cholestatic subjects. Plasma vitamin A values, expressed as micrograms of retinol per deciliter (mean +/- S.D.), were 23 +/- 18 (range: 3 to 62) and 46 +/- 33 (range: 14 to 125), respectively, for the two groups. Plasma retinol values less than 10 micrograms per dl were always associated with liver concentrations less than 10 micrograms per gm. Plasma retinol-binding protein was only reduced to 71% of control values in cholestatic children. The fatty acid composition of liver retinyl esters was unaffected by any condition studied. Infants with chronic cholestasis are in a precarious nutritional status very early in life relative to liver reserves of vitamin A. Plasma vitamin A values, unless less than 10 micrograms retinol per dl, are poor indicators of inadequate vitamin A status.

Contemporary surgery of biliary atresia

The etiology of biliary atresia is not due to a congenital malformation but rather to a continuing process beginning in utero that affects not only the extrahepatic biliary ducts but also the intrahepatic parenchyma. Over the last decade, the outlook for patients who were previously felt to be uncorrectable has been significantly improved by Kasai's operation. Successful biliary reconstruction depends on early diagnosis and treatment (before three months of age). The essentials of hepatic portoenterostomy consist of excision of the entire extrahepatic duct structure with anastomosis of an intestinal conduit to the area of the transected duct at the liver hilus. After operation, many patients experience complications, including cholangitis, portal hypotension, and vitamin deficiencies. Despite these difficulties, growth and development continue on a relatively normal course, and long-term survival has been accomplished in many children. For those in whom biliary drainage is not achieved or with significant parenchymal damage, liver transplantation should be considered as part of ongoing care.

Analysis of patients with biliary atresia coming to liver transplantation

Seventy-two patients with end-stage liver disease underwent liver transplantation between March 1981 and March 1984; 35 (49%) with biliary atresia, the remainder with other disorders. This provided us with a unique opportunity to analyze factors leading to liver failure in patients who had undergone biliary drainage procedures for "uncorrectable" biliary atresia. Four patients in the biliary atresia group were excluded (no corrective procedure done, 3; "correctable" biliary atresia, 1), leaving 31 patients for study. Transplantation survival was 84% for the study group and 73% in children with other primary liver disorders. Most patients were less than 3 months old at the time of initial surgery, had minimal liver disease, and had accepted corrective operations by experienced surgeons. Despite these "favorable" factors, bile drainage was rarely achieved. All patients with continued bile drainage at the time of transplantation had repeated episodes of cholangitis, and cholangitis was associated with cessation of bile drainage in half of those with transient function. Findings at hepatectomy suggested that in four cases where bile drainage was never achieved, reexploration may have been successful. Complications included those associated with hepatic failure and portal hypertension. Of note were a high incidence of bone disease and a 43% incidence of stomal hemorrhage in patients with stomas. The short-term survival after transplantation was comparable in the biliary atresia group and the children with other disorders. This suggests that while the presence of a previous biliary drainage procedure may increase the technical difficulty of transplantation, it does not decrease survival.

The multiple coagulopathies of biliary atresia

Detailed coagulation studies were done prospectively on 43 patients with biliary atresia who had undergone Kasai operation (hepatic portoenterostomy). Patients were divided into three groups based on levels of factor V, factor II, and Echis II and/or response to vitamin K: no coagulopathy (46.5% of patients); coagulopathy of liver disease (30.2% of patients); and coagulopathy of vitamin K deficiency (23.3% of patients). Patients with the coagulopathy of liver disease had significantly lower levels of factors XII, V, and antithrombin III as well as longer thrombin times than patients with no coagulopathy or vitamin K deficiency. Factor V levels were decreased only in patients with more advanced liver disease; normal levels of factor V were not usually helpful in differentiating liver disease and vitamin K deficiency. The prothrombin time, factor VII-X levels, and factor II levels were significantly different for all three groups; the most abnormal values occurred in the vitamin K-deficient group. Comparison of the Echis II level to factor II coagulant activity was helpful in deciding whether a coagulopathy was due to liver disease, vitamin K deficiency, or both. Factor VIII levels were elevated in all groups. Factor VIII coagulant activity was significantly higher by the two-stage (TGT) method than by the one-stage (PTT) method. Hypersplenism causing neutropenia and thrombocytopenia was commonly seen after the age of 5 years. Vitamin E deficiency was more common than vitamin K deficiency; however, all vitamin K-deficient patients were vitamin E deficient. Coagulation status correlated well with hepatobiliary scan data, but not serum bilirubin levels. Recommendations for treatment of patients with vitamin K deficiency and/or liver disease are discussed.

Cholestasis in infancy and childhood

Many disorders are capable of producing cholestasis in infancy. Primary hepatobiliary diseases and systemic infectious, toxic, and metabolic insults may present clinically as conjugated hyperbilirubinemia. A careful, organized diagnostic evaluation allows early identification of potentially treatable lesions. Recent success in the surgical management of biliary atresia, previously a uniformly fatal disorder, has emphasized the need for early diagnosis. Medical management of the complications of chronic cholestasis remains a major challenge. Liver transplantation currently offers the only chance for long-term survival for infants with progressive cirrhosis.

Improved results with hepatic portoenterostomy: a reassessment of its value in the treatment of biliary atresia

As reported in 1974, the initial experience at the Oklahoma Children's Memorial Hospital with the Kasai procedure for biliary atresia was unsatisfactory. A subsequent series of 20 patients, in which 50% of the patients are alive and improved and 25% jaundice-free, is described. Modifications of the initial operative technique have been utilized. Postoperative complications in the ten children with sustained bile flow included cholangitis in five, hyponatremia in four, esophageal variceal hemorrhage in two, stomal bleeding in two, and gallbladder conduit malfunction in two patients. The improved outcome is attributed to earlier diagnosis and correction, attention to operative details, intensive postoperative nutritional support, and prompt recognition and management of complications.