Patient and graft survival after liver transplantation for hereditary hemochromatosis: Implications for pathogenesis

HFE-Related Hemochromatosis May Be a Primary Kupffer Cell Disease

Iron overload can lead to increased deposition of iron and cause organ damage in the liver, the pancreas, the heart and the synovium. Iron overload disorders are due to either genetic or acquired abnormalities such as excess transfusions or chronic liver diseases. The most common genetic disease of iron deposition is classic hemochromatosis (HH) type 1, which is caused by mutations of HFE. Other rare forms of HH include type 2A with mutations at the gene hemojuvelin or type 2B with mutations in HAMP that encodes hepcidin. HH type 3, is caused by mutations of the gene that encodes transferrin receptor 2. Mutations of SLC40A1 which encodes ferroportin cause either HH type 4A or HH type 4B. In the present review, an overview of iron metabolism including absorption by enterocytes and regulation of iron by macrophages, liver sinusoidal endothelial cells (LSECs) and hepatocyte production of hepcidin is presented. Hereditary Hemochromatosis and the current pathogenetic model are analyzed. Finally, a new hypothesis based on published data was suggested. The Kupffer cell is the primary defect in HFE hemochromatosis (and possibly in types 2 and 3), while the hepcidin-relative deficiency, which is the common underlying abnormality in the three types of HH, is a secondary consequence.

Tumour stemness and poor clinical outcomes in haemochromatosis patients with hepatocellular carcinoma

AIMS

Patients with haemochromatosis (HFE) are known to have an increased risk of developing hepatocellular carcinoma (HCC). Available data are conflicting on whether such patients have poorer prognosis, and there is lack of data regarding the biology of HFE-HCC. We compared the course of HFE-HCC with a matched non-HFE-HCC control group and examined tumour characteristics using immunohistochemistry.

METHODS

In this tertiary care-based retrospective analysis, 12 patients with HFE and 34 patients with alcohol/non-alcoholic steatohepatitis who underwent initially successful curative HCC therapy with ablation or resection were identified from our registry. Time to tumour progression was compared. Resected liver tissue from a separate cohort of 11 matched patients with HFE-HCC and without HFE-HCC was assessed for the expression of progenitor and epithelial-mesenchymal transition markers using immunohistochemistry.

RESULTS

The median follow-up was 24.39 and 24.28 months for patients with HFE-HCC and those without HFE-HCC, respectively (p>0.05). The mean time to progression was shorter in the HFE group compared with the non-HFE group (12.87 months vs 17.78 months; HR 3.322, p<0.05). Patients with HFE-HCC also progressed to more advanced disease by the end of follow-up (p<0.05). Immunohistochemical analysis of matched HFE-HCC and non-HFE-HCC explants demonstrated increased expression of the cancer stem cell markers EpCAM (epithelial cell adhesion molecule) and EpCAM/SALL4 (spalt-like transcription factor 4) coexpression in HFE-HCC specimens (p<0.05). There was a high frequency of combined tumour subtypes within the HFE cohort.

CONCLUSIONS

This study demonstrates that the clinical course of patients with HFE-HCC is more aggressive and provides the first data indicating that their tumours have increased expression of progenitor markers. These findings suggest patients with HFE-HCC may need to be considered for transplant at an earlier stage.

A Rare Case of Hereditary Hemochromatosis Presenting As Hyperbilirubinemia

Hemochromatosis is a condition marked by excessive iron accumulation, causing dysfunction in various organs. A 50-year-old woman, previously in good health, reported abdominal pain and yellowing of the skin and eyes for one month. Upon examination, she exhibited widespread jaundice, leg swelling, and abdominal distention. Her total bilirubin level was 24.52 mg/dL at admission, indicating hyperbilirubinemia. Imaging studies, including USG and CT scans, revealed mild to moderate ascites and altered liver texture. Elevated serum ferritin (1443 ng/mL) and transferrin saturation (84%) suggested iron overload. A liver biopsy confirmed the presence of iron deposits in hepatocytes, leading to a diagnosis of hemochromatosis. Genetic testing was negative for the C282Y and H63D mutations, resulting in a diagnosis of non-homeostatic iron regulator (non-HFE) related hereditary hemochromatosis. The patient began weekly phlebotomy and was monitored regularly, with a liver transplant being considered as a potential treatment.

Haemochromatosis

Haemochromatosis is one of the most common genetic diseases affecting patients of northern European ancestry. It is overdiagnosed in patients without iron overload and is underdiagnosed in many patients. Early diagnosis by genetic testing and therapy by periodic phlebotomy can prevent the most serious complications, which include liver cirrhosis, liver cancer, and death. This Seminar includes an update on the origins of haemochromatosis; and an overview pathophysiology, genetics, natural history, signs and symptoms, differential diagnoses, treatment with phlebotomy, outcomes, and future directions.

Long-term outcomes and trends in liver transplantation for hereditary hemochromatosis in the United States

There have been conflicting data regarding liver transplantation (LT) outcomes for hereditary hemochromatosis (HH), with no recent data on LT outcomes in patients with HH in the past decade. Using the United Network for Organ Sharing registry, we evaluated waitlist and post-LT survival in all adult patients listed for HH without concomitant liver disease from 2003 to 2019. Post-LT survival for HH was compared with a propensity-matched (recipient and donor factors) cohort of recipients with chronic liver disease (CLD). From 2003 to 2019, 862 patients with HH were listed for LT, of which 55.6% ( n = 479) patients underwent LT. The 1- and 5-year post-LT survival rates in patients with HH were 88.7% (95% confidence interval [CI], 85.4%-91.4%) and 77.5% (95% CI, 72.8%-81.4%), respectively, and were comparable with those in the propensity-matched CLD cohort ( p value = 0.96). Post-LT survival for HH was lower than for Wilson's disease, another hereditary metabolic liver disease with similar LT volume ( n = 365). Predictors for long-term (5-year) post-LT mortality included presence of portal vein thrombosis (hazard ratio [HR], 1.96; 95% CI, 1.07-3.58), obesity measurements greater than Class II (HR, 1.98; 95% CI, 1.16-3.39), and Karnofsky performance status (HR, 0.98; 95% CI, 0.97-0.99) at the time of LT. The leading cause of post-LT death ( n = 145) was malignancy (25.5%), whereas cardiac disease was the cause in less than 10% of recipients. In conclusion, short- and long-term survival rates for HH are excellent and comparable with those of other LT recipients. Improving extrahepatic metabolic factors and functional status in patients with HH prior to LT may improve outcomes.

Postoperative Complications in Patients With Hereditary Hemochromatosis Undergoing Total Joint Arthroplasty: A Matched Cohort Analysis

AIMS

The purpose of this study is to determine differences in the rates of 90-day postoperative complications and 2- and 5-year surgical outcomes between patients with and without hereditary hemochromatosis (HH) after total joint arthroplasty (TJA).

METHODS

Patients who underwent primary total hip arthroplasty (THA) or total knee arthroplasty (TKA) from 2010 to 2018 were identified in a national database (PearlDiver Technologies) using Current Procedural Terminology and International Classification of Diseases-9/10 codes. Patients with a history of HH were identified within the THA and TKA cohorts and matched with non-HH patients based on age, sex, Charlson Comorbidity Index, smoking status, and obesity (body mass index > 30). Ninety-day medical complications assessed included renal failure, arrhythmia, bleeding complications, blood transfusion, pneumonia, stroke, deep vein thrombosis, liver failure, heart failure, pulmonary embolism, sepsis, surgical site infection, wound dehiscence, readmission rate, and death. Two- and 5-year surgical complications assessed included all-cause revision, prosthetic joint infection, implant loosening, joint stiffness, and manipulation under anesthesia. All complications were analyzed using bivariate analysis and logistic regression, with significance set at P < 0.05.

RESULTS

Compared with non-HH patients, patients with HH had higher rates of stiffness at 2 and 5 years after THA (all, P < 0.001), as well as higher rates of aseptic loosening at 5 years after TKA (P = 0.036). However, patients with HH undergoing THA and TKA had no notable difference in 90-day postoperative complications when compared with non-HH patients.

DISCUSSION

Compared with non-HH patients, patients with HH undergoing TJA were shown to have worse 2- and 5-year surgical outcomes, without any increased risk of 90-day medical complications. These findings may be useful for surgical decision making for patients with HH undergoing TJA.

CLINICAL RELEVANCE

This study addresses a paucity in the current literature concerning the complication profile in HH patients with destructive joint arthropathy undergoing joint arthroplasty surgery.

Combined heart-liver transplantation in a case of haemochromatosis

Hereditary haemochromatosis results in multiorgan dysfunction secondary to iron overload. Haemojuvelin (HJV)-associated haemochromatosis, is a rapidly progressing form of haemochromatosis caused by mutation in the HJV that frequently results in heart and liver failure. Herein, we describe the successful treatment of a 39-year-old woman with decompensated heart failure and liver cirrhosis requiring extracorporeal membrane oxygenation who was successfully treated with combined heart-liver transplantation. Following her life-saving multiorgan transplantation, she was also noted to have rapid correction of her serum ferritin to normal levels. She remains healthy with excellent allograft function and normal iron and ferratin levels 4 years after the procedure. To our knowledge, this case is the first demonstration that combined heart-liver transplantation is a feasible option for patients with heart and liver failure secondary to HJV-associated haemochromatosis and indeed offers a long-standing corrective solution to treat this condition and restore physiologically normal iron metabolism.

Long-term Outcome of Orthotopic Liver Transplantation in Patients With Hemochromatosis: A Summary of a 30-year Transplant Program

Hemochromatosis (HC) is an autosomal recessive disease characterized by impaired iron metabolism and a rare indication for orthotopic liver transplantation (LT). Data about iron reaccumulation and remodeling of the liver graft after LT are limited. Therefore, we performed an evaluation of the histopathologic changes during long-term follow-up in patients with HC.

Iron metabolism imbalance at the time of listing increases overall and infectious mortality after liver transplantation

BACKGROUND

Liver transplantation (LT) is the best treatment for patients with liver cancer or end stage cirrhosis, but it is still associated with a significant mortality. Therefore identifying factors associated with mortality could help improve patient management. The impact of iron metabolism, which could be a relevant therapeutic target, yield discrepant results in this setting. Previous studies suggest that increased serum ferritin is associated with higher mortality. Surprisingly iron deficiency which is a well described risk factor in critically ill patients has not been considered.

AIM

To assess the impact of pre-transplant iron metabolism parameters on post-transplant survival.

METHODS

From 2001 to 2011, 553 patients who underwent LT with iron metabolism parameters available at LT evaluation were included. Data were prospectively recorded at the time of evaluation and at the time of LT regarding donor and recipient. Serum ferritin (SF) and transferrin saturation (TS) were studied as continuous and categorical variable. Cox regression analysis was used to determine mortality risks factors. Follow-up data were obtained from the local and national database regarding causes of death.

RESULTS

At the end of a 95-mo median follow-up, 196 patients were dead, 38 of them because of infections. In multivariate analysis, overall mortality was significantly associated with TS > 75% [HR: 1.73 (1.14; 2.63)], SF < 100 µg/L [HR: 1.62 (1.12; 2.35)], hepatocellular carcinoma [HR: 1.58 (1.15; 2.26)], estimated glomerular filtration rate (CKD EPI Cystatin C) [HR: 0.99 (0.98; 0.99)], and packed red blood cell transfusion [HR: 1.05 (1.03; 1.08)]. Kaplan Meier curves show that patients with low SF (< 100 µg/L) or high SF (> 400 µg/L) have lower survival rates at 36 mo than patients with normal SF (P = 0.008 and P = 0.016 respectively). Patients with TS higher than 75% had higher mortality at 12 mo (91.4% ± 1.4% vs 84.6% ± 3.1%, P = 0.039). TS > 75% was significantly associated with infection related death [HR: 3.06 (1.13; 8.23)].

CONCLUSION

Our results show that iron metabolism imbalance (either deficiency or overload) is associated with post-transplant overall and infectious mortality. Impact of iron supplementation or depletion should be assessed in prospective study.

ACG Clinical Guideline: Hereditary Hemochromatosis

Hereditary hemochromatosis (HH) is one of the most common genetic disorders among persons of northern European descent. There have been recent advances in the diagnosis, management, and treatment of HH. The availability of molecular diagnostic testing for HH has made possible confirmation of the diagnosis for most patients. Several genotype-phenotype correlation studies have clarified the differences in clinical features between patients with the C282Y homozygous genotypes and other HFE mutation patterns. The increasing use of noninvasive tests such as MRI T2* has made quantification of hepatic iron deposition easier and eliminated the need for liver biopsy in most patients. Serum ferritin of <1,000 ng/mL at diagnosis remains an important diagnostic test to identify patients with a low risk of advanced hepatic fibrosis and should be used routinely as part of the initial diagnostic evaluation. Genetic testing for other types of HH is available but is expensive and generally not useful in most clinical settings. Serum ferritin may be elevated among patients with nonalcoholic fatty liver disease and in those with alcoholic liver disease. These diagnoses are more common than HH among patients with elevated serum ferritin who are not C282Y homozygotes or C282Y/H63D compound heterozygotes. A secondary cause for liver disease should be excluded among patients with suspected iron overload who are not C282Y homozygotes. Phlebotomy remains the mainstay of therapy, but emerging novel therapies such as new chelating agents may have a role for selected patients.

Hepatic Iron Overload following Liver Transplantation from a C282Y/H63D Compound Heterozygous Donor

Hereditary hemochromatosis (HH) is a genetic disease associated with progressive iron overload, eventually leading in some cases to damage of parenchymal organs, such as the liver, pancreas, and heart. Although the gene had been identified (HFE), HH pathogenesis remains to be fully elucidated. We report here, for the first time, a case of inadvertent transplantation of a liver from a donor with C282Y/H63D compound heterozygosity into a nonhemochromatotic 19-year-old Caucasian male recipient with primary sclerosing cholangitis. Progressive iron overload occurred over 1.5 years, as observed in liver biopsies and iron studies, after ruling out secondary causes of iron overload. This case strengthens the hypothesis that the liver, rather than the small intestine, plays a primary role in the maintenance of iron homeostasis.

Haemochromatosis

Haemochromatosis is defined as systemic iron overload of genetic origin, caused by a reduction in the concentration of the iron regulatory hormone hepcidin, or a reduction in hepcidin-ferroportin binding. Hepcidin regulates the activity of ferroportin, which is the only identified cellular iron exporter. The most common form of haemochromatosis is due to homozygous mutations (specifically, the C282Y mutation) in HFE, which encodes hereditary haemochromatosis protein. Non-HFE forms of haemochromatosis due to mutations in HAMP, HJV or TFR2 are much rarer. Mutations in SLC40A1 (also known as FPN1; encoding ferroportin) that prevent hepcidin-ferroportin binding also cause haemochromatosis. Cellular iron excess in HFE and non-HFE forms of haemochromatosis is caused by increased concentrations of plasma iron, which can lead to the accumulation of iron in parenchymal cells, particularly hepatocytes, pancreatic cells and cardiomyocytes. Diagnosis is noninvasive and includes clinical examination, assessment of plasma iron parameters, imaging and genetic testing. The mainstay therapy is phlebotomy, although iron chelation can be used in some patients. Hepcidin supplementation might be an innovative future approach.

Genetic, hematological, and immunological disorders transmissible with liver transplantation

It is well recognized that solid organ transplantation can transmit bacterial infection and chronic viral hepatitis as well as certain cancers. As indications for liver transplantation (LT) have expanded, it has been used to treat and even cure certain genetic cholestatic disorders, urea cycle defects, and coagulation abnormalities; many of these conditions are potentially transmissible with LT as well. It is important for clinicians and transplant patients to be aware of these potentially transmissible conditions as unexplained post-LT complications can sometimes be related to donor transmission of disease and thus should prompt a thorough exploration of the donor allograft history. Herein, we will review the reported genetic, metabolic, hematologic, and immunological disorders that are transmissible with LT and describe clinical scenarios in which these cases have occurred, such as in inadvertent or recognized transplantation of a diseased organ, domino transplantation, and with living related liver donation. Liver Transplantation 23 663-678 2017 AASLD.

Haemochromatosis

Haemochromatosis is now known to be an iron-storage disease with genetic heterogeneity but with a final common metabolic pathway resulting in inappropriately low production of the hormone hepcidin. This leads to increase in intestinal absorption and deposition of excessive amounts of iron in parenchymal cells which in turn results in eventual tissue damage and organ failure. A clinical enigma has been the variable clinical expression with some patients presenting with hepatic cirrhosis at a young age and others almost asymptomatic for life. Research is unravelling this puzzle by identifying environmental factors-especially alcohol consumption-and associated modifying genes that modulate phenotypic expression. A high index of suspicion is required for early diagnosis but this can lead to presymptomatic therapy and a normal life expectancy. Venesection (phlebotomy) therapy remains the mainstay of therapy, but alternative therapies are the subject of current research.

Liver transplantation in Australia and New Zealand

Liver transplantation (LT) in Australia and New Zealand began in 1985. Over this time until December 2014, LT took place in 3700 adults and 800 children. LT is regulated with 1 unit, supported by the government, per state or region. Currently approximately 270 transplants take place per year. Organ donation rates are moderate in Australia (17 per 1 million of population) but very low in New Zealand (11 per 1 million of population). All the units share organ donors for fulminant hepatic failure cases (status 1). Recipient listing criteria and organ allocation criteria are commonly agreed to via National and Trans-Tasman agreements, which are published online. Current survival rates indicate approximately 94% 1-year survival with median survival in adults of approximately 20 years, whereas 75% of children are alive at 20 years. All units collaborate in research projects via the Australia and New Zealand Liver Transplant Registry and have published highly cited articles particularly on the prevention of hepatitis B virus recurrence. Outcomes for indigenous populations have also been analyzed. In conclusion, LT in Australia and New Zealand is well developed with transparent processes related to criteria for listing and organ allocation together with publication of outcomes. Liver Transplantation 22 830-838 2016 AASLD.

Liver transplantation using grafts with rare metabolic disorders

Metabolic diseases that involve the liver represent a heterogeneous group of disorders. Apart from the metabolic defect, the subject's liver functions may be normal. With the increasing need for organs, livers from donors with metabolic diseases other than familial amyloid polyneuropathy might be possibly used for transplantation. However, whether such livers qualify as grafts and how they might impact recipient outcome are still unanswered questions. This review of the literature summarizes current experience in the use of such grafts in the context of cadaveric, domino, and living-related liver transplantation.

Adult liver disorders caused by inborn errors of metabolism: review and update

Inborn errors of metabolism (IEMs) are a group of genetic diseases that have protean clinical manifestations and can involve several organ systems. The age of onset is highly variable but IEMs afflict mostly the pediatric population. However, in the past decades, the advancement in management and new therapeutic approaches have led to the improvement in IEM patient care. As a result, many patients with IEMs are surviving into adulthood and developing their own set of complications. In addition, some IEMs will present in adulthood. It is important for internists to have the knowledge and be familiar with these conditions because it is predicted that more and more adult patients with IEMs will need continuity of care in the near future. The review will focus on Wilson disease, alpha-1 antitrypsin deficiency, citrin deficiency, and HFE-associated hemochromatosis which are typically found in the adult population. Clinical manifestations and pathophysiology, particularly those that relate to hepatic disease as well as diagnosis and management will be discussed in detail.

Iron metabolism in transplantation

Recipient's iron status is an important determinant of clinical outcome in transplantation medicine. This review addresses iron metabolism in solid organ transplantation, where the role of iron as a mediator of ischemia-reperfusion injury, as an immune-modulatory element, and as a determinant of organ and graft function is discussed. Although iron chelators reduce ischemia-reperfusion injury in cell and animal models, these benefits have not yet been implemented into clinical practice. Iron deficiency and iron overload are associated with reduced immune activation, whose molecular mechanisms are reviewed in detail. Furthermore, iron overload and hyperferritinemia are associated with poor prognosis in end-stage organ failure in patients awaiting kidney, or liver transplantation. This negative prognostic impact of iron overload appears to persist after transplantation, which highlights the need for optimizing iron management before and after solid organ transplantation. In contrast, iron deficiency and anemia are also associated with poor prognosis in patients with end-stage heart failure. Intravenous iron supplementation should be managed carefully because parenterally induced iron overload could persist after successful transplantation. In conclusion, current evidence shows that iron overload and iron deficiency are important risk factors before and after solid organ transplantation. Iron status should therefore be actively managed in patients on the waiting list and after transplantation.

The association of pretransplant ferritin level with waiting list and post-transplant survival. Does ferritin actually predict outcome?

Recent data suggest an association of serum ferritin (SF) with waiting list (WL) and postliver transplant (LT) outcomes. To assess the predictive capacity of SF on pre- and post-LT outcomes, and to identify whether recipient or donor liver siderosis is associated with post-LT survival; a retrospective analysis of 1079 patients assessed for first LT, 2000-2007 was performed. Iron deposition in the liver tissue was assessed using a semi-quantitative grading system. Median age was 54 (18-82) years and 67% were male. Seventeen per cent had hepatocellular carcinoma (HCC). Median Model for End-stage Liver Disease MELD score was 14 (6-40), ferritin was 174 μg/l (4-4597) with 36.5% had a SF ≥ μg/l. Age (OR = 1.028) and MELD score (OR = 1.158) were independently associated with WL mortality (P < 0.001), whilst SF was not (P = NS). Age (OR = 1.018), HCC (OR = 1.542) and cold ischemia time (CIT) ≥ 10 h (OR = 1.418) were independently associated with post-LT survival (P < 0.05). Explant siderosis grade <2 was seen in 376 (71.7%) patients. Patients with explant siderosis grade ≥ 2 had inferior 12-month post-LT survival (P = 0.030). Presence of graft siderosis (15.8% of patients) was not associated with survival. In conclusion, we found a limited role for SF as a prognostic indicator for pre- or post-transplant survival.

Care of the liver transplant patient

OBJECTIVE

To provide an approach to the care of liver transplant (LT) patients, a growing patient population with unique needs.

METHODS

A literature search of PubMed for guidelines and review articles using the keywords "liver transplantation", "long term complications" and "medical management" was conducted, resulting in 77 articles.

RESULTS

As a result of being on immunosuppression, LT recipients are at increased risk of infections and must be screened regularly for metabolic complications and malignancies.

DISCUSSION

Although immunosuppression is key to maintaining allograft health after transplantation, it comes with its own set of medical issues to follow. Physicians following LT recipients must be aware of the greater risk for hypertension, diabetes, dyslipidemia, renal failure, metabolic bone disease and malignancies in these patients, all of whom require regular monitoring and screening. Vaccination, quality of life, sexual function and pregnancy must be specifically addressed in transplant patients.

Liver transplantation normalizes serum hepcidin level and cures iron metabolism alterations in HFE hemochromatosis

Defects in human hemochromatosis protein (HFE) cause iron overload due to reduced hepatic hepcidin secretion. Liver transplantation (LT) is a key treatment for potential complications from HFE-related hereditary hemochromatosis (HH). This study evaluated hepcidin secretion and iron burden after LT to elucidate HH pathophysiology. Patients (n=18) homozygous for the p.Cys282Tyr mutation in the HFE gene underwent LT between 1999 and 2008. Serum iron, serum hepcidin, and hepatic iron concentrations were determined before LT and at the end of follow-up (median 57 months). Mortality and causes of death were determined. Survival was compared to that of the overall patient population that received LT. Before LT, serum hepcidin levels were low (0.54 ± 2.5 nmol/L; normal range: 4-30 nmol/L). After LT, 11 patients had iron evaluations; none received iron depletion therapy; all had normal transferrin saturation. The mean serum ferritin was 185 (± 99) μg/L. Magnetic resonance imaging showed that iron overload was absent in nine patients, mild in one patient with metabolic syndrome, and high (180 μmol/g) in one patient with hereditary spherocytosis discovered after LT. At the end of follow-up, serum hepcidin was normal in 10 patients (11.12 ± 7.6 nmol/L; P<0.05) and low in one patient with iron deficiency anemia. Survival was 83% and 67% at 1 and 5 years, respectively. Survival was similar for patients with HH and patients that received LT for other causes.

CONCLUSION

In HH, LT normalized hepcidin secretion and prevented recurrence of hepatic iron overload. Survival was similar to that of patients who received LTs for other liver diseases.

Monogenic diseases that can be cured by liver transplantation

While the prevalence of most diseases caused by single-gene mutations is low and defines them as rare conditions, all together, monogenic diseases account for approximately 10 in every 1000 births according to the World Health Organisation. Orthotopic liver transplantation (LT) could offer a therapeutic option in monogenic diseases in two ways: by substituting for an injured liver or by supplying a tissue that can replace a mutant protein. In this respect, LT may be regarded as the correction of a disease at the level of the dysfunctional protein. Monogenic diseases that involve the liver represent a heterogeneous group of disorders. In conditions associated with predominant liver parenchymal damage (i.e., genetic cholestatic disorders, Wilson's disease, hereditary hemochromatosis, tyrosinemia, α1 antitrypsin deficiency), hepatic complications are the major source of morbidity and LT not only replaces a dysfunctional liver but also corrects the genetic defect and effectively cures the disease. A second group includes liver-based genetic disorders characterised by an architecturally near-normal liver (urea cycle disorders, Crigler-Najjar syndrome, familial amyloid polyneuropathy, primary hyperoxaluria type 1, atypical haemolytic uremic syndrome-1). In these defects, extrahepatic complications are the main source of morbidity and mortality while liver function is relatively preserved. Combined transplantation of other organs may be required, and other surgical techniques, such as domino and auxiliary liver transplantation, have been attempted. In a third group of monogenic diseases, the underlying genetic defect is expressed at a systemic level and liver involvement is just one of the clinical manifestations. In these conditions, LT might only be partially curative since the abnormal phenotype is maintained by extrahepatic synthesis of the toxic metabolites (i.e., methylmalonic acidemia, propionic acidemia). This review focuses on principles of diagnosis, management and LT results in both paediatric and adult populations of selected liver-based monogenic diseases, which represent examples of different transplantation strategies, driven by the understanding of the expression of the underlying genetic defect.

Hepatic iron overload following liver transplantation of a C282y homozygous allograft: a case report and literature review

Hereditary haemochromatosis is a common genetic disease associated with progressive iron overload and parenchymal organ damage including liver, pancreas and heart. We report a case of inadvertent transplantation of a liver from a haemochromatosis donor to a 56-year-old Asian female. Progressive iron overload occurred over a 2 year follow up as assessed by liver biopsy and iron studies in the absence of a secondary cause of iron overload, supporting a primary role of liver rather than small intestine in the regulation of iron homeostasis in hereditary haemochromatosis.

Overview: Liver disease and transplantation

Australia has had a proud and enviable record of seminal contributions to hepatology, with many contributors. Thus, any attempt to summarize these contributions ab initio in a brief review article is a significant challenge, primarily because it is so easy to overlook or underestimate particular aspects. In this article, I have confined my comments primarily to the areas where the contributions have had a significant global impact and have clearly been recognized internationally. This means that many worthwhile Australian additions will be omitted if there was less apparent international impact. The first significant interest in liver disease in Australia was from the Melbourne group at the Walter and Eliza Hall Institute (WEHI) and Royal Melbourne Hospital, leading to seminal contributions to the description, diagnosis, aetiopathogenesis and therapy of autoimmune hepatitis and primary biliary cirrhosis. Others from Royal Prince Alfred Hospital in Sydney contributed substantially to the effects of immunosuppression of autoimmune hepatitis and to early descriptions of primary sclerosing cholangitis. Other areas where Australians have contributed significantly include steatohepatitis, iron metabolism (and in particular hemochromatosis), viral hepatitis (both at the molecular and clinical level), portal hypertension, and transplant immunology. The remarkable contribution of Professor Dame Sheila Sherlock to Australian hepatology is also summarized.

Elevated hepatic iron: a confounding factor in chronic hepatitis C

Historically, iron overload in the liver has been associated with the genetic disorders hereditary hemochromatosis and thalassemia and with unusual dietary habits. More recently, elevated hepatic iron levels also have been observed in chronic hepatitis C virus (HCV) infection. Iron overload in the liver causes many changes including induction of oxidative stress, damage to lysosomes and mitochondria, altered oxidant defense systems and stimulation of hepatocyte proliferation. Chronic HCV infection causes numerous pathogenic changes in the liver including induction of endoplasmic reticulum stress, the unfolded protein response, oxidative stress, mitochondrial dysfunction and altered growth control. Understanding the molecular and cellular changes that could occur in a liver which has elevated hepatic iron levels and in which HCV replication and gene expression are ongoing has clinical relevance and represents an area of research in need of further investigation.

Outcome of liver transplantation in hereditary hemochromatosis

Hereditary hemochromatosis (HH) is a genetic disorder of iron metabolism. It is an uncommon indication for liver transplantation (LT). It has been suggested that patients who undergo LT for cirrhosis related to HH have higher morbidity and mortality from cardiac, infectious and malignant complications. The purpose of this retrospective review was to determine whether these observations hold true in the current era. We analysed the data of 22 patients who had LT for HH from 1996 to 2007 at our center. Thirteen patients had LT for complications of end-stage liver disease, seven for hepatocellular carcinoma (HCC) and two for subacute liver failure. Cofactors promoting liver disease were identified in 15 patients. Ten patients had iron reduction with venesection before transplantation. Patient and graft survival at 1 and 5 years were 80.7%, and 74% respectively. There were seven deaths after a median follow up of 46 months either because of multiorgan failure, or caused by HCC recurrence. Bacterial infections were the commonest cause of morbidity. Patients with HH remain at a higher risk of developing HCC. Infectious complications are common. Iron reduction with preoperative venesection reduces the risk of cardiac and infection complications postoperatively. Improved survival post-LT reflects changes in selection, disease modification through venesection, and improvement in immunosuppression.

Transplantation of a liver with the C282Y mutation into a recipient heterozygous for H63D results in iron overload

Hemochromatosis is a common hereditary disease associated with progressive iron overload eventually leading to parenchymal damage of the liver, heart, pancreas, and other organs. Liver transplantation has been the single most important therapy to extend long-term survival in patients with a variety of acute and chronic liver diseases. We report a case of inadvertent transplantation of a hemochromatotic liver into a nonhemochromatotic recipient, resulting in rapid iron overload. Neither the recipient nor the donor had iron overload at the time of transplantation, but the donor liver was subsequently found to be homozygous for C282Y mutation. The report includes 8 years follow-up, serial biopsies, and molecular studies. Iron overload in our patient transplanted with a C282Y homozygous liver provides an "in vivo" model for the pathophysiology of hemochromatosis and further supports liver playing a primary role in the maintenance of iron hemostasis rather intestine being the sole regulatory site.

Is serum hepcidin causative in hemochromatosis? Novel analysis from a liver transplant with hemochromatosis

BACKGROUND

Hepcidin is a circulating hepatic hormone that regulates iron balance. It has been speculated that hepcidin insufficiency or dysregulation may be the primary defect in genetic hemochromatosis.

METHODS

A 62-year-old woman underwent elective liver transplantation for chronic hepatitis C cirrhosis. Genetic testing for hemochromatosis was subsequently performed on the donor and recipient. Liver iron concentration was measured in the donated liver at the time of transplantation, and at day 2 and day 652 post-transplant. Serum hepcidin was measured at day 935 in the recipient and in three other liver transplant recipients.

RESULTS

The donor was discovered to have significant iron overload without fibrosis, with a liver iron concentration of 326 micromol/g (normal is 0 micromol/g to 35 micromol/g). Genetic testing confirmed that the 89-year-old female donor was a typical C282Y homozygote for hemochromatosis. The recipient did not carry either the C282Y or the H63D mutation of the HFE gene for hemochromatosis. Liver biopsy was performed on the recipient on day 2 and day 652 post-transplant; the liver iron concentrations were 333 micromol/g and 253 micromol/g, respectively. Serum hepcidin in the recipient was elevated at 111 ng/mL compared with that of the three other ambulatory liver transplant recipients (66 ng/mL, 76 ng/mL and 81 ng/mL).

CONCLUSION

The liver transplant recipient described in the present report demonstrated a slight decrease in liver iron concentration over a 1.8-year follow-up period without specific therapy. Hepcidin insufficiency as a primary cause of genetic hemochromatosis seems unlikely based on the clinical profile of the present patient and the hepcidin measurements.

Function of the hemochromatosis protein HFE: Lessons from animal models

Hereditary hemochromatosis (HH) is caused by chronic hyperabsorption of dietary iron. Progressive accumulation of excess iron within tissue parenchymal cells may lead to severe organ damage. The most prevalent type of HH is linked to mutations in the HFE gene, encoding an atypical major histocompatibility complex classImolecule. Shortly after its discovery in 1996, the hemochromatosis protein HFE was shown to physically interact with transferrin receptor 1 (TfR1) and impair the uptake of transferrin-bound iron in cells. However, these findings provided no clue why HFE mutations associate with systemic iron overload. It was later established that all forms of HH result from misregulation of hepcidin expression. This liver-derived circulating peptide hormone controls iron efflux from duodenal enterocytes and reticuloendothelial macrophages by promoting the degradation of the iron exporter ferroportin. Recent studies with animal models of HH uncover a crucial role of HFE as a hepatocyte iron sensor and upstream regulator of hepcidin. Thus, hepatocyte HFE is indispensable for signaling to hepcidin, presumably as a constituent of a larger iron-sensing complex. A working model postulates that the signaling activity of HFE is silenced when the protein is bound to TfR1. An increase in the iron saturation of plasma transferrin leads to displacement of TfR1 from HFE and assembly of the putative iron-sensing complex. In this way, iron uptake by the hepatocyte is translated into upregulation of hepcidin, reinforcing the concept that the liver is the major regulatory site for systemic iron homeostasis, and not merely an iron storage depot.

Hfe acts in hepatocytes to prevent hemochromatosis

Hereditary hemochromatosis (HH) is a prevalent, potentially fatal disorder of iron metabolism hallmarked by intestinal hyperabsorption of iron, hyperferremia, and hepatic iron overload. In both humans and mice, type I HH is associated with mutations in the broadly expressed HFE/Hfe gene. To identify where Hfe acts to prevent HH, we generated mice with tissue-specific Hfe ablations. This work demonstrates that local Hfe expression in hepatocytes serves to maintain physiological iron homeostasis, answering a long-standing question in medicine and explaining earlier clinical observations.

Review article: the genetic basis of haemochromatosis

BACKGROUND

Since the seminal discovery of the HFE gene a decade ago, considerable further progress in unravelling the genetic basis of haemochromatosis has been made. Novel genes and iron overload phenotypes have been described with potential insights into the molecular pathophysiology of human iron metabolism.

AIM

To review recent key advances in the field of inherited iron overload and assess their impact on clinical practice and on our understanding of iron regulation.

METHODS

A PubMed search was undertaken predominantly using 'haemochromatosis', 'HFE', 'hepcidin' and 'ferroportin'. Illustrative cases were sought.

RESULTS

The impact of HFE mutation analysis on the management of haemochromatosis is significant and allows early accurate diagnosis. HFE is also implicated in the siderosis associated with other liver pathologies. Non-HFE genes underpinning other forms of haemochromatosis are now recognized and genotype-phenotype interactions result in a spectrum of disease. These novel gene products interact with HFE in a common pathway for iron homeostasis.

CONCLUSIONS

Further identification of non-HFE genes associated with iron homeostasis will enhance our diagnostic certainty of primary haemochromatosis and may explain the variable expression seen in HFE-related disease. Improving our understanding of the mechanisms of iron regulation may lead to novel therapeutic strategies for the management of iron overload.

Survival of liver transplant recipients with hemochromatosis in the United States

BACKGROUND AND AIMS

Earlier studies have suggested that patients with hemochromatosis have poor post-transplantation survival. We aimed to compare patients with hemochromatosis to those with other causes of liver disease with regard to post-transplantation survival.

METHODS

We compared the post-transplant survival of patients with and without hemochromatosis using data provided by the United Network for Organ Sharing on 50,306 adult, cadaveric liver transplantations performed in the United States between January 1, 1990, and July 18, 2006.

RESULTS

During 1990-1996, the post-transplantation survival of patients with hemochromatosis (n = 177) at 1 year (79.1%), 3 years (71.8%), and 5 years (64.6%) was lower than the average 1-year (86.4%), 3-year (79.5%), and 5-year (73.8%) survival of all other transplant recipients (hazard ratio for death, 1.38; 95% confidence interval [CI], 1.12-1.71). In contrast, during 1997-2006, patients with hemochromatosis (n = 217) had excellent 1-year (86.1%), 3-year (80.8%), and 5-year (77.3%) post-transplantation survival, which was not different from the 1-year (88.4%), 3-year (80.3%), and 5-year (74.0%) post-transplantation survival of all other transplant recipients (hazard ratio for death, 0.89; 95% CI, 0.65-1.22). Adjustment for donor and recipient characteristics did not substantially change these results. Compared with recipients without hemochromatosis, those with hemochromatosis were more likely to die of cardiovascular diseases and less likely to die as a result of graft failure.

CONCLUSIONS

The post-transplantation survival of patients with hemochromatosis, which was previously reported to be poor, has been excellent in the United States during the past 10 years.

[Cardiac involvement in hemochromatosis]

Cardiac involvement in hemochromatosis affects mainly the myocardium: iron overload of the myocytes reduces left ventricular distensibility. Heart failure is the most frequent manifestation of cardiac involvement. Diagnosis of cardiac involvement depends essentially on Doppler echocardiography showing abnormal left ventricular filling and, later, ventricular dilatation with left ventricular systolic dysfunction. Magnetic resonance imaging can quantify intrahepatic and intramyocardial iron levels. Age at onset of symptoms and specific organ involvement in hemochromatosis depend on the type of mutation. The two principal means of treatment by iron depletion are phlebotomy in primary hemochromatosis and excretion of iron by chemical chelation in secondary hemochromatosis. Early diagnosis and iron depletion improve survival by reducing organ iron overload, especially in the liver and the myocardium. Recent guidelines issued by Anaes (national agency for health evaluation) make it possible to identify risk factors for complications early, to determine disease stage, and to provide appropriate management as a function of disease severity.

Liver transplantation for metabolic liver diseases

Liver transplantation has become an accepted treatment for several metabolic liver diseases. With advances in organ transplantation and immunosuppressive strategies, survival rates following liver transplantation are generally excellent. When the primary metabolic defect is hepatic in origin, liver transplantation not only replaces the dysfunctional organ but also cures the underlying metabolic defect. For conditions in which the primary metabolic defect is extrahepatic, liver transplantation is usually performed for hepatic complications, although disease recurrence may occur. This article reviews common metabolic liver diseases treated with liver transplantation in the adult population.

Recurrence of nonviral diseases

As long-term graft survival and mortality after liver transplantation improve, recognition that allografts may be affected by the same disease process that resulted in the failure of the liver is of both clinical and academic importance. Recipients need to be counseled about recurrence and potential impact on graft function and graft survival; clinicians need to be aware of the potential of recurrence to interpret the clinical, laboratory, radiologic, and histologic findings and alter management. Understanding which conditions recur in the allograft and factors associated with recurrence may shed light on pathogenesis. This article discusses the recurrence of nonviral diseases after liver transplantation, diagnosis, and management.

Prognostic factors and survival in patients with hereditary hemochromatosis and cirrhosis

OBJECTIVES

The survival of treated, noncirrhotic patients with hereditary hemochromatosis is similar to that of the general population. Less is known about the outcome of cirrhotic hereditary hemochromatosis patients. The present study evaluated the survival of patients with hereditary hemochromatosis and cirrhosis.

METHODS

From an established hereditary hemochromatosis database, all cirrhotic patients diagnosed from January 1972 to August 2004 were identified. Factors associated with survival were determined using univariate and multivariate regression. Survival differences were assessed using the Kaplan-Meier life table method.

RESULTS

Ninety-five patients were identified. Sixty patients had genetic testing, 52 patients (87%) were C282Y homozygotes. Median follow-up was 9.2 years (range 0 to 30 years). Nineteen patients (20%) developed hepatocellular carcinoma, one of whom was still living following transplantation. Cumulative survival for all patients was 88% at one year, 69% at five years and 56% at 20 years. Factors associated with death on multivariate analysis included advanced Child-Pugh score and hepatocellular carcinoma. Patients with hepatocellular carcinoma were older at the time of diagnosis of cirrhosis (mean age 61 and 54.6 years, respectively; P=0.03). The mean age at the time of diagnosis of hepatocellular carcinoma was 70 years (range 48 to 79 years). No other differences were found between the groups.

CONCLUSIONS

Patients with hereditary hemochromatosis and cirrhosis are at significant risk of developing hepatocellular carcinoma. These patients are older when diagnosed with carcinoma and may have poorer survival following transplantation than patients with other causes of liver disease. Early diagnosis and treatment of hereditary hemochromatosis by preventing the development of cirrhosis may reduce the incidence of hepatocellular carcinoma in the future.

Review article: the modern diagnosis and management of haemochromatosis

Haemochromatosis is the most common genetic disease in populations of European ancestry. Despite estimates based on genetic testing in Caucasian populations of 1 in 227, many physicians consider haemochromatosis to be a rare disease. The diagnosis can be elusive because of the non-specific nature of the symptoms. Of all the symptoms, liver disease has the most consistent relationship to haemochromatosis and the prognosis of haemochromatosis is most closely linked to the degree of iron overload. With the discovery of the HFE gene in 1996, comes new insights into the pathogenesis of the disease and new diagnostic strategies. However, a growing number of new iron-related genes have been discovered and linked to other iron overload syndromes.

Revisiting hereditary hemochromatosis: current concepts and progress

Originally regarded as a rare affliction notable for its distinctive evolution to "bronze diabetes," hereditary hemochromatosis is now recognized as the most common genetic disorder in populations of European ancestry. Recent advances in our understanding of iron metabolism, the identification of the gene responsible for hemochromatosis, and large epidemiologic studies have changed the diagnostic approach toward patients with hereditary hemochromatosis and other forms of iron overload. This article reviews the pathophysiology, epidemiology, clinical features, diagnostic testing, and management of hemochromatosis for the primary care provider.

Survival after liver transplantation in patients with hepatic iron overload: the national hemochromatosis transplant registry

BACKGROUND & AIMS

Previous uncontrolled studies have suggested that patients with hepatic iron overload have a poor outcome after liver transplantation. We examined the effect of HFE mutations on posttransplantation survival in patients with hepatic iron overload.

METHODS

Two hundred sixty patients with end-stage liver disease and hepatic iron overload were enrolled from 12 liver transplantation centers. Hepatic iron concentration (HIC), hepatic iron index (HII), HFE mutation status, and survival after liver transplantation were recorded.

RESULTS

HFE-associated hemochromatosis (HH) defined as homozygosity for the C282Y (n = 14, 7.2%) mutation or compound heterozygosity for the C282Y/H63D (n = 11, 5.6%) mutation was identified in 12.8% of patients. Survival postliver transplantation was significantly lower among patients with HH (1-, 3-, and 5-year survival rates of 64%, 48%, 34%, respectively) compared with simple heterozygotes (C282Y/wt or H63D/wt) or wild-type patients. Patients with HH had a hazard ratio for death of 2.6 (P = .002) after adjustment for age, United Network for Organ Sharing status, year of transplantation, and either elevated HII or HIC. Non-HH patients with hepatic iron overload also had significantly decreased survival when compared with the overall population undergoing liver transplantation (OR = 1.4, 95% CI: 1.15-1.61, P < .001).

CONCLUSIONS

One- and 5-year survivals after liver transplantation are significantly lower among patients with HFE-associated HH. Our data also suggest that hepatic iron overload may be associated with decreased survival after liver transplantation, even in patients without HH. Early diagnosis of hepatic iron overload using HFE gene testing and iron depletion prior to liver transplantation may improve posttransplantation survival, particularly among patients with HH.

Inherited metabolic liver disease

PURPOSE OF REVIEW

The purpose of this review is to identify and discuss recent findings related to inherited metabolic disorders of the liver that increase our understanding of the pathophysiology and treatment for hemochromatosis and other iron overload disorders, Wilson disease and alpha one antitrypsin deficiency.

RECENT FINDINGS

The main theme in the recent discoveries for both iron overload disorders and Wilson disease is our increasing understanding that the phenotypic expression of these disorders are greatly influenced by genes involved in the metabolic pathways for these metals, or influence the progression of liver disease independent of metal metabolism. For example, the role of hepcidin dysregulation in hemochromatosis has been a surprising discovery that provides some mechanistic understanding for the increased iron absorption that is present in this disorder.

SUMMARY

Given the recent explosion of information on iron and copper metabolism and the cellular processing of alpha one antitrypsin, the highlights reviewed in this article will help the reader keep up to date with the current understanding of these diseases and potential future approaches to their treatment.

Hepatobiliary pathology

PURPOSE OF REVIEW

This review highlights recent publications on hepatobiliary pathology concerning several unusual types of hepatitis, fatty liver disease, disorders of the biliary tree and other topics that have a substantial impact on liver biopsy interpretation.

RECENT FINDINGS

In the outbreak of severe acute respiratory syndrome (SARS), many patients had abnormalities in liver function tests. Liver biopsy findings in three cases were reported that showed a generic picture of hepatitis, with exceptionally increased mitotic activity. The role of portal myofibroblasts in cirrhosis was examined in several studies. A newly described lesion, isolated ductular hyperplasia (IDH) was found in patients with prolonged abnormalities of liver function tests of uncertain origin. Hyperplastic, well-differentiated bile ductules were seen on liver biopsy in the absence of any identifiable biliary disease. Hereditary hemochromatosis is now a complex entity with various clinicopathological forms based on mutations in the HFE gene and other iron-homeostatic genes such as transferrin receptor 2 and ferroportin 1. In some of these heritable forms of primary iron overload, stainable iron is present in both hepatocytes and Kupffer cells. After liver transplantation, differentiating recurrent HCV infection from acute rejection on liver biopsy is problematic, with exceptionally low inter- and intra-observer reliability shown in one study.

SUMMARY

The hepatitis associated with the SARS coronavirus, Isolated Ductular Hyperplasia in patients with liver function test abnormalities and other topics with pathologic relevance are reviewed.