Crohn's Disease, Hemochromatosis, Hepatocellular Carcinoma, and Liver Cirrhosis: A Case Study.

Hemochromatosis, an inherited disorder characterized by excessive iron absorption and accumulation, can lead to organ damage and is a known contributor to liver cirrhosis. This case report discusses a 57-year-old man with a history of Crohn's disease, whose general practitioner identified elevated ferritin levels, cirrhotic liver features, and abnormal liver function tests. Further investigation revealed non-hereditary hemochromatosis, hepatic cirrhosis, and hepatocellular carcinoma (HCC). This case highlights the rare coexistence of hemochromatosis and Crohn's disease, underscoring the diagnostic and therapeutic challenges of managing these concurrent conditions. It also emphasizes the importance of prompt and effective treatment to prevent severe complications.

Pseudovitelliform maculopathy associated with hereditary hemochromatosis.

Background: Hereditary hemochromatosis (HH) is an inherited autosomal recessive iron metabolism disorder resulting from a C282Y mutation in the HFE gene. Mutations in the HFE gene may result in iron accumulation and oxidative stress in the retina, resulting in macular degeneration. This article describes two patients with HH who were treated with erythrocytapheresis or phlebotomy, with no exposure to deferoxamine or any other chelation therapy, and who developed visual symptoms. Case Presentation: Both patients had known diagnoses of HH. Because of visual symptoms, they were referred to the ophthalmology clinic and underwent a retinal exam, multimodal imaging, and electrodiagnostic studies, which revealed structural and functional degeneration of the central macula. Fundus photography, fluorescein angiography, and fundus autofluorescence revealed changes at the level of the retinal pigment epithelium (RPE) in the central macula. In addition, optical coherence tomography revealed subfoveal accumulation of hyperreflective material at and below the RPE. Multifocal electroretinography confirmed a decreased cone response, whereas the full-field electroretinogram was unremarkable. Genetic testing ruled out Best's vitelliform macular dystrophy and the other known hereditary macular dystrophies. The patients had known diagnoses of HH, homozygous C282Y mutations in the HFE gene, and no comorbidities; thus, we presumed that HH led to the observed morphological and functional disorders of the RPE, which in turn caused structural macular changes in both patients. Conclusions: Considering the macular findings and the nature of the patients' primary illness, we believe that the accumulation of iron and photoreceptor metabolic products caused dysfunction in the RPE, which led to morphological and functional changes in the macula. Because the patients were not treated using chelating agents, we attribute the macular changes solely to iron accumulation and oxidative stress caused by the pathophysiological processes of HH. Further studies are needed to identify the plausible molecular or cellular insults underlying pseudovitelliform macular degeneration in patients with HH.

NTBI levels in C282Y homozygotes after therapeutic phlebotomy.

C282Y homozygotes exposed to sustained elevated transferrin saturation (TS) may develop worsening clinical symptoms. This might be related to the appearance of non-transferrin bound iron (NTBI) when TS≥50% and labile plasma iron (LPI) when TS levels reach 75-80%. In this study, NTBI levels were examined in 219 randomly selected untreated and treated C282Y homozygotes. Overall, 161 of 219 had TS ≥ 50%, 124 of whom had detectable NTBI (≥0.47 µM, 1.81 µM [0.92-2.46 µM]) with a median serum ferritin 320 µg/L (226-442 µg/L). Ninety of 219 homozygotes had TS ≥ 75%, and all had detectable NTBI (2.21 µM [1.53-2.59 µM] with a median ferritin 338 µg/L [230-447 µg/L]). Of 125 homozygotes who last had phlebotomy ≥12 months ago (42 months [25-74 months], 92 had TS levels ≥ 50%, and 70 of these had NTBI ≥ 0.47 µM (2.06 µM [1.23-2.61µM]). Twenty-six of these 70 had a normal ferritin. Fifty-five of 125 had TS ≥ 75%, and NTBI was detected in all of these (2.32 µM [1.57-2.77 µM]) with a median ferritin 344 µg/L (255-418 µg/L). Eighteen of these 55 had a normal ferritin. In summary, NTBI is frequently found in C282Y homozygotes with TS ≥ 50%. Furthermore, C282Y homozygotes in the maintenance phase often have TS ≥ 50% together with a normal ferritin. Therefore, monitoring the TS level during the maintenance phase is recommended as an accessible clinical marker of the presence of NTBI.

A Mystery of Joint Pain: Is It Rheumatoid Arthritis (RA) or Hereditary Hemochromatosis (HH)?

A 58-year-old lady with a previous diagnosis of rheumatoid arthritis (RA) was referred to Rheumatology to manage her joint pains. On evaluation, it was noted that the lady did not have any signs of synovial inflammation. The patient had a negative anti-cyclic citrullinated peptide (anti-CCP) (<0.5) and negative rheumatoid factor (RF) (<10) together with high ferritin (1,507 µg/L) which led to consideration of hereditary hemochromatosis (HH) rather than RA. She was then referred to Hematology for regular venesection which settled her symptoms. This case report highlights the importance of considering HH as a differential diagnosis in patients with chronic arthritis particularly if there are no clinical signs and negative tests for RA. More retrospective studies will be needed to quantify how many cases of hemochromatosis arthropathy have been mistakenly diagnosed as RA.

Screening for hereditary haemochromatosis in patients undergoing knee arthroplasty : a retrospective cohort study of 2,035 patients.

AIMS: Hereditary haemochromatosis is a genetic disorder that is caused by several known mutations in the human homeostatic iron regulator protein (HFE) gene. Abnormal accumulation of iron causes a joint disease that resembles osteoarthritis (OA), but appears at a relatively younger age and is accompanied by cirrhosis, diabetes, and injury to other organs. Increased serum transferrin saturation and ferritin levels are known markers of haemochromatosis with high positive predictive values. METHODS: We have retrospectively analyzed the iron studies of a cohort of 2,035 patients undergoing knee joint arthroplasty due to OA. RESULTS: No patients had HFE gene C282Y, S65C, or H63D mutations testing. In total, 18 patients (2.96%) of the male cohort and 51 (3.58%) of the female cohort had pathologically increased ferritin levels that may be indicative of haemochromatosis. Seven patients (0.34%) had serum transferrin saturation above 45%. CONCLUSION: The awareness for the diagnosis of this disorder in Orthopaedics is low and needs improvement. Osteoarthritic patients undergoing knee arthroplasty should be routinely screened for haemochromatosis by iron studies and referred to genetic testing when needed. Level of evidence: Level III - Retrospective cohort study. Cite this article: Bone Jt Open 2021;2(12):1062-1066.

Correlation of genotype and phenotype in 32 patients with hereditary hemochromatosis in China.

BACKGROUND: Hereditary hemochromatosis (HH) is widely recognized and clinical manifestations of hemochromatosis-related (HFE-related) HH is well studied in European populations. Less is known about the clinical and laboratory characteristics of non-HFE related HH in Asian population. We aimed to explore the relationship between genotype and clinical phenotype in Chinese patients with non-HFE related hereditary hemochromatosis. METHODS: Peripheral blood samples and clinical data of patients with primary iron overload were collected from the China Registry of Genetic/Metabolic Liver Diseases. Sanger sequencing was performed in cases with primary iron overload, for 5 known HH related genes (HFE, HJV, HAMP, TFR2 and SLC40A1) and 2 novel iron homeostasis-related genes (DENND3 and SUGP2). The correlation of genotype and clinical phenotype in these patients was analyzed. RESULTS: Of the 32 patients with primary iron overload (23 were males and 9 were females), non-HFE variants were detected in 31 (31/32, 97%), including 8 pathogenic variants in HJV, 7 pathogenic variants in SLC40A1, 8 likely pathogenic variants in SUGP2 and 5 likely pathogenic variants in DENND3 cases. Among these 31 cases, 4 cases harbored homozygous variants, 2 cases harbored homozygous + heterozygous variants, 19 cases harbored heterozygous or combined heterozygous variants, and 6 cases harbored no any damaging variants. None of investigated cases carried damaging HAMP and TFR2 variants were found. 8 cases were classified as type 2A HH and 6 cases as type 4 HH, 10 cases as non-classical genotype, and 6 cases had no pathogenic variants from 31 cases. During the statistical analysis, we excluded one case (SLC40A1 IVS3 + 10delGTT + SUGP2 p. R639Q(homo)) with difficulty in grouping due to combined damaging variants. Cases with type 2A HH have an earlier age at diagnosis (p = 0.007). The iron index of cases in type 2A HH and type 4 HH was higher than that in other groups (p = 0.01). Arthropathy was relatively rare in all groups. None of cases with type 2A HH developed cirrhosis. Cirrhosis and diabetes are more prevalent in type 4 HH. The incidence of cirrhosis (p = 0.011), cardiac involvement (p = 0.042), diabetes (p = 0.035) and hypogonadism (p = 0.020) was statistically significant in the four groups. However, due to the limited sample size, the pairwise comparison showed no significant difference. CONCLUSIONS: This is the first comprehensive analysis about the gene variant spectrum and phenotypic aspects of non-HFE HH in China. The results will be useful to the identification, diagnosis and management of HH in China.

Clinical characteristics of endocrinopathies in Chinese patients with hereditary haemochromatosis.

AIMS: Hereditary haemochromatosis (HH) is a genetic disorder characterised by systemic iron overload and can lead to end-organ failure. However, very few data on this disorder, especially those on endocrine gland involvement in Chinese populations, are currently available. This study aimed to analyse the clinical features of endocrinopathies in patients with HH to generate concern among endocrinologists and improve the management of this disorder. MATERIALS AND METHODS: Chinese patients with HH-related endocrine dysfunction were enrolled at Peking Union Medical College Hospital from January 2010 to December 2018. All clinical data were analysed and summarised. RESULTS: A total of six patients were enrolled in this study, comprising five men and one woman; the average age was 36.5 ± 13.3 years. Mean serum ferritin concentration was 4508.8 ± 1074.3 ng/ml, and median transferrin saturation was 97.9% (96.6%-110.0%). Endocrine gland involvement associated with HH included the pancreas (5/6 patients), the adenohypophysis (5/6 patients) and the bones (1/6 patients); secondary endocrinopathies consisted of diabetes mellitus, hypogonadism, adrenal insufficiency and osteoporosis. Based on phlebotomy and iron chelation therapy, five patients were treated with exogenous insulin preparations, and three patients were treated with exogenous sex hormone replacement therapy. The clinical symptoms of five patients improved, although one patient died of hepatic encephalopathy and multiple organ failure. CONCLUSIONS: HH can cause multiple endocrinopathies. The possibility of HH should be carefully considered in patients with endocrine gland dysfunctions and concomitant elevated serum ferritin levels. Endocrine gland function should also be assessed and followed up in patients with a clear diagnosis of HH.

Physiological and pathophysiological mechanisms of hepcidin regulation: clinical implications for iron disorders.

The discovery of hepcidin has provided a solid foundation for understanding the mechanisms of systemic iron homeostasis and the aetiologies of iron disorders. Hepcidin assures the balance of circulating and stored iron levels for multiple physiological processes including oxygen transport and erythropoiesis, while limiting the toxicity of excess iron. The liver is the major site where regulatory signals from iron, erythropoietic drive and inflammation are integrated to control hepcidin production. Pathologically, hepcidin dysregulation by genetic inactivation, ineffective erythropoiesis, or inflammation leads to diseases of iron deficiency or overload such as iron-refractory iron-deficiency anaemia, anaemia of inflammation, iron-loading anaemias and hereditary haemochromatosis. In the present review, we discuss recent insights into the molecular mechanisms governing hepcidin regulation, how these pathways are disrupted in iron disorders, and how this knowledge is being used to develop novel diagnostic and therapeutic strategies.

Hereditary haemochromatosis, haemophagocytic lymphohistiocytosis and COVID-19.

BACKGROUND: Syndromes of iron overload have been shown to increase the risk of severe clinical disease in viral infections. Immune dysfunction is similarly described in hereditary haemochromatosis (HH). We present here the case of a 51-year-old man who developed severe coronavirus disease 2019 (COVID-19) complicated by suspected haemophagocytic lymphohistiocytosis (HLH). He was found to have HH post-mortem and we propose a link between his iron overload and the development of severe COVID-19. CASE REPORT: The initial clinical presentation consisted of cough, shortness of breath and fever. Pancytopenia, markedly elevated ferritin and d-dimer were present. Computed tomography (CT) showed bilateral ground glass changes consistent with COVID-19, widespread lymphadenopathy and splenomegaly. A subsequent combined nose and throat swab was positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). HLH was suspected based upon the H-score and Anakinra, an IL-1 receptor antagonist, was commenced. Liver function acutely worsened and magnetic resonance cholangiopancreatography (MRCP) revealed hepatic haemosiderosis. Intense splenic and cervical lymph node uptake were seen on a positron emission tomography (PET) scan and high doses of intravenous steroids were administered due to concerns over haematological malignancy. RESULTS: Day fourteen of admission heralded the start of progressive clinical deterioration with rapid increase in oxygen demands. Continuous positive airway pressure (CPAP) was trialled without success and the patient unfortunately died seventeen days into admission. Results returned after his death showed homozygous C282Y mutation of the HFE gene consistent with a diagnosis of HH. Post-mortem examination revealed widespread haemosiderin deposition in the liver along with lung pathology in keeping with severe COVID-19 and widespread splenic infarctions. CONCLUSION: An association between HH and COVID-19 is not currently described in the literature. What does exist, however, is an evidence base for the detrimental impacts iron overload has on viral infections in general and the negative effects of HH on the immune system. We therefore postulate that the underlying metabolic and immune disturbances seen in HH should be considered a potential risk factor for the development of severe COVID-19. This case also adds to the evidence that hyperinflammation appears to be a unique and interesting characteristic of this novel viral disease.

Osmium absorption after osmium tetroxide skin and eye exposure.

Osmium tetroxide is a strong oxidizing agent used in electron microscopy. Eye exposure may cause severe burns, and after inhalation or ingestion damage to the respiratory or gastrointestinal tract occurs. Exposure to osmium and its compounds is extremely rare. We present a case of a 32-year-old female stained by 9 mL of 2% osmium tetroxide in acetone during an accident in the laboratory, with rare dermal and ocular findings. Due to lack of data in toxicological databases and the absence of antidote, the therapy was symptomatic. Osmium was detected in serum 19 hours later (0.22 µg/L) and in urine during the 15-hour collection (three samples-7.05, 1.65 and 8.45 µg/L). In blood serum on admission, after 1 and 2 days after exposure, the levels of iron (28.2, 39.8 and 50.5 µmol/L; reference range 5.8-34.5 µmol/L) and transferrin receptor/ferritine were elevated. To our knowledge, this is the first paper documenting a significant absorption from the skin and potentially from the eye conjunctiva, based on serum and urine analysis. The relationship between increased iron in blood and exposure has not been described yet, and the mechanism remains unknown. The patient is being followed up for the unknown long-term effects.

John's story - living with hereditary haemochromatosis.

Iron can accumulate in the body due to several causes, resulting in iron overload syndrome. The most common cause is hereditary haemochromatosis (HH), a genetic disorder triggered by inactivation of the iron hormone hepcidin, which results in hyperferraemia and excessive tissue iron deposition. Other causes include repeated blood transfusion, iron-loading anaemias and some chronic liver diseases. Left undiagnosed, HH can cause significant damage to the liver, heart, pancreas and joints, because excess iron is toxic. This also increases the risk of hepatocellular carcinoma, especially in those with cirrhosis of the liver, with an estimate of 1 in 10 HH patients affected. The risk of developing type 2 diabetes is increased by 2.5-7.1 times compared with non-diabetic patients. Haemochromatosis is usually considered when elevated serum ferritin and transferrin saturation levels are found. Ferritin in excess of 300 ng/mL usually indicates iron overload. Genetic testing can identify the two most common mutations in the HFE gene - a positive result confirms the diagnosis of haemochromatosis - but there are also rare forms of the disease unrelated to HFE mutations. Liver biopsy can be used to ascertain iron accumulation and histological presence of fibrosis (cirrhosis). Assessment of the hepatic iron index is considered the gold standard for diagnosis of haemochromatosis. Magnetic resonance imaging has been used as a non-invasive alternative to accurately estimate iron deposition levels in the liver, heart, joints and pituitary gland. Population screening is not recommended; however, family members of identified people should be screened to determine their phenotypic or carrier potential. Early diagnosis enables preventative measures to be commenced. Routine treatment is by regular venesection of 500 mL of whole blood per session. An initiation phase of weekly or twice-weekly venesection is common until serum ferritin (SF) is reduced to normal. When SF and other markers are within normal range, regular venesections are usually scheduled 1-3 months apart, depending on the underlying cause and SF response. Dietary iron including red meat and fortified foods such as cereals should be avoided. Vitamin C promotes iron absorption, and supplementation should be avoided, as should alcohol, which can increase the risk of concomitant liver disease. John's story outlines a typical journey through diagnosis, treatment and care during HH while living on Arran, an island off the coast of Scotland. Subsequently, John developed hepatocellular carcinoma, and his treatment and palliative care are described. We wrote this article to give the reader an insight to this silent disorder and the value of recognising the signs and symptoms for early diagnosis and subsequent treatment.

Mild Hereditary Spherocytosis without Accompanying Hereditary Haemochromatosis: An Unrecognised Cause of Iron Overload.

Hereditary spherocytosis (HS) is a common inherited haemolytic anaemia and has great variability in its presentation. Non-transfusion iron overload in HS has only been reported with co-inheritance of hereditary haemochromatosis (HHC). We present 4 unrelated patients of East Asian ethnicity with mild HS and significant non-transfusion iron overload in the absence of known disease-causing mutations in HHC genes. We hypothesise that, in patients with mild HS, life-long chronic haemolysis and erythropoietic drive may promote iron absorption. This suggests that mild HS may not be entirely benign, and that patients with mild HS should be monitored for iron overload.

Influence of hereditary haemochromatosis on left ventricular wall thickness: does iron overload exacerbate cardiac hypertrophy?

BACKGROUND: The left ventricular (LV) hypertrophy increases the risk of heart failure. Hypertension and infiltrative cardiomyopathies are the well-known reasons of LV hypertrophy. The growing interest of scientists in this issue affects hereditary haemochromatosis (HH), which is characterised by the excess deposition of iron mostly due to HFE gene mutation. The aim of our study was to investigate the possible influence of HH on LV parameters in patients with early-diagnosed (early HH) and long-lasting and long-treated (old HH) disease. MATERIALS AND METHODS: Thirty nine early HH and 19 old HH patients were prospectively enrolled in the study; age- and sex-matched healthy volunteers constituted the appropriate control groups. All participants had echocardiography performed (including three-dimension volume and mass analysis); the iron turnover parameters were measured at the time of enrolment in every HH patients. RESULTS: Echocardiographic parameters regarding to left atrium (LA), LV thickness, mass and long axis length were significantly higher, whereas LV ejection fraction was lower in early HH in comparison to healthy persons. In old HH patients the differences were similar to those mentioned before, except LV ejection fraction. The presence of hypertension in both HH groups did not influence echo parameters, as well as diabetes in old HH. The strongest correlation in all HH group was found between the time from HH diagnosis and LA, LV thickness and volumes parameters, but the correlations between iron turnover and echo parameters were non-existent. CONCLUSIONS: Hereditary haemochromatosis, not only long-lasting, but also early-diagnosed, could lead to exacerbation of LV wall thickness and cardiac hypertrophy. This effect is not simply connected with hypertension and diabetes that are frequent additional diseases in these patients, but with the time from HH diagnosis.

Non-HFE mutations in haemochromatosis in China: combination of heterozygous mutations involving HJV signal peptide variants.

INTRODUCTION: Hereditary haemochromatosis (HH) caused by a homozygous p.C282Y mutation in haemochromatosis (HFE) gene has been well documented. However, less is known about the causative non-HFE mutation. We aimed to assess mutation patterns of haemochromatosis-related genes in Chinese patients with primary iron overload. METHODS: Patients were preanalysed for mutations in the classic HH-related genes: HFE, HJV, HAMP, TFR2 and SLC40A1. Whole exome sequencing was conducted for cases with variants in HJV signal peptide region. Representative variants were analysed for biological function. RESULTS: None of the cases analysed harboured the HFE p.C282Y; however, 21 of 22 primary iron-overload cases harboured at least one non-synonymous variant in the non-HFE genes. Specifically, p.E3D or p.Q6H variants in the HJV signal peptide region were identified in nine cases (40.9%). In two of three probands with the HJV p.E3D, exome sequencing identified accompanying variants in BMP/SMAD pathway genes, including TMPRSS6 p.T331M and BMP4 p.R269Q, and interestingly, SUGP2 p.R639Q was identified in all the three cases. Pedigree analysis showed a similar pattern of combination of heterozygous mutations in cases with HJV p.E3D or p.Q6H, with SUGP2 p.R639Q or HJV p.C321X being common mutation. In vitro siRNA interference of SUGP2 showed a novel role of downregulating the BMP/SMAD pathway. Site-directed mutagenesis of HJV p.Q6H/p.C321X in cell lines resulted in loss of membrane localisation of mutant HJV, and downregulation of p-SMAD1/5 and HAMP. CONCLUSION: Compound heterozygous mutations of HJV or combined heterozygous mutations of BMP/SMAD pathway genes, marked by HJV variants in the signal peptide region, may represent a novel aetiological factor for HH.

Hemochromatosis - modern condition of the problem.

The iron overload syndrome can be associated with various acquired states and hereditary factors. Hereditary hemochromatosis is the most common genetic disorder. Without therapeutic intervention the disease can lead to the development of life-threatening complications such as cirrhosis, hepatocellular carcinoma. The article presents data on pathogenesis, diagnosis and treatment of hereditary hemochromatosis. Own clinical observation is given.

Using iron studies to predict HFE mutations in New Zealand: implications for laboratory testing.

BACKGROUND: The diagnosis of hereditary haemochromatosis (HH) is not straightforward because symptoms are often absent or non-specific. Biochemical markers of iron-overloading may be affected by other conditions. AIM: To measure the correlation between iron studies and HFE genotype to inform evidence-based recommendations for laboratory testing in New Zealand. METHODS: Results from 2388 patients genotyped for C282Y, H63D and S65C in Wellington, New Zealand from 2007 to 2013 were compared with their biochemical phenotype as quantified by serum ferritin (SF), transferrin saturation (TS), serum iron (SI) and serum transferrin (ST). The predictive power of these markers was evaluated by receiver operator characteristic (ROC) curve analysis, and if a statistically significant association for a variable was seen, sensitivity, specificity and predictive values were calculated. RESULTS: Test ordering patterns showed that 62% of HFE genotyping tests were ordered because of an elevated SF alone and only 11% of these had a C-reactive protein test to rule out an acute phase reaction. The association between SF and significant HFE genotypes SF was low. However, TS values ≥45% predicted HH mutations with the highest sensitivity and specificity. A SF of >1000 µg/L was found in one at-risk patient (C282Y homozygote) who had a TS <45%. CONCLUSION: Our analysis highlights the need for clear guidelines for investigation of hyperferritinaemia and HH in New Zealand. Using our findings, we developed an evidence-based laboratory testing algorithm based on a TS ≥45%, a SF ≥1000 µg/L and/or a family history of HH which identified all C282Y homozygotes in this study.

How we manage patients with hereditary haemochromatosis.

A number of disorders cause iron overload: some are of genetic origin, such as hereditary haemochromatosis, while others are acquired, for instance due to repeated transfusions. This article reviews the treatment options for hereditary haemochromatosis, with special attention to the use of erythrocytapheresis. In general, therapy is based on the removal of excess body iron, for which ferritin levels are used to monitor the effectiveness of treatment. For many decades phlebotomy has been widely accepted as the standard treatment. Recent publications suggest that erythrocytapheresis, as a more individualized treatment, can provide a good balance between effectiveness, tolerability and costs. Other treatments like oral chelators and proton pomp inhibitors, which are used in selected patients, create the possibility to further individualize treatment of hereditary haemochromatosis. In the future, hepcidin-targeted therapy could provide a more fundamental approach to treatment.

Key-interventions derived from three evidence based guidelines for management and follow-up of patients with HFE haemochromatosis.

BACKGROUND: HFE-related hereditary haemochromatosis (HH) is a common autosomal recessive disorder with clinical manifestations ranging from asymptomatic disease to possible life-threatening complications. Cirrhosis, hepatocellular carcinoma, diabetes mellitus or osteoporosis can develop in HH patients not treated or monitored optimally. The purpose of this study was to develop key-interventions (KI's) to measure and improve the quality of care delivered to patients diagnosed with HH. METHODS: A RAND-Modified Delphi method was used to develop KI's. In the first round of a scoring form to prioritize the recommendations extracted from evidence-based guidelines was circulated between experts. The results of this survey were discussed in a consensus meeting, followed by a final appraisal of the selected recommendations. This resulted in a list of measurable KI's. RESULTS: Initially, 41 key recommendations on screening, diagnosis and treatment/management were extracted from three existing guidelines on HH (European Association for the Study of the Liver, American Association for the Study of Liver Diseases and Dutch guideline on HH). Finally, a core set of 24 recommendations resulted in 15 KI's. CONCLUSIONS: This manuscript presents the results of the process to develop KI's to measure and improve the quality of care for patients with HH.