[Hereditary hemochromatosis: presenting manifestations and diagnostic delay]. / Hémochromatose héréditaire: circonstances de découverte et délais diagnostiques.

PURPOSE: Hereditary hemochromatosis is characterized by an excessive absorption and progressive accumulation of iron in the liver, the pancreas, the heart, and the joints. Tiredness and joint manifestations occur usually before hepatopathy, diabetes or cardiopathy. Such common and unspecific symptoms seem to be largely unknown and important diagnostic delays have been reported. The aim of this study was to investigate the discovery circumstances and the diagnostic delay. METHODS: A survey was carried out amongst French patients with C282Y homozygous hemochromatosis who were contacted through patients associations or blood centers. RESULTS: The questionnaire was answered by 374 patients. Mean age at diagnosis was 48.6±11.9years. In 53% of the cases, the serum level of ferritin was greater than 1000 µg/L. Diagnosis was based on family genetic survey (29%), or fortuitous analyses showing an abnormal serum ferritin (26%), or clinical manifestations (45%). Main complaints were joint pain, tiredness or liver disease. Only 2.1% consulted for diabetes, cardiopathy or changed complexion. Time to diagnosis was lower than 1 year for 98% of patients who presented with fatigue but from 1 to 15 years for 23.4% and 29% of patients who presented with arthropathy and hepatopathy, respectively. CONCLUSION: For 55% of patients, diagnosis was based on familial genetic survey or fortuitous abnormal results of blood samples. An initial serum level of ferritin greater than 1000 µg/L was a factor of severity for 50% of patient. These two elements must be taken into account to consider a population mass screening. Long time to diagnosis required a sensitization of the population to be aware of the clinical manifestations of hemochromatosis.

[Hereditary iron overload]. / Surcharges héréditaires en fer.

The field of hereditary iron overload has known, in the recent period, deep changes mainly related to major advances in molecular biology. It encompasses now a series of genetic entities. The mechanistic understanding of iron overload development and iron toxicity has greatly improved. The diagnostic approach has become essentially noninvasive with a major role for biological tests. From the therapeutic viewpoint, the phlebotomy treatment is now enriched by the possibility of resorting to oral chelation and by innovative perspectives directly linked to our improvement in the molecular understanding of these diseases.

[Gaucher's disease in Rennes University hospital: a 10-year retrospective study]. / Etude rétrospective sur dix ans des patients atteints de maladie de Gaucher au CHU de Rennes.

INTRODUCTION: Gaucher's disease (GD) remains rare and cohort studies are essential to improve our knowledge of this disease. METHODS: We performed a 10-year retrospective study of patients with GD followed-up in the Rennes University teaching hospital. RESULTS: Among a population of 1,500,000 inhabitants, 12 patients with GD were identified. Eight were men, and four were women. Mean age at diagnosis was 32.3 years and the first symptoms appeared around 31 years old. Main symptoms were: splenomegaly (82%), hepatomegaly (64%), thrombocytopenia (73%), anemia (64%), deterioration of general status (45%), bone pain (27%). Parkinsonism was noted in two patients, polyclonal gammopathy in two others, and monoclonal gammopathy was evidenced in four patients, with chronic lymphocytic lymphoma in one of them. Enzymatic activity dosage confirmed the diagnosis of GD for eight patients. For the remaining four patients, diagnosis was obtained by identification of Gaucher's cells on tissue examination. Substitutive enzymotherapy (SE) was performed for seven patients, with great improvement of initial symptoms. For two of these seven patients, SE is changed for miglustat with persistent improvement of clinical status. CONCLUSION: Association between GD and Parkinsonism or between GD and gammopathy was confirmed in our study. Other cohort studies are needed to improve the knowledge of GD.

[Haemochromatoses. New understanding, new treatments]. / Les hémochromatoses. Nouvelle compréhension, nouveaux traitements.

Haemochromatoses encompass a variety of genetic iron overload diseases. The most frequent entity remains HFE-related haemochromatosis. The other syndromes include diseases related to mutations of the hemojuvelin, hepcidin, transferrin receptor 2 and ferroportin genes. Iron excess is due to deficiencies in either hepcidin or ferroportin, the two key regulatory proteins of iron metabolism. Diagnosis rests essentially upon non invasive clinical, biological and imaging criteria. The mainstay of iron overload treatment is venesection therapy in case of hepcidin deficiency, the therapeutic approach for the future being hepcidin supplementation. In ferroportin deficiency, oral chelation is an interesting orientation. The recent creation in France of a reference center and of several competence centers for rare genetic iron overload diseases represents a valuable organization for improving both the understanding of the diseases and the management of the patients.

Antiproliferative and apoptotic effects in rat and human hepatoma cell cultures of the orally active iron chelator ICL670 compared to CP20: a possible relationship with polyamine metabolism.

OBJECTIVE: Iron loading has been observed to have a hyperproliferative effect on hepatocytes in vitro and on tumour cells in vivo; removal of this iron being required to induce antitumour activity. MATERIAL AND METHODS: Antiproliferative effects of orally active tridentate iron chelator ICL670 (deferasirox) and bidentate iron chelator CP20 (deferiprone), mediated through the chelation of intracellular iron, were compared in rat hepatoma cell line FAO and human hepatoma cell line HUH7. RESULTS: In FAO cell cultures, we have shown that ICL670 decreased cell viability and DNA replication and induced apoptosis more efficiently than an iron-binding equivalent concentration of CP20. Moreover, ICL670 decreased significantly the number of the cells in G(2)-M phase. In the HUH7 cell cultures, ICL670 and a four-time higher iron-binding equivalent concentration of CP20, decreased cell viability and DNA replication in the same range. CP20 increased the number of the cells in G(2)-M phase. However, ICL670 inhibited polyamine biosynthesis by decreasing ornithine decarboxylase mRNA level; in contrast, CP20 increased polyamine biosynthesis, particularly putrescine level, by stimulating spermidine-spermine N(1)-acetyl transferase activity that could activate the polyamine retro-conversion pathway. By mass spectrometry, we observed that ICL670 cellular uptake was six times higher than CP20. CONCLUSIONS: These results suggest that ICL670 has a powerful antitumoural effect and blocks cell proliferation in neoplastic cells by a pathway different from that of CP20 and may constitute a potential adjuvant drug for anticancer therapy.

Effects of phlebotomy therapy on cytochrome P450 2e1 activity and oxidative stress markers in dysmetabolic iron overload syndrome: a randomized trial.

AIM: To assess the effects of iron removal on cytochrome P450 2E1 activity and oxidative stress in dysmetabolic iron overload syndrome. METHODS: Forty-eight patients were randomized to phlebotomy therapy consisting of removal of 300-500 mL of blood every 14 days until serum ferritin levels dropped under 100 microg/L or to follow-up without phlebotomy therapy. Cytochrome P450 2E1 activity was measured at baseline and at the end of treatment by using the 6-hydroxychlorzoxazone/chlorzoxazone blood metabolic ratio, 2 h after the intake of 500 mg of chlorzoxazone. RESULTS: In the treatment group, a mean of 3.9 +/- 1.3 L of blood was removed and serum ferritin levels dropped from 715 +/- 397 to 74 +/- 34 microg/L. Variation of cytochrome P450 2E1 activity was not significantly different between the 2 groups (0.07 +/- 0.26 vs. 0.03 +/- 0.19, P = 0.36). In the treatment group, low-density lipoprotein cholesterol and vitamin E were lowered after treatment compared with control group (-0.15 +/- 0.51 vs. 0.24 +/- 0.58, P = 0.002 and -1.3 +/- 4.4 vs. 2.3 +/- 5.2, P = 0.03, respectively). Inversely, vitamin C was increased (0.5 +/- 3.5 vs. -1.8 +/- 3.9, P = 0.03). CONCLUSIONS: In dysmetabolic iron overload syndrome, reduction of iron stores does not significantly influence cytochrome P450 2E1 activity but is associated with a significant decrease of low-density lipoprotein cholesterol, suggesting that venesection therapy may be a suitable option in these patients.

[HFE hemochromatosis: pathogenic and diagnostic approach]. / Hémochromatose HFE: approche pathogénique et diagnostique.

HFE hemochromatosis is the most frequent genetic iron overload disease. It is linked to the C282Y mutation of the HFE protein, protein encoded by the HFE gene, which is located on chromosome 6. The mechanisms accounting for iron excess are not only digestive hyperabsorption of iron but also excessive recycling of macrophagic iron coming from erythrophagocytosis and secreted into the blood. Both mechanisms are linked to an HFE-related hepatic failure in producing hepcidin, a key hormone of body iron regulation. The marked phenotypic variability of C282Y homozygosity expression is likely related to both genetic and environmental factors. The HFE gene discovery has rendered non invasive the positive diagnostic of HFE hemochromatosis, which is now based first on an increased level of plasma transferrin saturation leading to the request of the HFE mutation. Then, hepatic MRI is a reliable method to quantify iron overload. The HFE gene discovery has also paved the road of an enlarged field of differential diagnoses corresponding to novel entities of non-HFE related genetic iron overload syndromes.

Genetic hemochromatosis update.

Hereditary Hemochromatosis is an autosomal recessive disease, characterized by chronic iron overload. It is mainly due to mutations of the HFE-1 gene. In the large majority of patients, the substitution of tyrosine for cysteine at amino acid 282 (C282Y) is found at the homozygous state. Since the HFE-1 hemochromatosis identification, several other entities of iron overload have been individualized. In the present article, the frequency, penetrance and pathophysiology of HFE-1 hemochromatosis as well as various clinical presentations resulting from different mutations affecting different proteins involved in iron metabolism are described.

The origin and spread of the HFE-C282Y haemochromatosis mutation.

The mutation responsible for most cases of genetic haemochromatosis in Europe (HFE C282Y) appears to have been originated as a unique event on a chromosome carrying HLA-A3 and -B7. It is often described as a "Celtic mutation"--originating in a Celtic population in central Europe and spreading west and north by population movement. It has also been suggested that Viking migrations were largely responsible for the distribution of this mutation. Two, initial estimates of the age of the mutation are compatible with either of these suggestions. Here we examine the evidence about HFE C282Y frequencies, extended haplotypes involving HLA-A and -B alleles, the validity of calculations of mutation age, selective advantage and current views on the relative importance of "demic-diffusion" (population migration) and "adoption-diffusion" (cultural change) in the neolithic transition in Europe and since then. We conclude that the HFE C282Y mutation occurred in mainland Europe before 4,000 BC.

Reinforced interferon alpha-2b and ribavirin is more effective than standard combination therapy in the retreatment of chronic hepatitis C previously nonresponsive to interferon: a randomized trial.

Interferon-alpha (IFN) monotherapy results in sustained virological clearance in a minority of patients with chronic hepatitis C. The aim of this study was to assess the effect of a reinforced regimen combining ribavirin and high-dose IFN for 48 weeks compared with a nonreinforced regimen combining a standard IFN regimen and ribavirin for 24 weeks in nonresponders with chronic hepatitis C. A total of 231 patients with chronic hepatitis C and previous nonresponse to IFN monotherapy were randomized. The reinforced group (n = 114) received IFN-2b 6 million units (MU) thrice weekly (TIW) and ribavirin for 48 weeks, and the nonreinforced group (n = 117) received IFN-2b 3 MU TIW and ribavirin for 24 weeks. The main outcome measure was a sustained virological response, defined as negative serum hepatitis C virus (HCV)-RNA 24 weeks following the end of treatment. This endpoint was determined in 98 patients of the reinforced group and 105 patients of the nonreinforced group. At the end of follow-up, a sustained virological response was observed in 29 of the 98 patients (29.6%) in the reinforced group vs 16 of the 105 patients (15.2%) in the nonreinforced group (P = 0.014). In multivariate analysis, factors associated with a sustained virological response were treated with a reinforced regimen [odds ratio (OR) 2.9; P = 0.06] and genotype 2 or 3 (OR 8.8; P < 0.0002). A total of 160 patients had paired biopsies before and after treatment. Histological activity improvement was observed in 32 of 80 patients (40%) and fibrosis worsening in 26 of 80 patients (33%) in the reinforced group vs 13 of 80 (16%) and 19 of 80 (24%) in the nonreinforced group (P = 0.30 and 0.20, respectively). Hence in nonresponders, a high-dose 48-week regimen of IFN and ribavirin combination was more effective than a regimen with interferon at lower dose and ribavirin for 24 weeks only.

Duodenal mRNA expression of iron related genes in response to iron loading and iron deficiency in four strains of mice.

BACKGROUND: Although much progress has been made recently in characterising the proteins involved in duodenal iron trafficking, regulation of intestinal iron transport remains poorly understood. It is not known whether the level of mRNA expression of these recently described molecules is genetically regulated. This is of particular interest however as genetic factors are likely to determine differences in iron status among mouse strains and probably also contribute to the phenotypic variability seen with disruption of the haemochromatosis gene. AIMS: To investigate this issue, we examined concomitant variations in duodenal cytochrome b (Dcytb), divalent metal transporter 1 (DMT1), ferroportin 1 (FPN1), hephaestin, stimulator of Fe transport (SFT), HFE, and transferrin receptor 1 (TfR1) transcripts in response to different dietary iron contents in the four mouse strains C57BL/6, DBA/2, CBA, and 129/Sv. SUBJECTS: Six mice of each strain were fed normal levels of dietary iron, six were subjected to the same diet supplemented with 2% carbonyl iron, and six were fed an iron deficient diet. METHODS: Quantification of mRNAs isolated from the duodenum was performed using real time reverse transcription-polymerase chain reaction. RESULTS: There was a significant increase in mRNA expression of Dcytb, DMT1, FPN1, and TfR1 when mice were fed an iron deficient diet, and a significant decrease in mRNA expression of these molecules when mice were fed an iron supplemented diet. Strain to strain differences were observed not only in serum transferrin saturations, with C57BL/6 mice having the lowest values, but also in hepatic iron stores and in duodenal mRNA expression of Dcytb, DMT1, FPN1, hephaestin, HFE, and TfR1. CONCLUSIONS: The results favour some degree of genetic control of mRNA levels of these molecules.

Venesection therapy of insulin resistance-associated hepatic iron overload.

BACKGROUND/AIMS: The association of hepatic iron overload with metabolic disorders has been coined as the insulin resistance-associated hepatic iron overload syndrome (IR-HIO). METHODS: Fifty-six IR-HIO patients were phlebotomized either weekly (n = 14) or bimonthly (n = 42) and compared with C282Y homozygotes and with ten IR-HIO patients treated by a low calorie diet alone. RESULTS: In venesected patients, the median amount of mobilized iron was 0.6 g in 2.8 months in females and 1.8 g in 5 months in males. Mobilized iron did not differ depending on the frequency of venesections or HFE genotype. When compared with C282Y homozygotes, IR-HIO patients had a similar amount of mobilized iron, but three-fold serum ferritin levels. The presenting symptoms (chronic fatigue and/or polyarthralgias) improved in 6/7 patients. Phlebotomies were well tolerated. In patients treated by a low calorie diet, serum ferritin levels remained stable. CONCLUSIONS: In IR-HIO patients, body iron stores are significantly increased, overestimated by serum ferritin, not modified by a low calorie diet, and safely removed by phlebotomies. Based on these data and on studies indicating that iron excess is associated with increased risk for hepatic fibrosis, cancer and cardiovascular disorders, venesection therapy can be recommended in IR-HIO patients.

Hemochromatosis at the intersection of classical medicine and molecular biology.

Hemochromatosis is a genetic disease of iron overload due to intestinal hyperabsorption of iron. It is one of the most prevalent autosomal recessive diseases in Caucasian populations. Hemochromatosis causes severe visceral and metabolic complications at adulthood, which include cirrhosis, diabetes, arthropathy and cardiac failure. A major breakthrough has been the discovery, in 1996, of the HFE gene which is strongly associated with the phenotypic expression of the disease. This discovery has, very quickly, provided a powerful genetic blood test which permits, in most cases, to establish the diagnosis in a non invasive way (i.e. without a liver biopsy). Hemochromatosis can be cured by repeated venesections provided the diagnosis has been detected sufficiently early. Moreover, an efficient preventive strategy can be applied to family members and should now be proposed to the general population. Finally, the identification of the HFE gene has paved the way for the identification of new iron overload entities.