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R Moirand

Publications and source records attributed to R Moirand.

At least 19 recordsLinked to original sources
PubMed2001

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.

Adult↗
PubMed2001

Histologic features of the liver in insulin resistance-associated iron overload. A study of 139 patients.

The aim of the present study was to describe histologic features of the liver in insulin resistance-associated hepatic iron overload (IR-HIO), defined as the association of metabolic disorders and hepatic iron overload. We included 139 patients in the study on the basis of one or more metabolic disorders and liver iron overload unrelated to usual causes. Liver biopsy specimens were reviewed, and histologic data were compared with those of a previously published, well-defined population with genetic hemochromatosis. Iron overload was characterized by a mixed pattern with iron deposits in hepatocytes and sinusoidal cells. Steatosis was present in 59.7% of patients with inflammation in 32.4% of cases. Periportal fibrosis was found in 67.4% of patients. These patients were older, had higher sinusoidal iron scores, and had a higher prevalence of steatosis and inflammation than patients without fibrosis. Iron overload in IR-HIO was histologically different from that in genetic hemochromatosis.

Adult↗
PubMed2000

[Genetics and physiopathology of hemochromatosis].

Thanks to the discovery of the HFE gene and of its mutations, it is now established that the most frequent form of hemochromatosis is related to homozygosity for the mutation C282Y, and that other types of hemochromatosis, unrelated to HFE mutations, do exist such as the juvenile hemochromatosis. From a pathophysiological standpoint, the C282Y mutation impairs HFE protein expression at the surface of the membrane and disturbs the cellular entry of iron (carried by circulating transferrin) into the cryptic duodenal cell. This, in turn, is likely to lead to an aberrant programmation of the degree of iron influx from the digestive lumen into the apical duodenal cells. The resulting hyperabsorption, which forms the basis of iron overload in hemochromatosis, is likely to implicate an overexpression of the transmembrane iron carrier DMT1. It is remarkable to observe that these major improvements in the knowledge of hemochomatosis have been accompanied by similar improvements in the understanding of normal iron metabolism.

Hemochromatosis↗
PubMed2000

[Diagnosis and treatment of genetic hemochromatosis].

Genetic hemochromatosis is an autosomal recessive disease, characterized by an increased iron absorption, leading to progressive iron overload. The fully expressed phenotype comprises fatigue, skin pigmentation, liver disease with hepatomegaly, cirrhosis and hepatocellular carcinoma, and diabetes. Arthralgias are frequent, cardiopathy or impotence may occur. This presentation is now unfrequent with earlier diagnosis, and patients are often asymptomatic--with only biochemical expression--or pauci-symptomatic (mild fatigue, arthralgias or increased transaminases). Transferrin saturation is always increased. Serum ferritin is proportional to iron burden. Diagnosis is now easy, since most patients are homozygote for the C282Y mutation of the HFE gene. Liver biopsy can be useful to quantify iron overload and assess liver fibrosis. The disease can be lethal due to liver disease, carcinoma or heart disease, but life expectancy goes to normal if patients are treated before the occurrence of cirrhosis. Treatment relies on regular venesections. Familial screening is essential.

Diagnosis, Differential↗
PubMed2000

Clinical aspects of hemochromatosis.

Hemochromatosis is one of the most frequent genetic diseases among the white populations, affecting one in three hundred persons. Its diagnosis has been radically transformed by the discovery of the HFE gene. In a given individual, the diagnosis can, from now on, be ascertained on the sole association of a plasma transferrin saturation (TS) over 45% and homozygosity for the C282Y mutation. Liver biopsy is only required to search for cirrhosis whenever there is hepatomegaly and/or serum ferritin >1000 ng/ml and/or elevated serum AST. Family screening is mandatory, primarily centered on the siblings. The treatment remains based on venesection therapy which improves many features of the disease (one of the most refractory, however, being the joint signs) and permits normal life expectancy provided the diagnosis is established prior to the development of cirrhosis or of insulin-dependent diabetes. In view of the prevalence, the non-invasive diagnosis, the spontaneous severity and the efficacy of a very simple therapy, hemochromatosis should benefit from population screening. This screening could be based, first, on the assessment of transferrin saturation, followed - when elevated - by the search for the C282Y mutation. The discovery of the HFE gene has also paved the road for the individualization of other types of iron overload syndromes which are not HFE-related.

HLA Antigens↗
PubMed2000

[Hemochromatosis].

Explore the source record for details and available documents.

Gene Expression↗
PubMed2000

[Genetic hemochromatosis and the HFE gene].

The discovery of the HFE gene has lead to considerable improvement in the understanding and the management of genetic hemochromatosis. More than 90% of well-defined patients are homozygous for the C282Y mutation, and genetic testing has become an important diagnostic tool. The significance of the other mutations in the HFE gene remain controversial: only C282Y/H63D compound heterozygotes could present with a phenotype compatible with hemochromatosis, but with a mild expression and a low penetrance. The link between iron overload and HFE mutation is explained by the interaction between HFE protein, beta-2-microglobulin and transferrin receptor, which is abolished by the C282Y mutation, but is not yet fully understood.

HLA Antigens↗
PubMed2000

[Iron overload and public health].

Genetic hemochromatosis, due to its frequency (about 300,000 cases in France) and to its severity, must be considered as a public health burden. Its curability--insofar as its diagnosis has been made early--and the disposal of non invasive and reliable phenotypic (transferrin saturation) and genotypic (HFE C282Y mutation) tests make its diagnosis easy. Thus, diagnosis faced with early clinical and biological symptoms must be promulgated as screening in probant families. General screening is still hampered by ethical and socio-economic obstacles, but should be evaluated in large prospective studies. Otherwise, the recently described insulin resistance-associated liver iron overload syndrome might account for epidemiological associations that have been reported between increased body iron stores and cancerous, cardio-vascular and hepatic disorders. This might extend markedly the impact of iron overload in public health and lead to broaden screening and prevention to all iron overload conditions.

Hemochromatosis↗
PubMed1999

Elevated parathyroid hormone 44-68 and osteoarticular changes in patients with genetic hemochromatosis.

OBJECTIVE: To determine whether the osteoarticular changes associated with genetic hemochromatosis could be explained by metabolic parathyroid hormone (PTH) disorders. METHODS: The study involved 210 patients with liver iron overload syndromes. Osteoarticular changes were numerically scored as the number of damaged joints. PTH 1-84 and 44-68 were assayed. RESULTS: An increase in serum PTH 44-68 levels was found in one-third of untreated patients who had no calcium or PTH 1-84 abnormalities. Serum PTH 44-68 levels correlated positively with serum ferritin levels. In multivariate analyses, the number of affected joints correlated positively with age, serum PTH 44-68 levels, and serum ferritin levels. CONCLUSION: Liver iron overload syndromes, especially genetic hemochromatosis, are associated with elevated circulating levels of PTH fragments containing the 44-68 region, which appears to play a role in osteoarticular changes. This increase seems to be a consequence of iron overload.

Adolescent↗
PubMed1999

Phenotypic expression of HFE mutations: a French study of 1110 unrelated iron-overloaded patients and relatives.

BACKGROUND & AIMS: Two mutations have been described in the HFE gene: C282Y and H63D. The aim of this study was to determine the phenotype of the different HFE genotypes. METHODS: Clinical symptoms and iron data were examined according to HFE genotypes in 531 unrelated patients with unexplained liver iron overload and 579 relatives of hemochromatotic patients. RESULTS: Non-C282Y +/+ patients did not markedly differ in terms of iron overload or clinical expression according to genotype, except for compound heterozygotes, who had slightly increased transferrin saturation. This contrasted with the strikingly increased expression in C282Y homozygotes. Similar phenotype/genotype correlations were observed in relatives based on serum iron test results. Family transmission of iron overload linked to HFE was exceptional in non-C282Y +/+ siblings and frequent in C282Y homozygotes. CONCLUSIONS: Iron overload in patients with the non-C282Y +/+ genotype is mild to moderate, strikingly lower than in C282Y homozygotes, and is not influenced by HFE genotype, except, to a small extent, for compound heterozygotes. The role of H63D mutation therefore seems to be marginal.

Case-Control Studies↗
PubMed1999

Insulin resistance-associated hepatic iron overload.

BACKGROUND & AIMS: Hepatic iron overload has been reported in various metabolic conditions, including the insulin-resistance syndrome (IRS) and nonalcoholic steatohepatitis (NASH). The aim of this study was to show that such hepatic iron overload is part of a unique and unrecognized entity. METHODS: A total of 161 non-C282Y-homozygous patients with unexplained hepatic iron overload were included. We determined the age; sex; presence of IRS (1 or more of the following: body mass index of >25, diabetes, or hyperlipidemia); serum iron tests and liver iron concentration (LIC; reference value, <36 micromol/g); liver function test results; C282Y and H63D HFE mutations; and liver histological status. RESULTS: Patients were predominantly male and middle-aged. Most (94%) had IRS. Transferrin saturation was increased in 35% (median, 42%; range, 13%-94%). LIC ranged from 38 to 332 micromol/g (median, 90 micromol/g), and LIC/age ratio ranged from 0.5 to 4.8 (median, 1.8). Allelic frequencies of both HFE mutations were significantly increased compared with values in normal controls (C282Y, 20% vs. 9%; H63D, 30% vs. 17%), only because of a higher prevalence of compound heterozygotes. Patients with no HFE mutations had similar degrees of iron overload as those with other genotypes, except for compound heterozygotes, who had slightly more iron burden. Steatosis was present in 25% of patients and NASH in 27%. Portal fibrosis (grades 0-3) was present in 62% of patients (grade 2 or 3 in 12%) in association with steatosis, inflammation, and increased age. Sex ratio, IRS, transferrin saturation, and LIC did not vary with liver damage. Serum ferritin concentration, liver function test results, and fibrosis grade were more elevated in patients with steatosis and NASH than in others, but LIC and allelic frequencies of HFE mutations were similar. CONCLUSIONS: This study shows that patients with unexplained hepatic iron overload are characterized by a mild to moderate iron burden and the nearly constant association of an IRS irrespective of liver damage.

Adult↗
PubMed1999

A genotypic study of 217 unrelated probands diagnosed as "genetic hemochromatosis" on "classical" phenotypic criteria.

BACKGROUND/AIMS: The HFE gene is a crucial candidate gene for hemochromatosis. The aims of this study were to assess the HFE genotypic profile in a large series of unrelated probands diagnosed as having phenotypic hemochromatosis, to characterize the sub-group of patients who were not homozygous for the major C282Y mutation, and to report the iron status of the detected HFE-identical siblings. METHODS: In 217 patients, the phenotypic diagnosis of hemochromatosis was based on strict bioclinical and/or histological criteria, and their genotypic profile (C282Y and H63D mutations) was determined. RESULTS: 1) 209 of the 217 probands were C282Y +/+. In 33 cases, an HFE-identical sibling was identified. Two of them had neither a clinical nor a biochemical phenotypic profile of hemochromatosis in the absence of any external factor which might have attenuated this expression. 2) Eight patients (seven males) were not C282Y +/+. Their genotypic profiles were: (C282Y +/-): six cases (four were H63D +/- and two H63D -/-); (C282Y -/-): two cases (one was H63D +/+, one H63D +/-). Phenotypic expression consisted of six cases of mild liver siderosis (among whom were the four compound heterozygotes and one case of alcoholic cirrhosis) and two severe cases of hepatic iron overload (one with alcoholic cirrhosis). Three HFE-identical siblings were identified, none of them presenting with iron excess. CONCLUSIONS: In our population: 1) The classical phenotypic criteria fitted, in 96.3% of cases, with a homogeneous genotypic entity defined by homozygosity for the C282Y mutation. Incomplete penetrance of the homozygous status was shown by the absence of the hemochromatosis phenotypic profile in 6% of the HFE-identical siblings. 2) A minority (3.7%) were not homozygous for C282Y. These were essentially men with mild iron overload, and might present with distinct iron overload entity(ies) as suggested by the presence in three of an HFE-identical sibling with absence of iron overload.

Adult↗
PubMed1999

Polymorphisms in the HFE gene.

Hereditary hemochromatosis is an autosomal recessive disease characterized by progressive iron overload. Recently, a candidate gene named HFE was isolated on the short arm of the chromosome 6 within which two mutations were identified: C282Y and H63D. To date, only homozygosity for the C282Y mutation is considered as a diagnostic criterion of hemochromatosis. 7.6% of the patients studied in our laboratory did not carry two copies of the C282Y mutation. On the other hand, a dysmetabolic iron overload syndrome has recently been described and the search for the C282Y and H63D mutations revealed that none of the patients was homozygous for C282Y while 67% exhibited one of the mutations. The possibility of a new mutation in the HFE gene has been raised to explain the disease in the remaining patients, as well as, in the few hemochromatotic patients without two copies of the C282Y mutation. The aim of this study was to search for new mutations in the HFE gene in 16 such patients. Direct sequencing of exons and 3 introns did not reveal any new mutation but identified a few polymorphisms.

Alleles↗