Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019209 (hepatomegaly)
 5,798 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We studied peripheral blood erythrocyte parameters and HFE genotypes in 94 hemochromatosis probands and 132 white, normal control subjects. Mean red blood cell counts in probands and control subjects were not significantly different. However, mean values of hemoglobin, hematocrit, mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC) were significantly higher in C282Y/C282Y probands (n = 60) than in wild-type control subjects (n = 65). Probands with other HFE genotypes also had increased mean erythrocyte parameters (other than red blood cell count). Peripheral blood smears prepared before therapeutic phlebotomy revealed that erythrocytes in many probands had increased diameters and were well filled with hemoglobin. Erythrocyte parameters were similar in C282Y/C282Y probands with and without hepatomegaly, elevated serum concentrations of hepatic enzymes, hepatic cirrhosis, diabetes mellitus, arthropathy, or hypogonadism. Among C282Y/C282Y probands, significantly greater values of MCV (but not other erythrocyte parameters) occurred among those who had transferrin saturation values of 75% or greater or iron overload at diagnosis. After iron depletion, the mean MCV, MCH, and MCHC values of C282Y/C282Y probands decreased but remained significantly greater than values in wild-type control subjects. Mean values of prephlebotomy MCH and MCHC concentrations were lower in HLA-A3-positive than in HLA-A3-negative C282Y/C282Y probands. We conclude that increased values of mean hemoglobin, hematocrit, MCV, MCH, and MCHC in hemochromatosis probands are caused primarily by increased iron uptake and hemoglobin synthesis by immature erythroid cells. Mechanisms of iron uptake by erythrocytes that could explain these results are discussed.
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PMID:Peripheral blood erythrocyte parameters in hemochromatosis: evidence for increased erythrocyte hemoglobin content. 1063

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.
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PMID:[Diagnosis and treatment of genetic hemochromatosis]. 1086 97

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.
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PMID:Clinical aspects of hemochromatosis. 1109 95

Hereditary hemochromatosis is an inherited autosomal recessive disease, associated to a mutation in the recently described HFE gene, which is located on the short arm of chromosome 6. The product of this gene combines with the beta-2-microglobulin and the ferritin receptor, and regulates the iron absorption in the small intestine crypt cells. It is possible that the mutation may cause the increased iron uptake by the intestinal cells. The disease is very much common in men after the forties, and its expression is influenced by concomitant alcoholism, iron rich diet, oral and parenteral iron administration, menstrual blood loss or abnormal hemorrhages, blood donations, pregnancy, lactation, and iron malabsorption clinical conditions, like celiac disease. Many patients are asymptomatic, and the diagnosis may be suspected by hepatomegaly of unknown cause, abnormal iron metabolism tests, increased serum aminotransferase levels, diabetes mellitus, and anonymous arthropathy. Less commonly hereditary hemochromatosis presented by symptoms and signs of chronic liver disease, or by the classic triad described by Trousseau skin pigmentation, hepatomegaly and diabetes mellitus. The diagnosis is confirmed by the increased serum ferritin levels and transferrin saturation, and the stainable iron in hepatocytes, measured by scale devised by Scheuer et al, or the measurement of the hepatic iron. The C282Y mutation was found in 64 to 100% of patients; eventually, subjects with hepatic iron overload identical to hereditary hemochromatosis has no mutation, and homozygous for the C282Y mutation do not express iron overload. Iron is best and quickly removed by weekly or twice-weekly phlebotomy of 500 ml, containing approximately 250 mg iron. One to 3 years of weekly phlebotomy may be required to reduce stores to normal. As a guide to long-term maintenance therapy, is recommended phlebotomy every 3 months and the serum ferritin level should be maintained by less than 50 ng/ml.
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PMID:[Hereditary hemochromatosis]. 1217 Feb 86

Iron overload in body tissues can cause complications such as cirrhosis, cardiomyopathy, diabetes, hypogonadism and arthritis. In populations of northern European descent, most iron overload is due to hereditary haemochromatosis (HHC), a genetic condition that causes increased iron absorption. HHC can be treated or prevented by regular phlebotomy treatments. Some experts have called for population screening for HHC, so that early phlebotomy treatment can be initiated. Two screening tests are available: measurement of the serum iron transferrin saturation (Tf%) and genetic testing for HFE mutations. However, both methods have low positive predictive values. Current data suggest that most people at risk are unlikely to develop clinical symptoms and that the population prevalence of clinical complications of HHC is low, arguing against population screening. Two other prevention strategies are available. (1) Health provider education, to heighten awareness of HHC as an explanation for symptoms and signs seen in early iron overload including unexplained fatigue, joint pain, palpitations, abdominal pain, elevated liver function tests, hepatomegaly and elevated serum ferritin. (2) Family-based testing after a diagnosis of HHC, to ensure that relatives are evaluated for evidence of iron overload. More research is also needed to identify the factors that increase risk for disease in persons with excess iron uptake, to determine whether moderate iron overload is a health risk and to evaluate the causes of iron overload other than HHC.
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PMID:Hereditary haemochromatosis: a realistic approach to prevention of iron overload disease in the population. 1240 10

We report clinical and genetic characteristics of seven juvenile hemochromatosis (JH) patients (six females, one male) in two unrelated kinships from the southeastern U.S. All had severe iron overload. Mean age at diagnosis was 20 +/- 5 years (range 8-23 years). In six patients, the mean age at onset of signs and symptoms attributable to iron overload was 15 +/- 2 years (12-18 years); an 8-year-old girl had no symptoms. Six of the seven patients had hypogonadotrophic hypogonadism, two had severe cardiomyopathy, seven had hepatomegaly, two had hepatic cirrhosis, and five had hyperpigmentation. Two of four siblings with JH also had Hashimoto thyroiditis. One patient with severe cardiomyopathy improved with therapeutic phlebotomy, medical therapy for congestive heart failure, and a permanent pacemaker; the other died before phlebotomy was initiated. Estimates of average daily iron absorption before phlebotomy-induced iron depletion were 2.3, 3.1, and 1.7 mg in a male and two females, respectively. Both parents of four siblings with JH were heterozygous at two Ch1q loci (D1S1156, D1S2344); each of the four affected siblings was homozygous at both loci. An unaffected sib was heterozygous at D1S1156. One patient was heterozygous for HFE H63D, five others did not have HFE C282Y or H63D, and one was unavailable for testing. We conclude that JH occurs in the southeastern U.S. It is likely that JH allele(s) in at least one of the present kinships occur(s) on Ch1q, and presumably this represents a mutation(s) of the same gene localized to Ch1q in Italian and Greek JH kindreds. The present cases do not have HFE genotypes typical of hemochromatosis diagnosed in adults. Hashimoto thyroiditis, linked to Ch6p in many kinships, did not segregate with JH alleles on Ch1q in the present kinship.
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PMID:Juvenile hemochromatosis in the southeastern United States: a report of seven cases in two kinships. 1248 11

Hereditary hemochromatosis (HH) is the most common autosomal recessive disorder in populations of caucasian origin with a prevalence of 1 : 200-400 for homozygous patients. Currently, 4 types of HH are distinguished. The classical and most common form is type 1 hemochromatosis which is characterized by HFE gene mutations on chromosome 6. The disease results from an excessive iron absorption leading to multiple manifestations such as hepatomegaly, diabetes mellitus, cardiomyopathy, infertility, and hepatic fibrosis/cirrhosis if untreated. A distinct clinical feature of hemochromatosis is represented by involvement of the joints (arthropathy of hemochromatosis) which occurs frequently and often before iron overload is present. Severity of arthropathy usually does not correlate with the extent of iron overload. In contrast to most other manifestations, it is not improved by iron depletion but can be treated symptomatically. This review outlines clinical aspects as well as pathogenesis, diagnosis and therapy of the disease.
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PMID:[Arthropathy of hereditary hemochromatosis]. 1499 Dec 75