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Query: UMLS:C0023890 (cirrhosis)
 42,195 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Iron-chelating treatment is indicated in all children on prolonged transfusion therapy (i.e., chiefly patients with thalassemia and Blackfan-Diamond anemia). The purpose of iron-chelating treatment is to prevent the development of manifestations of iron overload including cardiac hemosiderosis and insulin-dependent diabetes mellitus (which are two potentially fatal complications), hepatic cirrhosis, hypoparathyroidism, hypothyroidism, and delayed puberty. Deferoxamine is the only effective iron-chelating agent and should be given in a daily dose of 40 mg/kg at initiation of the transfusion program. Administration is by subcutaneous infusions from 8 to 10 hours per day. The goal of iron-chelating treatment is to maintain serum ferritin levels between 500 and 1,000 ng/ml. This long-term treatment is a significant burden for patients and it can be hoped that non-toxic iron-chelating agents, active by mouth, will become available.
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PMID:[Iron chelation in children]. 268 51

Idiopathic hemochromatosis is a hereditary disease characterized by a progressive iron overload secondary to high intestinal iron absorption. After a latent period of many years, manifestations of liver cirrhosis, diabetes mellitus, cardiac failure, hypogonadism, skin hyperpigmentation and arthropathy can occur. Liver cirrhosis is the most common feature and it is complicated by hepatocellular carcinoma in 30% of cases. Tests of high sensibility are available for early diagnosis. Repeated phlebotomy can prevent clinical features in asymptomatic patients and can improve prognosis in symptomatic subjects. Current concepts in idiopathic hemochromatosis are reported in this review.
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PMID:[Idiopathic hemochromatosis]. 298 52

In 67 patients (mean age 51 years, range 26-79), at diagnosis of primary haemochromatosis (PH), grade III or IV liver iron overload was present in all cases, cirrhosis in 85%, transferrin saturation greater than 80% in 75%, serum ferritin greater than 1000 micrograms/l in 84%, and overt diabetes in 48%. Alcohol intake was greater than 150 g/day in 11 patients; six were chronic hepatitis B surface antigen (HBsAg) carriers. HLA-A3 and B7 antigens were present in 64% and 23% versus respectively 22% (p less than 0.01) and 9% (p less than 0.025) in controls. Iron overload was found in the stomach, duodenum, skin and bone marrow in 57, 43, 45 and 59% of the patients studied. Sixty-three patients were followed for 1-260 months (median 24); 43 received regular iron-depleting treatment and 20 did not because of liver failure, cancer or refusal. Cumulative survival was 79%, 67% and 61% at 1, 4 and 10 years, respectively. Ten patients died from hepatocellular carcinoma and two from extrahepatic cancer. The early high mortality rate was due to some cases of advanced disease or cancer. Cumulative survival in the regularly treated group was 95% at 1 year and 91% at 4 and 10 years, which was higher than in the untreated group.
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PMID:Clinical, biochemical and histological features of primary haemochromatosis: a report of 67 cases. 302 81

Hereditary hemochromatosis is the most common cause of iron overload in adults and is probably the second most common cause of iron overload in children in the United States next to transfusional overload. Serious morbidity from this disorder of iron absorption can occur in early as well as in middle and advanced age, iron overload having been reported in children with hereditary hemochromatosis as early as 2 years of age. Younger persons differ from older persons in that the risk for iron loading in females appears to be equal to the risk for males, in contrast to a preponderance of males among older patients. Also, younger patients frequently demonstrate cardiac and gonadal involvement, with cardiac failure commonly leading to death, whereas older patients are more likely to have liver involvement and diabetes mellitus, with liver failure and hepatoma commonly leading to death. Because early diagnosis and treatment can prevent the toxicities of iron overload, appropriate screening can be lifesaving. Transferrin saturation is the most reliable screening test. Liver biopsy with objective measurement of hepatic iron stores is the most important diagnostic criterion at present, although reliable noninvasive methods for quantitating body iron are being developed. Young individuals who should be screened for iron overload include patients with cardiac myopathies, hypogonadism, amenorrhea, loss of libido, diabetes mellitus, other endocrine disorders, cirrhosis of the liver, and arthritis, as well as the siblings, parents, and children of patients with hereditary hemochromatosis or iron loading of unknown cause.
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PMID:Hereditary hemochromatosis in children, adolescents, and young adults. 305 60

Hemochromatosis is a disease in which the inappropriate absorption of iron over 30-40 yr results in tissue iron overload and the development of cirrhosis of the liver, diabetes, hypogonadism, arthropathy, and skin pigmentation. We present an infant who died at 2 days of age, and who was found to have massive iron overload in the liver. This case is consistent with a rare condition that has been called neonatal hemochromatosis. This disease is discussed in the context of an overview of iron metabolism and adult hemochromatosis.
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PMID:Neonatal hemochromatosis: a case and review of the literature. 327 60

Although alcoholic liver disease is often associated with some increase in hepatic iron stores, it is now established that when gross iron overload is present, this is due to genetic hemochromatosis. Furthermore, there appears to be a critical iron concentration necessary for the induction of hepatic fibrosis. Lipid peroxidation induced by ethanol and/or iron would appear to play a major role in hepatic damage in both humans and experimental animals. Although the exact mechanism(s) of induction of lipid peroxidation by ethanol and iron remains to be elucidated, both toxins can exert a synergistic effect upon hepatic lipid peroxidation. Iron overload has also been shown to stimulate directly hepatocyte and hepatic procollagen mRNA expression, which is further stimulated by ethanol. The observed synergism between iron and alcohol with respect to both hepatic lipid peroxidation and collagen biosynthesis offers a possible explanation of the apparent early onset of fibrosis and cirrhosis in patients with iron overload who have an excessive alcohol intake.
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PMID:Association between alcoholism and increased hepatic iron stores. 327 62

There is increasing evidence that both iron overload and iron deficiency are associated with significant abnormalities of immune function. In diseases associated with iron overload there is increased susceptibility to both infection and neoplasia. The precise mechanisms are still being unravelled but iron overload has been shown to impair antigen-specific immune responses and to reduce the number of functional helper precursor cells. Similarly, iron in vitro in concentrations reported to be present in the serum of patients with iron overload impairs the generation of cytotoxic T-cells, enhances suppressor T-cell activity and reduces the proliferative capacity of helper T-cells. The predominant tumor seen in iron overload is primary hepatocellular carcinoma; however other aetiological factors appear to be involved in addition to iron overload, especially hepatic cirrhosis. Nevertheless, primary liver cancer occurs much more frequently in hemochromatosis than in other forms of cirrhosis. Iron deficiency is associated with an altered response to infection but the relationship is again a complex one. The cellular mechanisms involved have yet to be clearly defined, although impaired T and B cell function have been demonstrated.
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PMID:Iron status and cellular immune competence. 328 53

Acquired hemosiderosis resulting from massive iron deposits in various organs, including heart, liver, and pancreas, may lead to architectural and functional disturbances of these organs. Even though iron overload can occur in nonuremic as well as in uremic individuals, the dialysis patient is at particular risk for developing hemosiderosis. Many dialysis patients receive exogenous iron from either oral iron therapy or blood transfusions. In addition, these patients seem to be at high risk for retaining iron. A diagnosis of excess iron deposition should be considered if the patient has unexplained cardiomyopathy, hepatic cirrhosis, proximal myopathy, diabetes mellitus, arthropathy, or immune dysfunction such as listeriosis. Several techniques are available for determining iron overload. Diagnostic tests include measuring serum ferritin levels, staining bone marrow preparations for excess iron, measuring tissue hemosiderin concentrations, magnetic resonance imaging, and the deferoxamine (DFO; Desferal) "challenge test." The simplest treatment for iron overload in nonuremic patients is removal of iron by venesection. However, in patients in whom venesection is not feasible, the chelating agent DFO can effectively remove excess iron. In the dialysis patient, DFO therapy can be combined with either dialysis or hemoperfusion to remove the iron-DFO complex that would otherwise be removed by the kidney. DFO therapy in the nondialyzed individual has proven to be successful, but before treatment, the benefits of the treatment must be weighed against possible adverse side effects such as cataracts, changes in color vision, and anaphylaxis. In the dialysis patient, indications for iron removal are less clearly defined.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Management of iron overload in dialysis patients. 329 89

Three sibling and two isolated-case perinates (4 newborn, 1 stillborn) died with siderotic cirrhosis and widespread parenchymal siderosis, the latter similar to that seen in both hereditary and secondary hemochromatosis. Reticuloendothelial siderosis was absent, as occurs in primary hemochromatosis. Studies of iron metabolism were performed antemortem in two of the siblings and ante-, post- and internatally in their mother, who showed hyperferremia antenatally. The only finding in the affected family suggestive of hereditary hemochromatosis was the commonly associated HLA haplotype (A3, B7) in the mother and an infant. Liver morphology, including immunocytochemistry and ultrastructure, was similar in the 5 infants and suggested that liver disease commenced as massive necrosis in midfetal life. Histologic grading and chemical assays for iron and copper on liver and spleen of the 5 index cases were compared with 26 controls; placentas were compared with 12 control placentas. Hepatic iron concentration, but not hepatic copper concentration, was significantly increased in index cases, compared with controls. Hepatic iron to copper ratio was significantly increased in index cases, compared with controls, but this ratio was unaltered in spleen and placenta. Total hepatic iron, but not total hepatic copper, was significantly increased in index cases, compared with a subgroup of 11 controls of low gestational age, similar to the fetal stage when liver disease commenced in utero. The results suggest that, irrespective of the fetal liver disease being genetic or acquired, hepatic iron overload was directly involved in pathogenesis.
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PMID:Perinatal hemochromatosis. Clinical, morphologic, and quantitative iron studies. 330 44

Rats fed chow containing finely divided elemental iron (from carbonyl-iron) develop hepatic iron overload resembling human hereditary hemochromatosis in that deposition of iron is primarily in periportal hepatocytes and with hepatic iron concentrations sufficiently high to be associated in the human disease with hepatic fibrosis or cirrhosis. In recent studies using this model, we reported changes in hepatic hemoproteins and heme oxygenase, the rate-controlling enzyme of heme breakdown. We now report effects of iron-loading on three enzymes of heme synthesis: 5-aminolevulinate synthase; the first and rate-controlling enzyme of the pathway, 5-aminolevulinate dehydrase (or porphobilinogen synthase), and uroporphyrinogen decarboxylase, the activity of which is decreased in porphyria cutanea tarda, a liver disease in which iron is known to play an important but still poorly understood role. Of the three enzymes, only activity of the dehydrase was altered by iron-loading: it was decreased significantly as early as 1 week after starting iron feeding, and with marked iron overload was 30 to 32% of control values. The degree of decrease was inversely related (r = -0.77 to -0.88) to the degree of iron overload and was partially reversed within 1 to 3 days when feeding of the iron-supplemented diet was stopped. The decrease in dehydrase activity was not attributable to lack of reduced glutathione or other disulfide-reducing agents or to zinc deficiency; nor was evidence found for inhibition by iron compounds or other possible inhibitors present in iron-loaded livers.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Hepatic heme synthesis in a new model of experimental hemochromatosis: studies in rats fed finely divided elemental iron. 367 87


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