Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0039730 (thalassemia)
 10,305 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Hemochromatosis is a syndrome which, when fully expressed, is manifested by melanoderma , diabetes mellitus, and liver cirrhosis, with iron overload involving parenchymal and reticuloendothelial cells in many organ systems. This clinical presentation may arise as a consequence of either hereditary or acquired abnormalities of iron overload, although the mechanisms are quite different. In hereditary hemochromatosis (also known as primary, or idiopathic, hemochromatosis), increased intestinal iron absorption leads to excessive accumulations of iron, throughout the body, particularly in parenchymal cells. In secondary forms of iron overload including transfusional hemosiderosis, alcoholic cirrhosis, thalassemia, sideroblastic anemia, and porphyria cutanea tarda, iron accumulates in the reticuloendothelial system initially, but with increasing amounts of total body iron, excessive iron deposits eventually accumulate in parenchymal cells throughout the body producing a picture indistinguishable from hereditary hemochromatosis. In this article, the course, prognosis, and therapy of iron overload will be reviewed in detail. Clinical and experimental data concerning the pathogenesis of the different forms of iron overload will be examined critically. In particular, information relating to possible abnormalities of reticuloendothelial function, intestinal mucosal iron transport, and alterations in serum and tissue isoferritin patterns in hereditary hemochromatosis will be analyzed, and possible directions for future research will be suggested. The mode of inheritance and linkage with the major histocompatibility (HLA) complex will be discussed. Theories on the pathogenesis of tissue damage by excess iron will be evaluated. Methods for measuring the extent of iron overload in clinical practice will be described, including measurements of serum iron, serum ferritin, iron absorption, cobalt excretion, desferrioxamine excretion, liver biopsy and tissue iron determinations, and HLA typing. Finally, unresolved problems in the understanding of the disease process, diagnosis, and therapy will be delineated.
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PMID:Iron overload disorders: natural history, pathogenesis, diagnosis, and therapy. 637 41

Some parameters of iron metabolism in 26 patients with porphyria cutanea tarda (PCT) which is often associated with mild iron overload and hepatic siderosis, are studied. Serum iron, percent transferrin saturation and ferritin were pathologically increased. Statistical comparisons were performed between PCT patients and healthy controls, liver disease patients (cirrhosis, chronic active hepatitis) and patients with associated liver siderosis (alcoholic cirrhosis, cirrhosis and chronic active hepatitis in thalassemia). Ferritin levels are higher in patients with porphyria than in healthy controls (p less than 0,001) and in patients without liver siderosis (p less than 0,001). No statistical difference is observed between patients with porphyria and patients with siderosis. A significant decrease in ferritin levels is registered after venesection therapy. The conclusion is drawn that serum ferritin increase in PCT is related to hepatic iron store amounts rather than hepatic necrosis. It is assumed that ferritin follow-up during phlebotomy therapy and also during remission is useful to indicate the exhaustion or an early replenishment of hepatic iron stores.
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PMID:[Determination of serum ferritin in porphyria cutanea tarda. A reliable sign of hepatic siderosis]. 670 23