Do physical exam, note ethnicity and family history. Aceruloplasminemia and atransferrinemia are further inherited disorders of iron overload caused by deficiency in ceruloplasmin or transferrin, the plasma ferroxidase. The iron disorders institute guide to hemochromatosis, 2e. Overview of iron overload msd manual consumer version. Iron is essential for life, so the body usually tightly controls iron absorption from food and recycles the iron from red blood cells. Iron overload disorder definition of iron overload disorder. Cambridge core hematology handbook of iron overload disorders by james c. Iron overload 2 free download as powerpoint presentation. Sf is also a useful guide to the risk of complications from iron overload in tm. The handbook of iron overload disorders is a compact guide to normal iron metabolism, ironrelated pathobiology, and the diagnosis and management of heritable and acquired iron overload disorders. Iron overload cardiomyopathy ioc results from the accumulation of iron in the myocardium, and it is the leading cause of death in patients. This not only impairs the function of these organs but may eventually lead to organ failure as well 1. Garrison cofounder, iron disorders institute and a team of medical advisors present a laypersons overview of a common but underdiagnosed genetic disorder of iron metabolism.
Iron overload cardiomyopathy better understanding of an. Joint world health organizationcenters for disease control and prevention technical. Iron overload can be primary, when genetically inherited as disorders of enhanced iron absorption e. Doisy department of biochemistry and molecular biology, saint louis university school of medicine, st. Iron overload toxicity is an unavoidable consequence in several diseases characterized by anemia and red blood cell transfusion requirement. Liver disease with fibrosis and eventually cirrhosis and hepatocellular. The term secondary iron overload defines a heterogeneous group of chronic conditions. Iron overload pathophysiology has benefited from significant advances in the knowledge of iron metabolism and in molecular genetics. The molecular basis of iron overload disorders and iron.
Men seem to be affected more often than women, possibly due to some combination of differences in dietary iron consumption and womens shedding of excess iron through blood loss in menstruation and childbirth. Whatever the hc type, the diagnosis rests on a noninvasive strategy, combining clinical. It is intended to guide decisions related to genetic testing and interpretation of. Excess body iron may accumulate in liver, spleen, heart, bone marrow, pituitary, pancreas and the central nervous system causing damage to these organs. Handbook of iron overload disorders by james c barton, 9780511776649, available at book depository with free delivery worldwide. In medicine, iron overload disorders are diseases caused by the accumulation of iron in the body. Iron overload disorders among hispanics san diego, california, 1995. Inherited disorders of iron overload develop as a result of disruption of systemic iron homeostasis.
But it may also develop secondary to multiple blood transfusions, which may be needed by those with types of blood cancer. From the department of pediatrics and the edward a. If left untreated, tissue iron deposition can result in organ damage. Mri for the measurement of liver iron content, and for the diagnosis and followup of iron overload disorders anita paisant, gaspard dassignies, elise bannier, edouard bardoujacquet, yves gandon pages e279e287. Iron overload usually occurs as a result of a gene mutation that causes the body to absorb more than a healthy amount of iron. Iron overload cardiomyopathy, better understanding of an. Overview of iron overload blood disorders merck manuals. Increased iron absorption, iron loading anaemias, chronic liver disease, porphyria cutanea cardia, congenital defects like atransferrinaemia, parental iron overload, african diet overload, medicinal iron overload, parental iron overload, perinatal iron overload perinatal haemochromatosis, hereditary tyrosinemia, cerebrohepatorenal syndrome, focal sequestration of iron pulmonary or renal. Patients with wild genotype or those who have single alleles of c282y and h63d or even h63d homozygous are unlikely to develop phenotypic hh. After the iron is reduced at the apical membrane, it is taken into the cell through the divalent metal transporter 1 dmt1. Morbidity is mainly due to iron accumulation in the endocrine organs especially the.
A handbook for patients many patients in the early stages of mds experience anemia, a condition characterized by a persistently low hematocrit, a measure of the bodys red. Diagnosis of the different forms of hereditary iron overload disorders. Pathophysiology and classification of iron overload. Part of this iron is highly reactive labile plasma iron, inducing free radical formation. Nhs sickle cell and thalassaemia screening programme. Nhs sickle cell and thalassaemia screening programme 3 introduction this is the fourth edition of the laboratory handbook, updating the edition published in october 2012. Other inherited iron overload disorders such as acaeruloplasminaemia, atransferrinaemia, neonatal iron overload, and autosomal dominant haemochromatosis are extremely rare conditions and account for a negligible proportion of the overall burden of inherited iron overload syndromes. A practical, clinicallyoriented handbook of iron overload disorders giving a compact guide to normal iron metabolism, iron related pathobiology, and the diagnosis and management of heritable and acquired iron overload disorders.
Diabetes mellitus and hepatic cirrhosis due to pancreas and liver damage are just two examples of diseases that. According to the iron disorders institute, you are most at risk for iron overload if. A practical, clinicallyoriented handbook of iron overload disorders giving a compact guide to normal iron metabolism, ironrelated pathobiology, and the diagnosis and management of heritable and acquired iron overload disorders. Handbook of iron overload disorders book, 2010 worldcat. Anaemia, anaemia in childhood, microcytic hypochromic anaemia, haematologic findings in iron deficiency, normocytic anaemia, haemolytic anaemia, macrocytic anaemia, clinical cases, bleeding disorders, investigating bleeding disorders in childhood, bleeding disorder clinical. Iron overload disorders involve excess accumulation of iron in body tissues as a result of hereditary and nonhereditary diseases. Handbook of iron overload disorders james c barton bok. Many of these disorders were discovered and characterized only in the last decade, and are unmentioned or inadequately described in most. Ironcatalyzed production of reactive oxygen species ros drives the pathophysiology of ironoverload disorders and hemolytic anemias, and is exacerbated when free iron is released 43.
Iron overload less often occurs as a complication of other blood disorders, chronic transfusion therapy, chronic hepatitis, or excessive iron ingestion. It is a common genetic disorder among caucasians in the united states, affecting approximately 1million people in the united states. Normal iron metabolism figure 1 dietary iron is present in two forms. Review molecular pathogenesis of iron overload d trinder, c fox, g vautier, j k olynyk gut2002. Hepcidin binds to cell surface ferroportin inducing ferroportin degradation and decreasing cellular iron export. Heme iron is taken up through mechanisms that are incompletely characterized. As transferrin becomes saturated in iron overload states, nontransferrin bound iron appears. Evaluation and treatment of secondary iron overload. As a consequence, iron overload nosology has been revisited. Haemochromatosis, also known as iron overload, is the condition where the intestines absorb too much iron from our food. A number of diagnostic tests are available, but their interpretation can be challenging.
Excess iron in vital organs, even in mild cases of iron overload, increases the risk for liver disease cirrhosis, cancer, heart attack or heart failure, diabetes mellitus, osteoarthritis, osteoporosis, metabolic syndrome, hypothyroidism, hypogonadism, numerous symptoms and in some cases premature death. Hemochromatosis or iron overload is an inherited medical condition in which there is excessive buildup of iron in the body and the body is unable to remove or excrete surplus iron. African iron overload is common in rural areas of central and southern africa. The regulation and expression of hepcidin in carcinogenesis. Iron overload is an excess storage of iron in the body. Haemochromatosis is one of the most frequent genetic disorders found in north.
This handbook is for staff working in screening laboratories. Overview of iron overload merck manuals professional edition. We hope that the information included in this manual will contribute to our. Other genetic iron overload disorders unrelated to hh. Iron is an essential element that forms an important component of metabolic and biological processes, but when present in excess, it can produce tissue damage due to oxidative stress. Following an explanation of why hemochromatosis has frequently been overlooked, they discuss the symptoms of iron overload, diagnostic tests, genetic testing. Hereditary hemochromatosis is an inherited genetic disorder in which there is excessive accumulation of iron in the body iron overload.
Hemochromatosis hc corresponds to systemic iron overload of genetic origin. Iron overload is a predictable complication in chronic transfusion therapy, but it may also occur in patients with limited or no history of transfusions zanella et al, 1993, 2001 chronic iron overload, also known as hemosiderosis, is a condition in which the body absorbs too much iron. Iron overload disorders are typically insidious, causing progressive and sometimes. A handbook for patients many patients in the early stages of mds experience anemia, a condition characterized by a persistently low hematocrit, a measure of the bodys red blood cells, or persistently low levels of hemoglobin, a blood protein that carries oxygen to the bodys tissues. Iron overload syndromes are broadly divided into two groups. People lose small amounts of iron every day, and even a healthy diet contains only a small amount of iron. Heme iron is the most easily absorbed form of iron. It describes the policies and guidance that set out the requirements for laboratories. Inherited or primary iron overload and secondary iron overload syndromes, as described in table 1 and table 2.
Dietary iron is absorbed primarily by duodenal enterocytes. Thus, people rarely have too much iron in their body. All these syndromes are characterised by iron overload. Iron overload hereditary hemochromatosis iron overload hereditary hemochromatosis posted 12204 key points elevated transferrin saturation ts, a serum iron measure, occurs in more than 2% of the population. Detection of iron deficiency in the presence of chronic infectious, inflammatory, or malignant disorders that increase plasma hepcidin is more problematic than in the absence of such disorders. Iron overload is an excess too much iron in the body. It is a common complication of pyruvate kinase deficiency for. In iron overload the serum ferritin concentration is unlikely to exceed 4 000 gl in. Iron overload occurs when iron intake is increased over a sustained period of time, either. We hypothesized that under similar states of hemolytic anemia or dysregulated iron homeostasis. Handbook of iron overload disorders ebook by james c. Organs commonly affected are the liver, heart and endocrine glands. Hemochromatosis can be a fatal disease if untreated.
Their genetic and clinical features are summarized in table 1. In such cases, the body stores the excess iron in the joints and organs like the pancreas, liver and heart. Handbook of iron overload disorders r2 digital library. Genetic disorders of iron overload of iron linked anemia can be explained by changes in the level of hepcidin or ferroportin and of the ability of ferroportin to be internalized by. Primary iron overload is caused by hemochromatosis, an inherited condition. This may arise from idiopathic hemochromatosis, excessive iron intake, chronic alcoholism, certain types of refractory anemia, or transfusional hemosiderosis. Diagnosis and treatment of hereditary hemochromatosis. Iron overload is a potentially serious problem that is often overlooked because the symptoms are nonspecific and often develop gradually.
A diet low in iron is generally recommended, but has little effect compared to venesection. Individuals affected with hereditary hemochromatosis may have no symptoms or signs and. Free radicals are responsible for the parenchymal cell injury associated with iron overload syndromes. A small proportion of these people will experience progressive iron accumulation and iron overload in body tissues. I am posting this message to find out if others have gone from iron overload to anemia. Just joining your blog now from australia recent blood test. An excessive accumulation of iron in the body due to a greater than normal absorption of iron from the gastrointestinal tract or from parenteral injection. The hematologist may be confronted to a number of iron overload syndromes, from genetic or acquired origin. Update on pathophysiology, diagnosis, and treatment massimo franchini servizio di immunoematologia e trasfusione, azienda ospedaliera di verona, italy hereditary hemochromatosis, a very common genetic defect in the caucasian population, is characterized by progressive tissue iron overload which leads to irreversible.
Treatment options such as phlebotomy, chelating agents, and erythrocytapheresis can prevent complications and target organ damage. Normal iron metabolism and the pathophysiology of iron. You have a family history of heart trouble, especially early death by heart attack or a history of diabetes, liver disease, osteoarthritis, hormone imbalances, especially hypothyroidism, or infertility. Frontiers inherited disorders of iron overload nutrition. Introduction defined as an excess of storage iron of more than 5 g, is confined to the hereditary forms of haemochromatosis, and the ironloading. This excessive buildup of iron results in severe damage of various organs, joints, and other parts of the body. Excess iron deposition in parenchymal tissue causes injury and ultimately organ dysfunction.
Iron overload may result from hereditary hemochromatosis a genetic disorder of iron metabolism or from secondary hemochromatosis, an acquired form of the disease that is due to excess oral intake or absorption of iron or to repeated blood transfusions. Emqn best practice guidelines for the molecular genetic diagnosis. The pharmacology and mechanisms of action in combining chelators is. The first section includes chapters describing the immunological and coagulationassisting functions of red blood cells and methods to measure their life span. Secondary hemochromatosis due to chronic oral iron. Once iron overload is diagnosed, the options for treatment are relatively straightforward in the majority of individuals. Many of these disorders were discovered and characterized only in. Articles most recent articles on iron overload disorder. A practical, clinicallyoriented handbook of iron overload disorders giving a compact guide to normal iron metabolism, ironrelated pathobiology, and the diagnosis and management of heritable and. People with iron overload may be advised to avoid food that are high in heme iron.
470 307 1489 266 766 956 570 1429 285 849 814 1540 896 1309 1521 65 83 747 783 816 664 1309 1439 804 1560 775 490 999 193 462 1320 1630 1346 516 716 761 241 856 592