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Routine treatment in an otherwise-healthy person consists of regularly scheduled phlebotomies (bloodletting or erythrocytapheresis). When first diagnosed, the phlebotomies may be fairly frequent, until iron levels can be brought to within normal range. Once iron and other markers are within the normal range, treatments may be scheduled every other month or every three months depending upon the underlying cause of the iron overload and the person's iron load. A phlebotomy session typically draws between 450 to 500 cc whole blood.
For those unable to tolerate routine blood draws, there is a chelating agent available for use. The drug deferoxamine binds with iron in the bloodstream and enhances its elimination in urine and faeces. Typical treatment for chronic iron overload requires subcutaneous injection over a period of 8–12 hours daily. Two newer iron chelating drugs that are licensed for use in patients receiving regular blood transfusions to treat thalassaemia (and, thus, who develop iron overload as a result) are deferasirox and deferiprone.
It is most common in certain European populations (such as the Irish and Norwegians) and occurs in 0.6% of the population. Men with the disease are 24 times more likely to experience symptoms than affected women.
Early diagnosis is vital as the late effects of iron accumulation can be wholly prevented by periodic phlebotomies (by venesection) comparable in volume to blood donations. Initiation of treatment is recommended when ferritin levels reach 500 milligrams per litre.
Phlebotomy (or bloodletting) is usually done at a weekly interval until ferritin levels are less than 50 milligrams per litre. In order to prevent iron reaccumulation, subsequent phlebotomies are normally carried out approximately once every three to four months for males, and twice a year for females.
Standard diagnostic measures for haemochromatosis, transferrin saturation and ferritin tests, are not a part of routine medical testing. Screening for haemochromatosis is recommended if the patient has a parent, child or sibling with the disease.
Routine screening of the general population for hereditary haemochromatosis is generally not done. Mass genetic screening has been evaluated by the U.S. Preventive Services Task Force (USPSTF), among other groups. The USPSTF recommended against genetic screening of the general population for hereditary haemochromatosis because the likelihood of discovering an undiagnosed patient with clinically relevant iron overload is less than 1 in 1,000. Although there is strong evidence that treatment of iron overload can save lives in patients with transfusional iron overload, no clinical study has shown that for asymptomatic carriers of hereditary haemochromatosis treatment with venesection (phlebotomy) provides any clinical benefit. Recently, it has been suggested that patients be screened for iron overload using serum ferritin as a marker: If serum ferritin exceeds 1000 ng/mL, iron overload is very likely the cause.
Effective treatment of the disease has been confined to liver transplants. Success has also been reported with an antioxidant chelation cocktail, though its effectiveness cannot be confirmed. Based on the alloimmune cause hypothesis, a new treatment involving high-dose immunoglobulin to pregnant mothers who have had a previous pregnancy with a confirmed neonatal hemochromatosis outcome, has provided very encouraging results.
The condition is sometimes confused with juvenile hemochromatosis, which is a hereditary hemochromatosis caused by mutations of a gene called hemojuvelin. While the symptoms and outcomes for these two diseases are similar, the causes appear to be different.
Experimental gene therapy exists to treat hereditary spherocytosis in lab mice; however, this treatment has not yet been tried on humans due to all of the risks involved in human gene therapy.
Administration of cytidine monophosphate and uridine monophosphate reduces urinary orotic acid and ameliorates the anemia.
Administration of uridine, which is converted to UMP, will bypass the metabolic block and provide the body with a source of pyrimidine.
Uridine triacetate is a drug approved by FDA to be used in the treatment of hereditary orotic aciduria.
Many herbal and antioxidant remedies have been advocated for chronic liver disease but the evidence is not conclusive. Some support may be found in the orthodox medical use of two of these: N-acetyl cysteine (NAC), is the treatment of choice for acetaminophen overdose; both NAC and milk-thistle (Silybum marianum) or its derivative silibinin are used in liver poisoning from certain mushrooms, notably amanita phalloides, although the use of milk-thistle is controversial. Some common herbs are known or suspected to be harmful to the liver, including black cohosh, ma huang, chaparral, comfrey, germander, greater celandine, kava, mistletoe, pennyroyal, skull cap and valerian.
Hereditary spherocytosis is the most common disorder of the red cell membrane and affects 1 in 2,000 people of Northern European ancestry. According to Harrison's Principles of Internal Medicine, the frequency is at least 1 in 5,000.
The treatment of chronic liver disease depends on the cause. Specific conditions may be treated with medications including corticosteroids, interferon, antivirals, bile acids or other drugs. Supportive therapy for complications of cirrhosis include diuretics, albumin, vitamin K, blood products, antibiotics and nutritional therapy. Other patients may require surgery or a transplant. Transplant is required when the liver fails and there is no other alternative.
At present there is no specific treatment. Many patients with haemolytic anaemia take folic acid (vitamin B) since the greater turnover of cells consumes this vitamin. During crises transfusion may be required. Clotting problems can occur for which anticoagulation may be needed. Unlike hereditary spherocytosis, splenectomy is contraindicated.
Congenital hemolytic anemia (or hereditary hemolytic anemia) refers to hemolytic anemia which is primarily due to congenital disorders.
Hereditary persistence of fetal hemoglobin (HPFH, BrE: "Hereditary persistence of foetal haemoglobin") is a benign condition in which significant fetal hemoglobin (hemoglobin F) production continues well into adulthood, disregarding the normal shutoff point after which only adult-type hemoglobin should be produced.
The condition is usually asymptomatic, and is only noticed when screening for other hemoglobin disorders.
Treatment consists of frequent blood transfusions and chelation therapy. Potential cures include bone marrow transplantation and gene therapy.
No treatment is indicated for essential fructosuria, while the degree of fructosuria depends on the dietary fructose intake, it does not have any clinical manifestations. The amount of fructose routinely lost in urine is quite small. Other errors in fructose metabolism have greater clinical significance. Hereditary fructose intolerance, or the presence of fructose in the blood (fructosemia), is caused by a deficiency of aldolase B, the second enzyme involved in the metabolism of fructose. This enzyme deficiency results in an accumulation of fructose-1-phosphate, which inhibits the production of glucose and results in diminished regeneration of adenosine triphosphate. Clinically, patients with hereditary fructose intolerance are much more severely affected than those with essential fructosuria, with elevated uric acid, growth abnormalities and can result in coma if untreated.
Basically classified by causative mechanism, types of congenital hemolytic anemia include:
- Genetic conditions of RBC Membrane
- Hereditary spherocytosis
- Hereditary elliptocytosis
- Genetic conditions of RBC metabolism (enzyme defects). This group is sometimes called "congenital nonspherocytic (hemolytic) anemia", which is a term for a congenital hemolytic anemia without spherocytosis, and usually excluding hemoglobin abnormalities as well, but rather encompassing defects of glycolysis in the erythrocyte.
- Glucose-6-phosphate dehydrogenase deficiency (G6PD or favism)
- Pyruvate kinase deficiency
- Aldolase A deficiency
- Hemoglobinopathies/genetic conditions of hemoglobin
- Sickle cell anemia
- Congenital dyserythropoietic anemia
- Thalassemia
Those with hereditary elliptocytosis have a good prognosis, only those with very severe disease have a shortened life expectancy.
Genetic testing for the presence of mutations in protein molecules is considered to be a confirmatory testing technique. It is important to know the risks regarding the transmission and dangers of HPP.
A diagnosis of essential fructosuria is typically made after a positive test for reducing substances in the urine. The excretion of fructose in the urine is not constant, it depends largely on dietary intake.
Orotic aciduria is a disease yielding an excessive excretion of orotic acid in urine. It causes a characteristic form of anemia and may be associated with mental and physical retardation.
Orotic acid is an intermediate product in pyrimidine synthesis pathway, a subsequent product of which plays a role in conversion between dihydrofolate and tetrahydrofolate. Orotic aciduria is associated with megaloblastic anemia due to decreased pyrimidine synthesis, which leads to decreased nucleotide-lipid cofactors needed for erythrocyte membrane synthesis in the bone marrow.
The incidence of hereditary elliptocytosis is hard to determine, as many sufferers of the milder forms of the disorder are asymptomatic and their condition never comes to medical attention. Around 90% of those with this disorder are thought to fall into the asymptomatic population. It is estimated that its incidence is between 3 and 5 per 10,000 in the United States, and that those of African and Mediterranean descent are of higher risk. Because it can confer resistance to malaria, some subtypes of hereditary elliptocytosis are significantly more prevalent in regions where malaria is endemic. For example, in equatorial Africa its incidence is estimated at 60-160 per 10,000, and in Malayan natives its incidence is 1500-2000 per 10,000. Almost all forms of hereditary elliptocytosis are autosomal dominant, and both sexes are therefore at equal risk of having the condition. The most important exception to this rule of autosomal dominance is for a subtype of hereditary elliptocytosis called hereditary pyropoikilocytosis (HPP), which is autosomal recessive.
There are three major forms of hereditary elliptocytosis: common hereditary elliptocytosis, spherocytic elliptocytosis and southeast Asian ovalocytosis.
Common hereditary elliptocytosis is the most common form of elliptocytosis, and the form most extensively researched. Even when looking only at this form of elliptocytosis, there is a high degree of variability in the clinical severity of its subtypes. A clinically significant haemolytic anaemia occurs only in 5-10% of sufferers, with a strong bias towards those with more severe subtypes of the disorder.
Southeast Asian ovalocytosis and spherocytic elliptocytosis are less common subtypes predominantly affecting those of south-east Asian and European ethnic groups, respectively.
The following categorisation of the disorder demonstrates its heterogeneity:
- Common hereditary elliptocytosis (in approximate order from least severe to most severe)
- With asymptomatic carrier status - "individuals have no symptoms of disease and diagnosis is only able to be made on blood film"
- With mild disease - "individuals have no symptoms, with a mild and compensated haemolytic anaemia"
- With sporadic haemolysis - "individuals are at risk of haemolysis in the presence of particular comorbidities, including infections, and vitamin B deficiency"
- With neonatal poikilocytosis - "individuals have a symptomatic haemolytic anaemia with poikilocytosis that resolves in the first year of life"
- With chronic haemolysis - " individual has a moderate to severe symptomatic haemolytic anaemia (this subtype has variable penetrance in some pedigrees)"
- With homozygosity or compound heterozygosity - "depending on the exact mutations involved, individuals may lie anywhere in the spectrum between having a mild haemolytic anaemia and having a life-threatening haemolytic anaemia with symptoms mimicking those of HPP (see below)"
- With pyropoikilocytosis (HPP) - "individuals are typically of African descent and have a life-threateningly severe haemolytic anaemia with micropoikilocytosis (small and misshapen erythrocytes) that is compounded by a marked instability of erythrocytes in even mildly elevated temperatures (pyropoikilocytosis is often found in burns victims and is the term is commonly used in reference to such people)
- South-east Asian ovalocytosis (SAO) (also called stomatocytic elliptocytosis) - "individuals are of South-East Asian descent (typically Malaysian, Indonesian, Melanesian, New Guinean or Filipino, have a mild haemolytic anaemia, and has increased resistance to malaria"
- Spherocytic elliptocytosis (also called hereditary haemolytic ovalocytosis) - "individuals are of European descent and elliptocytes and spherocytes are simultaneously present in their blood"
Hereditary stomatocytosis describes a number of inherited autosomal dominant human conditions which affect the red blood cell, in which the membrane or outer coating of the cell 'leaks' sodium and potassium ions.
Hereditary pyropoikilocytosis (HPP) is an autosomal recessive form of hemolytic anemia characterized by an abnormal sensitivity of red blood cells to heat and erythrocyte morphology similar to that seen in thermal burns. Patients with HPP tend to experience severe haemolysis and anaemia in infancy that gradually improves, evolving toward typical elliptocytosis later in life. However, the hemolysis can lead to rapid sequestration and destruction of red cells. Splenectomy is curative when this occurs.
HPP has been associated with a defect of the erythrocyte membrane protein spectrin and with spectrin deficiency.It was characterized in 1975.It is considered a severe form of hereditary elliptocytosis.