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Individuals of sub-Saharan African descent with ferroportin Q248H are more likely to be diagnosed with African iron overload than individual without ferroportin mutation because individuals with ferroportin Q248H have elevated level of serum ferritin concentration. Individuals of African descent should also avoid drinking traditional beer.
Elevation in ferritin concentration without elevation in transferrin saturation does not rule out an iron overload disorder. This combination can be observed in loss-of-function ferroportin mutation and in aceruloplasminemia. Elevated level of ferritin concentration can be observed in acute or chronic inflammatory process without pathologic iron overload.
Ferritin level above 200 ng/mL (449 pmol/L) in women or 300 ng/mL (674 pmol/L) in men who have no signs of inflammatory disease need additional testing. Transferrin saturation above normal range in male and female also need additional testing.
Chemical evidence of tissue vitamin C deficiency and mild to moderate liver dysfunction are likely to be seen in individuals with African iron overload. Elevation in Gamma-glutamyl transpeptidase can be used as a marker for abnormalities in liver function.
The severity of iron overload can be determined and monitored using a combination of tests. Measurement of serum ferritin indicates for total body iron overload. Liver biopsy measures the iron concentration of liver. It provides the microscopic examination of the liver. Measurement of serum hepcidin levels may be useful in diagnostic for iron overload. MRI can detect the degree of magnetic disruption due to iron accumulation. MRI can measure iron accumulation within the heart, liver, and pituitary. Accumulation of iron in a single organ does not provide proper representation of the total body iron overload.
It is important to use both the imaging techniques and serum ferritin level as indicators to start the therapy of iron overload. Serum level and the imaging techniques can be used as markers for treatment progress.
First degree relatives of those with primary haemochromatosis should be screened to determine if they are a carrier or if they could develop the disease. This can allow preventive measures to be taken.
Screening the general population is not recommended.
There exist other causes of excess iron accumulation, which have to be considered before haemochromatosis is diagnosed.
- African iron overload, formerly known as Bantu siderosis, was first observed among people of African descent in Southern Africa. Originally, this was blamed on ungalvanised barrels used to store home-made beer, which led to increased oxidation and increased iron levels in the beer. Further investigation has shown that only some people drinking this sort of beer get an iron overload syndrome, and that a similar syndrome occurred in people of African descent who have had no contact with this kind of beer ("e.g.," African Americans). This led investigators to the discovery of a gene polymorphism in the gene for ferroportin which predisposes some people of African descent to iron overload.
- Transfusion haemosiderosis is the accumulation of iron, mainly in the liver, in patients who receive frequent blood transfusions (such as those with thalassaemia).
- Dyserythropoeisis, also known as myelodysplastic syndrome, is a disorder in the production of red blood cells. This leads to increased iron recycling from the bone marrow and accumulation in the liver.
There are several methods available for diagnosing and monitoring iron loading including:
- Serum ferritin: In males and postmenopausal females, a serum ferritin value of over 300 ng/mL (670 pmol/L) indicates iron overload. In premenopausal females, a serum ferritin value of over 150 or 200 ng/mL (330 or 440 pmol/L) indicates iron overload.
- Liver biopsy
- HFE
- MRI
Serum ferritin testing is a low-cost, readily available, and minimally invasive method for assessing body iron stores. However, the major problem with using it as an indicator of iron overload is that it can be elevated in a range of other medical conditions unrelated to iron levels including infection, inflammation, fever, liver disease, kidney disease, and cancer. Also, total iron binding capacity may be low, but can also be normal.
The standard of practice in diagnosis of haemochromatosis was recently reviewed by Pietrangelo. Positive HFE analysis confirms the clinical diagnosis of haemochromatosis in asymptomatic individuals with blood tests showing increased iron stores, or for predictive testing of individuals with a family history of haemochromatosis. The alleles evaluated by HFE gene analysis are evident in ~80% of patients with haemochromatosis; a negative report for HFE gene does not rule out haemochromatosis. In a patient with negative HFE gene testing, elevated iron status for no other obvious reason, and family history of liver disease, additional evaluation of liver iron concentration is indicated. In this case, diagnosis of haemochromatosis is based on biochemical analysis and histologic examination of a liver biopsy. Assessment of the hepatic iron index (HII) is considered the "gold standard" for diagnosis of haemochromatosis.
Magnetic resonance imaging (MRI) is emerging as a noninvasive alternative to accurately estimate iron deposition levels in the liver as well as heart, joints, and pituitary gland.
Based on the history, the doctor might consider specific tests to monitor organ dysfunction, such as an echocardiogram for heart failure, or blood glucose monitoring for patients with haemochromatosis diabetes.
There is no consensus on how to treat LID but one of the options is to treat it as an iron-deficiency anemia with ferrous sulfate (Iron(II) sulfate) at a dose of 100 mg x day in two doses (one at breakfast and the other at dinner) or 3 mg x Kg x day in children (also in two doses) during two or three months. The ideal would be to increase the deposits of body iron, measured as levels of ferritin in serum, trying to achieve a ferritin value between 30 and 100 ng/mL. Another clinical study has shown an increase of ferritin levels in those taking iron compared with others receiving a placebo from persons with LID. With ferritin levels higher than 100 ng/mL an increase in infections, etc. has been reported. Another way to treat LID is with an iron rich diet and in addition ascorbic acid or Vitamin C, contained in many types of fruits as oranges, kiwifruits, etc. that will increase 2 to 5-fold iron absorption.
As always, laboratory values have to be interpreted with the lab's reference values in mind and considering all aspects of the individual clinical situation.
Serum ferritin can be elevated in inflammatory conditions; so a normal serum ferritin may not always exclude iron deficiency, and the utility is improved by taking a concurrent C-reactive protein (CRP). The level of serum ferritin that is viewed as "high" depends on the condition. For example, in inflammatory bowel disease the threshold is 100, where as in chronic heart failure (CHF) the levels are 200.
There are several methods available for diagnosing and monitoring hemosiderosis including:
- Serum ferritin
- Liver biopsy
- MRI
Serum ferritin is a low cost, readily available, and minimally invasive method for assessing body iron stores. However, the major problem with using it as an indicator of hemosiderosis is that it can be elevated in a range of other medical conditions unrelated to iron levels including infection, inflammation, fever, liver disease, renal disease and cancer.
While liver biopsies provide a direct measure of liver iron concentration, the small sample size relative to the size of the liver can lead to sampling errors given the heterogeneity of iron concentration within the liver. Furthermore, the invasive nature of liver biopsy and the associated risks of complications (which can range from pain, haemorrhage, gallbladder perforation and other morbidities through to death in approx 1 in 10,000 cases) prevent it being used as a regular monitoring tool.
MRI is emerging as an alternative method for measuring liver iron loading because it is non-invasive, safer and generally cheaper to perform than liver biopsy; does not suffer from problems with sampling variability; and can be used more frequently than performing liver biopsies.
The diagnosis of atransferrinemia is done via the following means to ascertain if an individual has the condition:
- Blood test(for anemia)
- TF level
- Physical exam
- Genetic test
There are two forms of this condition that causes an absence of transferrin in the affected individual:
- Acquired atransferrinemia
- Congenital atransferrinemia
LID is present in stage 1 and 2, before anemia occurs in stage 3. These first two stages can be interpreted as depletion of iron stores and reduction of effective iron transport.
Stage 1 is characterized by loss of bone marrow iron stores while hemoglobin and serum iron levels remain normal. Serum ferritin falls to less than 20 ng/mL. Increased iron absorption, a compensatory change, results in an increased amount transferrin and consequent increased iron-binding capacity.
Stage 2 - Erythropoiesis is impaired. In spite of an increased level of transferrin, serum iron level is decreased along with transferrin saturation. Erythropoiesis impairment begins when the serum iron level falls to less than 50 μg/dL and transferrin saturation is less than 16%.
In stage 3, anemia (reduced hemoglobin levels) is present but red blood cell appearance remains normal.
Changes in the appearance of red blood cells are the hallmark of stage 4; first microcytosis and then hypochromia develop.
Iron deficiency begins to affect tissues in stage 5, manifesting as symptoms and signs.
Blood transfusion is sometimes used to treat iron deficiency with hemodynamic instability. Sometimes transfusions are considered for people who have chronic iron deficiency or who will soon go to surgery, but even if such people have low hemoglobin, they should be given oral treatment or intravenous iron.
Treatment for hemosiderin focuses on limiting the effects of the underlying disease leading to continued deposition. In hemochromatosis, this entails frequent phlebotomy granulomatosis, immune suppression is required. Limiting blood transfusions and institution of iron chelation therapy when iron overload is detected are important when managing sickle-cell anemia and other chronic hemolytic anemias.
It is unclear if screening pregnant women for iron-deficiency anemia during pregnancy improves outcomes in the United States. The same holds true for screening children who are "6 to 24 months" old.
Anemia is often discovered by routine blood tests, which generally include a complete blood count (CBC). A sufficiently low hemoglobin (Hb) by definition makes the diagnosis of anemia, and a low hematocrit value is also characteristic of anemia. Further studies will be undertaken to determine the anemia's cause. If the anemia is due to iron deficiency, one of the first abnormal values to be noted on a CBC, as the body's iron stores begin to be depleted, will be a high red blood cell distribution width (RDW), reflecting an increased variability in the size of red blood cells (RBCs).
A low mean corpuscular volume (MCV) also appears during the course of body iron depletion. It indicates a high number of abnormally small red blood cells. A low MCV, a low mean corpuscular hemoglobin or mean corpuscular hemoglobin concentration, and the corresponding appearance of RBCs on visual examination of a peripheral blood smear narrows the problem to a microcytic anemia (literally, a "small red blood cell" anemia).
The blood smear of a person with iron-deficiency anemia shows many hypochromic (pale, relatively colorless) and small RBCs, and may also show poikilocytosis (variation in shape) and anisocytosis (variation in size). With more severe iron-deficiency anemia, the peripheral blood smear may show hypochromic, pencil-shaped cells and, occasionally, small numbers of nucleated red blood cells. The platelet count may be slightly above the high limit of normal in iron-deficiency anemia (termed a mild thrombocytosis), but severe cases can present with thrombocytopenia (low platelet count).
Iron-deficiency anemia is confirmed by tests that include serum ferritin, serum iron level, serum transferrin, and total iron binding capacity (TIBC). A low serum ferritin is most commonly found. However, serum ferritin can be elevated by any type of chronic inflammation and thus is not consistently decreased in iron-deficiency anemia. Serum iron levels may be measured, but serum iron concentration is not as reliable as the measurement of both serum iron and serum iron-binding protein levels (TIBC). The ratio of serum iron to TIBC (called iron saturation or transferrin saturation index or percent) is a value with defined parameters that can help to confirm the diagnosis of iron-deficiency anemia; however, other conditions must also be considered, including other types of anemia.
Further testing may be necessary to differentiate iron-deficiency anemia from other disorders, such as thalassemia minor. It is very important not to treat people with thalassemia with an iron supplement, as this can lead to hemochromatosis. A hemoglobin electrophoresis provides useful evidence for distinguishing these two conditions, along with iron studies.
The amount of iron ingested may give a clue to potential toxicity. The therapeutic dose for iron deficiency anemia is 3–6 mg/kg/day. Toxic effects begin to occur at doses above 10–20 mg/kg of elemental iron. Ingestions of more than 50 mg/kg of elemental iron are associated with severe toxicity.
- A 325-mg tablet of ferrous sulfate heptahydrate has 65 mg (20%) of elemental iron
- A 325-mg tablet of ferrous gluconate has 39 mg (12%) of elemental iron
- A 325-mg tablet of ferrous fumarate has 107.25 mg (33%) of elemental iron
- 200 mg ferrous sulfate, dried, has 65 mg (33%) of elemental iron
In terms of blood values, iron levels above 350–500 µg/dL are considered toxic, and levels over 1000 µg/dL indicate severe iron poisoning.
While the most common symptom of PCT is the appearance of skin lesions and blistering, their appearance does not single-handedly lead to a conclusive diagnosis. Laboratory testing will commonly reveal high levels of uroporphyrinogen in the urine, clinically referred to as uroporphyrinogenuria. Additionally, testing for common risk factors such as Hepatitis C and hemochromatosis is strongly suggested, as their high prevalence in patients with PCT may require additional treatment. If clinical appearance of PCT is present, but laboratories are negative, one needs to seriously consider the diagnosis of pseudoporphyria.
Anemia of chronic disease is usually mild but can be severe. It is usually normocytic, but can be microcytic. The presence of both anemia of chronic disease and dietary iron deficiency in the same patient results in a more severe anemia.
While no single test is reliable to distinguish iron deficiency anemia from the anemia of chronic inflammation, there are sometimes some suggestive data:
- In anemia of chronic inflammation without iron deficiency, ferritin is normal or high, reflecting the fact that iron is sequestered within cells, and ferritin is being produced as an acute phase reactant. In iron deficiency anemia ferritin is low.
- Total iron-binding capacity (TIBC) is high in iron deficiency, reflecting production of more transferrin to increase iron binding; TIBC is low or normal in anemia of chronic inflammation.
Diagnosis of this disorder depends on blood tests demonstrating the absence of serum ceruloplasmin, combined with low serum copper concentration, low serum iron concentration, high serum ferritin concentration, or increased hepatic iron concentration. MRI scans can also confirm a diagnosis; abnormal low intensities can indicate iron accumulation in the brain.
All beta thalassemias may exhibit abnormal red blood cells, a family history is followed by DNA analysis. This test is used to investigate deletions and mutations in the alpha- and beta-globin-producing genes. Family studies can be done to evaluate carrier status and the types of mutations present in other family members. DNA testing is not routine, but can help diagnose thalassemia and determine carrier status. In most cases the treating physician uses a clinical prediagnosis assessing anemia symptoms: fatigue, breathlessness and poor exercise tolerance. Further genetic analysis may include HPLC should routine electrophoresis prove difficult.
Later stage treatment consists of cleaning the iron from the blood, using a chelating agent such as deferoxamine. If this fails then dialysis is the next step.
Children of affected individuals are obligate carriers for aceruloplasminemia. If the CP mutations has been identified in a related individual, prenatal testing is recommended. Siblings of those affected by the disease are at a 25% of aceruloplasminemia. In asymptomatic siblings, serum concentrations of hemoglobin and hemoglobin A1c should be monitored.
To prevent the progression of symptoms of the disease, annual glucose tolerance tests beginning in early teen years to evaluate the onset of diabetes mellitus. Those at risk should avoid taking iron supplements.
The American College of Obstetricians and Gynecologists recommends all people thinking of becoming pregnant be tested to see if they have thalassemia. Genetic counseling and genetic testing are recommended for families who carry a thalassemia trait.
A screening policy exists in Cyprus to reduce the rate of thalassemia, which, since the program's implementation in the 1970s (which also includes prenatal screening and abortion), has reduced the number of children born with the disease from one of every 158 births to almost zero.
In Iran as a premarital screening, the man's red cell indices are checked first, if he has microcytosis (mean cell hemoglobin < 27 pg or mean red cell volume < 80 fl), the woman is tested. When both are microcytic, their hemoglobin A2 concentrations are measured. If both have a concentration above 3.5% (diagnostic of thalassemia trait) they are referred to the local designated health post for genetic counseling.
Large scale awareness campaigns are being organized in India both by government and non-government organizations in favor of voluntary premarital screening to detect carriers of thalassemia and marriage between both carriers are strongly discouraged.