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Symptoms can vary from one person to another. It depends on the extent of accumulation and on the body location of the accumulation. African iron overload can be considered in patient with some of these conditions.
African iron overload, also known as (Bantu siderosis, or Dietary iron overload), is an iron overload disorder first observed among people of African descent in Southern Africa and Central Africa.
Dietary iron overload is the consumption of large amount of home-brewed beer with high amount of iron content in it. Preparing beer in iron pots or drums results in high iron content. The iron content in home-brewed beer is around 46–82 mg/l compared to 0.5 mg/l in commercial beer. Dietary overload was prevalent in both the rural and urban Black African population, with the introduction of commercial beer in urban areas, the condition has decreased. However, the condition is still common in rural areas. Until recently, studies have shown that genetics might play a role in this disorder. Combination of excess iron and functional changes in ferroportin seems to be the probable cause. This disorder can be treated with phlebotomy therapy or (iron-chelation) therapy.
Organs commonly affected by haemochromatosis are the liver, heart, and endocrine glands.
Haemochromatosis may present with the following clinical syndromes:
- Cirrhosis of the liver: Varies from zonal iron deposition to fibrosis (cirrhosis).
- Diabetes due to selective iron deposition in pancreatic islet beta cells leading to functional failure and cell death.
- Cardiomyopathy
- Arthritis, from calcium pyrophosphate deposition in joints. The most commonly affected joints are those of the hands, particularly the knuckles of the second and third fingers.
- Testicular failure
- Bronzing of the skin. This deep tan color, in concert with insulin insufficiency due to pancreatic damage, is the source of a nickname for this condition: "bronze diabetes".
- Joint pain and bone pain
The first indication of iron poisoning by ingestion is stomach pain, as iron is corrosive to the lining of the gastrointestinal tract, including the stomach. Nausea and vomiting are also common symptoms and bloody vomiting may occur. The pain then abates for 24 hours as the iron passes deeper into the body, resulting in metabolic acidosis, which in turn damages internal organs, particularly the brain and the liver. Iron poisoning can cause hypovolemic shock due to iron's potent ability to dilate the blood vessels. Death may occur from liver failure.
If intake of iron is for a prolonged period of time, symptoms are likely to be similar to other causes of iron overload.
Iron is stored in the liver, the pancreas and the heart. Long-term effects of haemochromatosis on these organs can be very serious, even fatal when untreated. For example, similar to alcoholism, haemochromatosis can cause cirrhosis of the liver. The liver is a primary storage area for iron and will naturally accumulate excess iron. Over time the liver is likely to be damaged by iron overload. Cirrhosis itself may lead to additional and more serious complications, including bleeding from dilated veins in the esophagus (esophageal varices) and stomach (gastric varices) and severe fluid retention in the abdomen (ascites). Toxins may accumulate in the blood and eventually affect mental functioning. This can lead to confusion or even coma (hepatic encephalopathy).
Liver cancer: Cirrhosis and haemochromatosis together will increase the risk of liver cancer. (Nearly one-third of people with haemochromatosis and cirrhosis eventually develop liver cancer.)
Diabetes: The pancreas which also stores iron is very important in the body’s mechanisms for sugar metabolism. Diabetes affects the way the body uses blood sugar (glucose). Diabetes is in turn the leading cause of new blindness in adults and may be involved in kidney failure and cardiovascular disease.
Congestive heart failure: If excess iron in the heart interferes with the its ability to circulate enough blood, a number of problems can occur, even death. The condition may be reversible when haemochromatosis is treated and excess iron stores reduced.
Heart arrhythmias: Arrhythmia or abnormal heart rhythms can cause heart palpitations, chest pain and light-headedness and are occasionally life-threatening. This condition can often be reversed with treatment for haemochromatosis.
Pigment changes: Bronze or grey coloration of the skin is caused primarily by increased melanin deposition, with iron deposition playing a lesser role.
Symptoms of iron deficiency can occur even before the condition has progressed to iron deficiency anemia.
Symptoms of iron deficiency are not unique to iron deficiency (i.e. not pathognomonic). Iron is needed for many enzymes to function normally, so a wide range of symptoms may eventually emerge, either as the secondary result of the anemia, or as other primary results of iron deficiency. Symptoms of iron deficiency include:
- fatigue
- dizziness/lightheadedness
- pallor
- hair loss
- twitches
- irritability
- weakness
- pica
- brittle or grooved nails
- hair thinning
- Plummer–Vinson syndrome: painful atrophy of the mucous membrane covering the tongue, the pharynx and the esophagus
- impaired immune function
- pagophagia
- restless legs syndrome
Continued iron deficiency may progress to anaemia and worsening fatigue. Thrombocytosis, or an elevated platelet count, can also result. A lack of sufficient iron levels in the blood is a reason that some people cannot donate blood.
Iron overload, also known as haemochromatosis, indicates accumulation of iron in the body from any cause. The most important causes are hereditary haemochromatosis (HHC), a genetic disorder, and transfusional iron overload, which can result from repeated blood transfusions.
Haemochromatosis is in its manifestations, "i.e.", often presenting with signs or symptoms suggestive of other diagnoses that affect specific organ systems. Many of the signs and symptoms below are uncommon and most patients with the hereditary form of haemochromatosis do not show any overt signs of disease nor do they suffer premature morbidity.
The classic triad of cirrhosis, bronze skin and diabetes is not as common any more because of earlier diagnosis.
The more common clinical manifestations include:
- Fatigue
- Malaise
- Joint and bone pain
- Liver cirrhosis (with an increased risk of hepatocellular carcinoma) Liver disease is always preceded by evidence of liver dysfunction including elevated serum enzymes specific to the liver, clubbing of the fingers, leuconychia, asterixis, hepatomegaly, palmar erythema and spider naevi. Cirrhosis can also present with jaundice (yellowing of the skin) and ascites.
- Insulin resistance (often patients have already been diagnosed with diabetes mellitus type 2) due to pancreatic damage from iron deposition
- Erectile dysfunction and hypogonadism, resulting in decreased libido
- Congestive heart failure, abnormal heart rhythms or pericarditis
- Arthritis of the hands (especially the second and third MCP joints), but also the knee and shoulder joints
- Damage to the adrenal gland, leading to adrenal insufficiency
Less common findings including:
- Deafness
- Dyskinesias, including Parkinsonian symptoms
- Dysfunction of certain endocrine organs:
- Parathyroid gland (leading to hypocalcaemia)
- Pituitary gland
- More commonly a slate-grey or less commonly darkish colour to the skin (see pigmentation, hence its name "diabetes bronze" when it was first described by Armand Trousseau in 1865)
- An increased susceptibility to certain infectious diseases caused by siderophilic microorganisms:
- "Vibrio vulnificus" infections from eating seafood or wound infection
- "Listeria monocytogenes"
- "Yersinia enterocolica"
- "Salmonella enterica" (serotype Typhymurium)
- "Klebsiella pneumoniae"
- "Escherichia coli"
- "Rhizopus arrhizus"
- "Mucor" species
Males are usually diagnosed after their forties and fifties, and women several decades later, owing to regular iron loss through menstruation (which ceases in menopause). The severity of clinical disease in the hereditary form varies considerably. There is evidence suggesting that hereditary haemochromatosis patients affected with other liver ailments such as hepatitis or alcoholic liver disease suffer worse liver disease than those with either condition alone. There are also juvenile forms of hereditary haemochromatosis that present in childhood with the same consequences of iron overload.
Iron poisoning is an iron overload caused by a large excess of iron intake and usually refers to an acute overload rather than a gradual one. The term has been primarily associated with young children who consumed large quantities of iron supplement pills, which resemble sweets and are widely used, including by pregnant women; approximately 3 grams is lethal for a two-year-old. Targeted packaging restrictions in the US for supplement containers with over 250 mg elemental iron have existed since 1978, and recommendations for unit packaging have reduced the several iron poisoning fatalities per year to almost zero since 1998. No known cases of iron poisoning have been identified that are associated with iron mining.
The presentation of this disorder entails anemia, arthritis, hepatic anomalies, and recurrent infections are clinical signs of the disease. Iron overload occurs mainly in the liver, heart, pancreas, thyroid, and kidney
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.
Latent iron deficiency (LID), also called iron-deficient erythropoiesis, is a medical condition in which there is evidence of iron deficiency without anemia (normal hemoglobin level). It is important to assess this condition because it is accepted that individuals with latent iron deficiency will develop iron-deficiency anemia in the weeks or months following diagnoses of LID if they are not treated with iron supplementation. In addition, there is some evidence of a decrease in vitality and an increase in fatigue among individuals that have LID.
The clinical features of LID are in discussion, some studies have not shown a clear difference between individuals with LID and control a group of the same age, gender and origin without LID. But may be it is not wrong to say that the persons with LID have a mild decrease in vitality and increase of fatigue. What seems important for preventive healthcare is to detect this medical condition, because it will avoid the patient probably developing an iron-deficiency anemia.
Atransferrinemia, also called familial hypotransferrinemia, is an autosomal recessive metabolic disorder in which there is an absence of transferrin, a plasma protein that transports iron through the blood.
Atransferrinemia is characterized by anemia and hemosiderosis in the heart and liver. The iron damage to the heart can lead to heart failure. The anemia is typically microcytic and hypochromic (the red blood cells are abnormally small and pale). Atransferrinemia was first described in 1961 and is extremely rare, with only ten documented cases worldwide.
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.
Hemosiderosis (AmE) or haemosiderosis (BrE) is a form of iron overload disorder resulting in the accumulation of hemosiderin.
Types include:
- Transfusion hemosiderosis
- Idiopathic pulmonary hemosiderosis
- Transfusional diabetes
Hemosiderin deposition in the lungs is often seen after diffuse alveolar hemorrhage, which occurs in diseases such as Goodpasture's syndrome, granulomatosis with polyangiitis, and idiopathic pulmonary hemosiderosis. Mitral stenosis can also lead to pulmonary hemosiderosis. Hemosiderin collects throughout the body in hemochromatosis. Hemosiderin deposition in the liver is a common feature of hemochromatosis and is the cause of liver failure in the disease. Selective iron deposition in the beta cells of pancreatic islets leads to diabetes due to distribution of transferrin receptor on the beta cells of islets and in the skin leads to hyperpigmentation. Hemosiderin deposition in the brain is seen after bleeds from any source, including chronic subdural hemorrhage, cerebral arteriovenous malformations, cavernous hemangiomata. Hemosiderin collects in the skin and is slowly removed after bruising; hemosiderin may remain in some conditions such as stasis dermatitis. Hemosiderin in the kidneys has been associated with marked hemolysis and a rare blood disorder called paroxysmal nocturnal hemoglobinuria.
Hemosiderin may deposit in diseases associated with iron overload. These diseases are typically diseases in which chronic blood loss requires frequent blood transfusions, such as sickle cell anemia and thalassemia, though beta thalassemia minor has been associated with hemosiderin deposits in the liver in those with non-alcoholic fatty liver disease independent of any transfusions.
Siderosis is the deposition of iron in tissue.
When used without qualification, it usually refers to an environmental disease of the lung.
Also Siderosis Bulbi, deposition of iron into the eye causing injury as the material chemically reacts with tissues and cells.
Genes involved in iron metabolism disorders include HFE and TFR2.
Hepcidin is the master regulator of iron metabolism and, therefore, most genetic forms of iron overload can be thought of as relative hepcidin deficiency in one way or another. For instance, a severe form of iron overload, juvenile hemochromatosis, is a result of severe hepcidin deficiency. The majority of cases are caused by mutations in the hemojuvelin gene (HJV or RGMc/repulsive guidance molecule c). The exceptions, people who have mutations in the gene for ferroportin, prove the rule: these people have plenty of hepcidin, but their cells lack the proper response to it. So, in people with ferroportin proteins that transport iron out of cells without responding to hepcidin's signals to stop, they have a deficiency in the action of hepcidin, if not in hepcidin itself.
But the exact mechanisms of most of the various forms of adult hemochromatosis, which make up most of the genetic iron overload disorders, remain unsolved. So while researchers have been able to identify genetic mutations causing several adult variants of hemochromatosis, they now must turn their attention to the normal function of these mutated genes.
These genes represent multiple steps along the pathway of iron regulation, from the body's ability to sense iron, to the body's ability to regulate uptake and storage. Working out the functions of each gene in this pathway will be an important tool for finding new methods of treating genetic disorders, as well as for understanding the basic workings of the pathway.
So though many mysteries of iron metabolism remain, the discovery of hepcidin already allows a much better understanding of the nature of iron regulation, and makes researchers optimistic that many more breakthroughs in this field are soon to come.
Porphyria cutanea tarda (commonly referred to as PCT) is recognized as the most prevalent subtype of porphyritic diseases.
The disease is characterized by onycholysis and blistering of the skin in areas that receive higher levels of exposure to sunlight. The primary cause of this disorder is a deficiency of uroporphyrinogen decarboxylase (UROD), a cytosolic enzyme that is a step in the enzymatic pathway that leads to the synthesis of heme. While a deficiency in this enzyme is the direct cause leading to this disorder, there are a number of both genetic and environmental risk factors that are associated with PCT.
Typically, patients who are ultimately diagnosed with PCT first seek treatment following the development of photosensitivities in the form of blisters and erosions on commonly exposed areas of the skin. This is usually observed in the face, hands, forearms, and lower legs. It heals slowly and with scarring. Though blisters are the most common skin manifestations of PCT, other skin manifestations like hyperpigmentation (as if they are getting a tan) and hypertrichosis (mainly on top of the cheeks) also occur. PCT is a chronic condition, with external symptoms often subsiding and recurring as a result of a number of factors. In addition to the symptomatic manifestation of the disease in the skin, chronic liver problems are extremely common in patients with the sporadic form of PCT. These include hepatic fibrosis (scarring of the liver), cirrhosis, and inflammation. However, liver problems are less common in patients with the inherited form of the disease. Additionally, patients will often void a wine-red color urine with an increased concentration of uroporphyrin I due to their enzymatic deficiency.
1- Red cell indices and blood film appearances suggest iron deficiency, although peripheral blood changes are not usually as marked as in moderate or severe iron deficiency.
2- Erythropoiesis is abnormal because of ineffective iron utilisation with poor haemoglobinisation of red cell precursors and
3- Bone marrow iron stores are normal or increased and sideroblasts may be frequent and abnormal.
Transfusional hemosiderosis is the accumulation of iron in the liver and heart but also endocrine organs, in patients who receive or did receive frequent blood transfusions (such as those with thalassemia, sickle cell disease, leukemia, aplastic anemia or myelodysplastic syndrome).
Iron-deficiency anemia is characterized by the sign of pallor (reduced oxyhemoglobin in skin or mucous membranes), and the symptoms of fatigue, lightheadedness, and weakness. None of these symptoms (or any of the others below) are sensitive or specific. Pallor of mucous membranes (primarily the conjunctiva) in children suggests anemia with the best correlation to the disease, but in a large study was found to be only 28% sensitive and 87% specific (with high predictive value) in distinguishing children with anemia [hemoglobin (Hb) <11.0 g/dl] and 49% sensitive and 79% specific in distinguishing severe anemia (Hb < 7.0 g/dl). Thus, this sign is reasonably predictive when present, but not helpful when absent, as only one-third to one-half of children who are anemic (depending on severity) will show pallor.
Because iron-deficiency anemia tends to develop slowly, adaptation occurs to the systemic effects that anemia causes, and the disease often goes unrecognized for some time. In severe cases, dyspnea can occur. Pica may also develop; pagophagia has been suggested to be "the most specific for iron deficiency."
Other possible symptoms and signs of iron-deficiency anemia include:
Porphyria cutanea tarda (PCT) is the most common subtype of porphyria. The disease is named because it is a porphyria that often presents with skin manifestations later in life. The disorder results from low levels of the enzyme responsible for the fifth step in heme production. Heme is a vital molecule for all of the body's organs. It is a component of hemoglobin, the molecule that carries oxygen in the blood.
Hepatoerythropoietic porphyria has been described as a homozygous form of porphyria cutanea tarda, although it can also be caused if two different mutations occur at the same locus.
Iron-deficiency anemia is associated with poor neurological development, including decreased learning ability and altered motor functions. Causation has not been established, but there is a possible long-term impact from these neurological issues.
Anemia of chronic disease, or anemia of chronic inflammation, is a form of anemia seen in chronic infection, chronic immune activation, and malignancy. These conditions all produce massive elevation of Interleukin-6, which stimulates hepcidin production and release from the liver, which in turn reduces the iron carrier protein ferroportin so that access of iron to the circulation is reduced. Other mechanisms may also play a role, such as reduced erythropoiesis.
Anemia of chronic inflammation is the preferred term since not all chronic diseases are associated with this form of anemia.
1- Secondary anaemias
- Chronic infection/inflammation
- Malignancy
2- Thalassaemia
3- Sideroblastic anaemia