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Vitamin B12 deficiency Vitamin B12, also called cobalamin, is necessary for the production of red blood cells and plays an important role in maintaining the health of nerve cells and in the formation of genetic material. It is a water-soluble vitamin found in certain foods: meat, fish, milk products and eggs. Vegetables alone are an inadequate source of vitamin B12. Initial symptoms of vitamin B12 deficiency include dizziness and fatigue. Untreated deficiency can result in anaemia and damage to the nervous system.  Intramuscular vitamin B12 injections form the basis of most treatment plans. Causes Vitamin B12 deficiency is most commonly caused by a lack of intrinsic factor - a substance produced in the stomach that is necessary for the absorption of vitamin B12 from food. When intrinsic factor is lacking, vitamin B12 is unable to be absorbed and is therefore unable to be utilised by the body. Pernicious anaemia is one such condition where the product...

Leukaemia – symptoms, diagnosis, treatment Leukaemia /Blood Cancer is a general name for a group of cancers that originate in the bone marrow and cause abnormal blood cell production. Cure can be achieved in some forms of the disease but treatment options and outcomes will depend on a range of factors, including the type of leukaemia, the extent of the disease and the age and health of the patient. What is leukaemia? Bone marrow is soft, “spongy” material in our bones that in healthy people produces a steady supply of new blood cells (including red blood cells that carry oxygen around the body, white blood cells that help fight infection, and platelets that have a role in blood clotting).  In people with leukaemia, the bone marrow produces large numbers of abnormal white blood cells that grow and multiply “out of control”. These abnormal cells may not function properly and may affect the ability of normal blood cells to perform their usual functions.  There are many typ...

Congenital dyserythropoietic anemia Congenital dyserythropoietic anemia (CDA) is a rare blood disorder, similar to the thalassemias. CDA is one of many types of anemia, characterized by ineffective erythropoiesis, and resulting from a decrease in the number of red blood cells (RBCs) in the body and a less than normal quantity of hemoglobin in the blood. Signs/symptoms The symptoms and signs of congenital dyserythropoietic anemia are consistent with: Tiredness (fatigue) Weakness Pale skin Types Congenital dyserythropoietic anemia type I-is defined by moderate to severe macrocytic anemia (commonly in neonates as intrauterine growth retardation). Congenital dyserythropoietic anemia type II-is defined by moderate anemia, splenomegaly, and hepatomegaly. Congenital dyserythropoietic anemia type III- is defined by mild anemia and retinal degeneration. Congenital dyserythropoietic anemia type IV- is defined by having severe anemia at birth (type V and VI are reco...

Fanconi anemia Fanconi anaemia (FA) is a rare genetic disease. Among those affected the majority develop cancer, most often acute myelogenous leukemia, and 90% develop bone marrow failure (the inability to produce blood cells) by age 40. About 60–75% of people have congenital defects, commonly short stature, abnormalities of the skin, arms, head, eyes, kidneys, and ears, and developmental disabilities. Around 75% of people have some form of endocrine problem, with varying degrees of severity. FA is the result of a genetic defect in a cluster of proteins responsible for DNA repair. Treatment with androgens and hematopoietic (blood cell) growth factors can help bone marrow failure temporarily, but the long-term treatment is bone marrow transplant if a donor is available. Because of the genetic defect in DNA repair, cells from people with FA are sensitive to drugs that treat cancer by DNA crosslinking, such as mitomycin C. The typical age of death was 30 years in 2000. FA ...

Myelophthisic anemia Myelophthisic anemia (or myelophthisis) is a severe type of anemia found in some people with diseases that affect the bone marrow. Myelophthisis refers to the displacement of hemopoietic bone-marrow tissue either by fibrosis, tumors or granulomas. The word comes from the roots myelo-, which refers to bone marrow, and phthysis, shrinkage or atrophy. Causes Myelophthisis can occur in the setting of chronic myeloproliferative disease (e.g. myelofibrosis), leukemia, lymphoma, and metastatic carcinoma or myeloma. It is common in people who have chronic idiopathic myelofibrosis. It has been linked to small-cell lung cancer, breast cancer or prostate cancer that metastasizes to the bone marrow. Historically, the most common cause of displacement of healthy bone marrow was tuberculosis.  Currently, the most common cause is displacement of bone marrow by metastatic cancer (extramedullary hematopoiesis tends to be modest). Other causes include myeloprol...

Vitamin B12 deficiency anemia  Vitamin B12 deficiency anemia, of which pernicious anemia is a type, is a disease in which not enough red blood cells are present due to a lack of vitamin B12.The most common initial symptom is feeling tired. Other symptoms may include shortness of breath, pale skin, chest pain, numbness in the hands and feet, poor balance, a smooth red tongue, poor reflexes, depression and confusion.Without treatment some of these problems may become permanent. Although pernicious anemia technically refers to cases resulting from not enough intrinsic factor, it is often used to describe all cases of anemia due to not enough vitamin B12. Lack of intrinsic factor is most commonly due to an autoimmune attack on the cells that create it in the stomach. It can also occur following the surgical removal of part of the stomach or from an inherited disorder.Other causes of low vitamin B12 include not enough dietary intake (such as in a vegan diet), celiac disease, or ...

Megaloblastic anemia Megaloblastic anemia (or megaloblastic anaemia) is an anemia (of macrocytic classification) that results from inhibition of DNA synthesis during red blood cell production. When DNA synthesis is impaired, the cell cycle cannot progress from the G2 growth stage to the mitosis (M) stage. This leads to continuing cell growth without division, which presents as macrocytosis. Megaloblastic anemia has a rather slow onset, especially when compared to that of other anemias. The defect in red cell DNA synthesis is most often due to hypovitaminosis, specifically a deficiency of vitamin B12 and/or folic acid. Vitamin B12 deficiency alone will not cause the syndrome in the presence of sufficient folate, as the mechanism is loss of B12 dependent folate recycling, followed by folate-deficiency loss of nucleic acid synthesis (specifically thymine), leading to defects in DNA synthesis. Folic acid supplementation in the absence of vitamin B12 prevents this type of anemia (althou...