Anemia - Introduction

Causes of Folate Deficiency. The body stores only about 100 times its daily requirements for folate and can exhaust this supply within about3 months if the diet is deficient in folate.

Poor diet coupled with alcoholism is the most common cause of folate deficiency. Alcohol abuse not only contributes to malnutrition, but alcohol causes chemical changes that can result in lower folate levels.

Any condition that disturbs the small intestine and impairs its absorption ability can cause a deficiency. Such disorders include:

Inflammatory bowel disease
Celiac sprue (a sensitivity reaction to gluten)

Click the icon to see an image of foods that contain gluten.

Parasitic diseases such as giardiasis
Short bowel syndrome

Deficiencies can also be caused by high demand for folic acid caused by conditions such as cancer, pregnancy, severe psoriasis, severe hyperthyroidism, and hemolytic anemia. Some drugs, including Dilantin, methotrexate, trimethoprim, and triamterene, may also hinder folate absorption.

Less Common Anemias
Form of Anemia	Description and Diagnosis	Causes and Risk Factors	Treatments
Aplastic Anemia	Bone marrow fails to produce all types of blood cells. Symptoms in addition to standard anemia are bleeding in mucous membranes and skin, gingivitis, higher risk for infection, and shortness of breath.	Cause is unknown in half the cases. Known causes include hereditary conditions (e.g., Fanconi's anemia), viruses (e.g., HIV, hepatitis, Epstein-Barr), autoimmune diseases (e.g., lupus, rheumatoid arthritis), medications (e.g., valproic acid, tacrolimus, azathioprine) or chemicals (e.g., benzene, pesticides).	Transfusions, antibiotics, bone marrow or stem cell transplantation, immunosuppressant drugs. (Formerly the anemia was nearly always fatal, but survival rates now can reach 92% with successful transplants and up to 87% with immunosuppressants.)
Thalassemia	Genetic blood disease caused by a defect in the rate of production of hemoglobin. The two major forms are thalassemia minor and thalassemia major (Cooley's anemia, beta thalassemia). Thalassemia minor is the more common and milder form, in which life span is normal. Thalassemia major can be serious but it is fortunately very rare.	Affects males and females equally. Most common in people of Mediterranean descent, especially Italians and Greeks. Both types of thalassemia are found in an area that extends from northern Africa and southern Europe to Thailand, including Iran, Iraq, Indonesia, and southern China. Thalassemia major is more common in families who intermarry.	Transfusions to supply enough red blood cells to achieve moderate anemia and avoid iron overload are standard approaches for thalassemia major. Investigation ongoing to find alternatives to transfusions. Hydroxyurea may help some patients. Bone marrow transplantation may be needed. No treatment necessary for thalassemia minor.
Hemolytic Anemias: Acquired	Anemia caused by hemolysis (premature destruction of red blood cells). Diagnosis considered when there is marked increase in RBC production by bone marrow.	Autoimmune hemolytic anemia is the primary type, in which antibodies produced by the immune system damage RBCs. Cause unknown or associated with disorders such as systemic lupus erythematosus or lymphoma. Other causes are high exposure to certain metals or chemicals (e.g., lead, copper, benzene, naphthalene), snake and insect bites, malaria, transfusions, post-surgical complications, and drugs such as methyldopa. In infants, blood group incompatibility between mother and child or infections in the womb.	Corticosteroids for autoimmune hemolytic anemia. Transfusions beneficial in many cases.
Hemolytic Anemias: Inherited	Hemolysis (premature destruction of RBCs) caused by sphere-shaped RBCs, which have difficulties circulating through the spleen.	Inherited defects include membrane defects, hemoglobin abnormalities, and enzyme deficiencies. Fava beans may trigger symptoms. More likely and more serious in males than females.	Blood transfusions may be necessary for some types of hemolytic anemia. Experimental trials use immune globulin. Removal of the spleen (splenectomy) or bone marrow transplantation may help some patients.
Sideroblastic Anemias	Group of anemias caused by impaired ability of bone marrow to produce normal RBCs. Normal to high iron levels, but iron cannot be used to make hemoglobin. In addition to the standard symptoms of anemia are jaundice, enlarged liver and spleen, fever, headache, loss of appetite, vomiting, and leg sores. Symptoms can be mild. Usually appears in childhood. Infections, trauma, and pregnancy may trigger symptoms.	Inherited or acquired after excessive alcohol use, certain medications, including chloramphenicol, or other disorders, including some cancers and rheumatoid arthritis. More common in the elderly.	Deferoxamine (Desferal) is used to remove iron. Effectiveness is increased when ascorbate is added to the regimen. Folate and pyridoxine are used, but their effectiveness is under question.
Sickle Cell Anemia	Serious, life-threatening, inherited disease. The sickle-shaped, inflexible RBC has impaired ability to squeeze through vessels. Short life span of RBC (10-20 days) causes anemia. In addition to anemia symptoms, joint and bone pain, infections, and heart failure can occur.	Disease occurs in 0.6% and the trait is found in the genetic makeup of 9% of African Americans. Also occurs in people from India and Spanish-speaking and Mediterranean regions.	Measures to avoid cycling and control pain. Including hydration, hydroxyurea, NSAIDs and narcotic analgesics. Bone marrow transplantation. [See In-Depth Report #58: Sickle-Cell Disease.]