Blood, Anemia, Leukemia, and Blood Tests
Treatment of anemia & leukemia
Kristen Danielle Go and Samuel Lam
Learning Objectives
By the end of this section, you will be able to:
- List common nutritional treatments for anemia
- Identify appropriate treatments depending on the severity of anemia
- Briefly describe the treatment for leukemia with respects to eradication of leukemic cells
Treatment for Anemia
Anemia is caused when hemoglobin drops, and its symptoms are a result of the decreased delivery of oxygen and other vital materials carried by blood. Treatments focus on correcting this hemoglobin and red blood cell deficiency by addressing the underlying cause. Recall the main types of anemia from the previous chapter “Pathophysiology of Anemia”. If the anemia is non-urgent (ie not causing significant impact on tissue oxygenation), the treatment is to increase the body’s natural production of red blood cells. If the anemia is causing complications in other organs, more serious interventions will be considered.
Collaboration with multiple health care providers is key to a patient’s recover (e.g. medical lab technologist, nutritionist, pharmacist, hematologist, transfusion technologist)
Treatment for Anemia due to impaired Hb or RBC synthesis
Treatments address the decreased number of hemoglobin and/or red blood cells in a number of ways:
- Directly – by providing the patient with a blood transfusion to raise their blood cell and hemoglobin levels, or
- Indirectly – by administering nutrition and medications to stimulate synthesis of new hemoglobin and blood cells within the patient.
Below are methods used to indirectly increase hemoglobin and/or RBC synthesis
Treatment for iron deficiency anemia: supplementation with iron, Vitamin B12, and folate
In patients with anemia due to insufficient blood production, the underlying cause is often due to a deficiency in a component needed in the assembly of new blood cells. Treatment for this can involve treating the deficiency by supplementing the insufficient component.
Iron-deficiency anemia can be treated with iron supplements, which can be obtained over the counter in tablet form or liquid form for children. Iron is incorporated into hemoglobin — the functional unit of a red blood cell that is responsible for carrying oxygen. In iron-deficiency anemia, red blood cells are underfilled with hemoglobin, resulting in smaller than normal red blood cells with diminished oxygen-carrying capacity. As non-heme iron (i.e. iron that isn’t already part of hemoglobin as in meat products with blood) can be difficult to absorb, it can be recommended to combine the intake of iron supplements with vitamin C.
Vitamin B12 and Vitamin B9 (also known as folate or folic acid), are both also components needed for DNA and cell synthesis to make healthy, functioning red blood cells. Sufficient amounts prompt normal hematopoiesis and the complete development into fully functional mature blood cells. Without Vitamin B12 and folate, all blood cells, especially RBCs, remain undivided and large, resulting in premature destruction in the spleen.
Diet is a major source of the components needed to build new red blood cells. Dietary changes to increase intake of the missing vitamins may also contribute to treating anemia. Food sources rich in iron include red meat, spinach, and beans. Vitamin B12 can be found in seafood, dairy, and other animal derived products, meaning that individuals with vegan diets often have minimal sources of Vitamin B12. Folate can be obtained from food sources such as broccoli and bananas, and is also commonly added to enriched breads, cereals, and pastas. A referral to a dietitian for a consult may be provided to aid in ensuring that dietary needs are met.
Vitamin B12 and folate may also be prescribed in tablet form. If dietary sources of Vit B12 is insufficient and/or there are issues with gastrointestinal absorption, Vitamin B12 can be administered by injections. In many cases, vitamin B12 shots are needed as a regular, lifelong treatment if the underlying cause of the deficiency cannot be cured.
Treatment for anemia due to lack of erythropoiesis
If all key red blood cell building blocks are present in sufficient amounts AND the bone marrow is functional, anemia can be addressed by administering the hormone erythropoietin, which stimulates erythropoiesis to increase the patient’s red blood cell count. Erythropoietin is normally made in the kidneys (see Acute Kidney Injury Chapter for review) and kidney disease can cause anemia due to decreased erythropoiesis.
Treatment for anemia due to RBC loss or destruction
If the anemia were due to blood loss or destruction, the treatment would be to stop that loss/destruction AND promote increased synthesis of hemoglobin as previously stated. As the causes for blood loss are many (e.g. trauma, occult bleed in GI system), this text can not comment on treatment, other than stopping the bleed. Similarly, there are many causes for RBC destruction (e.g. autoimmune, infectious, RBC structural defects, vascular defects) which discussion about treatments are beyond the scope of this book.
Blood Transfusions
Regardless of the cause, if the anemia is severe enough to impact organ function and below a certain threshold for hemoglobin amount, anemic patients can receive additional blood in the form of red blood cell transfusions. Prior to transfusion, the patient’s blood type will need to be determined and matched to a donor blood type to prevent hemolytic reactions. Packed red blood cells are obtained by removing plasma, white blood cells, and other blood components from whole blood. Packed red blood cells are usually used in transfusions for anemia patients to minimize risks associated with fluid overload or hemolytic reactions in the recipient.
However, blood transfusions are more invasive compared to the previously mentioned anemia treatments, and are associated with more possible complications. Because of this, blood transfusions for deficiency related anemias are only administered in more severe cases.
Treatment of leukemia
The goal of leukemia treatment is to stop and eradicate the leukemic blasts within the bone marrow AND encourage the synthesis and function of the normal blood cells. Thus, in addition to the cancer treatments listed below, treatment will also include supportive therapy (ie. transfusion of RBCs and/or platelets or drugs to augment the white blood cell count.
As bone marrow is the site of pathology, treatment of leukemia is focussed here. However, because bone marrow is in many bones, a localized target for eradication, as with radiation therapy focussed on a single spot in bone, isn’t likely. Thus, eradication must be done throughout the entire body via chemotherapy.
Chemotherapy
- Chemotherapy uses drugs to kill leukemia cells, it can consist of one of multiple types of chemicals. Chemotherapy drugs are often injected into bloodstream, and travels along body to kill malignant cells. These drugs could also affect some normal cells and cause many side effects such as hair loss, fatigue, nausea. With recent advances, we have more targeted therapy to the malignant cancer cells that may harbour certain chromosomal abnormalities or mutations.
Bone marrow or stem cell transplant
- Bone marrow transplant can be used on acute leukemia patients via donation of healthy hemtaopoietic stem cells. High doses of chemotherapy are often performed to kill leukemia cells and marrow before patients are infused with donor hematopoietic stem cells via intravenous (IV) catheter.
Immunotherapy
- Recent developments of targeted therapy by using monoclonal antibodies to target specific cell surface markers which are exhibited on the leukemic cell line.
Section Review
- Anemia treatments all increase red blood cell counts, although the means will vary depending on the specific type of anemia the patient has. The treatments will aim to address the underlying cause of the low level of red blood cells that may have been caused by decreased blood cell production, increased blood cell destruction, or blood loss.
- Insufficient red blood cell constituents — such as iron, Vitamin B12, and folate — can be corrected by administering the missing nutrients or by increasing dietary intake.
- In cases that cannot be corrected by administering drugs, red blood cell counts can be increased via a blood transfusion of packed red blood cells.
- The hormone erythropoietin may also be administered to stimulate synthesis of new red blood cells in the individual.
- The goal of leukemia treatment is to stop the proliferation of the leukemic blasts within the bone marrow by localized (radiotherapy), systemic (chemotherapy), and immunologic methods.
- After eradication of leukemic blasts, bone marrow transplants encourage the synthesis and function of the normal blood cells.