Two major raw materials are needed for hematopoiesis, namely erythropoietin (EPO) and iron. Anemia has a wide range of effects on dialysis patients, including reducing exercise tolerance, work ability, appetite, nutrition, and quality of life. The kidneys of patients with renal failure are damaged and cannot produce enough erythropoietin, so anemia is common. Iron is the raw material for making red blood cells, and erythropoietin is produced in the kidneys, which stimulates the bone marrow to use iron to make red blood cells.

Causes of anemia in renal failure patients

• Insufficient production of red blood cells (EPO deficiency).
• The life span of red blood cells is shortened (the average life expectancy of red blood cells in normal people is 120 days, while that in dialysis patients is only 70 to 80 days).
• Iron deficiency.
• Folic acid or vitamin B12 deficiency.
• Gastrointestinal hemorrhage, it can be seen that the black stool is resolved, or the fecal occult blood reaction is positive.
• Malnutrition

Anemia treatment principles

• The principle of treating renal anemia is to maintain the patient's hemoglobin (Hgb, hemoglobin) above 11 to 12 g/dl and hematocrit (Hct, hematocrit) at about 33 to 36%.
• Physicians' evaluation of anemia patients will include tests for fecal occult blood reaction, hemoglobin, reticulocyte count, and iron storage in the body.

EPO use

• EPO is often used to treat renal anemia. During treatment, some patients will have cold symptoms such as muscle pain. The onset time is usually 60 to 90 minutes after intravenous injection. The symptoms are not serious and usually disappear after continuous use of EPO. This side effect occurs less frequently with injections.
• Another possible side effect is high blood pressure, which usually occurs in 1/3 of patients when the hematocrit is higher than 30. The side effects can be treated by changing the dose of EPO or increasing blood pressure drugs under the doctor's instructions.
• Hemoglobin or hematocrit should be tracked regularly after EPO use. When anemia does not improve after 2 to 4 weeks of EPO treatment, the dose of EPO should be increased. If the target value of hemoglobin has been reached, the dose can be reduced. A small number of patients will develop resistance after long-term use of ESA. At this time, it is necessary to find possible causes. The common cause is insufficient dialysis volume, and the rare cause is some liver tumors.

When should I take iron supplements?

• If the patient's transferrin saturation (transferrin saturation) is lower than 20%, or serum ferritin (ferritin) is lower than 500 ng/ml, iron therapy should be started. When transferrin saturation is higher than 50 %, or serum ferritin is higher than 800 ng/ml, iron treatment should be stopped for 3 months and reassessment should be made to avoid excessive iron in the body.

Epilogue

• Anemia is a common problem in patients with chronic kidney disease. The most important principle in the treatment of renal anemia is that the amount of dialysis should be sufficient. Adequate dialysis, moderate EPO and iron supplementation can resolve most anemias. If there is anemia that is not easy to improve, you should carefully find the cause and correct it.