What is the diagnosis and treatment for anemia?

From the Guidelines

Anemia should be diagnosed and treated based on its underlying cause, with iron deficiency anemia being the most common type, and treatment typically involving oral iron supplements, such as ferrous sulfate 325mg taken once or twice daily between meals with vitamin C to enhance absorption, as recommended by the British Society of Gastroenterology guidelines 1.

Diagnosis of Anemia

Anemia is a condition characterized by a deficiency of red blood cells or hemoglobin in the blood, resulting in reduced oxygen delivery to tissues. The diagnosis of anemia can be made by measuring hemoglobin (Hb) concentration or hematocrit (Hct) levels, although these measures cannot determine the cause of anemia 1. To differentiate between iron-deficiency anemia and anemia due to other causes, laboratory tests such as mean cell volume, red blood cell distribution width, and serum ferritin concentration can be used 1.

Treatment of Iron Deficiency Anemia

For iron deficiency anemia, the most common type, oral iron supplements such as ferrous sulfate 325mg taken once or twice daily between meals with vitamin C to enhance absorption is typically recommended 1. Treatment usually continues for 3-6 months after hemoglobin normalizes to replenish iron stores. In patients with inflammatory bowel disease (IBD), intravenous iron may be considered as first-line treatment, especially in those with clinically active IBD, previous intolerance to oral iron, or hemoglobin below 100 g/L 1.

Treatment of Other Types of Anemia

For vitamin B12 deficiency anemia, cyanocobalamin 1000mcg daily orally or monthly injections may be prescribed. Folate deficiency requires folic acid supplements of 1mg daily. Severe anemia with hemoglobin below 7g/dL or symptomatic patients may require blood transfusions. Underlying causes like gastrointestinal bleeding, malabsorption, or chronic diseases must be addressed simultaneously.

Dietary Changes and Supportive Care

Dietary changes including iron-rich foods (red meat, spinach, beans), vitamin C sources to enhance iron absorption, and B12-rich foods (meat, eggs, dairy) can support medical treatment. Anemia develops when the body either cannot produce enough healthy red blood cells, destroys too many red blood cells, or loses too much blood, disrupting the oxygen transport system essential for cellular function throughout the body. Some key points to consider in the treatment of anemia include:

• Assessing for the presence of anemia in all patients with IBD, regardless of age 1
• Using complete blood count, serum ferritin, and C-reactive protein for laboratory screening 1
• Considering intravenous iron as first-line treatment in patients with clinically active IBD or previous intolerance to oral iron 1
• Re-treating with intravenous iron as soon as serum ferritin drops below 100 mg/L or hemoglobin below 12 or 13 g/dL according to gender 1

From the FDA Drug Label

1 INDICATIONS AND USAGE 1.1 Anemia Due to Chronic Kidney Disease PROCRIT is indicated for the treatment of anemia due to chronic kidney disease (CKD), including patients on dialysis and not on dialysis to decrease the need for red blood cell (RBC) transfusion.

1. 2 Anemia Due to Zidovudine in Patients with HIV Infection PROCRIT is indicated for the treatment of anemia due to zidovudine administered at ≤ 4200 mg/week in patients with HIV Infection with endogenous serum erythropoietin levels of ≤ 500 mUnits/mL.

2. 3 Anemia Due to Chemotherapy in Patients with Cancer PROCRIT is indicated for the treatment of anemia in patients with non-myeloid malignancies where anemia is due to the effect of concomitant myelosuppressive chemotherapy, and upon initiation, there is a minimum of two additional months of planned chemotherapy.

The diagnosis of anemia is not explicitly stated in the label, but it can be inferred that anemia is characterized by a low hemoglobin level, which may be due to various causes such as chronic kidney disease, zidovudine administration in HIV infection, or chemotherapy in cancer patients. The treatment for anemia, as indicated in the label, is the use of epoetin alfa (PROCRIT) to decrease the need for red blood cell (RBC) transfusions. The dosing should be individualized and the lowest dose sufficient to reduce the need for RBC transfusions should be used 2.

• Key considerations for treatment include:
  • Evaluating iron stores and nutritional factors before and during treatment
  • Administering supplemental iron therapy when necessary
  • Monitoring response to therapy and adjusting the dose as needed
  • Correcting or excluding other causes of anemia before initiating PROCRIT

From the Research

Diagnosis of Anemia

• Anaemia is typically diagnosed through a combination of haemoglobin measurement and measures of iron-deficient erythropoiesis, such as transferrin iron saturation and mean corpuscular haemoglobin concentration 3
• The optimal diagnostic approach is to measure the serum ferritin as an index of iron stores and the serum transferrin receptor as an index of tissue iron deficiency 3
• Distinguishing iron deficiency from other causes of anemia is integral to initiating the appropriate treatment 4
• In the elderly, differential diagnosis of anaemia is more challenging due to the presence of multiple dysfunctions, and soluble transferrin receptor and hepcidin are useful parameters for differential diagnosis 5

Treatment of Anemia

• The treatment of iron deficiency should always be initiated with oral iron, and parenteral iron can be given when oral iron fails due to large blood losses, iron malabsorption, or intolerance to oral iron 3
• In iron deficiency anaemia, the first step other than causal treatment is to replace iron orally, and intravenous iron replacement therapy is indicated if oral iron is not tolerated or does not lead to a sufficient rise in the haemoglobin level 5
• Folic acid deficiency is generally treated orally, whereas vitamin B12 deficiency is generally treated by the parenteral route 5, 6
• The goal of treatment is correction of anaemia by supplementation of iron and vitamins, and the route of iron and vitamin supplementation is guided by the severity of anaemia 7
• Treatment of anaemia due to chronic renal failure and anaemia due to myelodysplastic syndromes involves treating the underlying cause and using erythropoiesis-stimulating agents if indicated 5