From the Guidelines
Normochromic normocytic anemia is primarily caused by conditions such as acute blood loss, chronic disease, bone marrow failure, hemolysis, endocrine disorders, and nutritional deficiencies, with chronic kidney disease being a significant cause due to decreased erythropoietin production, as supported by 1.
Causes of Normochromic Normocytic Anemia
The causes of normochromic normocytic anemia can be multifactorial and include:
- Acute blood loss
- Chronic disease (infections, inflammatory disorders, kidney disease, malignancies)
- Bone marrow failure (aplastic anemia, leukemia, myelodysplastic syndromes)
- Hemolysis (autoimmune hemolytic anemia, microangiopathic hemolytic anemia, hereditary spherocytosis)
- Endocrine disorders (hypothyroidism, hypopituitarism)
- Nutritional deficiencies in their early stages
- Chronic kidney disease due to decreased erythropoietin production, as noted in 1
- Certain medications like chemotherapy agents, antiretrovirals, and immunosuppressants that suppress bone marrow function, as discussed in 1
Diagnosis and Treatment
Diagnosis requires a complete blood count showing normal MCV (80-100 fL) and normal MCHC (32-36%), followed by additional tests to determine the underlying cause, as outlined in 1. Treatment focuses on addressing the primary condition rather than the anemia itself, though transfusions may be needed for severe cases. Understanding the pathophysiology of each cause is essential for proper management, as the anemia reflects an underlying disorder affecting either red blood cell production, destruction, or blood loss without affecting cellular characteristics.
Key Considerations
It is crucial to identify and address the underlying cause of normochromic normocytic anemia, as treatment of the primary condition can lead to resolution of the anemia. In cases of chronic kidney disease, management of anemia may involve the use of erythropoietin-stimulating agents and iron supplementation, as recommended in 1. For patients with cancer or undergoing chemotherapy, management of anemia may involve blood transfusions, erythropoietin-stimulating agents, and iron supplementation, as discussed in 1.
From the Research
Causes of Normochromic Normocytic Anemia
The causes of normochromic normocytic anemia can be diverse and include:
- Chronic disease, which is often mistaken for iron-deficiency anemia 2
- Drug therapy 2
- Chronic renal failure, where the glomerular filtration rate drops below 20-30 ml/min 3
- Anemia of inflammation 4
- Hemolytic anemia 4
- Acute blood loss anemia 4
- Aplastic anemia 4
- Normochromic normocytic anemia of unknown cause, which is encountered infrequently in clinical practice and is found mainly in older patients 5
Underlying Mechanisms
The underlying mechanisms of normochromic normocytic anemia can include:
- A moderately reduced red cell life span 3
- Blood loss 3
- An inadequate increase in erythropoiesis relative to the fall in hemoglobin (Hb) 3
- A failure to increase erythropoietin (EPO) production in response to the developing anemia 3, 6
- Reduced iron availability, inadequate dialysis, infection, and hyperparathyroidism, which can all impair the efficacy of EPO 3
Diagnosis and Management
Diagnosis and management of normochromic normocytic anemia should focus on:
- Confirming the diagnosis and determining the morphologic type of anemia 2
- Excluding correctable causes of the anemia through noninvasive evaluation 5
- Managing the underlying condition, such as chronic kidney disease or anemia of inflammation 4
- Using erythropoiesis-stimulating agents in patients with anemia due to chronic kidney disease, but only in symptomatic patients with a hemoglobin level less than 10 g/dL 4