Anemia of Chronic Disease
Anemia caused by long-term illness and inflammation
Quick Facts
- Type: Blood (anemia) condition
- Driven by: Chronic inflammation or illness
- Common with: Infections, autoimmune disease, cancer, kidney disease
- Main feature: Mild to moderate, slow-developing anemia
Overview
Anemia of chronic disease, also called anemia of inflammation, is a common type of anemia that develops in people who have a long-term illness or ongoing inflammation in the body. Anemia means there are too few healthy red blood cells to carry enough oxygen to the body's tissues.
In this condition, the underlying illness changes how the body handles iron and slows the production of red blood cells, even when there is enough iron stored in the body. The anemia is usually mild to moderate and develops gradually. Because it reflects another health problem, the key to managing it is recognizing and treating the underlying condition. It is one of the most common types of anemia, especially among people who are hospitalized or who have ongoing inflammatory illnesses, and it often improves as the main condition is brought under control.
Symptoms
Because the anemia is often mild and develops slowly, symptoms may be subtle or overlap with those of the underlying illness.
- Fatigue and low energy
- Weakness
- Paleness
- Shortness of breath with activity
- A faster heartbeat in some cases
- Difficulty concentrating
Many people have few symptoms from the anemia itself. Severe shortness of breath, chest pain, or fainting are not typical of mild anemia and should be evaluated promptly, as they may signal a more serious problem.
Causes
Anemia of chronic disease is driven by ongoing inflammation that affects red blood cell production and iron use.
- Inflammation: Long-term inflammation causes the body to lock away iron and limit its availability for making red blood cells, even when iron stores are adequate.
- Reduced red cell production: Inflammation can blunt the body's response to signals that normally stimulate red blood cell production.
- Shorter red cell survival: Red blood cells may not last as long.
Common underlying conditions include chronic infections, autoimmune diseases such as rheumatoid arthritis, cancers, and chronic kidney disease.
Risk Factors
- Chronic infections, such as long-standing infections of the lungs or bones
- Autoimmune and inflammatory conditions, such as rheumatoid arthritis or inflammatory bowel disease
- Cancer
- Chronic kidney disease
- Long-term illnesses associated with ongoing inflammation
Diagnosis
Diagnosis involves confirming anemia and identifying the underlying cause, while distinguishing it from iron deficiency anemia.
- Complete blood count (CBC): Confirms anemia and shows the size of red blood cells.
- Iron studies: Tests of iron, iron stores (ferritin), and related markers help separate anemia of chronic disease from iron deficiency. In anemia of chronic disease, iron stores are usually normal or high even though available iron is low.
- Evaluation of the underlying illness: Additional tests to find or assess the chronic condition driving the anemia.
Treatment
The most important step is treating the underlying disease, which often improves the anemia.
- Treating the cause: Controlling the infection, autoimmune disease, kidney disease, or cancer that is driving inflammation.
- Medications to stimulate red cell production: In some situations, such as chronic kidney disease, medicines that prompt the body to make more red blood cells may be used.
- Iron therapy: Iron is given only when there is true iron deficiency as well, since extra iron does not help when stores are already adequate.
- Transfusion: Reserved for severe anemia or specific situations.
Mild anemia of chronic disease often needs no specific treatment beyond managing the main illness, and it frequently improves on its own once the underlying inflammation settles down.
Prevention
- Manage chronic conditions, such as autoimmune disease, kidney disease, and infections, with appropriate care
- Keep regular follow-up appointments so anemia can be detected and monitored
- Take prescribed medications for the underlying illness as directed
- Report new or worsening fatigue and other symptoms to your healthcare provider
When to See a Doctor
See a doctor if you have ongoing fatigue, weakness, paleness, or shortness of breath, especially if you have a known long-term illness. Blood tests can determine whether anemia is present and why.
Seek urgent care for severe shortness of breath, chest pain, a very fast or irregular heartbeat, fainting, or signs of bleeding, as these may indicate severe anemia or another serious condition that needs prompt attention.
Frequently Asked Questions
What causes anemia of chronic disease?
It is caused by long-term inflammation from an underlying illness, such as a chronic infection, autoimmune disease, cancer, or kidney disease. The inflammation makes the body hold back iron and slow red blood cell production, leading to anemia even when iron stores are adequate.
How is it different from iron deficiency anemia?
In iron deficiency anemia, the body is actually low on iron. In anemia of chronic disease, iron stores are usually normal or high, but the iron is locked away and not available for making red blood cells. Blood tests of iron and ferritin help tell the two apart, which matters because the treatments differ.
Will taking iron supplements help?
Usually not, unless you also have true iron deficiency. In anemia of chronic disease the body already has enough stored iron, so extra iron does not correct the problem and is generally avoided unless testing shows a real deficiency.
How is it treated?
The main treatment is managing the underlying illness driving the inflammation, which often improves the anemia. In certain conditions such as chronic kidney disease, medicines that stimulate red blood cell production may be used, and transfusion is reserved for severe cases.
Is anemia of chronic disease dangerous?
It is usually mild to moderate and not dangerous on its own, but it signals an underlying condition that needs attention. Seek urgent care for severe shortness of breath, chest pain, fainting, or signs of bleeding, which may indicate a more serious problem.
References
- National Heart, Lung, and Blood Institute (NHLBI). Anemia.
- MedlinePlus, U.S. National Library of Medicine. Anemia of chronic disease.
- Mayo Clinic. Anemia.
- National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). Anemia in chronic kidney disease.