Lack of intrinsic factor

• Alternative Names

  Intrinsic factor - lack of

• Causes, incidence, and risk factors

  Babies that are born without intrinsic factor cannot properly absorb vitamin B12 starting around age 6 months. Children who have the juvenile type of lack of intrinsic factor tend to show signs and symptoms after age 10.

  Older adults get pernicious anemia, which is caused by a lack of intrinsic factor production. This is usually due to an autoimmune disease that causes the stomach lining to waste away (atrophy). The stomach lining is where intrinsic factor is usually made.

• References

  Antony AC. Megaloblastic anemias. In: Hoffman R, Benz EJ, Shattil SS, et al., eds. Hematology: Basic Principles and Practice. 5th ed. Philadelphia, Pa: Churchill Livingstone; 2008:chap 39.

Review Date: 1/31/2010

Reviewed By: Yi-Bin Chen, MD, Leukemia/Bone Marrow Transplant Program, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.