Intrinsic Factor Deficiency

Intrinsic factor deficiency is a rare condition that is characterized by pernicious anemia and neurological abnormalities. Most affected people develop signs and symptoms of the condition before age 5 years which may include failure to thrive and symptoms related to anemia (i.e. fatigue, pale skin, etc). Without early diagnosis and treatment, nervous system damage may occur which can be associated with confusion; depression; and numbness or tingling in the hands and/or feet. Intrinsic factor deficiency is caused by changes (mutations) in the GIF gene and is inherited in an autosomal recessive manner. Treatment generally consists of vitamin B12 injections.