Anti-intrinsic factor antibodies
What is being analysed?
Anti-intrinsic factor antibodies (AIFAs) are antibodies produced by the immune system that target intrinsic factor, a protein essential for the absorption of vitamin B12 in the small intestine.
What does the result mean?
A positive result for AIFA indicates the presence of antibodies that may interfere with the normal function of intrinsic factors, potentially leading to impaired absorption of vitamin B12. This can result in vitamin B12 deficiency, which can manifest as symptoms such as fatigue, weakness, neurological problems, and anaemia.
Why do the analysis?
The analysis of AIFA is crucial in diagnosing the cause of vitamin B12 deficiency, particularly when other common causes, such as dietary insufficiency or malabsorption disorders, have been ruled out. Identifying AIFA helps doctors determine the appropriate treatment and management strategies for patients with vitamin B12 deficiency.
When to do the analysis?
AIFA analysis is typically recommended when vitamin B12 deficiency is suspected and other potential causes have been investigated. Symptoms such as fatigue, weakness, tingling sensations, and neurological abnormalities may prompt healthcare providers to order AIFA testing.
What sample is required?
A blood sample is required for AIFA analysis. The sample is usually drawn from a vein in the arm using a needle.
Is any type of prior preparation necessary?
No specific prior preparation is typically necessary for AIFA analysis. However, it is essential to follow any instructions provided by healthcare providers or the testing facility regarding fasting or medication restrictions, if applicable.
How is it used?
AIFA analysis is used as part of the diagnostic process for vitamin B12 deficiency. It helps confirm whether autoimmune mechanisms, specifically the production of antibodies against intrinsic factor, are contributing to the deficiency. This information guides healthcare providers in developing an appropriate treatment plan, which may include vitamin B12 supplementation and addressing underlying autoimmune conditions.
What are the normal values?
The normal range for AIFA levels in the blood is typically reported as negative, indicating the absence of detectable antibodies against intrinsic factors.
What does it mean to have altered values?
Elevated levels of AIFA in the blood indicate a positive result, suggesting the presence of antibodies against intrinsic factors. This may impair the binding of intrinsic factors to vitamin B12, leading to reduced absorption and subsequent deficiency. Treatment strategies may involve vitamin B12 supplementation, as well as addressing any underlying autoimmune conditions contributing to the production of AIFA.
Table: AIFA analysis reference values
AIFA Result
Interpretation
Negative
Absence of AIFA
Positive
Presence of AIFA
Understanding anti-intrinsic factor antibodies is crucial in diagnosing and managing vitamin B12 deficiency effectively. AIFA analysis provides valuable insights into the underlying mechanisms contributing to vitamin B12 deficiency, enabling targeted treatment approaches for affected individuals.