3600 – Anti-Intrinsic Factor

Highlights

• Use of recombinant, human intrinsic factor
• Ready-to-use (exception: wash buffer) and barcoded reagents
• Quality assured handling in routine laboratories
• Short incubation times (60 min / 30 min / 15 min) at room temperature
• Quantitative determination of IgG antibodies
• Calibrated by use of an internal reference sample
• Results expressed in U/mL
• Excellent diagnostic sensitivity and specificity
• High precision within the measurement range
• CE marked
• Automatable

Intended Use

The Anti-Intrinsic Factor is a quantitative enzyme-linked immunosorbent assay (ELISA) for the determination of IgG antibodies against intrinsic factor in human serum. The Anti-Intrinsic Factor is intended as an aid in the diagnosis of pernicious anemia and autoimmune gastritis in conjunction with other clinical and laboratory findings. The immunoassay is designed for manual professional in vitro diagnostic use.

Diagnostic Relevance

Pernicious anemia (Biermer‘s disease) is based on an undersupply of vitamin B12, which in turn can be due to a lack of intrinsic factor. Vitamin B12 and the Intrinsic Factor Vitamin B12 is essential for the formation of blood cells. Microorganisms produce vitamin B12, which humans ingest with food. Proteolytic processes in the stomach release the vitamin, where it binds to intrinsic factor (IF). Parietal cells of the gastric mucosa produce intrinsic factor, a glycoprotein that protects vitamin B12 from decomposition and enables its absorption in the small intestine. A lack of intrinsic factor can lead to an undersupply of vitamin B12 and thus to pernicious anemia.

Type A gastritis is a chronic autoimmune disease in which antibodies against parietal cells and intrinsic factor attack the gastric mucosa. The destruction of the parietal cells leads to a reduced absorption of vitamin B12 and thus to its undersupply due to a lack of intrinsic factor. Genetic causes, the surgical removal of a section of the stomach and chronic inflammation of the gastric mucosa can also result in a lack of intrinsic factor. A lack of vitamin B12 can also be triggered by medication or a diet that is too one-sided and therefore unbalanced.

Clinical Symptoms

Typical symptoms of pernicious anemia are fatigue, increased heart rate and paleness as a result of the anemia. Indigestion and abdominal pain also occur. Neurological symptoms such as numbness in the hands and feet, unsteady gait, coordination disorders or paralysis often occur without signs of anemia. Visual disturbances or the picture of a polyneuropathy are also possible. Poor concentration, depression and psychoses, schizophrenia and dementia have also been described. Pernicious anemia can progress to funicular myelosis.

Diagnostic Approach

The diagnosis of pernicious anemia is based on the clinical symptoms and numerous laboratory diagnostic tests. Autoimmune disease detection involves the determination of antibodies against parietal cells, the gastric H⁺/K⁺ ATPase, and intrinsic factor.