CPT® Code 83528

The CPT® Code 83528 refers to a laboratory test specifically designed to measure the level of intrinsic factor (IF) in the body. Intrinsic factor is a crucial glycoprotein that is produced by the parietal cells located in the stomach lining. This protein plays an essential role in the absorption of vitamin B12, also known as cobalamin, within the intestine. The presence and levels of intrinsic factor are vital for maintaining adequate vitamin B12 levels, which are necessary for various bodily functions, including the production of red blood cells and the maintenance of the nervous system. Various medical conditions can affect the production of intrinsic factor, including autoimmune disorders that specifically target either intrinsic factor itself or the parietal cells that produce it. Other factors that may impair intrinsic factor production include atrophic gastritis, which damages the parietal cells, bariatric surgery that alters the stomach's structure, gastric tumors that may interfere with normal cell function, and congenital deficiencies caused by mutations in the GIF gene located on chromosome 11. A deficiency in intrinsic factor can lead to significant health issues, such as megaloblastic anemia, autoimmune pernicious anemia, and in cases of congenital deficiency, it may result in failure to thrive and neurological abnormalities. To assess the levels of intrinsic factor, a gastric aspirate may be tested using the charcoal method of immunoassay, which is a specific laboratory technique employed to detect and quantify the presence of intrinsic factor in the sample.