ELISA food allergy testing, which is also known as the ELISA food intolerance test, is done to find out allergies or intolerance to certain specific food items. It is usually recommended for those who suffer from Irritable Bowel Syndrome (IBS), which is characterized by abdominal pain, cramping, diarrhea, bloating or constipation.
ELISA gets its name from 'enzyme linked immunosorbent assay', because the ELISA food test involves using immunochemical tests with an antigen or antibody (immunologic molecules), and a protein enzyme which helps to catalyze a biochemical reaction.
The ELISA testing for food allergies is basically a blood test. The patient's fingertip is pricked with a small lancet, and a few drops of blood are collected in a small glass vial. While this is usually done in the laboratory, it can also be done at home, and the blood sample can be sent to the lab for analysis.
In the lab, the sample is mixed with certain enzymes or antibodies to test its reaction to an array of different foods, and tested for levels of 'IgG antibodies'. If the levels of IgG antibodies are found to be particularly high, when testing a specific food, it denotes that the patient has an allergy towards that food and is reacting to it.
After testing for reaction levels with various foods, the ELISA report then shows a chart detailing the level of antibodies found in the blood sample. These are usually on a scale of 0 to 130, and are measured as +1 or +2 or +3 and so on.
Since the ELISA food test gives a measurement of the allergy levels to certain foods, it makes treatment much easier. The patients are advised to completely avoid the foods to which they are highly allergic. These are called 'trigger foods' since they trigger the patient's problems. If there are some foods to which they may have a significant reaction, but on a slightly lesser scale, they may be asked to reduce their intake of those foods and not avoid them totally, but eat them only a few times in a week.
This diet is usually followed for about three weeks to monitor if there has been any change or improvement in the patient's condition. Sometimes, a few of the trigger foods are reintroduced to see if they still produce a negative reaction.
Many doctors and patients have found the ELISA test helpful in identifying trigger foods which aggravate the condition, and have therefore used the ELISA-based exclusion diet to reduce symptoms.