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Hi XXXXX,
Thanks for writing in to us.

I have read through your query in detail.

The cause for allergic reaction in your wife might be a medication, any particular food, pollutants in the environment or any substance which comes in contact with her and triggers a reaction. These reactions are antigen antibody reactions and consulting an immunologist might help.

To pinpoint the allergy problem -- and determine the treatment – your doctor will ask questions about your symptoms and habits. You’ll also need various tests.

Diagnosis

Allergy Testing: The Physical Exam
Diagnosing allergies starts with a doctor’s exam. Learn which questions your doctor may ask so you can be prepared.

Food Allergy Testing
Proper testing can make it much easier to live with a food allergy. See a list of the most common food allergies and learn how testing can make your life easier.

Allergy Symptom Diary
If you have a food allergy, you may need to keep a food diary – and remove certain foods from your diet – to determine exactly what you’re allergic to.

Elimination Diet
The elimination diet involves removing specific foods or ingredients from your diet that you and your doctor suspect may be causing your allergy symptoms (common allergy-causing foods include milk, eggs, nuts, wheat, and soy). Your doctor will supervise this diet over a few weeks.

Allergy testing involves having a skin or blood test to find out what substance, or allergen, may trigger an allergic response in a person. Skin tests are usually done because they are rapid, reliable, and generally less expensive than blood tests, but either type of test may be used.

Skin tests
A small amount of a suspected allergen is placed on or below the skin to see if a reaction develops. There are three types of skin tests:

Skin prick test. This test is done by placing a drop of a solution containing a possible allergen on the skin, and a series of scratches or needle pricks allows the solution to enter the skin. If the skin develops a red, raised itchy area (called a wheal), it usually means that the person is allergic to that allergen. This is called a positive reaction.

Intradermal test. During this test, a small amount of the allergen solution is injected into the skin. An intradermal allergy test may be done when a substance does not cause a reaction in the skin prick test but is still suspected as an allergen for that person. The intradermal test is more sensitive than the skin prick test but is more often positive in people who do not have symptoms to that allergen (false-positive test results).

Skin patch test. For a skin patch test, the allergen solution is placed on a pad that is taped to the skin for 24 to 72 hours. This test is used to detect a skin allergy called contact dermatitis.
Blood test



Allergy blood tests look for substances in the blood called antibodies. Blood tests are not as sensitive as skin tests but are often used for people who are not able to have skin tests.

The most common type of blood test used is the enzyme-linked immunosorbent assay (ELISA, EIA). It measures the blood level of a type of antibody (called immunoglobulin E, or IgE) that the body may make in response to certain allergens. IgE levels are often higher in people who have allergies or asthma.

Other lab testing methods, such as radioallergosorbent testing (RAST) or an immunoassay capture test (ImmunoCAP, UniCAP, or Pharmacia CAP), may be used to provide more information.

I hope this helps.
Do write back in case of doubts.

Dr.A.Rao Kavoor

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