Depending on the individual patient, we may use some of the following tests to diagnose allergies or asthma. Click on the tests for more information.
Skin Testing
Tests for:
Airborne, insect and food allergens by measuring your level of allergic antibodies (IgE) to these allergens.
How it works:
Using a tiny plastic device, we apply small amounts of solutions that contain different allergens to the skin with a small scratch (or skin prick). A raised area on the skin indicates a positive reaction. A positive reaction does not always mean that you are allergic to that allergen, since other factors may play a role.
If we suspect an allergen that does not show up on prick tests, we usually repeat the same allergen using a very small needle. We inject a small amount of allergen into the first layer of skin forming a small bubble or bleb. If positive, it will look and feel like a small mosquito bite (same as the prick test.)
What to expect:
We usually have results within 15 to 20 minutes. The testing area may get itchy, but this usually doesn't last very long.
Important notes:
You should refrain from using antihistamines at least 5 to 7 days prior to your testing visit. Skin testing is usually not performed on those who have had a severe life-threatening reaction to an allergen or those with severe eczema or hives.
Patch Testing
Tests for:
Chemicals causing a delayed type of reaction, as in contact dermatitis. Contact dermatitis is not a true allergy involving allergic antibodies. Rather, it results from white blood cells (T-cells) entering the skin in response to an irritant.
How it works:
We place a safe, chemical patch test panel on your back using paper tape. The patch remains on the skin for two days, and we then remove it for an initial reading. The tests are read again three to four days after the initial placement.
What to expect:
To prepare for the test, a patient should have clean skin and should have recently bathed. The skin should not be cleaned with rubbing alcohol, which may irritate the skin. The tape cannot get wet while placed on the back, so bathing is limited during this time. Vigorous sports should be avoided, because if the adhesive tapes peel off, the process will have to be repeated. A test is considered positive if bumps, blisters or swelling develop at the individual sites.
Important notes:
For one month prior to patch testing, you should not take any oral steroids or systemic immunosuppressants. Topical steroids cannot be used at the site of patch testing for one week prior to testing. Antihistamines, inhaled steroids and leukotriene receptor antagonists can be continued as usual.
Spirometry
Tests for:
The amount of air in your lungs and how quickly you can move air out of your lungs. This test can help diagnose asthma, measure the severity of asthma and monitor how well treatment is working.
How it works:
You breathe into a mouthpiece attached to a recording device (spirometer), and the results are printed out on a chart called a spirogram.
What to expect:
This is a simple, non-invasive test, and results are available immediately. Depending on your results, you may be given a bronchodilator treatment, such as albuterol or levoalbuterol, while in the office.
Laboratory Testing
Tests for:
Food allergies and environmental allergies by detecting allergic antibodies (IgE) to allergens (ImmunoCAP test); immune system deficiencies in patients with recurrent infections; evaluation of chronic hives; and other issues.
How it works:
Blood tests are usually ordered when a patient cannot undergo a skin test because of antihistamine use or various skin diseases, when a patient has an immune system disorder or when a patient has chronic hives. Blood tests are performed at outside labs.
What to expect:
Depending on the test ordered, results are usually available within a few days to weeks.
Diagnostic Imaging
Tests for:
Lung diseases such as asthma, chronic obstructive pulmonary disease (COPD) and pneumonia; chronic sinus problems such as chronic sinusitis, nasal polyps or other sinus disease.
How it works:
X-rays or CT scans are taken of the chest or sinuses. Tests are performed at an area hospital or radiology center.
What to expect:
A report will usually be sent to us soon after the imaging test is performed. In some cases, we may ask that you bring a copy of the X-ray or CT scan to your next visit.
