Asthma Methacholine Challenge
What is a Methacholine Challenge test?
In this test, your physician is testing to see how reactive your lungs are to irritants in the environment. A breathing test is administered following each dose of methacholine to see the degree of the constriction of the airways.
Why is a Methacholine Challenge test used?
Your physician will review any medications that you are on and may have you end use to prevent interference with the testing. You may also be asked to not consume any products with caffeine before the test. To begin, you will go through a spirometry test to see where your breathing is at. Then you will receive a dose of methacholine. You will then complete the test again.
Methacholine Challenge Test Results
The results are considered positive if the methacholine causes a 20% or greater decrease in your breathing, which means that your airways are reactive. In the case of a negative test, this means that the diagnosis of asthma is unlikely.
Methacholine Challenge Test Risks
Rarely are there serious risks with the test. Once you begin feeling slight symptoms, your physician will end the testing. You may feel dizzy from the deep breathing. There are rare instances when severe reactions may occur, so your physician will watch you through the whole test.
Asthma Imaging Tests
Overview of Asthma Imaging Tests
Imaging tests are not necessarily used to diagnosis asthma, but are used to show your physician what is happening in your chest. Through imaging, your physician can see a whole picture of your lungs, heart, and bones. This will help ensure the proper diagnosis in case there are other medical conditions happening that may cause asthma symptoms.
While chest radiography may not be a true asthma test, it is helpful in ensuring that there is nothing else causing the asthma symptoms. Through this test, your physician can see the heart, lungs, and bones and can see if it is really asthma causing these symptoms.
A computed tomography scan, or CT scan, shows your physician a more detailed picture of your chest than an x-ray. During this test, there are many images taken of your chest that are put together to create one large picture.
Magnetic Resonance Imaging
Magnetic resonance imaging, or an MRI, is used to properly diagnose you. This type of imaging does not have radiation. This will show your physician a detailed picture of your body and the physician will be able to see any diseases or injuries that have occurred.
Asthma Sputum Eosinophil
Overview of Sputum Eosinophil
There are three types of testing for eosinophilic asthma. These tests will show the level of eosinophil, which will prove whether or not you have eosinophilic asthma. This type of asthma requires a different type of treatment.
Sputum Induction Test
For this type of testing, your physician will ask that you cough up a mucus sample. This sample is sent away for testing. This test is extremely accurate, however, it takes a while to receive the results and not all labs can complete this test.
Asthma Blood Test
Overview of Asthma Blood Test
This test requires a blood sample be taken to measure the eosinophils in the blood. Almost any lab can do this and it is much cheaper. The one problem with this is that while it does measure the level of eosinophils in the blood, it does not show if you have asthma.