Asthma is a chronic condition that often occurs during childhood. The symptoms of asthma include frequent coughing that may occur while the child is laying down, running, or laughing. The child may also suffer from shortness of breath, tightness in the chest, and a wheezing sound that can be heard when inhaling and exhaling. When these symptoms first begin, it is important to have diagnostic tests done to find out if the child suffers from asthma. These are some of the common tests that are performed to diagnose asthma in children.

Medical History And Chest X-rays 

Asthma is sometimes a condition that more than one person in the same family suffers from. If the child who has the symptoms has a close relative who was diagnosed with asthma, there is a chance the child could have the same condition. The physician will look at the medical history of the patient to see if there is a possibility that he may have inherited asthma.

A chest X-ray is also performed to rule out other problems that may be causing the symptoms. Conditions such as an upper respiratory infection, bronchitis, and pneumonia will show up on a chest X-ray. If these conditions are not evident, there is a likelihood that the patient may be suffering from asthma.

Spirometer Tests 

Another diagnostic test for asthma that is commonly performed on children is a spirometer test. In this test, the child must take deep breaths and then force each breath into a tube that is connected to a machine known as a spirometer. The machine measures and records the volume of the breath that is exhaled and the speed in which the breath is exhaled.

If the measurements are below the normal rate, the patient may be asked to repeat the same test after using an inhaler to open up the air passages. If there is a noticeable improvement in the breath measurements after using the inhaler, this is an indication that the child may have asthma.

Methacholine Challenge Tests 

If the spirometer test is just slightly below normal, the physician may also perform the methacholine challenge test. In this test the child must first inhale a drug that narrows the airways of those who have asthma. If the asthmatic symptoms occur after using this drug, this increases the likelihood that the child has asthma. 

Exhaled Nitric Acid Test 

The physician may also have the patient exhale into a tube that is connected to a machine that measures the amount of nitric acid that is in the breath. Those who have extremely high levels of nitric acid often have inflamed air passages, which is another symptom of asthma.

Once asthma is diagnosed, it is often necessary for the child to be tested by an allergist, such as Diane L. Ozog, MD, SC. The allergist can run a variety of different allergy tests to determine if the asthmatic symptoms are caused by something the patient is allergic to.