All About Asthma and Lab Testing

Asthma is a chronic condition that affects the lungs. The bronchi in the lungs constrict due to this condition. Bronchi are the tubes that carry air to the lungs. Air is transported from/to smaller branches of airways known as bronchioles in the bronchi. The walls of the bronchi become inflamed and swell when one has asthma. This narrowing of the airways makes it difficult to breathe – which can lead to breathlessness, coughing, and wheezing. Acute asthma attacks will complicate the situation by constricting the bronchi muscles and producing more mucus. 

When one has acute asthma, the diameter of the bronchi can decrease to the point where very little air can travel in and out. The patient may cough and wheeze and feel a tightness in the chest when this happens. The actual cause of asthma isn’t clear. But the condition can occur at any time and worsen at night or in the morning hours. Severe asthma attacks need immediate medical attention as it can be life-threatening. 

More than 25 million people in the United States have asthma. Over 7 million of the affected people are kids – which makes asthma one of the most common chronic diseases in children. Asthma will affect more boys than girls before puberty. But after puberty, the condition affects more girls. Asthma is prevalent in urban areas compared to rural areas. Asthma is more common among people of African and Hispanic descent than in Caucasians. The condition isn’t curable or preventable at the moment. But you can control the condition to live an active and relatively normal life. 

Causes

Although the exact cause of asthma is unknown, medical experts believe it’s a complex interaction of many factors. The cell lining of the bronchi seems to release inflammatory molecules in response to various triggers in the environment. The triggers or stimulators for asthma attacks can be quite different for each patient. Here are some of these triggers:  

  • Allergens such as pollen, animal hair & cells, dust/spores, food 
  • Stress or strong emotional responses 
  • Exercise 
  • Occupational allergens such as hairdressing products, cleaning agents, smoke, epoxy glues, and chemicals 
  • Medicines such as aspirin and beta-blockers 
  • Exposure to cold air 

Symptoms of The Condition 

The condition is separated into four categories depending on the severity and frequency of the symptoms. The categories are mild intermittent, mild persistent, moderate persistent, and severe persistent. The first category of patients has only occasional episodes and no symptoms during other times. Patients who suffer from severe persistent asthma may need medications several times a day to control the condition. 

Other lung conditions may have similar symptoms to asthma. Emphysema is such a condition that could co-exist or exacerbate asthma. GERD or gastroesophageal reflux disease can also trigger or worsen the asthma condition in some patients.  

Tests 

The main goal of initial asthma testing is to diagnose the severity of the condition. Testing is important to separate asthma from other conditions that have similar symptoms. Continued testing will help monitor lung function and asthma control. They will help evaluate and resolve the attack as well as identify and address complications or side effects of the condition. 

Laboratory Tests 

Laboratory testing will rule out conditions that have similar symptoms to asthma. It also helps identify allergens, allergies, and any complications that may occur as a result of the condition. If a person has severe asthma, testing may be ordered to monitor oxygen levels, organ function, and the body’s acid-base balance. Some of the tests include: 

  • Blood testing for sensitivity to allergens – Blood tests that are specific to the allergens suspected of causing asthma. Some of the allergens include dust mites, pet dander, mold, and mildew. These tests will help determine the triggers of asthma. 
  • Blood gases – A blood sample is collected from an artery to evaluate blood oxygen, pH, and carbon dioxide levels. This test will be ordered when a person is having an attack. 
  • CBC or complete blood count – This test will evaluate the blood cells and provide necessary information on inflammation and infection. 
  • CMP or comprehensive metabolic panel – This test will help evaluate organ function. 
  • Theophylline – If a patient is suffering from asthma is taking this drug; the healthcare provider will evaluate the results of general tests, family history, medical history, and risk factors for other diseases. Based on the findings, other laboratory tests are performed, such as: 
  • Tests that rule our cystic fibrosis – Sweat test or trypsin/chymotrypsin 
  • AFB testing – Diagnosing nontuberculous mycobacteria (NTM) or tuberculosis 
  • Sputum culture – Diagnosing lung infections 
  • Lung biopsy – Diagnose lung cancer 
  • Sputum cytology – This test is ordered to evaluate various cells found in the lungs, such as neutrophils and eosinophils – which are two types of white blood cells. These cells are increased with inflammation in people who are suffering from asthma.