Asthma Experts: Asthma Frequently Misdiagnosed

"Cough... wheeze!?  err... um... Here's an inhaler!"

The following was originally published at healthcentral.com/asthma on 11/8/13.

Asthma Misdiagnosis: Why is it so common?

Could you imagine being diagnosed with asthma, being treated as though you have asthma, only to learn many years later that you have something else?

This apparently is the case for millions of “asthmatics” around the world, according to Dr. Tod Olin, pediatrician at National Jewish Health, one of the leading asthma research centers in all the world.

Believe it or not, there are many diseases whose symptoms resemble asthma, so it really shouldn’t surprise you too much that these might be misdiagnosed as asthma. Consider some of the following examples:

• Upper airway obstruction
• Heart failure 
• Vocal cord dysfunction
• Bronchopulmonary dysplasia
• Cystic Fibrosis (some treatments are similar to asthma)
• Enlarged lymph nodes
• Cancer (lesions in upper and lower airway)
• Viral infections
• Sinus infections
• Chronic Obstructive Pulmonary Disease (emhysema or chronic bronchitis)
• Bronchiolitis
• Pulmonary Embolism
• Recurrent cough not due to asthma
• Transient wheeze not due to asthma
• Acid reflux
• Use of medicines such as beta blockers

It’s interesting to note here that in 400 B.C., when asthma was first introduced to the medical community by Dr. Hippocrates, all of the above diseases were lumped under the umbrella term asthma. This was because, given the lack of anatomical knowledge at the time, anything that caused a wheeze or shortness of breath was diagnosed as asthma.

By the turn of the 19th century there was so much better wisdom about asthma that a Dr. Chevalier Jackson coined the phrase, “All that wheezes is not asthma." By saying this he was trying to convince his fellow physicians that there are many diseases that cause a wheeze, and the treatment for them is completely unique from the treatment for asthma.

In other words, just because someone is short of breath and wheezes does not mean Albuterol and inhaled corticosteroids is the treatment.

So, in this way, as better wisdom has been obtained, all the above medical conditions have been gradually extracted out from under the umbrella term asthma. They have all become disease entities of their own, with their own treatment.

But sometimes, however, as Dr. Olin has noted, even with all the wisdom available to today’s physicians, some doctors still get confused. This is not to say anything bad about these doctors, because making a differential diagnosis can often be very challenging. Even the world's best doctors sometimes misdiagnose their patients.

This was noted recently by Dr. Olin, who said there are many people misdiagnosed with asthma, and the treatment is not working. He was recently quoted by medicalxpress.com as saying:

“It’s very logical for general practitioners to assume most breathing problems are asthma, especially in children. But there are a lot of breathing problems out there, and for children who are failing therapy, we need to think about those other diagnosis.

“In reality, there are many conditions that can mimic the symptoms of asthma, and we need to make sure we have the correct diagnosis before deciding on a course of treatment.”

He said many such asthmatics are referred to him, and among the first things he does is perform a variety of tests to rule out these other diseases. This is a process called differential diagnosis. Some of the following are tests he might perform:

• Physical assessment is the simplest method of diagnosing diseases
• Lab results can help physicians diagnose various diseases
• Review of patient’s history can sometimes make diagnosis easier
• Pulmonary function test can diagnose a variety of medical conditions
• Allergy testing can diagnose allergies
• Bronchoprovocation is a lung test that can prove you do or don’t have asthma
• pH Probe test may diagnose acid reflux
• A sweat test may rule out cystic fibrosis
• A barium swallow under fluroscopy may rule out mediastinum or cardiovascular abnormalities
• An electrocardiogram (EKG) may rule out heart disease
• A high resolution CT scan may show cancer
• A simple x-ray may may rule out upper airway obstruction
• A CT and lab tests may rule out sinusitis

So, as you can see, there are a whole array of tests that a doctor may perform to either rule in or rule out asthma. I remember when I was admitted to National Jewish Hospital in 1985 there was an initial two-week period where I spent nearly every day undergoing these tests and procedures. Of course the end result for me was that I really did have asthma.

But could you imagine finding out that you did not have asthma when you thought you did? It would mean that you were being treated for the wrong disease. Once this revelation is made, however,your doctor may simply make a few changes in your treatment regime, and your “asthma” may go away.

To learn more about how to diagnose asthma, you can read my post “Is it Asthma? Here’s how to find out.”