Diagnosing Genetic COPD
It’s not always easy to get a diagnosis of alpha-1 antitrypsin (AAT) deficiency, a rare condition that sometimes leads to serious lung and liver damage. In fact, most people who have this disorder are never diagnosed at all, experts say.
Also called alpha-1, this genetic condition means you don’t have enough of the alpha-1 antitrypsin protein in your bloodstream. When it affects your lungs, it can lead to chronic obstructive pulmonary disease (COPD).
Normally, AAT protects your lungs from being damaged while your immune system fights infection and inflammation. But without enough AAT, substances released during the immune process may harm your lungs and make them more prone to damage from smoking or pollution.
Who Gets AAT Deficiency?
Experts estimate that AAT deficiency affects about 1 in every 3,500 people in the U.S. But only about 10% of them know they have it.
“It’s very underdiagnosed,” says Mike Wells, MD, associate professor of pulmonary, allergy and critical care medicine at the University of Alabama at Birmingham School of Medicine.
About 3% of people with COPD are thought to have undetected alpha-1. You might hear the condition called “genetic COPD” when it’s caused by an AAT deficiency.
Why Is ‘Genetic COPD’ Hard to Diagnose?
Many people with AAT deficiency are healthy and never have symptoms. If you do develop symptoms, they’re most likely to start when you’re between 20 and 50 years old.
Some lung-related symptoms you can have are:
- Shortness of breath
- Chronic cough and bronchitis
- Wheezing
- Repeated colds or pneumonia
- Difficulty exercising
These symptoms can look a lot like those of asthma or smoking-related COPD. Many people are diagnosed with those more common conditions instead. Asthma medications are often helpful for people with AAT deficiency, which can add to the confusion.
Even if you do get diagnosed with AAT deficiency, it can take a long time — an average of 5-8 years after you start having symptoms. You might have to see multiple doctors, too. Research has found that it tends to take longer for women and older people to be diagnosed.
Who Should Be Tested?
While only a doctor can diagnose AAT deficiency, the FDA recently approved a home kit you can use to see if your genes put you at risk for it. The kit, called AlphaID At Home, is available without a prescription. To use it, you collect a saliva sample and send it to a lab to be processed. You should then share the results with your doctor.
To diagnose the condition, your doctor will do a test to detect the condition. Doctors can’t diagnose AAT deficiency just by its symptoms or a medical exam.
Doctors often don’t test their patients for several reasons, says Khalil Diab, MD, a pulmonologist and associate professor at the George Washington School of Medicine and Health Sciences.
It’s a relatively rare disease that doctors might not know much about. Or they might not think testing is helpful. Treatments for AAT deficiency are often expensive and are sometimes seen as ineffective, Diab says.
But certain conditions – especially when they show up in younger people — should prompt testing for AAT deficiency.
“We know alpha-1 can cause COPD and emphysema, but it can also lead to liver injury and cirrhosis, so usually having one of those conditions should clue a provider in to test,” Wells says.
In fact, the American Thoracic Society recommends that doctors test all adults who have COPD, emphysema, severe asthma, or unexplained liver disease for AAT deficiency. The group recommends that siblings of people with the deficiency be tested as well.
How Is AAT Deficiency Diagnosed?
Your regular doctor can test you for the disorder. So can specialists like pulmonologists, allergists, immunologists, and hepatologists, Wells says.
Your doctor might first check the levels of the AAT protein in your blood. But to confirm you have AAT deficiency, they also need to do a genetic test. That’s usually done with a blood test, but your doctor might also swab your nose or the inside of your cheek.
The genetic test will tell you which AAT mutation you have. If you have AAT deficiency, you inherited an abnormal gene from each of your parents.
Different alpha-1 genes carry different risks. So finding out exactly what combination of these genes you have helps your doctor understand your condition and your risk of pulmonary disease. A genetic counselor can help explain your results.
Your doctor might also do imaging tests like X-rays or CT scans to see how much lung damage you may have.
Why Does a Diagnosis Matter?
It’s important to get an AAT deficiency diagnosis because getting treatment early on can slow the development of “genetic COPD.”
Also, if you smoke, knowing you have ATT deficiency gives you a very important reason to quit.
“A lot of people with this deficiency would develop some form of mild breakdown of the lungs when they’re older,” Diab says. “But if somebody is a smoker, they develop it at much younger age than typical COPD patients.”
Since AAT deficiency is genetic, your siblings, parents and children should be tested after you’re diagnosed, Wells says.
Finding out they have the disorder could motivate your family members to stop or avoid smoking so they don’t develop COPD. They’d also know to stay away from secondhand smoke and jobs that involve polluted air.
“It’s important to diagnose it potentially early because it also has implications on the family members of the patients,” Diab says. “I think we should all follow the guidelines and try to get an early diagnosis and then discuss the treatment options with the patient.”
There’s no cure for AAT deficiency, but you can be treated for COPD. There’s also an AAT-specific treatment called augmentation therapy. You get IV injections of ATT protein from blood donors every week. This raises your levels of AAT and slows progression of the disease.
When you’re diagnosed with AAT deficiency, consider seeing a specialist like a pulmonologist if you aren’t doing so already, Wells says.
You should also have yearly liver tests. Since AAT deficiency also affects your liver, you’re at higher risk of developing cirrhosis, or scarring, and liver cancers, Diab says.
