Diagnosis and Genetic Testing for hATTR Amyloidosis

A tissue biopsy is used to diagnose hATTR amyloidosis

Medically reviewed by Anita C. Chandrasekaran, MD

Getting a diagnosis for hereditary transthyretin (hATTR) amyloidosis is a multistep process. Amyloidosis is a rare disease that causes proteins to build up in the body, forming amyloid deposits. This leads to symptoms including heart disease, neuropathy (nerve damage that can cause numbness, pain, and/or weakness), and organ failure.

Before you can get a diagnosis, healthcare providers must recognize your symptoms, perform a biopsy to confirm the presence of amyloid deposits, and then conduct DNA testing to determine whether your amyloidosis is genetic. Although this process is time-consuming, it’s important since an accurate diagnosis can help you get the most effective treatments.

Continue reading to learn more about hATTR amyloidosis diagnosis, including hATTR amyloidosis symptoms, and how to know if your condition is genetic.

Complications in Diagnosing hATTR Amyloidosis

As its name implies, hereditary transthyretin amyloidosis runs in families. If you have a family history of hATTR amyloidosis that your healthcare provider knows about, it takes about one year to get a diagnosis, on average. But if you don’t have a known family history, diagnosis is much more complicated and can take four to five years.

Having a family history of the disease can help lead clinicians on the right path toward diagnosis, while having no known family history makes the diagnostic process open-ended.

Diagnosis with no known family history is difficult because the symptoms of amyloidosis are wide-ranging. Symptoms can include:

• Discolored skin patches

• Gastrointestinal issues

• Neurological issues like tingling hands or trouble balancing

• Serious organ failure, including cardiac symptoms

Having such broad symptoms can make it hard to identify the root cause.

You might be sent to a cardiologist to address heart disease and a dermatologist to treat skin rashes. If those doctors aren’t communicating, it can take a long time to realize that seemingly unrelated conditions have the same root cause.

Always notify your healthcare provider of all symptoms you’re experiencing, not just the ones that fall within their specialty.

Red Flag Symptoms

So-called red flag symptoms can speed up a hATTR amyloidosis diagnosis. Red flag symptoms include neuropathy (nerve damage that can cause loss of sensation) on one or both sides of the body, paired with at least one of the following symptoms:

• Dry mouth, incontinence, or other signs of autonomic dysfunction

• Fatigue or other symptoms of heart failure

• Severe diarrhea or constipation

• Unexplained weight loss

• Carpal tunnel syndrome in both wrists

• Floaters or other vision changes

Tests to Diagnose hATTR Amyloidosis

To get a hATTR amyloidosis diagnosis, you’ll need a tissue biopsy followed by skin or blood tests. During a biopsy, healthcare providers take a tiny tissue sample from your body. If they think you might have amyloidosis, they analyze this tissue sample in a lab to see if you have protein buildups called amyloid deposits.

Healthcare providers do this by adding a red dye to the tissue sample. If the dye turns green under light, you have amyloid deposits and will be diagnosed with amyloidosis.

After you’ve been diagnosed, healthcare providers need to know what type of amyloidosis you have. While hATTR amyloidosis runs in families, other types of amyloidosis do not. To see if you have the hereditary type of amyloidosis, you’ll need genetic testing. This requires collecting blood or saliva samples and analyzing your DNA, looking for the genetic mutations that can cause amyloidosis.

Once the biopsy and genetic testing prove positive for hATTR amyloidosis, you’ll be given a diagnosis. You may need further tests like this to monitor the progression of the disease.

False Negatives

It’s possible to get a false negative, or a biopsy that doesn’t show protein buildup even if you have amyloidosis. If you or your healthcare provider strongly suspects the condition, ask for genetic testing even if your biopsy was negative.

Imaging and Scans

Once you have a diagnosis, healthcare providers may suggest imaging scans to clearly show how hATTR amyloidosis impacts your body. These scans will look at specific organs, like the heart, impacted by amyloidosis.

Healthcare providers may recommend the following tests:

• Echocardiogram, an ultrasound of the heart

• An eye exam

• Ultrasound, X-rays, or computed tomography (CT) scans to check your kidneys and other organs

Diagnosing hATTR Amyloidosis From Genetic Testing

Sometimes, a close family member like a parent or sibling is diagnosed with hATTR amyloidosis. This raises your risk for the condition significantly, since the disease runs in families. Once a close member is diagnosed with hATTR amyloidosis, it’s recommended that you get genetic testing to see if you have the same gene mutation that causes the disease.

However, genetic testing does not lead to an hATTR amyloidosis diagnosis. If your test shows you have a mutation associated with the disease, you’re at increased risk, but it’s not certain that you’ll develop the condition. After a positive genetic test, your healthcare provider will likely recommend a biopsy and imaging test to look for early symptoms of hATTR amyloidosis.

Empowerment Through Genetic Testing

Getting genetic testing can be scary, especially if your close family member is sick with hATTR amyloidosis. However, getting an early diagnosis helps improve life expectancy. It’s important to get the genetic testing while also working with genetic counselors and mental health providers to process what a positive outcome could mean for you.

Next Steps After Diagnosis

Getting a diagnosis of hATTR amyloidosis can be frightening. It’s important to remember that treatments for hATTR amyloidosis have advanced substantially of late, and researchers are currently studying even more treatment options.

After you are diagnosed, your healthcare providers will want to do a thorough physical workup to look for signs of hATTR amyloidosis in organs, including your heart, skin, and eyes. Part of the therapy for hATTR amyloidosis is in treating the associated symptoms. Getting a clear picture of the impact hATTR amyloidosis is having on your body will inform your treatment plan.

If you’ve been diagnosed with hATTR amyloidosis, you’ll also need to speak with your family. Your siblings, parents, and children are at substantially increased risk of having the condition, too. It’s recommended that they all undergo genetic testing.

Your treatment team can help you talk to your family about this. Some hospitals even offer free genetic testing to family members of people recently diagnosed with hATTR amyloidosis.

Summary

Getting diagnosed with hATTR is complicated, since the disease causes wide-ranging symptoms, from eye issues and heart disease to skin disease and neuropathy. Diagnosis can take up to five years, and may involve misdiagnosis, especially if you don’t have a family history of the disease.

A tissue biopsy is used to show protein buildups that cause amyloidosis, while genetic testing through blood or saliva tests detects the genetic mutations that show you have the hereditary form of the disease. After you’ve been diagnosed, your close relatives including parents, children, and siblings, should undergo genetic testing for hATTR amyloidosis.

Read the original article on Verywell Health.