Diagnosis and testing of Fabry disease
The number of people living with Classic Fabry disease is estimated to be around 1 in every 40,000–170,000, but may be much higher, since many patients aren’t diagnosed until later in life.1
Getting a Fabry disease diagnosis can be a long and frustrating process involving many doctors or specialists before the correct diagnosis is made. This process can be especially difficult for women and children, since doctors may miss clues or mistake their symptoms for other conditions.1,2
It’s important to know when to get tested for Fabry disease, because a diagnosis can make sense of unexplained symptoms and empower you to advocate for the care you need. Whether or not you are affected, learning more can bring peace of mind. An accurate diagnosis can make a meaningful difference in your long-term health.1
Why is early Fabry disease diagnosis important?
When Fabry disease is not known in the family, it can sometimes take as long as 15 years to get an accurate diagnosis. Living without a diagnosis to explain symptoms can lead to years of suffering and frustration. It is important to get a diagnosis as early as possible, because Fabry disease gets worse over time and can cause serious problems with the kidneys, heart, and brain. Serious health problems from Fabry disease often begin between ages 30 and 50 and may appear earlier in men (biological males) than in women (biological females).1-3
If doctors diagnose signs of Fabry disease early on, treatment can start sooner. Early treatment can help slow disease progression and can delay more serious or life-threatening problems.4
Fabry disease is a life-long condition, so getting a diagnosis early on will give patients useful information about what they can expect in the future. Because Fabry disease is passed down in families, getting diagnosed early gives you the chance to talk with relatives who may need testing and learn whether the condition could affect future generations.5
The importance of early detectionGetting diagnosed early and managing appropriately could make a big impact on outcomes for people with Fabry disease and their families.4 The earlier you confirm a diagnosis of Fabry disease, the sooner you can talk with your doctor about options for treatment and management. |
Misdiagnosis is common in Fabry disease
Fabry disease is rare, and symptoms can be confused with other more common illnesses, like lupus or multiple sclerosis. For this reason, it’s not unusual for people with Fabry disease to be mistakenly diagnosed with another illness, or misdiagnosed, especially early on. Women and young children are more likely to get misdiagnosed, because Fabry disease is not as easy to spot in these groups.5
Symptoms can vary widely from person to person, which means doctors may sometimes miss the signs that lead to a Fabry disease diagnosis.2 That's why anyone with a family history of Fabry disease can benefit from creating a medical family tree—to help decide whether testing might be right for them. For help getting a medical family tree, contact your patient education liaison (PEL).
Fabry disease misdiagnosis in children
In children, Fabry disease may cause pain and burning in the hands and feet, recurrent fever, gastrointestinal problems, and overheating with exercise. It is common for Fabry disease symptoms like these to initially be mistaken for other disorders, including juvenile arthritis (a form of arthritis in children), growing pains, or rheumatic fever (a disease that can happen after a bad sore throat and may cause joint or heart problems).6,7
Fabry disease symptoms are caused by the build-up of a fatty substance called GL-3 in the body, which can affect multiple cell types in various organs and blood vessels throughout the body. Children might have to miss gym class at school because of pain, feeling too hot during exercise, or having to go to the bathroom a lot. Children with Fabry disease who are not diagnosed might have their symptoms minimized, dismissed, or attributed to uncooperative behavior rather than recognized as experiencing genuine medical concerns.2,8
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Why testing can be important
Symptoms of Fabry disease can be easy to miss, which can delay diagnosis. Fortunately, testing is usually straightforward and often only requires a blood or saliva sample.9,10
If you or someone in your family has symptoms of Fabry disease, talk to your doctor about your concerns, so they can help you decide whether you should be tested as a next step. Since Fabry disease is passed down in families, your family’s medical history can also be an important clue for both you and your doctor.
How is Fabry disease diagnosed?
Fabry disease is typically diagnosed using a simple blood or saliva sample that tests for alpha-GAL enzyme levels or alterations in the GLA gene.9
Enzyme testing for males
For males, Fabry disease testing uses a blood sample to measure the level of the alpha-GAL enzyme. If the enzyme test (also called an “assay”) shows low alpha-GAL activity, then the person has Fabry disease.9,10
Genetic testing for females
For females, a different type of test is needed because blood levels of the alpha-GAL enzyme could be low or close to normal. Instead, a DNA test is done using a blood, saliva, or cheek swab sample. If the gene that makes the alpha-GAL enzyme (the GLA gene) contains certain changes or errors, then the person has Fabry disease.9,10
Which doctors help diagnose Fabry disease?
Getting a Fabry disease diagnosis may involve more than one type of doctor, since patients are often referred to specialists to help manage their symptoms.11
Doctors that diagnose Fabry disease may include:
- Cardiologist: Heart
- Dermatologist: Skin
- Geneticist: Genes
- Gastroenterologist: Digestive organs
- Nephrologist: Kidneys
- Optometrist: Eyes
- Primary care physician: General care
If you suspect you, someone in your family, or someone you care for may have Fabry disease, talk to your doctor about testing.
Seeing the signs of Fabry diseaseFor many people with Fabry disease, their eye doctor was the first to notice signs of the condition, because it can cause a special whorl pattern on the cornea called “corneal whorling” that only shows up during an eye exam.2 |
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Learn about Fabry disease testing and diagnosis
If you want to connect with our team to get more information about testing for Fabry disease, a Case Manager is available to speak with you Monday through Friday, 8AM-6PM ET.
Call 1-800-745-4447 (for English, press 3; para español, oprima 7) or email info@CareConnectPSS.com.
References
1 Morales M, Cruz J, Brignani E, Acuna L, Lazaro E, Soria C. Quality of life and unmet needs in patients with fabry disease: a qualitative study. Orphanet J Rare Dis. Oct 18 2024;19(1):389. doi:10.1186/s13023-024-03412-6
2 Germain DP. Fabry disease. Orphanet J Rare Dis. Nov 22 2010;5:30. doi:10.1186/1750-1172-5-30
3 Mehta A, Hughes DA. Fabry Disease. GeneReviews® [Internet]. 1993-2025.
4 van der Veen SJ, Korver S, Hirsch A, et al. Early start of enzyme replacement therapy in pediatric male patients with classical Fabry disease is associated with attenuated disease progression. Mol Genet Metab. Feb 2022;135(2):163-169. doi:10.1016/j.ymgme.2021.12.004
5 Laney DA, Fernhoff PM. Diagnosis of Fabry disease via analysis of family history. J Genet Couns. Feb 2008;17(1):79-83. doi:10.1007/s10897-007-9128-x
6 Ellaway C. Paediatric Fabry disease. Transl Pediatr. Jan 2016;5(1):37-42. doi:10.3978/j.issn.2224-4336.2015.12.02
7 Ezgu F, Alpsoy E, Bicik Bahcebasi Z, et al. Expert opinion on the recognition, diagnosis and management of children and adults with Fabry disease: a multidisciplinary Turkey perspective. Orphanet J Rare Dis. Mar 2 2022;17(1):90. doi:10.1186/s13023-022-02215-x
8 Bugescu N, Naylor PE, Hudson K, Aoki CD, Cordova MJ, Packman W. The Psychosocial Impact of Fabry Disease on Pediatric Patients. J Pediatr Genet. Sep 2016;5(3):141-9. doi:10.1055/s-0036-1584357
9 Genetic Testing in the US. National Fabry Disease Foundation. Accessed August 19, 2025. https://www.fabrydisease.org/images/ReferencePDFs/Genetic-Testing-10.pdf
10 Germain DP, Altarescu G, Barriales-Villa R, et al. An expert consensus on practical clinical recommendations and guidance for patients with classic Fabry disease. Mol Genet Metab. Sep-Oct 2022;137(1-2):49-61. doi:10.1016/j.ymgme.2022.07.010
11 Fabry Disease: Perspectives from 5 Years of FOS. Oxford PharmaGenesis; 2006.
Sanofi does not provide medical advice, diagnosis, or treatment. The health information contained herein is provided for general educational purposes only. Your healthcare professional is the best source of information regarding your health. Please consult your healthcare professional if you have any questions about your health or treatment.
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