Epidermolysis bullosa diagnosis
Fact-checked by Epidermolysis bullosa (EB) is a group of rare conditions that cause the skin to be fragile and prone to blistering.
In most cases, EB appears at birth or early in childhood, with symptoms that can range from mild to life-threatening, depending on the type and subtype. While it is typically present at birth, EB can be hard to diagnose due to its rarity and wide range of symptoms.
Although there is no cure, an early diagnosis of EB is essential to help people manage symptoms, prevent serious complications, and improve quality of life.
Symptoms that lead to an EB diagnosis
In most cases, EB has a genetic cause and typically develops at birth or in early childhood, with symptoms that may include blistering, pain, itchiness, extreme skin fragility, and wounds that don’t heal. Blisters are often seen in areas exposed to pressure or friction, such as the hands, feet, buttocks, and knees. For some children, symptoms may become more noticeable as they grow older and more physically active.
In people with milder forms of EB, symptoms may not appear until later in life, and the disease may remain undiagnosed until adulthood. In some cases, it may never be recognized, which can lead to misdiagnosis.
Possible symptoms that may lead to a specialist referral for an EB diagnosis include:
- unexplained skin blistering and extreme skin fragility
- itchy, painful skin
- blisters appearing on mucous membranes lining internal parts of the body, such as the mouth, throat, eyes, or gastrointestinal tract
- thickened skin on the palms of the hands and soles of the feet
- small white bumps on the skin (milia)
- thick, misshapen, or missing fingernails and toenails
- scalp blistering and hair loss (alopecia)
Specialists involved in diagnosing EB
A diagnosis of EB may involve a multidisciplinary team of medical professionals, including:
- Pediatrician or primary care provider: Performs an initial evaluation of symptoms, medical history, and family history, and may refer patients to specialists for further testing.
- Dermatologist: Examines the skin, reviews medical and family history, and may request specialized diagnostic tests for EB, including a skin biopsy and genetic testing, if EB is suspected.
- Clinical geneticist: Interprets genetic testing results and communicates them to patients and their families, often in collaboration with a dermatologist.
- Genetic counselor: Helps patients and their families understand how EB is inherited, its long-term outlook, and provides guidance on family planning.
Physical exam and medical history
The first step in diagnosing EB is usually a thorough review of a person’s symptoms, medical history, and family history.
During a physical exam, a doctor will closely examine the skin for signs of EB, such as blistering, milia, nail changes, and wounds. Because different types of EB affect different layers of the skin and vary in severity, the location, frequency, and severity of blisters and other lesions may help point to a specific type.
A doctor will also ask whether any family members have had EB symptoms or been diagnosed with the condition. Understanding family history can help determine the disease’s inheritance pattern and may provide clues about the specific type of EB.
Genetic testing
When EB is suspected, a doctor may recommend genetic testing, which is considered the gold standard for diagnosing different types of EB. For genetic testing, a healthcare provider collects DNA through a blood sample or cheek swab from the person suspected of having EB, and sometimes from their parents. The DNA is then analyzed to look for mutations that cause EB.
There are several DNA sequencing techniques that can be used, including some that focus only on a subset of genes known to be implicated in EB. Some of these genes include:
- KRT5, KRT14, and PLEC, which are associated with EB simplex (EBS)
- LAMA3, LAMB3, LAMC2, COL17A1, ITGA3, and ITGB4, which can be associated with junctional EB (JEB)
- COL7A1, which is implicated in dystrophic EB (DEB)
- FERMT1, which is linked to Kindler syndrome
Identifying a mutation in any of these genes allows healthcare providers to confirm an EB diagnosis and determine the disease’s type and subtype. Because EB severity, prognosis, and potential complications vary by type, this information is important for guiding treatment and long-term care.
Genetic testing may also help doctors understand how EB is inherited, which can inform family planning decisions.
Although genetic testing can provide a definitive diagnosis, it may not be available in all healthcare settings and can be time-consuming and costly.
Skin biopsy and laboratory testing
In addition to genetic testing, a doctor may recommend a skin biopsy followed by laboratory testing to help confirm an EB diagnosis. This may be especially important if genetic testing results are inconclusive or delayed, or when a diagnosis is needed quickly to guide care, such as in newborns.
For a skin biopsy, a doctor typically collects a small skin sample, often from an area not usually exposed to the sun. The sample usually includes both normal-appearing skin and part of a fresh blister. If no fresh blister is present, the skin may be gently rubbed to create one for testing.
The skin sample is then analyzed using a technique called immunofluorescence mapping, or IFM. This method uses specialized antibodies to detect proteins in the skin, helping identify where the skin layers separate and which proteins may be missing or abnormal, which can help determine the EB type and subtype. Another technique, called transmission electron microscopy (TEM), may also be used to examine the skin’s structure in detail and identify changes consistent with EB.
While a skin biopsy can provide faster results and help support an EB diagnosis, it does not identify the underlying genetic cause of the disease. It is also an invasive procedure and may not detect clear abnormalities in people with milder forms of EB.
Next steps after diagnosis
After diagnosis, patients should work with a multidisciplinary team of specialists to develop a treatment plan and manage symptoms. A referral to an EB specialist or care center may also be helpful, especially for people with rarer or more severe forms of the disease.
EB is a lifelong condition, but with proper care, support, and monitoring, many people can manage symptoms, reduce complications, and improve quality of life.
Epidermolysis Bullosa News is strictly a news and information website about the disease. It does not provide medical advice, diagnosis, or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.
