Junctional epidermolysis bullosa

Author: Jane Widdowson et al, DEBRA New Zealand, February 2016.

Synonyms:

Junctional EB, Junctional epidermolysis bullosa Herlitz type, Junctional epidermolysis bullosa non-Herlitz type, Generalised severe junctional epidermolysis bullosa, Generalised intermediate junctional epidermolysis bullosa

Categories:

Genetic disorder

Subcategories:

Diagnosis of junctional epidermolysis bullosa

ICD-10:

Q81.1

ICD-11:

EC31

SNOMED CT:

399971009, 724225008, 400140006

What is epidermolysis bullosa?

Epidermolysis bullosa (EB) is a group of inherited diseases that are characterised by blistering lesions on the skin and mucous membranes. These may occur anywhere on the body but most commonly appear at sites of friction and minor trauma such as the feet and hands. In some subtypes, blisters may also occur on internal organs, such as the oesophagus, stomach and respiratory tract, without any apparent friction.

What is junctional epidermolysis bullosa?

In junctional epidermolysis bullosa simplex (JEB), the site of blister formation within skin is the lamina lucida within the basement membrane zone. It causes generalised blistering of the skin and internal mucous membranes of varying severity.

Who gets junctional epidermolysis bullosa?

JEB is a rare inherited disease . Most subtypes of JEB are of dominant inheritance. This means they are passed down from an affected parent to half of his or her children. JEB occurs equally in males and females.

What are the clinical features of junctional epidermolysis bullosa?

JEB Subtypes	Features
Generalised severe JEB Previously known as Herlitz JEB	Generalised and most severe form of JEB where blisters appear all over the body and often involve mucous membranes and internal organs May only present at birth with small single blister but becoming more widespread soon after Hoarse cry or cough is indicative of internal organ involvement Complications such as infection, malnutrition and dehydration usually lead to early death in infancy Most cases are lethal within the first 12–24 months of life
Generalised intermediate JEB Previously known as non-Herlitz JEB	Generalised blistering and mucosal involvement present at birth or soon after Scalp, nails and teeth more involved Complications such as infection, malnutrition and dehydration may cause death in infancy but those who survive clinically improve with increasing age

JEB Subtypes

Features

Generalised severe JEB
Previously known as Herlitz JEB

Generalised and most severe form of JEB where blisters appear all over the body and often involve mucous membranes and internal organs
May only present at birth with small single blister but becoming more widespread soon after
Hoarse cry or cough is indicative of internal organ involvement
Complications such as infection, malnutrition and dehydration usually lead to early death in infancy
Most cases are lethal within the first 12–24 months of life

Generalised intermediate JEB
Previously known as non-Herlitz JEB

Generalised blistering and mucosal involvement present at birth or soon after
Scalp, nails and teeth more involved
Complications such as infection, malnutrition and dehydration may cause death in infancy but those who survive clinically improve with increasing age

How is junctional epidermolysis bullosa diagnosed?

In the dominant subtypes of EB, where an informative family tree is known, it is often acceptable for a clinical diagnosis to be made by a specialist dermatologist based on the presenting signs. Diagnostic tests are also available in some countries and include immunofluorescence antigen mapping (IFM) and/or transmission electron microscopy (EM) of a skin biopsy of a newly induced blister.

Mutational analysis (blood testing of genes) is also available in some countries

What is the treatment of junctional epidermolysis bullosa?

See treatment of epidermolysis bullosa – general.

Where available, gel-type and silicone dressings are most suitable for infants with JEB, as they cause low degree of trauma on removal.
Management of respiratory symptoms may include humidified oxygen and medications