Pruritic epidermolysis bullosa

What is pruritic epidermolysis bullosa?

Pruritic epidermolysis bullosa (pruritic EB) is rare and clinically heterogeneous subtype of dystrophic epidermolysis bullosa (EB dystrophic), resulting from a mutation within type VII collagen gene.

Pruritic EB is characterized by intense itching (pruritus) hypertrophic plates in a linear settingIt is usually found in the lower extremities of an affected individual. First described in 1994, fewer than 100 cases have been documented in the literature, and as such little is known about the condition or its treatment.

Who gets pruritic epidermolysis bullosa?

Pruritic EB can present shortly after birth or in early adulthood.

• In neonatesPruritic, EB usually presents as blisters on the peripheral extremities Blisters may continue or temporarily resolve in infancy.
• During adolescence or early adulthood, patients with pruritic EB develop pruritic lichenified plaques that persist long-term. The initial presentation can be delayed until the second or third decade of life.

What Causes Pruritic Epidermolysis Bullosa?

As with other forms of dystrophic EB, the clinical findings of pruritic EB are attributed to mutations in the COL7A1 gene in chromosome 3p21.3, which encodes type VII collagen. Pruritic epidermolysis bullosa case reports reveal many different alterations to this gene, including missense, nonsense, frame shift, and splice site mutations.

Type VII collagen is an important structural component of anchoring skin fibrils in the dermoepidermal union (DEJ). Mutations in the coding gene impede the function of the anchor fibrils and lead to a division in the DEJ below the level of the lamina densa. Clinically, this manifests as traumainduced by blisters, which upon healing leave a scar.

The inheritance is variable; Most cases have been found to be sporadic. Autosomal dominant and autosomal recessive patterns have also been reported.

The characteristic pruritic component of the condition is poorly understood. A raised serum The level of IgE has been found in 7 of 9 patients examined with pruritic epidermolysis bullosa, and in some cases it was found to be more than 3 times the upper limit of normal. However, a personal or family history of atopy was a confounder in three of these patients, so the results are far from conclusive.

It has been suggested that the hypertrophic, lichenified, nodular prurigosimilar to the plaques seen in disease are secondary to chronic scratch

What are the clinical features of pruritic epidermolysis bullosa?

The classic appearances of pruritic EB are intensely itchy, excoriated, lichenified. violaceous papules, nodules and plates. They are generally linear in configuration and most often affect the pre-tibial skin, although they can also be seen on the forearms and trunk. Face, neck and push-ups You are safe. A dystrophy it is seen very commonly and is useful to distinguish from other conditions. Prurigo-type lesions are due to scars and milia are seen within them.

Differential diagnoses include:

• Nodular prurigo
• Chronic lichen simplex
• Hypertrophic lichen planus
• Cutaneous and lichen amyloidosis
• Psychogenic pruritus, e.g compulsive picking disorder
• Dermatitis artifact

How is pruritic epidermolysis bullosa diagnosed?

A presumptive diagnosis of pruritic EB can be made based on clinical findings along with a positive mechanobulous history and clear evidence of inheritance within the family. When the diagnosis is uncertain, the skin biopsies for the light microscopy and to electron microscope they are useful

the histological Features of pruritic EB include hyperkeratosis, acanthosis and interruption of the DEJ, with a prominent dermal and perivascular lymphohistiocytic infiltrate. A subepidermal blister may be seen, although it is seldom clinically evident, as can milia formation.

Electron microscopy can be valuable in confirming the level of division, and should show diminished or absent anchoring fibrils in the dense sub-lamina below the basal cap of the epidermis. Direct immunofluorescence of perilesional skin is negative, but may be useful research to exclude other bullous terms

Genetic the sequence will demonstrate mutations in COL7A1.

What is the treatment for pruritic epidermolysis bullosa?

The most commonly used treatments for pruritic EB are powerful. current steroids under occlusionor intralesional steroids. Other proven treatments include:

• Compression socks
• Oral antihistamines
• Dapsone
• Cyclosporine
• Tacrolimus ointment
• Thalidomide
• Isotretinoin

• UVB phototherapy

• Ketamine-amitriptyline gel.

Success has been mixed and no sustained effects have been reported.

What is the prognosis for patients with pruritic EB?

Little is known about the long-term outcome for patients with pruritic EB. It is chronic and often refractory to treatment. Complications have included lymphedema of the lower extremities, and a single case of a well has been reported differentiated scaly cell carcinoma on the affected skin

Some patients have responded very well to the treatments listed above, but there are no long-term data regarding the sustainability of the induced drugs. remission.