Epidermolysis bullosa acquisita is a chronic autoimmune disorder characterized by subepidermal blisters in the skin and mucous membranes and is mostly reported in adults.
Presentation
Although epidermolysis bullosa acquisita (EBA) can be seen at any age, it has an increased prevalence in adulthood. The presentation of EBA is varied, with five clinical patterns being described so far.
Patients with classical EBA show skin fragility and the formation of non-inflammatory tense bullae that are prone to rupture. These lesions develop more on sites subject to minor trauma, such as the back of the hands, knuckles, elbows, knees and feet. The blisters heal with scarring and the formation of small inclusion cysts in the epidermis, termed milia [1]. Mucosal involvement is noted.
Bullous pemphigoid-like EBA shares clinical features with bullous pemphigoid, with patients presenting with lesions that are widespread, occurring in the trunk, extremities and skin folds [2]. Being surrounded by inflamed skin, the blisters are usually tense, with pruritus a common finding. Milia and scarring are not prominent.
A mucous membrane variant, termed cicatricial pemphigoid-like EBA, manifests with erosions and scarring on mucosal surfaces such as the mouth, conjunctiva, upper esophagus, vagina and anus [3]. The features of classical EBA may be absent in such cases.
The Brunsting-Perry pemphigoid-like variant of EBA occurs with bullae primarily on the head and neck region. Lesions often tend to heal with scarring with the involvement of mucosal lining being uncommon [4].
Immunoglobulin (Ig) A bullous dermatosis-like EBA appears with an annular arrangement of bullae seen characteristically in linear IgA bullous dermatosis [5]. Mucous membranes can be affected.
EBA rarely shows up in children, with the mucous membranes being more frequently involved.
EBA can occur concurrently with a variety of systemic diseases, such as systemic lupus erythematosus (SLE), inflammatory bowel disease (IBD), rheumatoid arthritis, amyloidosis, thyroiditis, leukemia, diabetes etc.
Workup
EBA shares many clinical and immune-pathological features with other subepithelial blistering disorders and so its identification may hence be challenging. A thorough patient history and full skin examination help to narrow the differential diagnosis. Additional tests must be performed to confirm the disease.
The histopathological findings vary with the clinical subtype, with early lesions showing blister formation along the dermal-epithelial junction (DEJ) with adjacent papillary edema [6]. The intensity of inflammation may vary with the type of lesion encountered.
Direct immunofluorescence shows the deposition of immunoglobulins in almost all cases. Classical EBA presents with the deposition of IgG and complement along the DEJ. Some subtypes may also showcase the presence of IgA, IgM, factor B and properdin [7].
Indirect immunofluorescence using the salt-split skin technique may demonstrate the presence of antibody binding to the dermal side of the basement membrane. This test may help to differentiate EBA from other autoimmune disorders causing subepithelial blister formation [8].
Additional studies may be done to support a diagnosis of EBA in the setting of a negative immunofluorescence report. These include direct and indirect immunoelectron microscopy, enzyme-linked immunosorbent assay (ELISA), immunoblotting, immunoprecipitation and collagen immunomapping techniques [7] [9].
Treatment
Treatment for AEB focuses on managing symptoms and preventing complications. This may include wound care to protect and heal blisters, pain management, and the use of topical or systemic medications to reduce inflammation and prevent infection. In some cases, addressing an underlying condition, such as an autoimmune disorder, can help alleviate symptoms. Patients may also benefit from lifestyle modifications to minimize skin trauma.
Prognosis
The prognosis for AEB varies depending on the underlying cause and the severity of the condition. While some patients may experience significant improvement with treatment, others may have persistent or recurrent symptoms. Early diagnosis and appropriate management are crucial for improving outcomes and quality of life.
Etiology
The exact cause of AEB is not fully understood, but it is believed to be associated with autoimmune processes or external factors such as medications, infections, or other medical conditions. In autoimmune-related cases, the body's immune system mistakenly attacks proteins that help hold skin layers together, leading to blister formation.
Epidemiology
AEB is a rare condition, and its exact prevalence is not well-documented. It can affect individuals of any age, but it is more commonly diagnosed in adults. There is no known gender or ethnic predilection, and cases have been reported worldwide.
Pathophysiology
In AEB, the structural integrity of the skin is compromised, leading to blister formation. This can occur due to the presence of autoantibodies that target proteins responsible for skin cohesion. The resulting separation of skin layers causes fluid-filled blisters to form, which can rupture and lead to painful erosions.
Prevention
Preventing AEB can be challenging due to its varied causes. However, managing underlying conditions, avoiding known triggers, and protecting the skin from trauma can help reduce the risk of blister formation. Regular follow-up with healthcare providers is essential for monitoring and managing the condition effectively.
Summary
Acquired Epidermolysis Bullosa is a rare, non-genetic blistering disorder that typically presents in adulthood. It is characterized by fragile skin and mucous membranes that blister easily. Diagnosis involves clinical evaluation and laboratory tests, while treatment focuses on symptom management and addressing underlying causes. The prognosis varies, and prevention strategies are limited but can include minimizing skin trauma and managing associated conditions.
References
- Harman KE, Whittam LR, Wakelin SH, et al. Severe, refractory epidermolysis bullosa acquisita complicated by an oesophageal stricture responding to intravenous immune globulin. Br J Dermatol. 1998;139:1126–1127.
- Gammon WR, Briggaman RA, Woodley DT, et al. Epidermolysis bullosa acquisita – a pemphigoid like disease. J Am Acad Dermatol. 1984:820–832.
- Dahl MG. Epidermolysis bullosa acquisita – a sign of cicatricial pemphigoid? Br J Dermatol. 1979;101:475–483.
- Kurzhals G, Stolz W, Meurer M, et al. Acquired epidermolysis bullosa with the clinical feature of Brunsting-Perry cicatricial bullous pemphigoid. Arch Dermatol. 1991;127:391–395.
- Callot-Mellot C, Bodemer C, Caux F, et al. Epidermolysis bullosa aquisita in childhood. Arch of Dermatol. 1997;133:1122–1126.
- Elston DM, Stratman EJ, Miller SJ. Skin biopsy: Biopsy issues in specific diseases. J Am Acad Dermatol. 2016 Jan;74 (1):1-16; quiz 17-8.
- Lehman JS, Camilleri MJ, Gibson LE. Epidermolysis bullosa acquisita: concise review and practical considerations. Int J Dermatol. 2009 Mar;48(3):227-35; quiz 235-6
- Woodley D, Remington J, Chen M. Autoimmunity to type VII Collagen: Epidermolysis Bullosa Acquisita. Clin Rev Allerg Immunol. 2007;33:78–84.
- Vodegel RM, de Jong MC, Pas HH, Jonkman MF. IgA-mediated epidermolysis bullosa acquisita: Two cases and review of the literature. J Am Acad Dermatol. 2002;6:919–25.