Immunobullous Diseases, Epithelial Antibody Associated

Immunobullous diseases are caused by or associated with specific autoantibodies that bind to epithelium, which affects the barrier function of both skin and mucous membranes, resulting in symptoms such as pain and itchiness.   The autoantibodies are directed to components in skin and mucous membranes that are critical for cell-cell and cell-matrix adhesion, resulting directly or indirectly in tissue separation/blistering within and beneath the epithelium.   Immunobullous diseases include pemphigus, pemphigoid, pemphigoid gestationis, epidermolysis bullosa acquisita (EBA), linear IgA disease, dermatitis herpetiformis (DH), and bullous lupus erythematosus. Although the various diseases have characteristic clinical and histopathologic features, presentation may be atypical and often demonstrates overlap with other immunobullous diseases or with more common skin diseases such as eczema and urticaria. Accurate diagnosis depends on clinical assessment plus the detection of autoantibodies (tissue bound and/or circulating).     Direct immunofluorescence (DIF) microscopy of a perilesional biopsy is used to detect patterns of immunoglobulins and complement component 3 (C3) that characterize the diseases with epithelial antibodies to adhesion components. DIF is sensitive and is considered a diagnostic standard.   Serum antibody testing using indirect immunofluorescence (IIF) testing and enzyme-linked immunosorbent assays (ELISAs) can be used to distinguish the various disorders more precisely based on autoantibody reactions to specific epithelial antigenic targets.   Although DIF testing of a biopsy specimen may be more sensitive than serum testing for diagnosing immunobullous diseases, either may be positive when the other is negative, and together they offer the most sensitivity. Precise diagnosis is key for prognosis, treatment decisions, and, importantly, because some immunobullous skin diseases are associated with malignancies.  Monitoring serum autoantibody profiles and levels may be useful to follow disease expression and activity, including response to therapy.

Quick Answers for Clinicians

How are the various immunobullous diseases that affect skin and mucous membranes differentiated?

Specific autoantibodies develop in patients with autoimmune blistering diseases. These antibodies show different staining patterns by direct immunofluorescence (DIF) in perilesional tissue biopsy specimens based on reactivity with certain adhesion components that are detected in serum antibodies. For example, desmoglein 1 and 3 autoantibodies in serum are associated with pemphigus, which shows epithelial cell surface staining by DIF in a biopsy specimen, whereas BP180 and BP230 autoantibodies are associated with pemphigoid, which shows epithelial basement membrane zone staining by DIF in a biopsy specimen. See Primary ​Autoantigens Associated with Specific Immunobullous Skin Diseases table for more information.

Which tests are useful for monitoring immunobullous diseases?

Serum antibody profiles and levels often correlate with disease expression and activity in immunobullous diseases; therefore, serologic testing using indirect immunofluorescence (IIF) tests and enzyme-linked immunosorbent assays (ELISAs) enables monitoring of disease and treatment response.  

Where can I find more information on testing for specific immunobullous diseases?

ARUP Consult has additional information on the following diseases: pemphigus, pemphigoid, pemphigoid gestationis, epidermolysis bullosa acquisita (EBA), linear IgA disease, dermatitis herpetiformis, and paraneoplastic pemphigus. It also has algorithms that show testing steps for the various diseases.

Indications for Testing

Laboratory testing for immunobullous diseases is appropriate in the following contexts:

  • Diagnosis of immunobullous diseases (epithelial antibody-associated diseases) in patients with blisters, bullae, or vesicles and erosive lesions of skin and/or mucous membranes,    often accompanied by itching and secondary lesions; also may present as eczema, urticaria, or pruritus without blistering
  • Monitoring of disease activity after established diagnosis of an immunobullous disease

Disease-specific indications and clinical features are listed in the table below.

Disease-Specific Indications and Features
Pemphigus

Pemphigus vulgarisa (mucosal dominant, mucocutaneous, or cutaneous)

Fragile, flaccid bullae that evolve into erosions, crusting

Involvement of mucosa or skin, or both

Nikolsky sign

Pemphigus vegetans (variant of pemphigus vulgaris)

Erythematous, vegetating intertriginous plaques

Pemphigus foliaceusa

Superficial bullae, erosions, and hyperkeratotic scales with crusting

Nikolsky sign

Sparing of mucus membranes

Often in distribution of seborrheic dermatitis

Pemphigus erythematosus (variant of pemphigus foliaceus with features of lupus erythematosus)

Superficial erosions, erythema, crusting, often of malar and seborrheic areas

Also known as Senear-Usher syndrome

Endemic pemphigus (variant of pemphigus foliaceus with genetic and environmental cofactors, primarily in Brazil; also known as fogo selvagem)

Superficial erosions, erythema, crusting, localized to seborrheic areas, head, and upper chest

Generalized, erythrodermic presentation also observed

Pemphigus herpetiformis

Erythematous, bullous, vesicular, pustular, or papular lesions, typically with severe pruritus and in a herpetiform pattern

Mucosal involvement is uncommon

IgA pemphigus

Fragile blisters filled with fluid that evolve into pustules; pruritus

Mucosal involvement is uncommon

Two major subtypes: subcorneal pustular dermatosis and intraepidermal neutrophilic IgA dermatosis

Paraneoplastic pemphigus

Various possible lesion types, including flaccid and/or tense bullae, erosions, urticarial lesions, erythema multiformelike lesions, lichen planus-like lesions, flat scaly papules

Mucosal involvement, often oral and ocular

Pulmonary and gastrointestinal involvement

Pemphigoid

Bullous pemphigoid and variants (urticarial, localized, drug induced)b

Tense bullae and erosions, prominent pruritus (variant forms may not have bullae)

Possible erythematous or urticarial lesions, eczematous dermatitis, pruritus without blisters

Association with neurologic disease (eg, Parkinson disease and multiple sclerosis)

Mucous membrane pemphigoid (cicatricial, ocular, Brunsting-Perry, and antilaminin-332, formerly known as antiepiligrin)

Recurrent bullae affecting mucous membranes as well as skin, with erosions, scarring sequelae

Primarily ocular and oral involvement; Brunsting-Perry variant demonstrates head and neck blistering without mucosal lesions; up to 30% of antilaminin-332 pemphigoid cases have associated malignancy

Anti-p200 pemphigoid (anti-laminin γ1)

Bullae similar to those seen in bullous pemphigoid, vesicles, and urticarial plaques; also palmoplantar, cephalic, and mucosal involvement; frequent development of scars/milia; associated with psoriasis in approximately 30% of cases

Pemphigoid gestationis (previously called herpes gestationis)

Pruritic urticarial papules and bullae on abdomen and trunk that occur during pregnancy or postpartum period; may flare with menses and/or hormonal treatment

EBA

Variants (classical/mechanobullous; nonclassical/nonmechanobullous with features overlapping with bullous pemphigoid; mucous membrane EBA predominantly affects mucosa with squamous epithelia; Brunsting-Perry type involves lesions primarily of head and neck; IgA EBA presents with linear IgA deposits, instead of IgG, and clinical similarity to linear IgA disease, but may have more severe scarring sequelae)

Skin fragility, tense bullae, vesicles, and erosions (in classic or mechanobullous type); healing with scarring and milia

Tense bullae on erythematous, urticarial base (in inflammatory type)

Linear IgA diseasec (Linear IgA bullous dermatosis in adults; chronic bullous disease of childhood in children)

Subepidermal bullae involving skin and adjacent mucus membranes

Tense blisters on skin with “necklacelike” or “string-of-pearls” arrangement

Oral mucosal involvement (common in adult disease) with ulcers and/or erosions

Possible annular or multiformelike lesions

Dermatitis herpetiformis

Grouped vesicles, papules, mainly on elbows, knees, buttocks; primary lesions may be replaced by secondary lesions due to profound pruritus and consequent scratching

Often presents with symmetrical cutaneous involvement

Association with intestinal gluten sensitivity/celiac disease (CD)

Bullous systemic lupus erythematosus

Nonscarring blisters on erythematous or normal skin

Lesions on skin exposed to sun

Lichen planus pemphigoides Lichen planus-like papules with blisters, skin and/or mucosal involvement

aPemphigus vulgaris and pemphigus foliaceus can also be drug induced; implicated drugs include thiol-containing medications, masked thiols, enalapril, and dipyrone.

bPemphigoid is idiopathic in most cases but a minority of cases are drug induced; implicated drugs include antibiotics, ACE inhibitors, sulfasalazine, phenacetin, DPP4is, and checkpoint inhibitors (PD-1/PD-L1 monoclonal antibodies used in treatment for lung cancer and melanoma).

cMost cases of linear IgA disease are idiopathic but some are drug induced; implicated drugs include antibiotics, especially vancomycin, cardiac drugs, NSAIDs, chemotherapeutic agents, antiseizure medications, glibenclamide, diethylcarbamazine, cyclosporine, and lithium.

ACE, angiotensin-converting enzyme; DPP4is, dipeptidyl peptidase-4 inhibitors; γ, gamma; NSAIDs, nonsteroidal anti-inflammatory drugs

Sources: Witte, 2018 ; Otten, 2014 ; Baum, 2014 ; Patricio, 2009 ; Stinco, 2005 ; Kridin, 2019 

Laboratory Testing​

Autoantibody Testing

Serology

In serologic testing for immunobullous skin diseases, the patient serum is incubated with epithelial tissue substrates to determine if there are antibodies in the circulation that target particular components in the substrates being tested. IIF tests and ELISAs are both useful serologic tests for these diseases.  IIF testing enables detection of circulating antibodies and deposition patterns as well as semiquantitative assessment of antibody amounts with limiting-dilution, end-point titers, and ELISAs both identify specific antigenic targets and semiquantify antibodies.  ELISAs have been developed to detect antibodies to antigens common in (but not exclusive to) pemphigus vulgaris and pemphigus foliaceus, bullous pemphigoid and pemphigoid variants, EBA, and other diseases. In addition to ELISAs, immunoblotting and immunoprecipitation are sensitive and specific testing methods that provide serologic confirmation of immunobullous skin diseases, but these methods are are performed in specialty laboratories, mainly research facilities, and are not readily available for diagnostic testing.  

Serum antibody profiles and titers detected by IIF and serum antibody levels as determined by ELISAs correlate with immunobullous disease manifestations and can be used to monitor disease expression and activity. This correlation is particularly relevant in IgG pemphigus variants, including pemphigus foliaceus and pemphigus vulgaris.

Immunopathology​

DIF microscopy of a perilesional biopsy is useful to detect tissue-bound autoantibody or C3 deposition.    (Recent research provides clarification about the diagnostic sensitivity of specific perilesional biopsy locations. ) This testing is considered a diagnostic standard for immunobullous diseases.  The nature and pattern of autoantibody deposition assists in distinguishing the diseases.  For example, in IgG variant pemphigus, IgG and C3 are deposited in a netlike or “honeycomb” pattern in the epidermis/epithelium, and, in pemphigoid, IgG and C3 are deposited in a bandlike, linear pattern along the basement membrane zone. 

Autoantigens Common to Specific Diseases

The table below provides information about the main autoantigens associated with specific immunobullous skin diseases.

Primary Autoantigens Associated With Specific Immunobullous Skin Diseases
Pemphigus
Pemphigus vulgaris Desmoglein 3 with or without desmoglein 1
Pemphigus foliaceus Desmoglein 1
Pemphigus erythematosus Desmoglein 1 and/or desmoglein 3 (antinuclear antibodies also are detected)
Pemphigus vegetans Desmoglein 3 with or without desmoglein 1, desmocollin 3
IgA pemphigus Desmocollin 1, desmocollin 2, desmocollin 3, desmoglein 1 and/or desmoglein 3
Paraneoplastic pemphigus Desmoglein 1, desmoglein 3, desmoplakin 1, desmoplakin 2, envoplakin, periplakin, epiplakin, BP230, alpha-2-macroglobulin-like-protein 1, plectin, and desmocollin 1, desmocollin 2, and desmocollin 3
Pemphigoid
Bullous pemphigoid BP180, BP230
Mucus membrane pemphigoid BP180, p200 (laminin γ1), laminin-332, α6β4 integrin
Anti-p200 pemphigoid p200 (laminin γ1)
Pemphigoid gestationis (formerly called herpes gestationis) BP180 (rarely also BP230)
EBA Type VII collagen
Linear IgA disease LAD-1 (BP180), BP230
Dermatitis herpetiformis Tissue transglutaminase (also known as TG2) and epidermal transglutaminase (also known as TG3)

α, alpha; β, beta; TG2, transglutaminase type 2; TG3, transglutaminase type 3

Sources: Otten, 2014 ; Kridin, 20019 

Additional Disease-Specific Testing Information

See individual ARUP Consult topics for specific testing recommendations for various immunobullous diseases.

Monitoring

Serum antibody testing using IIF and ELISA enables monitoring of disease activity. Patterns and relative antibody titers by IIF are useful to determine expression profiles that relate to disease manifestations. Autoantibody levels as determined by ELISAs often correlate with disease activity and are useful in monitoring response to therapy after an established diagnosis.  

Tests for Monitoring Treatment Response in Specific Immunobullous Diseases
Disease Tests Comments
Pemphigoid Pemphigoid Antibody Panel 0092001 Testing for BP180 and BP230 antibodies (IgG) by ELISA may be appropriate in some patients to monitor disease activity; substitute testing with pemphigoid antibody panel (includes IgG BP180 and IgG BP230 antibody levels) intermittently to detect changing antibody patterns, which may have implications for disease expression
Pemphigus (foliaceus, erythematosus, vulgaris, or vegetans) Pemphigus Antibody Panel, IgG 0090650 Testing for desmoglein 1 and desmoglein 3 antibodies (IgG) by ELISA may be appropriate in some patients to monitor disease activity; substitute testing with pemphigus antibody panel (includes IgG desmoglein 1 and IgG desmoglein 3 antibody levels) intermittently to detect changing antibody patterns, which may have implications for disease expression
IgA pemphigus Pemphigus Antibodies, IgA by IIF 0092106 Testing for IgA cell surface antibodies may be appropriate, not only for IgA pemphigus, but to monitor disease activity in nonclassical pemphigus presentations with both IgA and IgG cell surface antibodies
Paraneoplastic pemphigus

Paraneoplastic Pemphigus (Paraneoplastic Autoimmune Multiorgan Syndrome) Antibody Screening Panel 0092107

If increased, Desmoglein 1 and Desmoglein 3 (Pemphigus) Antibodies, IgG by ELISA 0090649 and/or Bullous Pemphigoid (BP180 and BP230) Antibodies, IgG by ELISA 0092566
EBA

Basement Membrane Zone (Epithelial) Antibodies, IgG by IIF 0092056 AND Collagen Type VII Antibody, IgG by ELISA 2010905

OR

Basement Membrane Zone and Cell Surface (Epithelial) Antibodies, IgG and IgA by IIF 0092057 AND Collagen Type VII Antibody, IgG by ELISA 2010905

OR

Basement Membrane Zone Antibody Panel 3001410
Testing for type VII collagen antibody (IgG) by ELISA may be appropriate in some patients to monitor disease activity; intermittently test with epithelial skin antibody panel and type VII collagen antibody (IgG) by ELISA or basement membrane zone antibody panel to detect changing antibody patterns as well as levels, which may have implications for disease expression
Linear IgA disease Basement Membrane Zone (Epithelial) Antibodies, IgA by IIF 0092057

OR

Basement Membrane Zone and Cell Surface (Epithelial) Antibodies, IgG and IgA by IIF 0092056

Dermatitis herpetiformis Celiac Disease Reflexive Cascade 2008114 and Epidermal Transglutaminase (etG/tTG3) Antibody, IgA by ELISA 2010902
Pemphigoid gestationis Pemphigoid Gestationis, Complement-Fixing Basement Membrane Antibodies (Herpes Gestationis Factor) 0092283

ARUP Laboratory Tests

Additional detail about each test listed below can be found in the ARUP Immunobullous Disease Testing Comparison table.

Immunopathologic Testing (DIF)

Use with serum immunobullous disease/epithelial antibody testing and formalin-fixed tissue histopathology for assessment of pruritic, urticarial, blistering, and/or erosive disorders

Use with formalin-fixed tissue histopathology for assessment of inflammatory, immune-mediated cutaneous disease

Optimal specimen location and complementary serum testing and/or histopathology examination vary according to disease type; note that specimen location and transport medium/fixative are different for direct immunofluorescence testing and fixed-tissue histopathology

Recommended Serologic Testing

Semiquantitative IIF and Semiquantitative ELISA (With Biopsy DIF in Initial Assessment)

Use as initial comprehensive testing panel to aid in the diagnosis of and distinguishing among skin and mucous membrane disorders that present with blistering, erosions, eczema, pruritus, and/or urticaria

Use for assessment of suspected epithelial antibody-associated immunobullous diseases, pemphigoid and pemphigus and their variants, that are not clinically distinguishable, have nonspecific features, potentially express overlapping epithelial antibodies, and/or are indicated by concurrent DIF biopsy

Components: BMZ antibodies, IgG by IIF; BMZ antibodies, IgA by IIF; BP180 and BP230 antibodies, IgG by ELISA; collagen type VII antibodies, IgG by ELISA; cell surface antibodies, IgG by IIF; desmoglein 1 and 3 antibodies, IgG by ELISA; cell surface antibodies, IgA by IIF

Use as the preferred initial diagnostic panel for suspected BMZ antibody-associated skin and mucous membrane disorders that present with blistering, erosions, eczema, urticaria, pruritus, and/or mucositis

May be indicated by concurrent DIF biopsy

Alternatively, order the comprehensive Immunobullous Disease Antibody Panel for initial serum diagnostic assessment of epithelial antibody-associated diseases, pemphigoid, pemphigus, and their variants

Components: BMZ antibodies, IgG by IIF; BMZ antibodies, IgA by IIF; BP180 and BP230 antibodies, IgG by ELISA; collagen type VII antibodies, IgG by ELISA

Use as the preferred serum antibody panel to assess and monitor IgG pemphigus variants (includes pemphigus foliaceus and pemphigus vulgaris), which present with blistering and erosive disease that affect skin and mucous membranes

Testing should be correlated with concurrent DIF biopsy

Components: Cell surface antibodies, IgG by IIF; desmoglein 1 and IgG desmoglein 3 antibodies, IgG by ELISA

Use to monitor linear IgG and IgA BMZ antibody-associated diseases and IgG and IgA cell surface antibody-associated diseases in which antibody levels by ELISAs may not be increased and/or to assess for changing patterns of epithelial antibody expression

May be used as general initial serum test for immunobullous diseases; however, for more sensitive and specific serum testing with ELISAs for pemphigoid and EBA or for IgG variant pemphigus, refer to Basement Membrane Zone Antibody Panel or Pemphigus Antibody Panel, IgG

Components: BMZ antibodies, IgG by IIF; BMZ antibodies, IgA by IIF; cell surface antibodies, IgG by IIF; pemphigus antibodies, IgA by IIF

Use to assess and monitor paraneoplastic pemphigus, a rare paraneoplastic disease associated with lymphoproliferative disorders/malignancies and demonstrating clinical features of severe pemphigus

Testing should be correlated initially with concurrent DIF biopsy, histopathologic examination of formalin-fixed tissue, and assessment of other epithelial antibodies

Consider ordering concurrently with Immunobullous Disease Antibody Panel for broad epithelial antibody assessment

Components: cell surface antibodies, IgG by IIF; BMZ antibodies, IgG by IIF

Use as antibody test for initial assessment and disease monitoring of DH associated with celiac disease (CD) and to discriminate among the immunobullous skin diseases

Quantitative nephelometry, semiquantitative IIF and ELISA; IgA mg/dL, positive limiting-dilution end-point antibody titer(s) (IIF) and antibody level in units (ELISA)

Use with epidermal transglutaminase antibody, IgA, and with basement membrane zone and pemphigus panel tests or with Immunobullous Disease Antibody Panel and epidermal transglutaminase antibody, IgA testing for DH or other concurrent immunobullous disease

Components: quantitative nephelometry for immunoglobulin A with one or more reflexive tests that may include semiquantitative IIF for IgA endomysial antibodies; semiquantitative ELISAs for IgA and IgG antibodies to tissue transglutaminase and deamidated gliadin peptide (DGP)

Use to assess and monitor DH

Testing should be correlated initially with concurrent DIF biopsy

Because most patients with DH have associated CD, testing should be performed in conjunction with testing for CD

For initial diagnosis and assessment of disease progression/changes and to distinguish from other immunobullous diseases with epithelial antibodies, order concurrently with serum Immunobullous Disease Antibody Panel

Use to assess and monitor pemphigoid, pemphigoid variants, and linear IgA disease and to discriminate among the immunobullous diseases with epithelial BMZ antibodies

May be indicated by concurrent DIF biopsy; preferred initial diagnostic serum panel is Basement Membrane Zone Antibody Panel

Components: BMZ antibodies, IgG by IIF; BMZ antibodies, IgA by IIF; BP180 and BP230 antibodies, IgG by ELISA

Other Serologic Testing

Semiquantitative IIF and Semiquantitative ELISA

Use to assess and monitor IgA BMZ antibodies in patients with linear IgA disease, including linear IgA bullous dermatosis and chronic bullous disease of childhood, and IgA variant EBA

Testing should be correlated initially with concurrent DIF biopsy

For initial linear IgA disease diagnosis, serum Basement Membrane Zone Antibody Panel or Immunobullous Disease Antibody Panel is preferred

Use to assess and monitor IgG BMZ antibodies in patients with pemphigoid, pemphigoid variants/subtypes, and EBA, especially those with normal relevant IgG BP180, IgG BP230, and IgG type VII collagen antibody levels by ELISAs

Testing should be correlated initially with concurrent DIF biopsy

For initial pemphigoid or EBA diagnosis, a more comprehensive serum panel is preferred; refer to Immunobullous Disease Antibody Panel

Use to monitor disease in patients diagnosed with pemphigoid and increased IgG BP180 and/or BP230 antibody levels

For initial pemphigoid diagnosis that discriminates among immunobullous diseases and for assessment of disease progression/changes and intermittent monitoring, the Basement Membrane Zone Antibody Panel or Immunobullous Disease Antibody Panel is preferred

Use to monitor disease in patients diagnosed with EBA or bullous lupus erythematosus with increased IgG type VII collagen antibody levels

For initial diagnosis, including discrimination among various immunobullous diseases and assessment of disease progression/changes and intermittent monitoring, the Immunobullous Disease Antibody Panel or Basement Membrane Zone Antibody Panel is preferred

Use to monitor disease in patients diagnosed with various pemphigus variants and increased IgG desmoglein 1 and/or IgG desmoglein 3 antibodies; antibody levels correlate with disease activity

For initial diagnosis, Pemphigus Antibody Panel, IgG has greater diagnostic sensitivity and specificity and is preferred in the assessment of disease progression/changes and for intermittent monitoring of IgG pemphigus variants

For more comprehensive evaluation, consider Immunobullous Disease Antibody Panel

Use to assess and monitor cell surface antibodies in patients with IgG pemphigus variants with normal IgG desmoglein 1 and IgG desmoglein 3 antibody levels

Testing should be correlated initially with concurrent DIF biopsy

For comprehensive testing, consider ordering the Immunobullous Disease Antibody Panel

Use to assess and monitor IgA pemphigus or other nonclassical pemphigus subtypes with both IgA and IgG cell surface antibodies

Testing should be correlated with concurrent DIF biopsy

Consider ordering concurrently with serum Pemphigus Antibody Panel, IgG if other types of pemphigus are diagnostic considerations

Medical Experts

Contributor

Leiferman

Picture of Kristin M. Leiferman, MD

 

Co-Director, Immunodermatology Laboratory, Professor of Dermatology, and Adjunct Professor of Pathology, University of Utah
Medical Director, Immunodermatology, ARUP Laboratories

References

Additional Resources