IgA pemphigus

Author:  Esther Wang, Medical Student, University of Sydney, Sydney, Australia; Professor Dedee F. Murrell, Head, Department of Dermatology, St George Hospital, University of New South Wales, Sydney, AustraliaDermNet New Zealand Editor-in-Chief: A/Prof Amanda Oakley, Dermatologist, Hamilton, New Zealand. February 2018. 

What is IgA pemphigus?

IgA pemphigus is an autoimmune blistering disorder. It is also called intercellular IgA dermatosis and immunoglobulin A pemphigus among other names.

IgA pemphigus has two major subtypes.

  • Subcorneal pustular dermatosis (SPD)-type
  • Intraepidermal neutrophilic (IEN)-type.

A new classification describes 5 subtypes of IgA pemphigus:

  • SPD-type
  • IEN-type
  • IgA-pemphigus vegetans
  • IgA-pemphigus vulgaris
  • Unclassified.

Who gets IgA pemphigus?

IgA pemphigus is very rare. It most commonly affects the middle aged and elderly but it can affect any age, with a case reported in a child one month of age.

What are the clinical features of IgA pemphigus?

The clinical features of IgA pemphigus include blisters, pustules, erythema, erosions and vegetating lesions.

  • The first signs are flaccid vesicles and pustules.
  • These rupture to form erosions and crusted plaques.
  • The eruption tends to follow an annular pattern.

IgA pemphigus appears to favour the trunk, upper and lower extremities, axillae and groin. Mucosal involvement is very rare.

What is the cause of IgA pemphigus?

The exact cause of IgA pemphigus is unclear.

  • IgA autoantibodies bind to desmogleins or desmocollins.
  • In SPD-type IgA pemphigus, the autoantigen is described as desmocollin 1, one of the desmosomal cadherins.
  • In at least some cases of IEN-type IgA pemphigus, the autoantigens are desmogleins 1, desmoglein 3, and an unspecified transmembrane protein.

What is the differential diagnosis for IgA pemphigus?

Other conditions that should be considered in the differential diagnosis include:

How is IgA pemphigus diagnosed?

An autoimmune blistering disease or autoinflammatory pustular disease may be suspected clinically from the clinical features, often after the eruption has failed to clear with antibiotics.

The diagnosis of IgA pemphigus requires skin biopsy for histology and direct immunofluorescent testing.

  • Skin biopsy reveals an intraepidermal blister. There is a mixed dermal inflammatory infiltrate, with intraepidermal neutrophil infiltration.
  • Direct immunofluorescence of a skin biopsy of normal appearing skin close to the area of blistering reveals IgA deposition in epidermal keratinocyte cell membranes.

Indirect immunofluorescence testing of serum can show IgA antikeratinocyte cell-surface antibodies. IgG antikeratinocyte cell-surface antibodies have also been reported.

What is the treatment for IgA pemphigus?

The main medications used to treat IgA pemphigus are systemic steroids and dapsone.

Since few cases of IgA pemphigus have been described, the most effective treatment is unknown. Other medications worth considering include:


Related Information


  • Hashimoto T, Teye K, Ishii N. Clinical and immunological studies of 49 cases of various types of intercellular IgA dermatosis and 13 cases of classical subcorneal pustular dermatosis examined at Kurume University. British Journal Of Dermatology 2016, 176(1), 168-175. Journal.
  • IgA Pemphigus Workup: Laboratory Studies, Other Tests, Procedures. Emedicine.medscape.com. Retrieved 26 June 2017. http://emedicine.medscape.com/article/1063776
  • Ishii N, Ishida-Yamamoto A, Hashimoto T. Immunolocalisation of target autoantigens in IgA pemphigus. Clinical and Experimental Dermatology 2004, 29(1), 62-66. PubMed.
  • Liu Y, Tzung T, Lin C, Lo P. IgA Pemphigus: Subcorneal Pustular Dermatosis Type - A case report with vesicle and pustular eruption for 13 years cured with dapsone in 3 weeks. Dermatologica Sinica 2008, 26, 258-263. PDF file.
  • Porro A, Caetano L, Maehara L, Enokihara M. Non-classical forms of pemphigus: pemphigus herpetiformis, IgA pemphigus, paraneoplastic pemphigus and IgG/IgA pemphigus. Anais Brasileiros De Dermatologia 2014, 89(1), 96-106. Journal.
  • Tsuruta D. Intercellular IgA dermatosis. British Journal of Dermatology 2017, 176(1), 13-14. Journal.

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