Acantholysis

Acantholysis is a feature seen in the epidermis as an isolated feature in some skin cancers including solar ks, SCCs and even in melanoma but also in Warty dyskeratoma.  It is a major finding in Hailey Hailey disease, Darier's disease and in Pemphigus but is also seen to a lesser extent in Grover's disease. Rarely acantholysis is seen in Pityriasis rubra pilaris.

Acantholysis is most marked in Pemphigus vulgaris and in Hailey Hailey disease. The latter is a genetic disorder where the desmoglien proteins holding the keratinocytes together are mostly missing.

  Intra epidermal blistering disorders

 If acantholysis consider Pemphigus vulgaris, Darier's disease, and Hailey Hailey disease and Grovers. Herpes infections should show features of Ballooon degeneration of keratinocytes. Other Pemphigus variants include Pemphigus erythematosus, Pemphigus vegetans and Paraneoplastic Pemphigus.

 Pemphigus Vulgaris and variants

 Clinical Pemphigus vulgaris presents initially in elderly patients with oral ulceration followed by flacid blisters and crusts on the trunk and sites of frictional trauma.It can involve the mouth and oesophagus. Histology Acantholysis which is suprabasal with villus formation . Involvement of a hair follicle is virtually diagnostic of PV. Tombstone formation of basal cells adherent to the basement membrane. These dermal papillae are called villi for this reason.Eosinophilic or neutrophilic spongiosis early in the blistering process. You dont see corps ronds or grains in Pemphigus! Can biopsy virtually anywhere.

Paraneoplastic Pemphigus has intraepidermal acantholysis but also basal layer vacuolisation and necrotic keratinocytes.

  Pemphigus vegetans This curious variant of pemphigus vulgaris is seen in the flexures and scalp with marked epidermal proliferation and abscess formation looking very infected. Histologically there is marked acanthosis and even pseudoepitheliomatous hyperplasia with intra epidermal neutrophilic abscesses but eosinophils can also be seen.

. View this Virtual Slide of Pemphigus Vegetans

 DD Hailey Hailey ( widespread acantholysis), Grovers (Localised acantholysis), Dariers disease ( dyskeratotic cells, corps ronds and grains). Clinical Flexural crusts and linear erosions particularly axillae and groin and under breasts, back of the neck. Family history. Histology Very extensive acantholysis with no follicular involvement. Some mild dyskeratosis. Dilapidated brick wall. Extensive acantholysis, Rare foci of dyskeratosis, Neg immunofluorescence. 

Consider also acantholytic disorder of the genito crural area.

View this Virtual Slide of Hailey Hailey Disease DX Path on Hailey Hailey Diseases 

View the video below on Hailey Hailey disease Histology