Immunofluorescence using both direct techniques and indirect techniques is the most reliable method to diagnosis pemphigus.
Because of the rare occurrence of pemphiguslike antibodies, pemphigus cannot be diagnosed by indirect immunofluorescence (IIF) alone and must be confirmed by direct immunofluorescence (DIF)..
The building block cells of the epidermis are called keratinocytes.
These cells are cemented together at special sticky spots called desmosomes.
In pemphigus foliaceus, autoantibodies bind to a protein called desmoglein-1, which is found in desmosomes in the keratinocytes near the top of the epidermis..
Diagnosis of pemphigus foliaceus is by biopsy of a lesion and adjacent (perilesional) unaffected skin that shows IgG autoantibodies against the keratinocyte cell surface via direct immunofluorescence..
The low power view of the histology of pemphigus foliaceus is of a superficial epidermal blistering process.
The low power clues include loss of the stratum corneum, increased prominence of the granular layer, or visible superficial epidermal separation with blister formation (Figure 1)..
Pemphigus erythematosus: In this variant the histology is that of pemphigus foliaceus, with the additional immunoflouorescence finding of basal membrane IgG +/- C3 in addition to the intercellular distribution.
Antinuclear antibodystudies are also frequently positive.
IgA pemphigus: Typically there is a more prominent subcorneal neutrophilic infilt.
The low power view of the histology of pemphigus foliaceus is of a superficial epidermal blistering process.
The low power clues include loss of the stratum corneum, increased prominence of the granular layer, or visible superficial epidermal separation with blister formation (Figure 1).
At higher magnification subtle acanthloysis and spongiosis ca.
Direct immunofluorescence is a critical component of the workup, but requires a separate specimen transported in appropriate media.
A positive result is the presence of intercellular IgGand C3 predominantly within the superficial layers of the epidermis (Figure 6).
The classical lesions of pemphigus foliaceous are large pustules that span multiple hair follicles ( 1, 4 ).
The pustules often begin as papules and rapidly progress to crusts and erosions ( 1, 4 ).
Lesions occur most commonly on the trunk, inner pinnae, face, and footpads and are generally symmetrical ( 4, 5 ).
As an acquired form of pemphigus, pemphigus foliaceus is caused by immunoglobulin G (IgG) antibodies directed against desmoglein-1 (Dsg1) found in the granular layer of the epidermis.
The low power view of the histology of pemphigus foliaceus is of a superficial epidermal blistering process.
The low power clues include:
Most cases of pemphigus foliaceus are presumed to be idiopathic.
Immunosuppressive drugs are the most common treatment, and while recurrence is common, prognosis is fair to good.
Pemphigus foliaceus (PF) is the most common autoimmune skin disease in dogs and cats.
