Skin Biopsy for Immunofluorescence
Immunofluorescence can only be performed on fresh unfixed tissue
The fresh specimen must be wrapped in a piece of saline moistened gauze for transport to the laboratory. Wrapping prevents drying which can introduce false staining. The specimen must be delivered to the laboratory as soon as possible (within 1 hour).
If in doubt telephone the laboratory (907 62476) before removing the specimen, so that advice can be given before it is too late.
Immunologic reactions play a major role in the pathogenesis of many skin diseases. The immunologic abnormalities found in skin and mucous membranes of patients with certain bullous (blister) disorders (pemphigus and pemphigoid), in which vesicles or bullae occur, and in the different forms of lupus erythematosus are disease specific. The distinct immunopathogenic characteristics of these diseases mean the detection of deposits of immunoglobulin and complement components in both lesional and normal skin by direct immunofluorescent techniques is of great value in establishing a diagnosis.
The extracellular antigens of most value in immunodermatology are IgA, IgG, IgM, the complement proteins (C3C, C4 & C1q) and fibrinogen. The immunoreactivity of these antigens is deleteriously affected by formalin fixation to varying degrees.
Whenever possible, biopsy a single fresh small blister including adjacent clinically uninvolved skin (perilesional).
> For a large blister, biopsy edge of blister and adjacent uninvolved skin (perilesional).
> Cut the perilesional end and send for IF studies and the remaining blister for histology.
> For uninvolved skin, a 3-mm punch biopsy is sufficient.
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Condition
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Biopsy Site(s) for IF
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Pemphigus (All forms)
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Perilesional Uninvolved (Buttock)
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Pemphigoid (All forms)
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Perilesional Uninvolved (Thigh or Arm)
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Pemphigoid (Herpes) Gestationis
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Perilesional
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Linear IgA Bullous Dermatoses (LAD & CBDC)
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Perilesional Uninvolved (Buttock)
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Epidermolysis Bullosa Acquisita
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Perilesional
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Discoid Lupus Erythematosus
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Lesional
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Systemic Lupus Erythematosus
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Lesional & Uninvolved(Non-sun exposed [Buttock])
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Bullous Systemic Lupus Erythematosus
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Perilesional
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Dermatitis Herpetiformis
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Uninvolved (Buttock)
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Lichen Planus
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Lesional
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Porphyria
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Lesional
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Vasculitis
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Lesional
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Amyloid
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Lesional
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