This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
Page 1
1
AP119 Immunohistology inDermatopathology
Mark R. Wick, MDUniversity of VirginiaCharlottesville, VA
• Linear IgA disease• Bullous disease of childhood
16
DERMATITIS HERPETIFORMIS:Clinicopathologic Features
DERMATITIS HERPETIFORMIS:Clinicopathologic Features
• Onset usually in adulthood• Intensely itchy, pustular and bullous lesions that
tend to cluster on the dorsal extremities• Association with other immunologic or quasi-immune diseases such as lymphocytic thyroiditis,
sprue, & pernicious anemia• Responds to dapsone and gluten-free diet
• Biopsy shows aggregates of neutrophils in the papillary dermis, becoming confluent and
detaching the overlying epidermis
Page 9
17
SIMILARITIES & DIFFERENCES IN THE IgA-RELATED BULLOUS DERMATOSESSIMILARITIES & DIFFERENCES IN THE
IgA-RELATED BULLOUS DERMATOSES
• DH, LID, & BDC all show an association with the HLA allele B8
• Pattern of IgA deposition differs; granular and discontinuous at BMZ in DH; linear at
BMZ in LID/BDC• Only patients with DH show circulating
antibodies to smooth muscle (anti-endomysial Aby) & have intestinal disease
clinically• The 3 diseases are considered to
represent a “family” of conditions
18Dermatitis Herpetiformis
Page 10
19Direct Immunofluorescence for IgA in Dermatitis Herpetiformis
20Direct Immunofluorescence for IgA in Linear IgA Dermatosis
Page 11
21
BULLOUS PEMPHIGOIDClinicopathologic FeaturesBULLOUS PEMPHIGOIDClinicopathologic Features
• Bimodal; seen in childhood and again in elderly patients
• Tense bullae that break spontaneously• Trunk, extremities, and mucosal surfaces
affected relatively equally• In the eyes, the “cicatricial” variant is
important• Subepidermal cleft microscopically;
mixed, usually scant inflammatory infiltrate• Linear IgG and/or C3 at the BMZ by DIF
22Bullous Pemphigoid
Page 12
23Direct Immunofluorescence for IgG in Bullous Pemphigoid
24
EPIDERMOLYSIS BULLOSA ACQUISITA
Clinicopathological Features
EPIDERMOLYSIS BULLOSA ACQUISITA
Clinicopathological Features• Generally more restricted in lesional
distribution than BP• Rare cases of disseminated EBA do resemble
pemphigoid clinically• Potential association with visceral malignancy,
unlike BP• May be histologically-identical to BP
• Definable as different from pemphigoid only by detailed IHL
Page 13
25
Epidermolysis Bullosa Acquisita
26
HERPES GESTATIONISHERPES GESTATIONIS
• Basically a form of bullouspemphigoid that occurs during or immediately following pregnancy• Differs from classic BP only in showing a restriction to C3 (no
Ig) at the BMZ by DIF
Page 14
27
A PRACTICAL ALTERNATIVE TO SALINE SPLIT SKIN PREPSA PRACTICAL ALTERNATIVE
TO SALINE SPLIT SKIN PREPS• DIF on patient biopsies; those with linear
staining for IgG at BMZ and subepidermalblisters are then studied further to
distinguish BP from EBA• Paraffin sections are stained for collagen
type IV; BP antigen is superficial to CIV (which is in lamina densa), and EBA
antigen is deep to it. CIV is therefore in roof of EBA blisters & base of
BP blisters
28Immunohistology for Collagen Type IV in Lesional Skin of Bullous Pemphigoid
Page 15
29
CUTANEOUS LUPUS ERYTHEMATOSUS
Clinicopathologic Features
CUTANEOUS LUPUS ERYTHEMATOSUS
Clinicopathologic Features
• Scaly, erythematous lesions, particularly in sun-exposed skin areas
• Discoid form is limited to the skin• Histology is generally that of a lichenoid &
interface dermatitis, making IHL desirable for further Dx
• DIF shows granular deposition of Igand/or C3 at the epidermal BMZ
• “Lupus band” is present in systemic form
30
BULLOUS LUPUS ERYTHEMATOSUS
Page 16
31Cutaneous Lupus Erythematosus– Direct Immunofluorescence for IgG
32
IHL IN OTHER NON-BULLOUS DISEASES OF THE SKIN
IHL IN OTHER NON-BULLOUS DISEASES OF THE SKIN
• Lichen planus/planopilaris-- deposition of IgM, IgG, IgA, and/or C3 on “colloid bodies”
(damaged keratinocytes) at or above the BMZ; usually not necessary for definitive diagnosis
• Vasculitides-- deposition of immune complexes in arterioles or venules of the dermis; Ig class
varies with type of vasculitis• Drug-induced dermatitides show no consistent
pattern of immunological abnormality
Page 17
33
Lichen planus– Hematoxylin& Eosin Stain and Direct
ImmunofluorescenceFor IgM
34
Cinical & HistologicImages of Cutaneous
Small-VesselVasculitis
Page 18
35
Direct Immunofluorescence for IgAIn Henoch-Schonlein Vasculitis of Skin
36
REASONS FOR DESIRABILITY OF IMMUNOSTAINS FOR
INFECTIOUS AGENTS
REASONS FOR DESIRABILITY OF IMMUNOSTAINS FOR
INFECTIOUS AGENTS1. In-situ demonstration of infectious organisms in the
context of tissue responses in histologic sections
2. Rapid, specific identification of organisms that may be difficult to
culture or extremely slowly-growing
Page 19
37
COMMERCIAL IMMUNOSTAINS FOR VIRAL AGENTS IN
CUTANEOUS HUMAN DISEASE
COMMERCIAL IMMUNOSTAINS FOR VIRAL AGENTS IN
CUTANEOUS HUMAN DISEASE
• Herpes simplex I & II• Zoster-Varicella virus
• Cytomegalovirus• Human papillomavirus (pan-capsid