Skin Pathology III Pemphigus Vulgaris Type II Hypersensitivity

Skin Pathology III

Pemphigus Vulgaris • Type II Hypersensitivity Reaction • Ig. G Autoantibodies against Desmogleins that disrupt intercellular adhesions and result in the formation of blisters. • Loss of intercellular attachment acantholysis blister • Direct Immunofluorescence Test (DIF): • Epidermal Fishnet Pattern of Ig. G and C 3

Pemphigus Foliaceus • Subcorneal Acantholysis • More Superficial • Less Severe • Uncommon • “Crushed Cornflake” Plaques • Mostly on trunk.

Bullous Pemphigoid • Most Common Autoimmune Blistering Disorder. • Type II Hypersensitivity Reaction • Antibodies against hemidesmosomes: • BPAG 1 (BP 230) • BPAG 2 (BP 180) • Type XVII Collagen - Pathogenic • Tense Vesicles/Bullae under the skin with clear fluid. • Do not rupture easily – deep • Histology: • Eosinophillic Spongiosis • Subepidermal Blister Formation • Direct Immunofluorescence: • Linear Ig. G and C 3 deposition along the Basement Membrane

Dermatitis Herpetiformis • Extremely pruritic papules and vesicles. • Cutaneous manifestation of Gluten Sensitivity. • Celiac Disease: Gluten (Gliadin) Sensitive Enteropathy • Ig. A Antibody reaction with anchoring fibrils of the derma papillae at the Basement Membrane. • Vesicle + Microabscess Formation

Impetigo • Superficial Erosions and “honey-yellow” crusted lesions. • Highly Contagious • Most commonly caused by Staph. Aureus • Self-Limited = 2 Weeks, Non-Scarring

Verruca Vulgaris • Common Lesions in Children • Soles of Feet, Fingers • Description: • Gray-White Tan • Flat, Convex • Papules, Rough, Pebble-Like Surface • Cause: • Human Papilloma Virus (HPV) • Types: • Verruca Plana: Flat Wart on Face and Dorsal Hand • Verruca Planataris (Soles) • Verruca Palmaris (Palms) • Condyloma Accuminatum (Venereal Wart) • Penis, Genitalia, Urethra, Perianal Area, Rectum • Cauliflower-Like Masses HPV 16 and HPV 18: associated with high risk of Squamous Carcinoma Histology: Verrucous Papillary Hyperplasia Hyperkeratosis Tiers of Parakeratosis + Hemorrhage Koliocyte: Superficial Vacuolated Cells Keratohyaline Granules

Molluscum Contagiosum • Common, Contagious, Self-Limiting • Caused by Poxvirus • Pearly, Umbilicated Papules • Histology: • Cup-like, Verruvous Epidermal Hyperplasia with “Molluscum Bodies” of Stratum Granulosum and Corneum. • Molluscum Bodies: Eosinophillic Cytoplasmic Inclusions

Herpes Simplex Virus • Latent Infections (Ganglion) • Types: • HSV 1: Oral Mucosa • HSV 2: Genital Herpes • Varicella Zoster Virus: Chicken Pox • Reactivation: Shingles • Unilateral vesicles in Dermatomal Distribution. • Description: • Grouped Vesicles on an Erythematous Base • Histology: • Vesicles + Ulcerations • Inflammation + Neutrophils • Ballooning Degeneration • Enlarged Keratinocytes: • Steel-Gray Nuclei • Multinucleated • Margination of Chronatin • Molded Nuclei

Scabies • Pruritus, exacerbated by hot showers and nighttime. • Small, Erythematous Papules, Vesicles, Excoriations. • Finger Web Spaces • Burrow: Wavy, Threadlike, Grey-White

Superficial Fungal Infections • Found in Stratum Corneum of Epidermis • Types: • Tinea capatis: Scalp, children, hairless patches • Tinea barbae: Adult beard • Tinea corporis: Common, body surface, all ages but mostly children. • Tinea cruris: Inguinal areas due to friction (obese) • Tinea pedis: Very Common, feet • Onychomycosis: Infection of the nail • Tinea Versicolor: Upper Trunk, yeast • Description: • Well Demarcated • Pink-Red Patch • Peripheral Scaling • Histology: • PAS Stain showed the Hyphae/Yeasts

Arthropod Bite Reaction • Varied Appearance • Histology: • Superficial and Deep Perivascular Lymphohistiocytic Inflammation with Eosinophils and Neutrophils • Type I or Type IV Hypersensitivity Reaction

Pemphigus Foliaceus Subcorneal Acantholysis “Leaves on a tree”

Bullous Pemphigoid Blister is Subepidermal. Clean cut – no tombstone row.

Impetigo Honey-Crusted Erosions S. Aureus Contagious

Pemphigus Vulgaris Tombstone Row Lymphohistiocytic Inflammation w/ Eosinophils Suprabasilar Acantholysis Ig. G Anti-Desmoglein

Pemphigus Vulgaris Ig. G/C 3 Deposits Fishnet Appearance near Basal Layer

Pemphigus Foliaceus DIF: Ig. G more superficial. Fishnet Pattern

Pemphigus Vulgaris Superficial flaccid vesicles that easily rupture with deep, extensive erosions.

Pemphigus Foliaceus Crushed Cornfake Plaques More Superficial

Bullous Pemphigoid Linear Ig. G and C 3 Deposition along the Basement Membrane

Bullous Pemphigoid Blister is Subepidermal. No tombstone row.

Dermatitis Herpetiformis Microabscess Formation Gluten Sensitivity

Dermatitis Herpetiformis DIF: Ig. A Deposition with anchoring fibrils of the dermal papillae at the Dermal-Epidermal Junction

Bullous Pemphigoid Deeper blisters Do not rupture easily

Verruca Vulgaris Papules with a rough, pebble-like surface. HPV

Bullous Pemphigoid Deeper blisters. Do not rupture easily.

Scabies Burrow: Wavy, Thread-Like

Dermatitis Herpetiformes Microabscess Formation Gluten Sensitivity

Dermatitis Herpetiformis Extremely Pruritic papules and vesicles. Gluten Sensitivity

Bullous Pemphigoid Subepidermal blister formation without acantholysis. Anti-Hemidesmosomes (BPAG 1 & BPAG 2)

Dermatitis Herpetiformis Extremely pruritic papules and vesicles. Gluten Sensitivity

Pemphigus Vulgaris Tombstone Row Lymphohistiocytic Inflammation w/ Eosinophils Suprabasilar Acantholysis Ig. G Anti-Desmoglein

Molluscum Contagiosum Pearly, Umbilicated Papules Caused by Poxvirus

Herpes Simplex Virus Cervix Sample Multinucleated Margination of Chromatin Molded Nuclei

Bullous Impetigo Honey-Crusted Erosions S. Aureus Contagious

Verruca Vulgaris Flat Warts Commonly on Dorsal Surfaces of the Hands Verruca Plana HPV

Verruca Vulgaris Papules with a rough, pebble-like surface HPV

Verruca Vulgaris Condensed Keratohyaline Granules and jagged Eosinophillic Intracytoplasmic Keratin Aggregates from Viral Cytopathic Effects. HPV

Verruca Vulgaris Condensed Keratohyaline Granules and jagged Eosinophillic Intracytoplasmic Keratin Aggregates from Viral Cytopathic Effects. HPV

Verruca Vulgaris Papules with Rough, Pebble-Like Surfaces HPV

Verruca Vulgaris Koliocytes: Superficial epidermal cells with pale halos surrounding nuclei. Indicates cell changes associated with HPV Infection

Verruca Vulgaris Keratohyaline Granules HPV

Molluscum Contagiosum Pearly, Umbilicated Papules Caused by Poxvirus

Pemphigus Vulgaris Superficial Flaccid Vesicles that easily rupture with deep, extensive erosions.

Molluscum Contagiosum Cup-Like Verrucous Epidermal Hyperplasia with “Molluscum Bodies” of Stratum Granulosum and Stratum Corneum Caused by Poxvirus

Herpex Simplex Virus Lung Sample Multinucleated Margination of Chromatin Molded Nuclei

Herpes Zoster Ophthalmic Zoster Intense, Painful Prodrome with Pruritis

Scabies Mite is burrowed in the skin. Spines

Molluscum Contagiosum Molluscum Bodies: Eosinphillic Cyplasmic Inclusions Caused by Poxvirus

Scabies Erythematous Papules, Vesicles, Excoriations Finger-Web Spaces

Herpes Zoster Ophthalmic Zoster Intense, Painful Prodrome with Pruritis

Herpes Simplex Virus HSV-1 Grouped Vesicles on an Erythematous Base

Pemphigus Vulgaris Suprabasilar separation and blister formation Suprabasilar Acantholysis Ig. G Anti-Desmoglein

Arthropod Bite Reactions Very variable.

Herpes Simplex Virus HSV-1 Grouped Vesicles on an Erythematous Base

Arthropod Bite Reaction Eosinophils Neutrophils Lots of Inflammation

Herpes Zoster Reactivation Shingles Dermatomal Distribution

Herpes Zoster Reactivation Singles Dermatomal Distribution

Herpes Simplex Virus Skin Sample Multinucleated Margination of Chromatin Molded Nuclei

Dermatophyte Infection Well-Demarcated, Pink-Red Patch, Peripheral Scale

Scabies Mite is burrowed in the skin. Spines

Dermatophyte Infection PAS Stain shows Dermatophyte

Dermatophyte Infection Well-Demarcated, Pink-Red Patch, Peripheral Scale

Herpes Simplex Virus HSV-2 Grouped Vesicles on an Erythematous Base