Vesiculobullous disease Notes

NOTES NOTES VESICULOBULLOUS DISEASES GENERALLY, WHAT ARE THEY? PATHOLOGY & CAUSES ▪ Chronic skin blistering diseases; associated with underlying autoimmune, genetic pathology ▪ Destruction/malfunction of structural, anchoring proteins of skin SIGNS & SYMPTOMS ▪ Skin blistering ▪ Mucosal erosions pruritus DIAGNOSIS LAB RESULTS ▪ Skin biopsy ▪ Immunofluorescence testing TREATMENT MEDICATIONS ▪ Corticosteroids OTHER INTERVENTIONS ▪ Lifestyle modifications BULLOUS PEMPHIGOID osms.it/bullous-pemphigoid PATHOLOGY & CAUSES ▪ Autoimmune skin disease; bubble-like blisters ▫ Bulla- = blister, pemphig- = bubble, oid= similar ▪ Chronic, relapsing, remitting, autoimmune subepithelial blistering disease ▫ Epithelial lesions (unlike pemphigus vulgaris) ▫ Can affect mucous membranes ▪ Presents with cutaneous bullae, mucosal erosions ▪ Rare disease, most common autoimmune blistering disorder 64 OSMOSIS.ORG CAUSES ▪ Autoantibodies against hemidesmosomal proteins ▫ Bullous pemphigoid antigen 2 (BPAg2) ▫ Collagen type XVII ▪ Autoantibodies may develop in response to certain drugs/infections ▪ Autoantibody activation → abnormal IgG/complement deposition in basement membrane zone → separation of dermis, epidermis → inflammatory reaction → formation of blisters, inflammatory mucosal erosions RISK FACTORS ▪ More common in individuals > 60 years

Chapter 10 Vesiculobullous Diseases SIGNS & SYMPTOMS ▪ Trunk, skin folds, extremities most affected ▪ May exhibit prodromal phase ▫ Pruritic papular lesions, resemble eczema ▪ Oral, ocular mucositis ▪ Blisters with inflammatory/noninflammatory base ▪ Unlike pemphigus vulgaris, bullae tense, difficult to rupture → negative Nikolsky sign ▪ After rupture, scarring uncommon TREATMENT MEDICATIONS ▪ Topical/systemic corticosteroids ▫ Decrease blister formation, promote blister healing, improve quality of life DIAGNOSIS LAB RESULTS ▪ Histopathological studies (confirm) ▫ Skin biopsies, immunofluorescent staining techniques ▪ Complete blood count (CBC) ▫ Eosinophilia ▪ ↑ IgG antibodies Figure 10.1 The histological appearance of the skin in a case of bullous pemphigoid. In contrast to pemphigus vulgaris, the bullae are subepithelial. The bullae contain an infiltrate of eosinophils. EPIDERMOLYSIS BULLOSA osms.it/epidermolysis-bullosa PATHOLOGY & CAUSES ▪ Skin breakdown → blisters ▫ Epidermo- = skin, lysis- = breakdown, bullosa- = blistering ▪ Rare condition, inherited group of disorders; blisters, erosions after minor skin trauma due to fragility of epithelial tissue ▪ May also affect mucous membranes, nails CAUSES ▪ Mutations in structural proteins of skin responsible for tissue integrity ▫ Keratin, desmosomes, cell junctions, intermediate filaments, etc. ▫ Presence of some or all → determine disease severity, clinical presentation RISK FACTORS ▪ Genetic inheritance SIGNS & SYMPTOMS ▪ Localized/systemic ▪ Skin blistering following minor trauma/ friction ▪ Nail dystrophy, loss (common) ▪ Oral lesions OSMOSIS.ORG 65

DIAGNOSIS LAB RESULTS ▪ Skin biopsy ▪ Immunofluorescence testing OTHER DIAGNOSTICS ▪ Family history TREATMENT ▪ No specific therapy OTHER INTERVENTIONS Figure 10.2 The hands of an individual with epidermolysis bullosa. Numerous consecutive bullae have caused scarring and induration of the skin, leading to contractures. ▪ Symptomatic care, wound care, infection prophylaxis, pain management PEMPHIGUS VULGARIS osms.it/pemphigus-vulgaris PATHOLOGY & CAUSES ▪ Autoimmune, life-threatening blistering disorders of skin, mucous membranes ▪ Epithelial lesions ▫ Unlike bullous pemphigoid, which presents with subepithelial lesions ▪ Acantholysis: defining mechanism (acanthus- = thorny, lysis- = breakdown) ▫ Impaired adhesion between cells in spinous layer of epidermis CAUSES ▪ Autoantibodies against desmoglein ▪ Autoantibody activation → attack of adhesion molecules → breakdown of intercellular adhesion → inflammatory reaction → blister formation RISK FACTORS ▪ Adults ▪ Jewish people of Middle Eastern origin 66 OSMOSIS.ORG SIGNS & SYMPTOMS ▪ Oral mucosa (most common); can affect all mucosal surfaces ▪ Nikolsky sign → blister ruptures with pressure/friction ▫ Unlike bullous pemphigoid, where blisters difficult to rupture ▪ Easily-eroding painful blisters over erythematous skin ▪ No pruritus DIAGNOSIS LAB RESULTS ▪ Skin biopsy ▪ Immunofluorescent staining ▪ Serum antibodies

Chapter 10 Vesiculobullous Diseases TREATMENT MEDICATIONS ▪ Systemic steroids ▪ Immunosuppressive agents Figure 10.3 A histological section of the skin in a case of pemphigus vulgaris. There is intraepidermal bulla formation in the superficial epidermis and characteristic tombstoning of the dermoepidermal junction. OSMOSIS.ORG 67