Nursing Assignment Sample
Q1:
Answer :Autoimmune blistering disorders of the skin are a collection of conditions with autoantibody-induced injury to structural elements of the skin and mucosa, resulting in blistering. Of these, pemphigus vulgaris (PV) and bullous pemphigoid (BP) are the most important, differing in pathophysiology, clinical presentation, and management.
Autoimmune blistering disorders (AIBDs) are a heterogeneous group of conditions with the formation of autoantibodies to structural proteins in the skin and mucosa and resulting blister formation. Of these, pemphigus vulgaris (PV) and bullous pemphigoid (BP) are the best studied with unique pathogeneses, clinical presentations, and treatment regimens. While these diseases are uncommon, they have high morbidity and potential mortality if left untreated and/or untreated for prolonged periods.
Pathophysiology: Pemphigus Vulgaris
PV is an autoantibody-mediated intraepidermal blistering disease due to autoantibodies against desmoglein-1 and desmoglein-3, which are essential constituents of desmosomes in keratinocytes. Desmosomes confer structural strength by allowing intercellular adhesion. With disruption of desmogleins by autoantibodies, acantholysis (cell detachment) results in intraepidermal blistering. The IgG autoantibodies also stimulate proteases like plasminogen activator, further enhancing keratinocyte detachment.
PV is a type II hypersensitivity disease in which autoantibodies, mostly IgG4, recognize desmoglein-1 and desmoglein-3—vital adhesion molecules of desmosomes. These desmosomal proteins are involved in the adhesion of keratinocytes in the epidermis and mucous membranes. The dysfunction of these proteins leads to acantholysis, which is the disruption of cell-to-cell adhesion, resulting in intraepidermal blister formation.
Multiple mechanisms play a role in tissue damage in PV:
Steric hindrance – Autoantibodies inhibit normal desmoglein interactions.
Protease activation – Overexpression of plasminogen activator and matrix metalloproteinases results in degradation of cell adhesion molecules.
Cell signaling alteration – Intracellular signaling pathway dysregulation induces apoptosis of keratinocytes, exacerbating acantholysis.
Bullous Pemphigoid
BP is an IgG autoantibody-mediated subepidermal blistering disease directed against BP180 (type XVII collagen) and BP230, which are components of hemidesmosomes attaching basal keratinocytes to the basement membrane. The immune assault on these proteins results in complement activation and inflammatory cell infiltration (predominantly eosinophils), with resultant dermal-epidermal separation and subepidermal blistering.
Clinical Presentation: Pemphigus Vulgaris
Flaccid blisters that easily rupture to form painful erosions.
Mucosal involvement (oral ulcers may be the initial presentation).
Positive Nikolsky sign (epidermal detachment from rubbing of skin).
Delayed healing, with the development of large erosions and secondary infection.
Bullous Pemphigoid
Tense, clear or hemorrhagic-filled bullae.
Mucosal lesions less common than in PV.
Antecedent urticarial or eczematous stage.
Negative Nikolsky sign (easy rupturing blisters are not).
Prevalent in older persons, with relapsing and remitting chronic course.
Diagnosis: Part 1
Pemphigus Foliaceus – Pemphigus similar but is desmoglein-1 limited, and there is no mucosal manifestation.
Linear IgA Dermatosis – Subepidermal blisters with IgA deposits instead of IgG.
Epidermolysis Bullosa Acquisita – IgG autoantibodies to type VII collagen; more scarring.
Erythema Multiforme & Stevens-Johnson Syndrome – Targetoid lesion blistering from drug reactions or infections.
Dermatitis Herpetiformis – Linked with celiac disease; vesicles that are itchy on extensor surfaces.
Diagnosis: Part 2
Histopathology & Immunofluorescence
PV: Intraepidermal blisters with acantholysis. Direct immunofluorescence (DIF) is positive for IgG and C3 deposits in an intercellular distribution.
BP: Eosinophilic subepidermal blistering. DIF shows linear IgG and C3 deposition at the basement membrane zone.
Serological Tests
ELISA for desmoglein-1 and desmoglein-3 antibodies (PV).
ELISA for BP180 and BP230 autoantibodies (BP).
Treatment Options:Pemphigus Vulgaris
First-line: Corticosteroids (prednisone 1–1.5 mg/kg/day).
Steroid-sparing agents:
Azathioprine
Mycophenolate mofetil
Rituximab (anti-CD20 monoclonal antibody) – now used for severe cases.
Intravenous immunoglobulin (IVIG) or plasmapheresis for refractory cases.
Bullous Pemphigoid
Topical corticosteroids (clobetasol) – preferred for localized disease.
Systemic corticosteroids (prednisone 0.5 mg/kg/day) for widespread disease.
Steroid-sparing agents:
Doxycycline (mild cases).
Methotrexate or rituximab in refractory cases.
Omalizumab (anti-IgE therapy) – novel treatment for BP.
Conclusion
Pemphigus vulgaris and bullous pemphigoid, although both autoimmune blistering disorders, possess different pathophysiological mechanisms, clinical presentations, and therapeutic strategies. PV is distinguished by intraepidermal acantholysis and flaccid blisters, while BP is characterized by subepidermal blistering with tense bullae. Histopathology, immunofluorescence, and serological tests form the basis for diagnosis. Therapy consists mainly of corticosteroids and immunosuppression, with rituximab being a prominent player in PV therapy. Targeted therapies like biologics are revolutionizing treatment paradigms for both disorders. Early recognition, appropriate diagnostic testing, and aggressive immunosuppressive therapy are crucial for disease control. The advent of targeted biologic therapies, such as rituximab and omalizumab, is transforming the management of these conditions, offering hope for better outcomes with fewer side effects.