A 65 year old male presented with following skin lesions on flexural areas of the skin.What is the most probable diagnosis?
A. Pemphigus Vulgaris
B. Dermatitis Herpetiformis
C. Bullous Pemphigoid
D. Linear IgA disease
Ans:C. Bullous Pemphigoid.
- It is a chronic, autoimmune, subepidermal, blistering skin disease that rarely involves mucous membranes.
- Bullous pemphigoid primarily affects elderly individuals in the fifth through seventh decades of life, with an average age at onset of 65 years. Bullous pemphigoid of childhood onset has been reported in the literature,which may be more self-limited.
- Bullous pemphigoid may present with several distinct clinical presentations, as follows:
- Generalized bullous form: Tense bullae arise on any part of the skin surface, with a predilection for the flexural areas of the skin
- Vesicular form: Groups of small, tense blisters, often on an urticarial or erythematous base
- Vegetative form: Very uncommon, with vegetating plaques in intertriginous areas of the skin, such as the axillae, neck, groin, and inframammary areas
- Generalized erythroderma form: This rare presentation characterised byexfoliative erythroderma
- Urticarial form: Some patients with bullous pemphigoid initially present with persistent urticarial lesions that subsequently convert to bullous eruptions; in some patients, urticarial lesions are the sole manifestations of the disease
- Nodular form: This rare form, termed pemphigoid nodularis, blisters arising on normal-appearing or nodular lesional skin
- Acral form: In childhood-onset bullous pemphigoid associated with vaccination, the bullous lesions predominantly affect the palms, soles, and face
- Infant form: In infants affected by bullous pemphigoid, the blisters tend to occur frequently on the palms, soles, and face, affecting the genital areas rarely; 60% of these infant patients have generalized blisters .
- Nikolsky’s sign is negative unlike pemphigus vulgaris where it is positive.
- Histopathologic analysis: From the edge of a blister; the histopathologic examination demonstrates a subepidermal blister; the inflammatory infiltrate is typically polymorphous, with an eosinophil predominance; mast cells and basophils may be prominent early in the disease course
- Direct immunofluorescence (DIF) studies: Performed on normal-appearing, perilesional skin .
- Demonstrates immunoglobulin G (IgG) and complement C3 deposition in a linear band at the dermal-epidermal junction
- Indirect immunofluorescence (IDIF) studies: Performed on the patient’s serum, if the DIF result is positive .
- Shows the presence of circulating IgG autoantibodies in the patient’s serum that target the skin basement membrane component.
- The most commonly used medications for bullous pemphigoid are anti-inflammatory agents (eg, corticosteroids, tetracyclines, dapsone) and immunosuppressants (eg, azathioprine, methotrexate, mycophenolate mofetil, cyclophosphamide)