iatroX Rounds #25
The clues
- 1
An 82-year-old woman presents with a widespread, intensely itchy rash that has been progressively worsening over the past month.
- 2
She describes a prodromal phase of several months involving severe generalized pruritus and erythematous, urticarial-like patches.
- 3
Her past medical history is significant for Parkinson's disease and a previous ischaemic stroke.
- 4
On examination, there are multiple large, tense, fluid-filled bullae on the trunk and limbs; the Nikolsky sign is negative.
- 5
Blood tests reveal a marked peripheral eosinophilia, and a skin biopsy confirms the presence of a subepidermal blister.
- 6
Direct immunofluorescence of perilesional skin demonstrates a continuous linear band of IgG and C3 along the dermo-epidermal junction.
<p><strong>Bullous pemphigoid</strong> is a chronic, autoimmune subepidermal blistering disorder that primarily affects the elderly. It is characterized by the presence of autoantibodies against hemidesmosomal proteins, and it is frequently associated with neurological conditions such as <strong>Parkinson's disease</strong> and dementia.</p>
- Intense prodromal pruritus
- Large, tense bullae on an erythematous base
- Subepidermal split on histology
- Linear IgG and C3 at the basement membrane
for education and entertainment. not medical advice.