Related Experiment Video
Updated: Jun 17, 2026
07:29
Characterization of In Vitro Differentiation of Human Primary Keratinocytes by RNA-Seq Analysis
Published on: May 16, 2020
Porokeratosis ptychotropica: a lesser-known variant
B Tallon1, G Blumental, J Bhawan
1Dermatopathology Section, Boston University School of Medicine, Boston, MA 02118-2515, USA. bentallon@gmail.com
Clinical and Experimental Dermatology
|January 9, 2010
Summary
This case study details porokeratosis ptychotropica (PP), a rare skin condition presenting as a perianal plaque. Findings suggest friction may contribute to amyloid deposition in this rare porokeratosis variant.
Area of Science:
- Dermatology
- Histopathology
Background:
- Porokeratosis ptychotropica (PP) is a rare variant of porokeratosis.
- Understanding its clinical and histological features is crucial for diagnosis.
Observation:
- A case of PP presented with a circumferential perianal plaque.
- Histopathology revealed multiple cornoid lamellae and underlying dermal amyloid deposition.
Findings:
- Amyloid deposition was localized to the biopsied intertriginous area.
- This finding suggests friction may play a role in amyloid deposition in PP.
- Literature review indicates a poor response to existing treatments for PP.
Implications:
- Highlights the potential role of friction in the pathogenesis of cutaneous amyloidosis in PP.
- Underscores the diagnostic significance of characteristic histological findings.
- Emphasizes the therapeutic challenges associated with porokeratosis ptychotropica.
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