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Related Experiment Video

Updated: Mar 6, 2026

Characterization of In Vitro Differentiation of Human Primary Keratinocytes by RNA-Seq Analysis

Characterization of In Vitro Differentiation of Human Primary Keratinocytes by RNA-Seq Analysis

Published on: May 16, 2020

Porokeratosis ptychotropica.

Ana Carolina Franco Tebet¹, Tatiana Gandolfi de Oliveira¹, Anna Rita Ferrante Mitidieri de Oliveira¹

¹Universidade de Santo Amaro (UNISA) - Santo Amaro (SP), Brazil.

Anais Brasileiros De Dermatologia

|March 17, 2017

Summary

Porokeratosis ptychotropica is a rare skin condition presenting as verrucous plaques on the buttocks. This report details an unusual single-plaque manifestation, the first documented in Brazil.

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Published on: December 22, 2017

Area of Science:

Dermatology
Rare Skin Diseases

Background:

Porokeratosis is a group of skin disorders characterized by annular plaques and cornoid lamellae.
Several clinical variants exist, with Porokeratosis ptychotropica being rare and less understood.

Observation:

Porokeratosis ptychotropica typically presents as verrucous plaques on the buttocks, often resembling psoriasis.
Itching is a common symptom, and involvement may extend to extremities.

Findings:

This case report describes an unusual single-plaque manifestation of Porokeratosis ptychotropica.
This represents the first documented case of this variant in the Brazilian medical literature.

Implications:

Highlights the diverse clinical presentations of rare dermatological conditions.
Emphasizes the importance of recognizing unusual variants of porokeratosis for accurate diagnosis and management.
Contributes to the limited global literature on Porokeratosis ptychotropica, particularly its atypical forms.