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Related Experiment Video

Updated: Jul 3, 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

Granular parakeratosis.

José M Martín¹, Isabel Pinazo, Inmaculada Molina

¹Departments of Dermatology and Pathology, Hospital Clínico Universitario, Valencia, Spain. jmmart@eresmas.com

International Journal of Dermatology

|July 11, 2008

Summary

A pruritic axillary eruption in a 62-year-old woman was diagnosed as granular parakeratosis. Treatment with topical steroids and discontinuation of antiperspirants led to complete resolution.

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Area of Science:

Dermatology
Histopathology

Background:

A 62-year-old woman presented with a month-long history of itchy, bumpy rash in her armpits.
The rash appeared after waxing and changing antiperspirant.

Observation:

Physical examination revealed erythematous and brownish hyperkeratotic papules and plaques in both axillae.
No other skin folds were affected, and the patient had no systemic symptoms.

Findings:

Histological analysis of a skin biopsy showed a thickened stratum corneum with persistent nuclei and basophilic granules, consistent with granular parakeratosis.
Hypergranulosis was noted in some areas.

Implications:

Granular parakeratosis is a distinct histopathological finding that can manifest as an axillary eruption.
The condition appears to be triggered by external factors such as hair removal and antiperspirant use.
Treatment with topical corticosteroids and discontinuation of inciting agents resulted in complete resolution of the cutaneous lesions.