Home
Chapter Home
Jobs
Conferences
Fellowships
Books
Advertisement
Skin-nontumor
Other dermatoses
Acanthosis nigricans
Reviewer: Mowafak Hamodat MB.CH.B, MSc., FRCPC (see Reviewers
page)
Revised: 26 August 2011, last major update July 2011
Copyright: (c) 2002-2011, PathologyOutlines.com, Inc.
Definition
=========================================================================
● Brown, velvety and verrucous plaques in axillae, back of neck and other skin folds, associated with visceral malignancies, endocrine diseases and congenital disorders
Clinical features
=========================================================================
● Cutaneous manifestation of a diverse group of diseases
● May occur as inherited disorder, with Down's syndrome or after ingestion of drugs
● 80% are "benign" type, either autosomal dominant or associated with tissue resistance to insulin, including diabetes, obesity and Cushing’s disease
● 20% are associated with GI or other internal malignancies
● Usually age 40+ years
Clinical description
=========================================================================
● Brown, velvety, and verrucous plaques in axillae, back of neck and other skin folds
● Oral mucosa (lips and tongue) affected in 25% of cases; rare involvement of esophagus
● Hyperkeratotic lesions may develop on the palms, soles and knuckles
Clinical images
=========================================================================
Various images
Micro description
=========================================================================
● Orthokeratotic hyperkeratosis (not actually acanthosis) and papillomatosis of stratum spinosum
● Hyperpigmentation of basal cell layer, but no melanocytic hyperplasia
● Usually no dermal inflammation
Micro images
=========================================================================
Various images
Differential diagnosis
=========================================================================
● Epidermal nevus
● Seborrheic keratosis
● Oral lesions may resemble Condyloma accuminta
Additional references
=========================================================================
End of Skin-nontumor > Other dermatoses > Acanthosis nigricans
This information is intended for physicians and related personnel, who understand that medical information is often imperfect, and must be interpreted in the context of a patient's clinical data using reasonable medical judgment. This website should not be used as a substitute for the advice of a licensed physician.
All information on this website is protected by copyright of PathologyOutlines.com, Inc. Information from third parties may also be protected by copyright. Please contact us at copyrightPathOut@gmail.com
with any questions (click here for other
contact information).