Title:Acanthosis Nigricans: An Updated Review
Volume: 19
Issue: 1
Author(s): Alexander K.C. Leung*, Joseph M. Lam, Benjamin Barankin, Kin Fon Leong and Kam Lun Hon
Affiliation:
- Department of Pediatrics, The University of Calgary, Alberta Children’s Hospital, Calgary, Alberta, Canada
Keywords:
Acanthosis nigricans, hyperpigmentation, obesity, insulin resistance, retinoids, vitamin D analogs, chemical peels, keratolytics.
Abstract:
Background: Early recognition of acanthosis nigricans is important because acanthosis
nigricans can be a cutaneous manifestation of a variety of systemic disorders and, rarely, as a sign
of internal malignancy.
Objective: The purpose of this article is to familiarize pediatricians with the clinical manifestations,
evaluation, diagnosis, and management of acanthosis nigricans.
Methods: A search was conducted in November 2021in PubMed Clinical Queries using the key
term "acanthosis nigricans". The search strategy included all clinical trials, observational studies,
and reviews published within the past 10 years. Only papers published in the English literature were
included in this review. The information retrieved from the above search was used in the compilation
of the present article.
Results: Acanthosis nigricans is characterized by symmetric, hyperpigmented, and velvety plaques
with ill-defined borders, typically involving intertriginous areas. Obesity is the most common cause
of acanthosis nigricans which is increasingly observed in obese children and adolescents and can
serve as a cutaneous marker of insulin resistance. Early recognition of acanthosis nigricans is important
because acanthosis nigricans can also be a cutaneous manifestation of a variety of systemic
disorders and, rarely, as a sign of internal malignancy. This may consist of weight reduction, discontinuation
of causative drugs, treatment of underlying endocrinopathy, or treatment of an underlying
malignancy. For patients with isolated acanthosis nigricans and for those whose underlying
cause is not amenable to treatment, treatment of the lesion may be considered for cosmetic reasons.
Topical retinoids, vitamin D analogs, chemical peels, and other keratolytics are often used for the
treatment of localized lesions. Seldom, systemic therapy such as oral retinoids may be considered
for extensive or generalized acanthosis nigricans and acanthosis nigricans unresponsive to topical
therapy. Other uncommon treatment modalities include dermabrasion, laser therapy, and surgical
removal.
Conclusion: Although acanthosis nigricans is treatable, a complete cure is difficult to achieve. The
underlying cause should be treated, if possible, to resolve and prevent the recurrence of acanthosis
nigricans. The diagnosis is mainly clinical, based on the characteristic appearance (symmetrically
distributed, hyperpigmented, velvety, papillomatous, hyperkeratotic plaques with ill-defined borders)
and the typical sites (intertriginous areas, flexural area, and skin folds) of the lesions. The diagnosis
might be difficult for lesions that have atypical morphology or are in an unusual location.
Clinicians should be familiar with the clinical signs, evaluation, diagnosis, and therapy of acanthosis
nigricans because of the link between it and underlying diseases.
