obsolete_acanthosis nigricans true true Sirarat Sarntivijai MedDRA:10000350 3.88.0 Keratosis nigricans Replaced by Mondo term MONDO_0007035, with which this term was previously merged. Use: http://purl.obolibrary.org/obo/MONDO_0007035 Wikipedia:Acanthosis_nigricans DOID:3138 http://purl.obolibrary.org/obo/MONDO_0007035 ICD10:L83 keratosis nigricans AN a brown to black, poorly defined, velvety hyperpigmentation of the skin. It is usually found in body folds, such as the posterior and lateral folds of the neck, the armpits, groin, navel, forehead, and other areas.