Noonan syndrome-like disorder: Case report and review of the literature.

Abstract

Of patients with a Noonan syndrome phenotype, only about 1% are found to be related to pathological variants in CBL, also known as Noonan syndrome-like disorder (NSLD). We present a case of a 4-year-old boy diagnosed with NSLD, presenting with multiple melanocytic nevi and superficial neurofibromas. A literature review identified common cutaneous findings of NSLD, for example, café-au-lait macules (22%), juvenile xanthogranuloma (16%), and thin hair (10%). As there are no documented cases of neurofibromas associated with NSLD, and only a single report of multiple melanocytic nevi, inclusion of these features in the phenotype may be warranted and mitigate the necessity for future biopsies in other children.