Multicentre cohort study reveals genetic and clinical insights into linear and whorled nevoid hypermelanosis, highlighting extracutaneous effects.
Key Points
This study aims to refine the clinical understanding of linear and whorled nevoid hypermelanosis and explore its genetic associations and extracutaneous manifestations.
Conducted a multicentre retrospective cohort analysis across seven dermatology departments.
Screened photographic archives for cases of hyperpigmentation and mosaicism.
Reviewed medical records and clinical photographs based on standardized classifications.
Performed genetic testing on lesional skin and/or blood samples if available.
Identified 33 patients with a median age at onset under 1 year and a median diagnostic delay of 2 years.
Extracutaneous manifestations were found in 61% of patients, predominantly neurological (52%).
30% of patients with genetic testing had identifiable abnormalities linked to their condition—chromosomal mosaicism or pathogenic variants in KITLG.