Melanocytic nevi on the hyponychium with dermoscopic features of longitudinal brush pigmentation in children

Surface anatomy in dermatology: Part I-Clinical importance, diagnostic utility, and impact on medical management

This continuing medical education series reviews updated Delphi consensus surface anatomy terminology through the lens of common medical and procedural dermatology scenarios, helping to underscore high-yield points that can be readily integrated into clinical practice to support patient care. Part I of this series will discuss the current state of surface anatomy terminology in dermatology, outline implications of precise and consistent terminology, provide an illustrative overview of high-yield consensus terminology, highlight prominent landmarks that can aid in critical diagnoses, and relate the importance of precise terminology to medical management. Part II will draw upon consensus terminology to inform the management of cutaneous malignancies and support optimal outcomes in dermatologic procedures.

Dermatoscopic and clinical features of congenital or congenital-type nail matrix nevi: A multicenter prospective cohort study by the International Dermoscopy Society

BACKGROUND

Congenital nail matrix nevi (NMN) are difficult to diagnose because they feature clinical characteristics suggestive of adult subungual melanoma. Nail matrix biopsy is difficult to perform, especially in children.

OBJECTIVE

To describe the initial clinical and dermatoscopic features of NMN appearing at birth (congenital) or after birth but before the age of 5 years (congenital-type).

METHODS

We conducted a prospective, international, and consecutive data collection in 102 hospitals or private medical offices across 30 countries from 2009 to 2019.

RESULTS

There were 69 congenital and 161 congenital-type NMNs. Congenital and congenital-type NMN predominantly displayed an irregular pattern of longitudinal microlines (n = 146, 64%), reminiscent of subungual melanoma in adults. The distal fibrillar ("brush-like") pattern, present in 63 patients (27.8%), was more frequently encountered in congenital NMN than in congenital-type NMN (P = .012). Moreover, congenital NMN more frequently displayed a periungual pigmentation (P = .029) and Hutchinson's sign (P = .027) than did congenital-type NMN.

LIMITATIONS

Lack of systematic biopsy-proven diagnosis and heterogeneity of clinical and dermatoscopic photographs.

CONCLUSION

Congenital and congenital-type NMN showed worrisome clinical and dermatoscopic features similar to those observed in adulthood subungual melanoma. The distal fibrillar ("brush-like") pattern is a suggestive feature of congenital and congenital-type NMN.