Dermoscopic features of congenital acral melanocytic naevi in children: a prospective comparative and follow-up study

Summary Background Acral naevi are a peculiar subtype of naevus with specific dermoscopic patterns. Little is known about congenital melanocytic naevi affecting acral volar skin in children. Objectives To determine the dermoscopic features of acquired and congenital acral melanocytic naevi in children and to assess their key differences in this age group. Methods This was a prospective observational controlled study conducted in two outpatient dermatology university hospitals in Nice, France. We recruited 24 children with 24 congenital acral melanocytic naevi (CAMNs) and 26 children with 33 acquired acral melanocytic naevi (AAMNs), and determined the clinical and dermoscopic features of both. Images were evaluated and compared by two dermatologists. Fourteen patients with CAMN were followed up. Results CAMNs were larger, and more asymmetrical and comma shaped than AAMNs. The parallel furrow pattern was predominant in CAMN (75%) and AAMN (79%). Globules were more frequent in CAMN (88%) than in AAMN (61%) (P = 0·026), often with a ‘pearl necklace’ distribution along skin markings. Central blue-grey pigmentation was present in 50% of CAMNs vs. 9% of AAMNs (P = 0·001). A new dermoscopic feature of central enlarged pink ridges was observed in 54% of CAMNs vs. 6% of AAMNs (P