Onychoscopic Alterations in Newborns with Early Congenital Syphilis: A Single-Center Cross-Sectional Study of 10 Cases.

Abstract

Introduction: Early congenital syphilis (ECS) is a vertically transmitted infection that remains difficult to diagnose in the neonatal period, as many newborns are asymptomatic at birth. Although mucocutaneous manifestations are well recognized, nail involvement has been rarely described.

Methods: We conducted a prospective, single-center study including neonates with ECS fulfilling scenario 1 or 2 criteria established by the Centers for Disease Control and Prevention and the American Academy of Pediatrics. Ten neonates admitted to the neonatal intensive care unit between April and July 2025 were enrolled. Systematic onychoscopy (10×) of all 20 nails was performed. Findings were analyzed according to serum Venereal Disease Research Laboratory (VDRL) titers, comparing group 1 (<1:128) and group 2 (≥1:128 or prozone phenomenon).

Results: The most frequent abnormalities were onycholysis and onychoschizia (100%), herringbone nail pattern (80%), and periungual scaling (90%). Mega lunula and anonychia (40% each) were significantly associated with VDRL titers ≥1:128 and/or prozone phenomenon (p < 0.05).

Conclusion: Mega lunula and anonychia may serve as clinical markers of ECS in neonates with high VDRL titers, supporting onychoscopy as a complementary diagnostic tool.