Transient neonatal hyperpigmentation of the proximal nail fold in a Chinese infant: a case report.

Cutaneous alterations are common in neonates and usually occur in the first few days of life. Most of these are transient and benign, appearing as physiological responses to birth. Skin pigmentation disorders are considered transitory dermatoses of newborn infants. Nail pigmentation manifests as asymptomatic brown to bluish-black skin pigmentation over the fingers and toes in newborns. Hyperpigmentation of the distal phalanx of both hands and feet is commonly found in dark-skinned newborns, but it is rare in fair-skinned newborns and East Asian populations. We herein describe a Chinese infant with transient neonatal hyperpigmentation of the proximal nail fold.