A newborn infant with pachonychia congenita had only color changes of the nails, which were normally shaped, at birth.
The nail shape changed by pinching inward of the lateral edges and distal pointing upward and outward. The complete deformity had developed by the age of 3½ months. Its progressive development is described.
In pachonychia there is hyperkeratosis and hypertrophy of the ventral nail which normally is absent or up to one third as thick as the hard nail.
Abnormalities are demonstrated in the nail root, including dyskeratosis with the presence of a granular layer.
An attempt is made to explain the pathogenesis of the nail deformity. Evidence is presented suggesting that congenital misalignment of the nail occurs.
JOSEPH HL. Pachonychia Congenita. Arch Dermatol. 1964;90(6):594–603. doi:10.1001/archderm.1964.01600060060011
Coronavirus Resource Center
Customize your JAMA Network experience by selecting one or more topics from the list below.