The statements listed below are best associated with which of the figures: (a) This is a condition of autosomaldominant inheritance affecting all nails. (b) This is a condition of autosomal-dominant inheritance affecting only one or two nails. (c) This is not a hereditary condition and affects all nails.
Denouement and Discussion
(a) Pachyonychia congenita is a rare genodermatosis of autosomal-dominant inheritance with a high degree of penetrance and variable phenotypic expression. This disorder, first described by Jadassohn and Lewandowsky in 1906, has also been referred to as Jadassohn-Lewandowsky syndrome. The onychodystrophy typically appears within the fitst 6 months of life, and may be present at birth. It is characterized by hypertrophy and distal subungal hyperkeratosis of all nails. Secondary complications include nail shedding, cheronic paronychial infections, and increased susceptibility to local traumatic injuries. The only effective treatment of the nail dystrophy has been surgical removal of the entire nail.