Josef Jadassohn (1863-1936) and his assistant, Felix Lewandowsky (1879-1921), were eminent German dermatologists who had several dermatology conditions linked eponymously. One such condition is Jadassohn-Lewandowsky syndrome, which is a type of pachyonychia congenita - a disease that is characterized by severe thickening of the nail due to massive nail hyperkeratosis. This report describes Jada...

Naevus sébacé de Jadassohn est un hamartome cutanée congénitale avec une incidence estimée de 0,3% chez les nouveaunés. Il est généralement situé sur la tête et du cou. Il s'agit le plus souvent d'une lésion solitaire ovalaire de petite taille 2 a 3 cm. Elle apparait à la naissance sous forme de plaque rosée granitée du cuir chevelu ou du front. A la puberté, la lésion devient mamelonnée et pig...

Nevus sebaceous of Jadassohn is a congenital hamartoma that usually affects the scalp and face. Several benign or malignant neoplasias may develop in the lesion and the most common are trichoblastoma, syringocystadenoma papilliferum, and basal cell carcinoma. Trichilemmoma is a benign solid tumor originating from external sheath cells of pilosebaceous follicles. When it is characterized by a ce...

The sebaceous nevus, a congenital sk in disease, was first described in 1895 by Jadassohn [1] and later became known as the organoid nevus syndrome within the grouping of the phacomatoses [2]. In 1957 , Schimmelpenning [3] described its assoc iation with central nervous system, skeletal, and eye lesions. In 1962, Feuerstein and Mims [4] reported a case with epi lepsy and mental retardation . In...

Figure 1. Hairless scalp vertex lesion present since birth that has been slowly enlarging.