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 Jadassohn–Lewandowsky syndrome and the men behind this disease
