Papillon-Lefevre syndrome (PLS) is a rare ectodermal dysplasia characterized by palmoplantar keratoderma associated with early-onset periodontitis. The disease is Monarch Disease Ontology term MONDO_0009490 (Papillon-Lefevre disease). Also known as: PLS, Papillon Lefevre syndrome, Papillon Lefèvre Syndrome, Papillon-Lefvre syndrome, keratosis palmoplantar-periodontopathy syndrome.