ImmunoDeficiency Resource (IDR)

Defects in CTSC are a cause of Papillon-Lefevre syndrome. Cathepsin C (CTSC) is a lysosomal protease known to activate enzymes that are vital to the body's defenses. Onset of disease occurs between the first and fifth years of life. PLS is mainly detected by dentists because of the severe periodontitis that affects patients. Both the deciduous and permanent dentitions are affected, resulting in premature tooth loss. Palmoplantar keratosis, varying from mild psoriasiform scaly skin to overt hyperkeratosis, typically develops within the first three years of life. Keratosis also affects other sites such as elbows and knees. A variant, Haim-Munk syndrome, features, in addition to PPK and periodontitis, arachnodactyly, acroosteolysis, and onychogryphosis.