Pachydermoperiostosis (or primary hypertrophic osteoarthropathy) is a rare genetic disease that usually begins in childhood or adolescence, is characterized by certain clinical signs (pachydermia, periostosis, drum sticks) that gradually progress over many years until the disease stabilizes. Currently, there are 2 genes in which mutations are associated with the development of pachydermoperiostosis - HPGD and SLCO2A1. The functions of these genes are not fully understood, but their influence on the metabolism of prostaglandin E2 is known.