[Genetic basis of chronic nonbacterial osteomyelitis].

Chronic nonbacterial osteomyelitis (CNO) and SAPHO (syndrome of synovitis, acne, pustulosis, hyperostosis, osteitis) syndrome are rare autoinflammatory diseases characterized by inflammatory manifestations of the skeletal system often accompanied by skin and less frequently intestinal and pulmonary involvement. Despite familial clustering being observed, the prevailing genetic causes are yet to be fully understood. This review article summarizes the current evidence on the genetic background of CNO. Rare functional variants in LPIN2, IL1RN, and FBLIM1 have been described in isolated individuals, suggesting monogenic inheritance, while more common susceptibility factors such as the HLA-B*27 allele and P2RX7 variants indicate a more complex mode of inheritance. Genetic overlaps with familial Mediterranean fever in the Turkish population and partial response of these CNO patients to colchicine could indicate a shared pathogenetic spectrum. In conclusion, the genetic architecture of CNO appears heterogeneous, encompassing susceptibility factors and, pathogenic variants with potential therapeutic implications. Lack of many solved cases underlines the necessity to perform further genetic research.