Inclusion Criteria:  Subject aged 18 years and over at the time of diagnosis Osteoarticular infection (septic arthritis, spondylodiscitis), by a bacterium or a fungus, proven by a bacteriological sample in situ or in the blood by positive blood culture (with an unequivocal clinical, biological and imaging feature), Diagnosed between 01/01/2010 and 12/31/2020 (11 years) Hospitalization in the rheumatology department of CH René Dubos, Pontoise  Exclusion Criteria:  Bacterial infection due to the following germs: mycobacteria, brucella, Borrelia Early infection on joint prosthesis Peripheral osteomyelitis Osteoarticular infection without bacteriological proof