To our knowledge, few cases of relapse in adulthood are described in the literature except in patients with sickle cell disease and the epidemiological, clinical, laboratory, radiological features and the management of osteomyelitis relapsing in adulthood are not described. The aim of this retrospective multicentric cohort study : in France is to describe the epidemiological, clinical, laboratory, and radiological features and the management of adult patients who experienced a relapse between 2003-2015 of an acute hematogenous osteomyelitis acquired in the childhood (description of characterization of the period between the first episode of osteomyelitis and the second episode, description of signs of relapse and description of treatments used in the relapse). The data are analysed with non-comparative descriptive statistics.

Inclusion Criteria:

• Adult patients (≥ 18 years) who presented a relapse between 2003-2015 of a hematogenous osteomyelitis acquired in childhood.
• the time limit between the 2 episodes must be at least 2 years
• antecedent of osteomyelitis before 16 years

Exclusion Criteria:

• inability to give the information to the patient
• patients opposed to the use of their data

Adult patients (≥ 18 years) who presented a relapse between 2003-2015 of a hematogenous osteomyelitis acquired in childhood.