Diagnostic, clinical management, and outcome of bone flap-related osteomyelitis after cranioplasty

Objectives: We aimed to describe diagnostic, management, and outcome of bone flap-related osteomyelitis after cranioplasty. Methods: Patients followed up in our tertiary care hospital for bone flap-related osteomyelitis after cranioplasty were included in a retrospective cohort (2008-2021). Determinants of treatment failure were assessed using logistic regression and Kaplan-Meier curves analysis. Results: The 144 included patients (81 [56.3%] males; median age 53.4 [interquartile range [IQR], 42.662.5] years) mostly presented wound abnormalities (n = 115, 79.9%). All infections were documented, the main pathogens being Staphylococcus aureus (n = 64, 44.4%), Cutibacteum acnes (n = 57, 39.6%), gram-negative bacilli (n = 40, 27.8%) and/or non-aureus staphylococci (n = 34, 23.6%). Surgery was performed in 140 (97.2%) cases, for bone flap removal (n = 102, 72.9%) or debridement with flap retention (n = 31, 22.1%), along with 12.7 (IQR, 8.0-14.0) weeks of antimicrobial therapy. After a follow-up of 117.1 (IQR, 62.5-235.5) weeks, 37 (26.1%) failures were observed: 16 (43.2%) infection persistence, three (8.1%) relapses, 22 (59.5%) superinfections and/or two (1.7%) infection-related deaths. Excluding superinfections, determinants of the 19 (13.4%) specific failures were an index craniectomy for brain tumor (odds ratio = 4.038, P = 0.033) and curettage of bone edges (odds ratio = 0.342, P = 0.048). Conclusion: Post-craniectomy bone flap osteomyelitis are difficult-to-treat infection, necessitating prolonged antimicrobial therapy with appropriate surgical debridement, and advocating for multidisciplinary management in dedicated reference centers. (c) 2023 The Authors. Published by Elsevier Ltd on behalf of International Society for Infectious Diseases. This is an open access article under the CC BY-NC-ND license ( http://creativecommons.org/licenses/by-nc-nd/4.0/ )