Several factors for osteomyelitis relapse, including osteomyelitis extending for more than 3 months, bone exposure, and treatment other than surgical debridement with muscular flap, were identified as a result of results published in BMC Infectious Diseases.
The researchers evaluated 116 patients with osteomyelitis who were followed for ≥1 year after hospital discharge. The mean age of included patients was 53 years, 74.1% were men, and mean follow-up was 67.1 months. The most common bone and bacteria involved in the cases were the tibia (62.1%) and Staphylococcal aureus (58.5%), respectively.
Of this patient group, 46 underwent bone debridement, 61 underwent debridement with flap coverage, and 9 received antimicrobial therapy only. Relapse occurred in 26 patients at an average of 11.2 months after discharge. Univariate analysis indicated that duration of osteomyelitis longer than 3 months (P =.025), number of severity factors (P =.02), and absence of surgery (P =.004) were associated with osteomyelitis relapse. Using a Cox regression analysis, duration longer than 3 months (P =.012), bone exposure (P =.0003), and type of surgery (P <.0001) were associated with relapse. When looking at surgical modalities, bone debridement with muscle flap was associated with better outcomes than either no surgery (P <.0001) or debridement only (P =.004).
Study investigators noted several study limitations related to retrospective studies, a reduced sample size to analyze subgroups, and the long inclusion period. Although they acknowledged that these were largely unavoidable in a single-center series, the researchers concluded, “the single-center series ensured a greater homogeneity in the evaluation and management of the patients, the very long period of follow-up ensured the detection of late relapses and, finally, the long period of recruitment did not seem to bias the results as the year of diagnosis did not have any significant influence on the outcome (P = 0.8).”
The study investigators recommended that according to their results, surgical modalities other than debridement should be considered suboptimal, and that bone exposure and infection duration will favor poorer outcomes. They also suggested further studies are required to validate the severity of the factors they identified, and to design better treatment strategies.
Garcia Del Pozo E, Collazos J, Carton JA, Camporro D, Asensi V. Factors predictive of relapse in adult bacterial osteomyelitis of long bones. BMC Infect Dis. 2018;18:635.