Timely Surgery and Time to Culture Positivity: Prognostic Indicators in Staphylococcus-related Pyogenic Spondylodiscitis.

Abstract

Time to culture positivity (TTP) is a recognized surrogate for bacterial load and virulence in bloodstream infections; however, its prognostic utility using intraoperative tissue cultures in pyogenic spondylodiscitis remains undefined. Furthermore, the optimal surgical window in this context remains to be established. This study aims to determine the prognostic value of TTP and identify the optimal surgical timing in patients with de novo Staphylococcus-related pyogenic spondylodiscitis. Retrospective cohort study in a tertiary referral medical center. Forty-eight consecutive patients treated surgically for de novo Staphylococcus-related pyogenic spondylodiscitis between 2015 and 2021 (mean age: 61.8 years). The primary outcomes were overall survival (OS) and recurrence-free survival (RFS). Recurrence was defined as the need for revision surgery due to recurrent spondylodiscitis following the completion of antibiotic therapy. Univariate and multivariate Cox regression analyses were performed to identify predictors of primary outcomes. Optimal cut-off values for TTP and surgical timing were analyzed to maximize prognostic discrimination. The 1-year OS and RFS were 76% and 58%, respectively. A prolonged TTP (≥ 60 hours) and timely surgery (≤ 14 days) were associated with improved outcomes, demonstrating significantly better OS (HR 0.18, p = 0.003; HR 0.22, p = 0.019) and RFS (HR 0.27, p = 0.003; HR 0.35, p = 0.024). In this cohort, timely surgery (within 14 days) and prolonged TTP (more than 60 hours) were associated with improved overall and recurrence-free survival. These findings suggest that integrating specific surgical timeframes and bacterial growth characteristics may enhance risk stratification and guide management in Staphylococcus-related pyogenic spondylodiscitis.