Oral Versus Standard Antimicrobial Treatment for Pyogenic Native Vertebral Osteomyelitis: A Single-Center, Retrospective, Propensity Score-Balanced Analysis

Lorenzo Marconi; Sara Tedeschi; Eleonora Zamparini; Silvia Terzi; Nicolò Rossi; Luca Boriani; Filippo Trapani; Maddalena Giannella; Damiano Alfio Ruinato; Elisa Marchionni; Alessandro Gasbarrini; Pierluigi Viale

doi:10.1093/ofid/ofac366

Oral Versus Standard Antimicrobial Treatment for Pyogenic Native Vertebral Osteomyelitis: A Single-Center, Retrospective, Propensity Score-Balanced Analysis

Open Forum Infect Dis. 2022 Jul 27;9(8):ofac366. doi: 10.1093/ofid/ofac366. eCollection 2022 Aug.

Affiliations

¹ Infectious Disease Unit, IRCCS Azienda Ospedaliero Universitaria di Bologna, Bologna, Italy.
² Department of Oncological and Degenerative Spine Surgery, IRCCS Istituto Ortopedico Rizzoli, Bologna, Italy.
³ School of Medicine, University of Bologna, Bologna, Italy.

Abstract

Background: Interest in shorter antimicrobial regimens and oral treatment for osteoarticular infections is growing. The aim of this study is to assess whether there is an association between the administration of an entirely oral antibiotic therapy (OT) and the clinical outcome of native vertebral osteomyelitis (NVOs).

Methods: We conducted a single-center, retrospective, observational study on consecutive patients with pyogenic NVOs over a 10-year period (2008-2018). We performed multivariate logistic regression analysis to identify risk factors for clinical failure, both in the whole population and in subgroups. The impact of OT versus standard treatment (intravenous induction followed by oral treatment whenever possible) was assessed in patients with a non-multidrug-resistant microorganism (MDRO) etiology, and the impact of a rifampin-containing regimen was assessed in patients affected by NVOs caused by staphylococci or of unknown etiology.

Results: The study population included 249 patients, and 33 (13.3%) experienced clinical failure; the OT group consisted of 54 patients (21.7%). Multivariate regression analysis of the whole population selected Charlson comorbidity index (adjusted odds ratio [aOR], 1.291; 95% confidence interval [CI], 1.114-1.497; P = .001) and MDRO etiology (aOR, 3.301; 95% CI, 1.368-7.964; P = .008) as independent factors for clinical failure. Among patients affected by a non-MDRO NVO, OT was not associated with an increased risk of clinical failure (aOR, 0.487; 95% CI, .133-1.782; P = .271), even after adjustment for the propensity score of receiving OT. In the subgroup of patients with staphylococcal or unknown etiology, NVO rifampin was independently associated with favorable outcome (aOR, 0.315; 95% CI, .105-.949; P = .040).

Conclusions: An entirely oral, highly bioavailable treatment, including rifampin, may be as effective as parenteral treatment in selected patients with NVOs.

Keywords: antibiotic therapy; oral therapy; outcome; vertebral osteomyelitis.