Primary spondylodiscitis occurs through the hematogenous spread of a pathogen entering the body via a point of entry. The infection's origin often remains unclear. The oral cavity, depending on hygiene status offers opportunities for bacterial colonization. During dental procedures or through minor traumas microorganisms can enter the bloodstream and disseminate throughout the body. An association with cariogenic and periodontal bacteria has been established for infective endocarditis. This study investigates spondylodiscitis patients, with a focus on potential odontogenic origins.
In a cohort of 430 consecutive patients treated at our Level I Spine Center from 01/01/2018 to 12/31/2022, those with primary spondylodiscitis and available orthopantomograms (OPG) were retrospectively re-evaluated, emphasizing odontogenic focus aspects. Radiological features indicating a potential odontogenic focus included apical radiolucency, impacted teeth, residual roots, and vertical or cup-shaped bone loss. Patients with secondary spondylodiscitis from a previous operation (< 3 months) in the same segment were excluded.
80 patients, with a mean age of 66 (+/- 13) years, were included. Initial assessment documented an odontogenic focus in 20% (16/79) of patients. However, re-evaluation of OPGs based on specified criteria identified a potential odontogenic focus in 75%. Apical radiolucency was present in 59%, pathological bone loss in 48% , residual roots in 11% and retained teeth in 8%. Among these cases, an oral bacterium was identified in 16%, either in blood cultures or intervertebral disc samples. Among patients with a potential odontogenic focus 46% (27/59) had a concurrent infectious focus: 8 had joint infection, 6 had prior spinal infiltration, 4 had catheter-associated bloodstream infection, 3 had a urological focus, 3 had an ENT focus, 2 had a leg ulcer and 1 had endocarditis. In 46% no focus was initially found.
A potential odontogenic focus is more prevalent than initially presumed, particularly in patients where no focus is identified at first sight. We recommend a thorough diagnostic dental work-up as a standard procedure for patients with primary spondylodiscitis.