[F]FDG PET/CT Imaging Is Associated with Lower In-Hospital Mortality in Patients with Pyogenic Spondylodiscitis-A Registry-Based Analysis of 29,362 Cases.

BACKGROUND

While MRI is the primary diagnostic tool for the diagnosis of spondylodiscitis, the role of [F]-fluorodeoxyglucose ([F]FDG) PET/CT is gaining prominence. This study aimed to determine the frequency of [F]FDG PET/CT usage and its impact on the in-hospital mortality rate in patients with spondylodiscitis, particularly in the geriatric population.

METHODS

We conducted a Germany-wide cross-sectional study from 2019 to 2021 using an open-access, Germany-wide database, analyzing cases with ICD-10 codes M46.2-, M46.3-, and M46.4- ('Osteomyelitis of vertebrae', 'Infection of intervertebral disc (pyogenic)', and 'Discitis unspecified'). Diagnostic modalities were compared for their association with in-hospital mortality, with a focus on [F]FDG PET/CT.

RESULTS

In total, 29,362 hospital admissions from 2019 to 2021 were analyzed. Of these, 60.1% were male and 39.9% were female, and 71.8% of the patients were aged 65 years and above. The overall in-hospital mortality rate was 6.5% for the entire cohort and 8.2% for the geriatric subgroup ( < 0.001). Contrast-enhanced (ce) MRI (48.1%) and native CT (39.4%) of the spine were the most frequently conducted diagnostic modalities. [F]FDG PET/CT was performed in 2.7% of cases. CeCT was associated with increased in-hospital mortality (OR = 2.03, 95% CI: 1.90-2.17, < 0.001). Cases with documented [F]FDG PET/CT showed a lower frequency of in-hospital deaths (OR = 0.58, 95% CI: 0.18-0.50; = 0.002). This finding was more pronounced in patients aged 65 and above (OR = 0.42, 95% CI: 0.27-0.65, = 0.001).

CONCLUSIONS

Despite its infrequent use, [F]FDG PET/CT was associated with a lower in-hospital mortality rate in patients with spondylodiscitis, particularly in the geriatric cohort. This study is limited by only considering data on hospitalized patients and relying on the assumption of error-free coding. Further research is needed to optimize diagnostic approaches for spondylodiscitis.