Modified percutaneous vertebral body-intervertebral disc biopsy combined with genetic testing for the diagnosis of early-stage pyogenic spondylodiscitis: a retrospective cohort study

OBJECTIVE: This study aims to assess the diagnostic efficacy of a novel integrated approach that combines a modified percutaneous disc biopsy technique with 16 S rRNA gene sequencing to enhance pathogen identification in patients with early suspected pyogenic spondylodiscitis (PS). METHODS: A retrospective cohort study was conducted, enrolling 66 patients who underwent percutaneous biopsy based on clinical and MRI findings indicative of early PS between January 2021 and January 2024. Patients were categorized into two groups: Group A (n = 31), which received traditional transpedicular biopsy coupled with 16 S rRNA gene sequencing, and Group B (n = 35), which received the modified transpedicular-vertebral-discal biopsy combined with genetic testing. A composite follow-up, including clinical symptoms, imaging, and laboratory findings at ≥ 6 months, served as the gold standard. Pathogen detection rates, complication rates, and pathogen profiles were compared between the groups. RESULTS: Baseline characteristics were comparable between the groups. The pathogen detection rate in Group B (85.7%, 30/35) was significantly higher than that in Group A (51.6%, 16/31), with a statistically significant difference (P < 0.01). No serious procedure-related complications were observed in either group. The predominant infection in both groups was monomicrobial bacterial infection, with Staphylococcus aureus identified as the most common pathogen. CONCLUSION: The modified percutaneous biopsy technique combined with 16 S rRNA gene sequencing significantly improves pathogen detection in early pyogenic spondylodiscitis without increasing the risk of complications. This integrated approach demonstrates substantial diagnostic value and shows promise as a first-line minimally invasive diagnostic method.