This study aims to evaluate in patients hospitalized for vertebral osteomyelitis (VO) the effectiveness of bacteriological diagnosis and the yield of percutaneous needle biopsy (PNB) and to identify factors associated with the result of PNB. This retrospective, two-centre study was conducted between 2000 and 2009. Data on patients with VO were retrieved from the diagnosis database and confirmed by checking medical records. A total of 300 patients with VO were identified; 31 received antibiotics without bacteriological diagnosis, and 269 patients with spondylodiscitis imaging were included. Eighty-three (30.9%) and 18 (6.7%) infections were documented by blood cultures and by bacteriological samples other than PNB, respectively; 168 patients with no bacteriological diagnosis had PNB. Of these, 92 (54.8%) were positive and identified the pathogen and 76 (45.2%) were negative. The most common bacteria were Staphylococcus aureus (34.3%), Streptococcus spp. (20.6%) and coagulase-negative staphylococcus (14.8%). After multivariate analysis, the only factor associated with negative PNB was previous antibiotic intake (OR: 2.31 [1.07–5.00]). When VO was suspected on imaging, bacteriological investigation identified the microorganism in 209/300 (70%) of the cases. The yield of PNB was 54.8%. The only predictor of PNB negativity was previous antibiotic intake. Therefore, we believe that a second PNB should be done after a sufficient delay withdrawal of antibiotics if the first sample was negative. The study was retrospectively registered by the local ethics committee (N°E2019-61).

这项研究旨在评估住院椎骨骨髓炎（VO）的患者细菌学诊断的有效性和经皮穿刺活检（PNB）的产率，并确定与PNB结果相关的因素。这项回顾性，两中心研究于2000年至2009年进行。从诊断数据库中检索出VO患者的数据，并通过检查医疗记录进行确认。总共确定了300例VO患者。31例接受了无细菌学诊断的抗生素，包括269例脊椎盘炎成像患者。血液培养和PNB以外的细菌学样本分别记录了八十三（30.9％）和18（6.7％）感染；168名无细菌学诊断的患者有PNB。其中92（54。8％）为阳性，并鉴定出病原体； 76（45.2％）为阴性。最常见的细菌是金黄色葡萄球菌（34.3％），链球菌属。（20.6％）和凝固酶阴性葡萄球菌（14.8％）。经过多变量分析后，与PNB阴性相关的唯一因素是以前的抗生素摄入量（OR：2.31 [1.07–5.00]）。当在影像学上怀疑有VO时，细菌学调查在209/300（70％）的病例中鉴定出了微生物。PNB的产率为54.8％。PNB阴性的唯一预测因素是以前的抗生素摄入量。因此，我们认为如果第一个样品为阴性，则应在充分延迟撤回抗生素后再进行第二次PNB。该研究已由当地伦理委员会（N°E2019-61）进行了回顾性注册。