Impact of MRI, CT, and Clinical Characteristics on Microbial Pathogen Detection Using CT-Guided Biopsy for Suspected Spondylodiscitis

Abstract

Spondylodiscitis accounts for 2–7% of osteomyelitis cases and is characterized by pain, systemic inflammation, and permanent neurological deficits. We aimed to identify imaging characteristics and clinical parameters to successfully predict microbiological pathogens by computed tomography (CT)-guided biopsy in suspected spondylodiscitis cases. Forty consecutive patients (mean age 65.1 years) with suspected spondylodiscitis underwent CT-guided biopsy. CT features (non-sclerotic endplate erosions (NSEs)), magnetic resonance criteria (paravertebral/epidural abscess (PA/EA) formation), and clinical data (C-reactive protein (CRP) > 50 mg/L) were assessed for their predictive potential. NSEs were detected in 6/11 (54.5%) and 1/29(3.4%) patients with positive and negative microbiology, respectively. PA and EA, respectively, were present in 7/11(63.6%) and 3/11 patients with positive microbiology and 7/29 (24.1%) and 2/29 patients with negative microbiology. CRP > 50 was observed in 7/11 (63.6%) and in 7/29 (24.1%) patients with positive and negative microbiology, respectively. Three double combinations possessed near-perfect specificity (PA + NSE, 100%; PA + CRP > 50, 96.6%; NSE + CRP > 50, 96.6%). The top three Youden indices included combinations with NSE. Since CT/magnetic resonance (MR) imaging and CRP are routinely used to evaluate spondylodiscitis, the presented diagnostic criteria and combinations can aid decision-making for biopsy.

Vertebral Bone Marrow and Endplate Assessment on MR Imaging for the Differentiation of Modic Type 1 Endplate Changes and Infectious Spondylodiscitis

“…As a result of it being largely available and a rapid alternative when MR imaging is unavailable or contraindicated, multidetector CT has been recently investigated for the assessment of suspected spondylodiscitis [47,48]. CT was accurate in demonstrating endplate and cortical destruction, with a sensitivity of 79% and a specificity of 100% in detecting acute spondylodiscitis [47].…”

“…Moreover, MR imaging may identify the very early stages of spondylodiscitis, with edema but without obvious bone destruction versus active degeneration [28,29,36]. On CT-guided biopsy, a high probability of positive pathogen detection was found in non-sclerotic endplate erosions [48]. These erosions may correspond to MR endplate blurring or subsequent destruction.…”

Early Imaging and Course-of-Disease Control Markers of Pyogenic Vertebral Osteomyelitis

“…За клінічним перебігом виокремлюють гострі, підгострі і хронічні спондилодисцити. Традиційно при тривалості захворювання менше двох місяців гнійний остеомієліт хребта розглядають як гострий, від двох до шести місяців -як підгострий, хронічний перебіг для неспецифічного ураження встановлюють при тривалості процесу більше шести місяців, специфічного -більше дванадцяти місяців [5].…”

“…According to the clinical course, spondylodiscitis can be acute, subacute and chronic. Traditionally, when the disease lasts less than two months, pyogenic vertebral osteomyelitis is considered to be acute, from 2 to 6 months -subacute, and the chronic course for nonspecifi c involvement is established when the process lasts more than 6 months, while specifi c involvement -when it lasts more than 1 year [5].…”

Spinal disorders mimicking infection

“…Spondylodiscitis represents 2–7% of all osteomyelitis cases, with an annual incidence of 1/100,000 to 1/250,000 [ 1 – 3 ]. Disco-vertebral biopsy is usually not mandatory if a pathogenic agent is detected by blood culture, yet the detection rate is low (24%) [ 4 ].…”