Differentiation of Native Vertebral Osteomyelitis: A Comprehensive Review of Imaging Techniques and Future Applications.

Native vertebral osteomyelitis, also termed spondylodiscitis, is an antibiotic-resistant disease that requires long-term treatment. Without proper treatment, NVO can lead to severe nerve damage or even death. Therefore, it is important to accurately diagnose the cause of NVO, especially in spontaneous cases. Infectious NVO is characterized by the involvement of 2 adjacent vertebrae and intervertebral discs, and common infectious agents include Staphylococcus aureus, Mycobacterium tuberculosis, Brucella abortus, and fungi. Clinical symptoms are generally nonspecific, and early diagnosis and appropriate treatment can prevent irreversible sequelae. Advances in pathologic histologic imaging have led physicians to look more forward to being able to differentiate between tuberculous and septic spinal discitis. Therefore, research in identifying and differentiating the imaging features of these 4 common NVOs is essential. Due to the diagnostic difficulties, clinical and radiologic diagnosis is the mainstay of provisional diagnosis. With the advent of the big data era and the emergence of convolutional neural network algorithms for deep learning, the application of artificial intelligence (AI) technology in orthopedic imaging diagnosis has gradually increased. AI can assist physicians in imaging review, effectively reduce the workload of physicians, and improve diagnostic accuracy. Therefore, it is necessary to present the latest clinical research on NVO and the outlook for future AI applications.

Drug eluting bioactive glass ceramics for fusion in spondylodiscitis: a pilot study.

Retrospective observational study. To determine the efficacy and safety of bioactive glass ceramics mixed with autograft in the treatment of spondylodiscitis. Thirty-four patients with spondylodiscitis underwent surgery using autologous bone graft augmented by antibiotic loaded bioactive glass ceramic granules. Twenty-five patients aging 6 to 77, completed 1-year follow-up. The lumbosacral junction was affected in 3, lumbar spine in 13, one each in the dorso-lumbar junction and sacrum, and 7 dorsal spines. The organism isolated was Mycobacterium tuberculosis in 15, Methicillin sensitive Staphylococcus aureus (MSSA) in 4, Pseudomonas aeruginosa in 4, Klebsiella pneumoniae in one, Burkholderia pseudomallei in 1, and mixed infections in 2. All patients had appropriate antibiotic therapy based on culture and sensitivity. Clinical and radiological evaluation of all the patients was done at 6 weeks, 3 months, 6 months, and 12 months after the surgery. Twenty-three patients improved clinically and showed radiographic fusion between 6 and 9 months. The patient with Burkholderia infection died due to fulminant septicemia with multi organ failure while another patient died at 9 months due to an unrelated cardiac event. The mean Visual Analogue Score (VAS) at the end of 1-year was 2 with radiological evidence of fusion in all patients. There were no re-infections or discharging wounds, and the 30-day re-admission rate was 0. Bioactive glass ceramics is a safe and effective graft expander in cases of spondylodiscitis. The absorption of antibiotics into the ceramic appears to help the elimination of infection.

Pyogenic spondylodiscitis in HIV-positive patients under antiretroviral therapy: A case series.

Background: The incidence of pyogenic spondylodiscitis has been increasing in countries of Europe and North America, probably due to an increasing number of persons with risk factors for this infection. It is unclear whether HIV infection in the era of antiretroviral therapy (ART) increases the risk for spondylodiscitis. Method: We present 7 cases of pyogenic spondylodiscitis of the cervical, thoracic, and lumbar spine in six individuals living with HIV under ART with suppressed viral load. Results: All patients presented with severe non-radicular pain and elevated inflammatory markers. Diagnosis was confirmed by magnetic resonance imaging (MRI) scan and isolation of the pathogen. Staphylococcus aureus was the causative pathogen in five patients. One patient suffered from an infection with Klebsiella pneumoniae followed by a mixed infection with Cutibacterium acnes and Bacillus circulans 18 months later. All patients needed surgical intervention, and the mean duration of antibiotic treatment was 17 weeks (range 12-26). Five patients recovered fully, including two persons who also suffered from endocarditis. One patient died from multi-organ failure. Conclusion: Spondylodiscitis may be seen more frequently in persons living with HIV as they grow older and suffer from comorbidities which put them at risk for this infection. HIV physicians should be aware of the infection and its risk factors.

Metagenomic next-generation sequencing identifying a rare case of Mycobacterium xenopi discitis.

Mycobacterium xenopi is a non-tuberculous mycobacterium (NTM) that sporadically causes infections in humans and can cause rare bone and joint infections in immunocompromised hosts with history of spinal surgery. This slow-growing mycobacterium takes 8-12 weeks to grow on culture. Metagenomic next-generation sequencing (MNGS) is a highly sensitive and specific plasma-based microbial cell-free DNA test that can detect M. xenopi weeks prior to culture growth. We present a case of M. xenopi lumbosacral discitis with presacral abscess in an immunocompromised woman without history of spinal surgery which was detected by MNGS 8 weeks prior to culture growth. The patient's discitis resolved with an M. xenopi-directed regimen of ethambutol, rifampin and azithromycin. This case illustrates the utility of next-generation sequencing tests in rapid diagnosis of rare and opportunistic infections, as compared with traditional diagnostic tests, with supporting contextual clinical and diagnostic findings.

Determining the prevalence and risk factors for positive bacterial culture in canine discospondylitis: 120 cases.

BACKGROUND: Identification of the aetiologic agent in canine discospondylitis is infrequent; and risk factors for a positive bacterial culture have not previously been reported. METHODS: Medical records at three institutions were searched to identify clinical features of dogs with discospondylitis diagnosed via radiography or cross-sectional imaging. Inclusion in this retrospective case-control study required culture of one or more samples. Multivariable binary logistic regression identified features associated with a positive culture. RESULTS: Fifty (42%) of 120 dogs had one or more positive culture results obtained from either urine (28/115), blood (25/78), intervertebral disc aspiration (10/34) or cerebrospinal fluid (1/18). A positive culture was associated with higher bodyweight (p = 0.002, odds ratio [OR] = 1.054, 95% confidence interval [CI]: 1.019-1.089), more sample types cultured (p = 0.037, OR = 1.806, 95% CI: 1.037-3.147) and institution (p = 0.021). The presence of possibly associated preceding events (e.g., surgery), pyrexia, number of disc sites affected and serum C-reactive protein result, among other features, were not statistically significant. LIMITATIONS: All isolates cultured were included since differentiation of true aetiologic agents from contaminants was not possible without histological confirmation and culture from surgical or postmortem biopsies. CONCLUSIONS: Clinical features typically associated with infection were not identified as risk factors for positive culture in canine discospondylitis. The statistical significance of the institution suggests that standardisation of sampling protocols is necessary.

Post-COVID-19 Spondylodiscitis: A Case Study and Review of the Literature.

COVID-19 is currently a major health problem, leading to respiratory, cardiovascular and neurological complications, with additional morbidity and mortality. Spinal infections are rare, representing around 1% of all bone infections and comprising less than 2 per 10,000 of all hospitalizations in tertiary care centers. Spondylodiscitis is a complex disease, with challenging diagnosis and management. We report the case of a 45-year-old man, non-smoker hospitalized for severe COVID-19 disease with respiratory failure. Post-COVID-19, in the 8th week after discharge, he was diagnosed by magnetic resonance imaging with spondylodiscitis, but etiology was not confirmed by microbiological investigations. Antibiotics were used, considering the identification of MRSA from cultures of pleural fluid and nasal swab, but surgical intervention was not provided. Clinic, biologic and imagistic were improved, but rehabilitation and long term follow up are necessary. We concluded that spondylodiscitis with spinal abscess is a rare but severe complication post-COVID-19 disease, due to dysbalanced immune response related to the respiratory viral infection, endothelial lesions, hypercoagulation and bacterial superinfection.

Discitis-osteomyelitis: optimizing results of percutaneous sampling.

Vertebral discitis-osteomyelitis is an infection of the spine that involves the intervertebral disc and the adjacent vertebral body but may also extend into the paraspinal and epidural soft tissues. If blood cultures and other culture data fail to identify a causative microorganism, percutaneous sampling is indicated to help guide targeted antimicrobial therapy. Despite limited supporting evidence, withholding antimicrobial therapy for up to 2 weeks is recommended to maximize microbiological yield, although literature supporting this recommendation is limited. During the procedure, technical factors that may improve yield include targeting of paraspinal fluid collections or soft tissue abnormalities for sampling, acquiring multiple core samples if possible, and use of larger gauge needles when available. Repeat sampling may be indicated if initial percutaneous biopsy is negative but should be performed no sooner than 72 h after the initial percutaneous biopsy to ensure adequate time for culture results to return.

Aspergillus terreus spondylodiscitis following acupuncture and acupotomy in an immunocompetent host: case report and literature review.

Aspergillus terreus is a fungus responsible for various infections in human beings; however, spine involvement is uncommon. Herein, we report a case of A. terreus spondylodiscitis following acupuncture and acupotomy in an immunocompetent Chinese patient. Admission lumbar magnetic resonance imaging (MRI) revealed infection at the L4/5 level without significant vertebral destruction. After unsuccessful symptomatic and anti-tuberculosis treatments, A. terreus was identified through culture, microscopy of isolate, histological examination and VITEK system. Intravenous voriconazole was then given; however, the patient's spinal condition deteriorated rapidly, resulting in evident destruction of the L4/5 vertebral bodies. Surgeries including L4/5 intervertebral disc debridement, spinal canal decompression, posterior lumbar interbody fusion (PLIF) with allogeneic fibula ring fusion cages, and posterior pedicle screw fixation were then performed. Imaging findings at one-month and six-month follow-up suggested that the patient was successfully treated. This case highlighted two important points: firstly, although acupuncture and acupotomy are generally regarded as safe conservative treatments for pain management, they can still lead to complications such as fungal spinal infection. Therefore, vigilance is necessary when considering these treatments; secondly, PLIF with allogeneic fibula ring fusion cages may be beneficial for A. terreus spondylodiscitis patients with spinal instability.

Bacteroides fragilis Bacteremia Complicated by Spondylodiscitis, Spinal Epidural Abscess, and Sepsis: A Case Report.

BACKGROUND Pyogenic spondylitis comprises several clinical entities, including native vertebral osteomyelitis, septic discitis, pyogenic spondylodiscitis, and epidural abscess. The lumbar spine is most often infected, followed by the thoracic and cervical areas. It mainly develops (i) after spine surgery; (ii) from history of blunt trauma to the spinal column; (iii) from infections in adjacent structures (such as soft tissues); (iv) from iatrogenic inoculation after invasive procedures (such as lumbar puncture); and (v) from hematogenous bacterial spread to the vertebra (mainly through the venous route). Any delay in diagnosis and treatment can lead to significant spinal cord injury, permanent neurological damage, septicemia, and death. CASE REPORT We describe a 63-year-old man with no significant past medical history who presented with fever and an altered level of consciousness. Significant thoracic spine pain was also reported during the last 3 months. The final diagnosis was vertebral spondylodiscitis, contiguous spinal epidural abscess, and sepsis due to Bacteroides fragilis bacteremia. Clinical recovery was achieved after surgical decompressive therapy with abscess drainage combined with appropriate antibiotic therapy for 12 weeks. The primary focus of the infection was not clarified, despite all the investigations that were performed. CONCLUSIONS Spondylodiscitis, spinal epidural abscess, and sepsis as complications of Bacteroides fragilis bacteremia are rare in a patient without any previously known predisposing conditions and without an obvious primary focus. Early diagnosis and proper treatment of anaerobic spondylodiscitis, especially if epidural abscess and sepsis are present, are of great importance to reduce mortality and avoid long-term complications.

A Comparison of CT-Guided Bone Biopsy and Fluoroscopic-Guided Disc Aspiration as Diagnostic Methods in the Management of Spondylodiscitis.

BACKGROUND AND PURPOSE: Percutaneous tissue biopsy is a key step in the diagnosis and management of spondylodiscitis, often utilizing CT-guided bone biopsy or fluoroscopic-guided disc aspirations. Our objective was to compare radiation exposure, procedure time, sedation requirement & yield between the two modalities. MATERIALS AND METHODS: 103 patients in 2 cohorts underwent fluoroscopic-guided disc aspirations (n = 47) or CTguided bone biopsy (n = 46) for diagnosis of spondylodiscitis. Patient and imaging data were gathered to ensure matched cohorts. Interventional and post-procedural data included radiation exposure, procedure time, complications, and microbiological details. Yield was calculated using MRI findings as the gold standard for infection. RESULTS: There were no significant differences between cohorts in demographics, symptom duration, or pre-procedure antibiotics use. CT-guided bone biopsy required more general anesthesia (26% vs 0%, P < 0.001), had longer radiation exposure time (60 ± 24s vs 2 ± 3s, P < 0.001), radiation dose (114.4 ± 71.6 mGy vs 70.4 ± 147.2 mGy), and procedure time (62 ± 14m vs 31 ± 23m, P < 0.001) than fluoroscopic-guided disc aspirations. There was no significant difference in yield (34% vs 32%, P = 0.661), and it was not affected by antibiotic use. CONCLUSIONS: Both modalities have similar utility in isolating causative organisms in suspected cases of spondylodiscitis. Our results suggest that increased radiation exposure, longer procedure time, and increased anesthesia use are relative disadvantages of CT-guided biopsy without an increase in yield. Controlled trials may be beneficial in determining the optimal choice in different scenarios.

Clinical profile, diagnosis, treatment, and outcome of patients with tubercular versus nontubercular causes of spine involvement: A retrospective cohort study from India.

Background: In tuberculosis (TB) endemic areas, other pyogenic causes of spine involvement may be missed. The study aimed to describe TB and non-TB causes of spine involvement and identify features that can help in differentiating them. Methods: A retrospective cohort study was conducted to screen the clinical records of all admitted patients (Kasturba Hospital, Manipal) in 2018-20 for a diagnosis of spondylitis and/or sacroiliitis. The clinical features, radiological findings, laboratory parameters, treatment details, and outcomes were compared among those diagnosed with confirmed TB, confirmed brucellosis, or confirmed pyogenic infection. A scoring system was also developed to differentiate spondylodiscitis due to tuberculous and pyogenic causes. The qualitative variables were compared using the Chi-square test, while quantitative variables were compared using the one-way analysis of variance test. Results: Of 120 patients with spine infections, a total of 85 patients were confirmed with the microbiological diagnosis of interest. Involvement of the thoracic spine, longer duration of illness, and caseous granulomatous reaction on histopathology was more common in TB patients. Male gender, involvement of lumbar vertebra, and neutrophilic infiltrate on histopathology were more common in brucellosis patients. Male gender, diabetes mellitus, involvement of lumbar vertebra, neutrophilic infiltrate on histopathology, leukocytosis, and increased C-reactive protein were more commonly seen in patients with pyogenic infection. The scoring system had a sensitivity and specificity of 75% and 91%, respectively, when used to differentiate TB from pyogenic infection. Conclusions: In resource-limited settings, suggestive findings can be used to decide empiric therapy.

Spine Infections: The Role of Fluorodeoxyglucose Positron Emission Tomography (FDG PET) in the Context of the Actual Diagnosis Guideline.

Spondylodiscitis is an infectious process that requires numerous health care professionals to be clearly diagnosed and eventually successfully treated. It implies a variety of microbiological agents and conditions; during the diagnostic workup, it is difficult to correctly identify them, and the clinician has to rapidly choose the correct treatment to avoid permanent injuries to the patient. In this context, we conducted a review to better understand the most suitable use of Positron Emission Tomography with 18-Fluoro-deossi-glucose (FDG PET) in a patient suspected of spondylodiscitis, based on current guidelines and literature.. We wanted to review the role of FDG PET in the spondylodiscitis diagnosis and follow up in the context of the current guidelines.

Kingella kingae Spondylodiscitis: Treatment Failure With Flucloxacillin.

Kingella kingae infections generally respond well to most beta-lactam antibiotics. We investigated an antibiotic treatment failure in a 3-year-old with K. kingae L3-4 spondylodiscitis. Her disease progressed even after 19 days of high-dose intravenous flucloxacillin. The clinical isolate did not produce a beta-lactamase and despite phenotypic testing and whole-genome sequencing, the mechanism of flucloxacillin resistance remains unknown.

Diagnostic yield of image-guided biopsy in patients with suspected infectious spondylodiscitis : a prospective study from a tuberculosis-endemic country.

AIMS: The aims of this study were to determine the diagnostic yield of image-guided biopsy in providing a final diagnosis in patients with suspected infectious spondylodiscitis, to report the diagnostic accuracy of various microbiological tests and histological examinations in these patients, and to report the epidemiology of infectious spondylodiscitis from a country where tuberculosis (TB) is endemic, including the incidence of drug-resistant TB. METHODS: A total of 284 patients with clinically and radiologically suspected infectious spondylodiscitis were prospectively recruited into the study. Image-guided biopsy of the vertebral lesion was performed and specimens were sent for various microbiological tests and histological examinations. The final diagnosis was determined using a composite reference standard based on clinical, radiological, serological, microbiological, and histological findings. The overall diagnostic yield of the biopsy, and that for each test, was calculated in light of the final diagnosis. RESULTS: The final diagnosis was tuberculous spondylodiscitis in 250 patients (88%) and pyogenic spondylodiscitis in 22 (7.8%). Six (2.1%) had a noninfectious condition-mimicking infectious spondylodiscitis, and six (2.1%) had no definite diagnosis and improved without specific treatment. The diagnosis was made by image-guided biopsy in 152 patients (56%) with infectious spondylodiscitis. Biopsy was contributory in identifying 132/250 patients (53%) with tuberculous spondylodiscitis, and 20/22 patients (91%) with pyogenic spondylodiscitis. Histological examination was the most sensitive diagnostic modality, followed by Xpert MTB/RIF assay. CONCLUSION: Image-guided biopsy has a reasonably high diagnostic yield in patients with suspected infectious spondylodiscitis. A combination of histological examination, Xpert MTB/RIF assay, bacterial culture, and sensitivity provides high diagnostic accuracy in a country in which TB is endemic. Cite this article: Bone Joint J 2022;104-B(1):120-126.

Influence of microbiological diagnosis on the clinical course of spondylodiscitis.

PURPOSE: This study sought to recognize differences in clinical disease manifestations of spondylodiscitis depending on the causative bacterial species. METHODS: We performed an evaluation of all spondylodiscitis cases in our clinic from 2013-2018. 211 patients were included, in whom a causative bacterial pathogen was identified in 80.6% (170/211). We collected the following data; disease complications, comorbidities, laboratory parameters, abscess occurrence, localization of the infection (cervical, thoracic, lumbar, disseminated), length of hospital stay and 30-day mortality rates depending on the causative bacterial species. Differences between bacterial detection in blood culture and intraoperative samples were also recorded. RESULTS: The detection rate of bacterial pathogens through intraoperative sampling was 66.3% and could be increased by the results of the blood cultures to a total of 80.6% (n = 170/211). S. aureus was the most frequently detected pathogen in blood culture and intraoperative specimens and and was isolated in a higher percentage cervically than in other locations of the spine. Bacteremic S. aureus infections were associated with an increased mortality (31.4% vs. overall mortality of 13.7%, p = 0.001), more frequently developing complications, such as shock, pneumonia, and myocardial infarction. Comorbidities, abscesses, length of stay, sex, and laboratory parameters all showed no differences depending on the bacterial species. CONCLUSION: Blood culture significantly improved the diagnostic yield, thus underscoring the need for a structured diagnostic approach. MSSA spondylodiscitis was associated with increased mortality and a higher incidence of complications.

Infectious spondylodiscitis and kyphosis correction in an infant: a case report.

BACKGROUND: Neonatal infectious spondylodiscitis is a rare bony infection with atypical clinical presentation and non-specific systemic symptoms. Diagnosis and treatment are often delayed resulting in vertebral destruction and severe complications. We retrospectively reviewed the case of an infant with infectious spondylodiscitis resulting in T12 body destruction and marked angular kyphosis. CASE-REPORT: A 4-week-old infant developed an infectious spondylodiscitis resulting in destruction of the T12 vertebral body and involvement of disc between T12 and L1. At 6 months of age, X-ray showed a marked thoracolumbar angular kyphosis above 50 Cobb degrees. Therefore, the patient underwent single time surgery with double anterior and posterior approach. At 9 years follow up, clinical and radiological findings show a stable correction with good aesthetic appearance. CONCLUSION: Neonatal spondylodiscitis could lead to marked kyphosis similar to the congenital one. Since treatment with casts and tutors is often inefficacious, prompt surgery should be considered. The double anterior and posterior approach is the best option in this condition.

Implementation of a multidisciplinary infections conference improves the treatment of spondylodiscitis.

Establishing a multidisciplinary approach regarding the treatment of spondylodiscitis and analyzing its effect compared to a single discipline approach. 361 patients diagnosed with spondylodiscitis were included in this retrospective pre-post intervention study. The treatment strategy was either established by a single discipline approach (n = 149, year 2003-2011) or by a weekly multidisciplinary infections conference (n = 212, year 2013-2018) consisting of at least an orthopedic surgeon, medical microbiologist, infectious disease specialist and pathologist. Recorded data included the surgical and antibiotic strategy, complications leading to operative revision, recovered microorganisms, as well as the total length of hospital and intensive care unit stay. Compared to a single discipline approach, performing the multidisciplinary infections conference led to significant changes in anti-infective and surgical treatment strategies. Patients discussed in the conference showed significantly reduced days of total antibiotic treatment (66 ± 31 vs 104 ± 31, p < 0.001). Moreover, one stage procedures and open transpedicular screw placement were more frequently performed following multidisciplinary discussions, while there were less involved spinal segments in terms of internal fixation as well as an increased use of intervertebral cages instead of autologous bone graft (p < 0.001). Staphylococcus aureus and Staphylococcus epidermidis were the most frequently recovered organisms in both patient groups. No significant difference was found comparing inpatient complications between the two groups or the total in-hospital stay. Implementation of a weekly infections conference is an effective approach to introduce multidisciplinarity into spondylodiscitis management. These conferences significantly altered the treatment plan compared to a single discipline approach. Therefore, we highly recommend the implementation to optimize treatment modalities for patients.