Management of Pyogenic Spinal Infection, review of literature

Risk Factors Associated with Pyogenic Spinal Infections among Intravenous Drug Users and Nonusers

Purpose

To identify the differences in patient factors, presentation, treatment course, and outcomes of intravenous drug users (IVDA) vs. nonusers (non-IVDA) presenting with pyogenic spinal infections. Study Design/Setting. Retrospective case series.

Methods

We identified all cases involving spinal infections at our institution between May 2017 and January 2023. Postsurgical infections were excluded, and patients were separated into IVDA and non-IVDA groups. The patient charts were reviewed and analyzed for statistical or clinically significant differences using RStudio (2019 version 3.6.2). Our institutional review board approved this study, IRB# 2020-277, iRISID-2023-1384.

Results

Fifty patients (29 males and 21 females) with primary pyogenic spinal infections were included in our study. There were fourteen patients (28.0%) in the IVDA group. The mean age in the IVDA group was 50.6 vs. 61.9 years (p < 0.05) in the non-IVDA group. The average length of stay (LOS) in the IVDA group was 15.8 vs. 14.0 days (p = 0.54) in the non-IVDA group, with no significant difference in readmissions or disposition. Twenty-three non-IVDA patients were diagnosed with diabetes, while eight IVDA patients had a psychiatric diagnosis (other than substance abuse). There were no significant differences in microbial isolate or the duration of antibiotics.

Conclusion

In our study population, there is a high incidence of intravenous drug abuse (IVDA), psychiatric disease, diabetes, and chronic kidney disease. Analysis shows a trend of two distinct patient populations. Patients without a history of IVDA were significantly older than those with IVDA and significantly more likely to have medical comorbidities including hyperlipidemia, diabetes, chronic kidney disease, and malignancy than those with IVDA history. Patients with IVDA were younger with significantly higher rates of smoking and psychiatric disorders. IVDA patients struggled to receive continued psychiatric/addiction treatment after discharge, an area for significant improvement. Due to a small sample size and single urban institution setting, this study may be underpowered to demonstrate differences in healthcare resource consumption.

The Need for Comprehensive Medical Management in Pyogenic Spondylodiscitis: A Review Article

The incidence of spontaneous or primary spondylodiscitis has been increasing over the years, affecting the aging population with multiple comorbidities. Several conditions influencing treatment outcomes stand out, such as diabetes mellitus, renal insufficiency, cardiovascular and respiratory dysfunction, and malnutrition. Due to these, the question arises regarding properly managing their current conditions and pre-existing disease states. Treatment plans must consider all concomitant comorbidities rather than just the infectious process. This can be done with the help of multidisciplinary teams to provide comprehensive care for patients with pyogenic spondylodiscitis. To date, there is no article regarding comprehensive medicine for spontaneous pyogenic spondylodiscitis; hence, this paper reviews the evidence available in current literature, recognizes knowledge gaps, and suggests comprehensive care for treating patients with spinal infections. Pre-requisites for implementing multidisciplinary teams include leadership, administrative support, and team dynamics. This group comprises an appointed leader, coordinator, and different subspecialists, such as orthopedic surgeons, infectious disease specialists, internists, rehabilitation doctors, psychiatrists, microbiologists, radiologists, nutritionists, pharmacologists, nurses, and orthotists working together with mutual trust and respect. Employing collaborative teams allows faster time for diagnosis and improves clinical outcomes, better quality of life, and patient satisfaction. Forefront communication is clear and open between all team members to provide holistic patient care. With these in mind, the need for employing multidisciplinary teams and the feasibility of its implementation emerges, showing a promising and logical path toward providing comprehensive care in managing multimorbid patients with pyogenic spondylodiscitis.

Thoracic spine infection caused by Pseudomonas fluorescens: A case report and review of literature

BACKGROUND

The clinical incidence of spinal infection is gradually increasing, and its onset is insidious, easily leading to missed diagnosis and misdiagnosis, which may lead to serious complications such as nervous system dysfunction, spinal instability and/or deformity, and cause a huge burden on society and families. Early identification of the causative agent and precision medicine will greatly reduce the suffering of patients. At present, the main pathogenic bacteria that cause spinal infection are Staphylococcus aureus, Streptococcus, Pneumococcus, Escherichia coli, and Klebsiella. There are no reports of spinal infection caused by Pseudomonas fluorescens.

CASE SUMMARY

We report a 32-year-old female patient with spinal infection. She presented with flank pain, initially thought to be bone metastases or bone tuberculosis, and had a family background of tumors. Her clinical features and changes in imaging and laboratory tests led to the suspicion of thoracic spine infection. Histopathology of the lesion showed inflammation, tissue culture of the lesion was negative several times, and the possible pathogen - Pseudomonas fluorescens was found after gene sequencing of the lesion. The patient recovered completely after a full course of antibiotic treatment.

CONCLUSION

This report increases the range of pathogens involved in spinal infections, highlights the unique advantages of gene sequencing technology in difficult-to-diagnose diseases, and validates conservative treatment with a full course of antibiotics for spinal infections without complications.

Isolated Fusobacterium nucleatum Growth in the Blood Culture of a Middle-Aged Man With Lumbar Discitis, Surrounding Psoas Abscesses, and an Inferior Vena Cava Thrombus

Pyogenic spinal infections (PSI) have an incidence of 0.5-2.2 cases per 100,000 population, though diagnosis can be delayed by up to three months. The incidence of Fusobacterium nucleatum bacteremia is rare, occurring in 0.22-0.34 cases per 100,000 population, whilst its implication in spinal infections is rarer still. A man in his 60s with a background of chronic lower back pain presented to the emergency department with a two-week history of worsening back pain associated with fever and difficulty voiding. He was initially managed as pyelonephritis due to the recent history of urinary tract infection (UTI) with fever and flank pain. However, there were radiculopathy and bilateral pain on hip flexion with reduced power on the right side. The light-touch sensation was reduced over the right hallux and distal L4 dermatome. These neurological deficits associated with deranged infective markers made a diagnosis of discitis plausible. Discitis and native vertebral osteomyelitis (NVO) should be suspected in patients reporting a fever and back pain of recent onset or increasing in severity. Once discitis was confirmed, the patient was subsequently tested for tuberculosis (TB) using a T-SPOT, human immunodeficiency virus (HIV), hepatitis B virus, and hepatitis C virus, with no positive findings, but in the days following, blood cultures yielded F. nucleatum. Guided by knowing the natural reservoirs in the body, establishing the source of F. nucleatum could be achieved through head and neck imaging and investigating the gastrointestinal tract for malignant or inflammatory processes.

Vacuum assisted closure and local drug delivery systems in spinal infections: A review of current evidence

Background

Spinal infections are still showing increased incidence throughout the years as our surgical capabilities increase, coupled with an overall aging population with greater number of chronic comorbidities. The management of spinal infection is of utmost importance, due to high rates of morbidity and mortality, on top of the general difficulty in eradicating spinal infection due to the ease of hematogenous spread in the spine. We aim to summarize the utility of vacuum-assisted closure (VAC) and local drug delivery systems (LDDS) in the management of spinal infections.

Methods

A narrative review was conducted. All studies that were related to the use of VAC and LDDS in Spinal Infections were included in the study.

Results

A total of 62 studies were included in this review. We discussed the utility of VAC as a tool for the management of wounds requiring secondary closure, as well as how it is increasingly being used after primary closure as prophylaxis for surgical site infections in high-risk wounds of patients undergoing spinal surgery. The role of LDDS in spinal infections was also discussed, with preliminary studies showing good outcomes when patients were treated with various novel LDDS.

Conclusions

We have summarized and given our recommendations for the use of VAC and LDDS for spinal infections. A treatment algorithm has also been established, to act as a guide for spine surgeons to follow when tackling various spinal infections in day-to-day clinical practice.

The Potential of a CT-Based Machine Learning Radiomics Analysis to Differentiate Brucella and Pyogenic Spondylitis

Background

Pyogenic spondylitis (PS) and Brucella spondylitis (BS) are common spinal infections with similar manifestations, making their differentiation challenging. This study aimed to explore the potential of CT-based radiomics features combined with machine learning algorithms to differentiate PS from BS.

Methods

This retrospective study involved the collection of clinical and radiological information from 138 patients diagnosed with either PS or BS in our hospital between January 2017 and December 2022, based on histopathology examination and/or germ isolations. The region of interest (ROI) was defined by two radiologists using a 3D Slicer open-source platform, utilizing blind analysis of sagittal CT images against histopathological examination results. PyRadiomics, a Python package, was utilized to extract ROI features. Several methods were performed to reduce the dimensionality of the extracted features. Machine learning algorithms were trained and evaluated using techniques like the area under the receiver operating characteristic curve (AUC; confusion matrix-related metrics, calibration plot, and decision curve analysis to assess their ability to differentiate PS from BS. Additionally, permutation feature importance (PFI; local interpretable model-agnostic explanations (LIME; and Shapley additive explanation (SHAP) techniques were utilized to gain insights into the interpretabilities of the models that are otherwise considered opaque black-boxes.

Results

A total of 15 radiomics features were screened during the analysis. The AUC value and Brier score of best the model were 0.88 and 0.13, respectively. The calibration plot and decision curve analysis displayed higher clinical efficiency in the differential diagnosis. According to the interpretation results, the most impactful features on the model output were wavelet LHL small dependence low gray-level emphasis (GLDN).

Conclusion

The CT-based radiomics models that we developed have proven to be useful in reliably differentiating between PS and BS at an early stage and can provide a reliable explanation for the classification results.

Pyogenic spondylitis caused by Escherichia coli: A case report and literature review

BACKGROUND

Pyogenic spondylitis is often manifested as atypical low back pain and fever, which makes it easy to be confused with other diseases. Here we report a case of pyogenic spondylitis and describe the diagnosis and treatment based on the related literature.

CASE SUMMARY

The reported case suffered from pyogenic spondylitis caused by Escherichia coli and complicated with bacteremia and psoas abscess. Acute pyelonephritis was initially diagnosed due to atypical symptoms. Symptoms were improved from antibiotic treatment while developing progressive lower limb dysfunction. One month post the admission, the patient underwent anterior lumbar debridement + autogenous iliac bone graft fusion + posterior percutaneous screw-rod internal fixation, and received 6 wk of antibiotic treatment after the operation. Reexamination 4 mo post the operation showed that the patient had no evident pain in the waist, and walked well with no evident dysfunction of lower limbs.

CONCLUSION

Here we describe the application value of several imaging examinations, such as X-ray, computed tomography and magnetic resonance imaging, and certain tests like erythrocyte sedimentation rate and C-reactive protein in the clinical treatment of pyogenic spondylitis. This disease requires early diagnosis and treatment. Sensitive antibiotics should be used in early stages and surgical intervention should be taken if necessary, which may help for a speedy recovery and prevent the occurrence of severe complications.

A Comparison of Negative Pressure and Conventional Therapy in Spine Infections: A Single-Center Retrospective Study

Purpose: To investigate the effectiveness and safety of negative-pressure wound therapy (NPWT) in treating primary spinal infections. Methods: Patients who underwent surgical treatment for primary spinal infection between January 2018 and June 2021 were retrospectively evaluated. They were divided into two groups based on the type of surgery: one that underwent negative-pressure wound therapy (NPWT) and another that underwent conventional surgery (CVSG-Posterior debridement, bone grafting, fusion, and internal fixation in one stage). The two groups were compared in terms of the total operation time, total blood loss, total postoperative drainage, postoperative pain score, time for the postoperative erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) to return to normal, postoperative complications, treatment time, and recurrence rate. Results: A total of 43 cases of spinal infection were evaluated, with 19 in the NPWT group and 24 in the CVSG group. The NPWT group had a superior postoperative drainage volume, antibiotic use time, erythrocyte sedimentation rate and CRP recovery times, VAS score at 3 months after the operation, and cure rate at 3 months after operation compared with the CVSG group. There were no significant variations in the total hospital stay and intraoperative blood loss between the two groups. Conclusions: This study supports the use of negative pressure in the treatment of a primary spinal infection and indicates that it has a notably better short-term clinical effect than conventional surgery. Additionally, its mid-term cure rate and recurrence rate are more desirable than those of conventional treatments.

Spinal infection caused by Coxiella burnetii

BACKGROUND

Spinal infection caused by Coxiella burnetii is rare and difficult to diagnose. Here we reported a case of spinal infection from Coxiella burnetii detected by the metagenomic next-generation sequencing (mNGS).

CASE PRESENTATION

A 66-year-old male farmer with no medical history reported severe sharp low back pain, numbness and lower limb weakness for three years. Magnetic resonance imaging (MRI) revealed bone destruction and spinal cord compression within L1 and L2. mNGS testing showed that the inspected specimen collected from spinal lesion was detected positively for Coxiella burnetii. After receiving the combined treatment of antibiotic therapy and surgical intervention, the patient recovered well, and the sagittal MRI showed that vertebral edema signals disappeared and the graft of bone fused 16 months after surgery.

CONCLUSION

The mNGS may be benefit for early diagnosis and intervention of non-specific spinal infection, and future studies should validate its effectiveness for clinical use in spinal infections. Additionally, antibiotic therapy combined with surgical intervention plays an important role on the treatment of spinal infection caused by Coxiella burnetii.

Surgery combined with antibiotics for thoracic vertebral Escherichia coli infection after acupuncture: A case report

BACKGROUND

Acupuncture is relatively popular worldwide, but an unregulated operation can easily lead to infections. The purpose of this report was to analyze a clinical case of surgery combined with the use of antibiotics for the treatment of thoracic vertebral infection by Escherichia coli (E. coli) after acupuncture.

CASE SUMMARY

A 63-year-old male was diagnosed with E. coli infection in the thoracic vertebra after acupuncture. His fever and pain did not improve after treatment with broad-spectrum antibiotics for 10 d. Thus, debridement of the infected area and biopsy were decided. The final pathology confirmed the diagnosis of vertebral infection by E. coli. The patient underwent anterior and posterior thoracic vertebral debridement and internal fixation surgery combined with the use of sensitive antibiotics. He had no fever or backache 3 mo postoperatively.

CONCLUSION

In this report, we first considered antibiotic treatment for the patient with septic spinal infection, but the effect was not obvious. Interventional surgery was combined with the use of sensitive antibiotics to relieve backache, and good clinical results were achieved. Furthermore, acupuncture practitioners should pay attention to hygienic measures.

Spinal infection with intraspinal abscess or empyema and acute myelopathy: comparative analysis of diagnostics, therapy, complications and outcome in primary care

INTRODUCTION

This study on pyogenic spinal infections with intraspinal epidural involvement (PSI +) compared the outcome of patients with spinal cord injury (SCI) to those without (noSCI) taking diagnostic algorithm, therapy, and complications into account.

METHODS

Patients were enrolled in an ambispective study (2012-2017). Diagnostic and therapeutic algorithms, complications, and neurological outcome were analyzed descriptively. Survival was analyzed applying Kaplan-Meier method and Cox regression.

RESULTS

In total, 134 patients with a median (IQR) age of 72 (61-79) years were analyzed. Baseline characteristics were similar between the SCI (n = 55) and noSCI (n = 79). A higher percentage of endocarditis (9% vs. 0%; p = 0.03) was detected in the noSCI group. The majority (81%) received combinatorial therapy including spinal surgery and antibiotic treatment. The surgery complication rate was 16%. At discharge, improvement in neurologic function was present in 27% of the SCI patients. Length of stay, duration of ventilation and the burden of disease-associated complications were significantly higher in the SCI group (e.g., urinary tract infection, pressure ulcers). Lethality risk factors were age (HR 1.09, 95% CI 1.02-1.16, p = 0.014), and empyema/abscess extension (≥ 3 infected spinal segments, HR 4.72, 95% CI 1.57-14.20, p = 0.006), dominating over additional effects of Charlson comorbidity index, SCI, and type of treatment. The overall lethality rate was 11%.

CONCLUSION

PSI + are associated with higher in-hospital mortality, particularly when multiple spinal segments are involved. However, survival is similar with (SCI) or without myelopathy (noSCI). If SCI develops, the rate of disease complications is higher and early specialized SCI care might be substantial to reduce complication rates.

The effectiveness of percutaneous endoscopic lumbar discectomy combined with external lumbar drainage in the treatment of intervertebral infections

Objective

To analyze the effect of percutaneous endoscopic lumbar discectomy in treating lumbar intervertebral infections.

Methods

A total of 13 patients with lumbar intervertebral infections who underwent percutaneous endoscopic lumbar discectomy combined with external drainage between November 2016 and December 2019 were enrolled in the present study. After the operation, sensitive antibiotics were used based on the results of the bacterial culture. If no pathogens were detected in the biopsy culture of the infected tissues, empirical antibiotics were administrated to these patients. The clinical efficacy was evaluated by using a visual analog scale (VAS), Japanese Orthopaedic Association (JOA), Oswestry Disability Index (ODI), and standard Macnab's evaluation. Postoperative computed tomography (CT) and MRI were also used to evaluate clinical efficacy.

Results

The follow-up time was 10–18 months, and the average time was (13.69 ± 2.63) months. Causative bacteria were isolated in 7 of 13 infected tissue biopsy cultures. Systemic antibiotics and anti-tuberculous chemotherapy were administered according to sensitivity studies for identified. There were no pathogens isolated from the other six patients. Empiric antibiotics were administrated in these patients. One week after the operation, WBC, a fractional fraction of medium granulocytes, ESR and CRP were significantly lower compared to before the operation (all P < 0.05). At the last follow-up visit, the above-mentioned markers were all within normal range, which differed compared to the pre-operative data (P < 0.05). The VAS and ODI of the patients at 1 week and 3 months after operation were significantly lower compared to preoperative data (all P < 0.05). During the last follow-up visit, seven patients were excellent, five were good, and one was poor according to standard Macnab's evaluation. No serious complications were recorded.

Conclusions

Percutaneous lumbar discectomy combined with external drainage resulted as an effective method for treating lumbar intervertebral infections and was associated with fewer injuries, less pain, low cost, and low recurrence rate.

Antibiotic-loaded calcium sulfate beads in spinal surgery for patients with spondylodiscitis: a clinical retrospective study

Background

Various surgical techniques for treating spondylodiscitis have been proposed, but the optimal surgical treatment remains controversial. In this study, we propose a new procedure that is implanting antibiotic-loaded calcium sulfate (CS) beads into the disc after debridement using the Quadrant channel combined with percutaneous fixation through a single-stage posterolateral approach for the treatment of spondylodiscitis. Thus, the purpose of this study is to assess the safety and efficacy of this procedure.

Methods

This study collected the data of 32 patients with spine spondylodiscitis and was surgically treated in our department from July 2015 to August 2020. The Demographic data included age, gender, involved segment, and complications were collected. The intra-operative details, results of culture, functional outcome, radiologic outcome, and length of hospital stay, laboratory examination were recorded.

Results

The mean age of the 32 patients was 61.1 ± 9.7 years old. The mean operative time was 135.0 ± 30.6 minutes, and the mean blood loss was 243.4 ± 92.1 ml. The positive rate of culture was 72%. The mean Visual analogue scale (VAS) and Oswestry Disability Index (ODI) score significantly improved from 7.5 to 1.6 and from 65% to 10%. Cobb angle was significantly improved and could be maintained at final follow-up. New bone formation was observed in all patients. There were no recurrences of infection in our study.

Conclusions

The posterolateral debridement and percutaneous fixation combined with antibiotic-loaded calcium sulfate beads filling are effective in the treatment of spondylodiscitis in terms of infection control, early mobilization, and recovery.

Three-Staged Surgical Strategy as a Combined Approach for Multilevel Cervical Pyogenic Spondylodiscitis

Cervical pyogenic spondylodiscitis is rare but can lead to severe clinical problems that often require aggressive surgical treatment for neurological deterioration and life-threatening conditions. Although combined surgical procedures are often utilized to treat multilevel cervical regions, there is a clinical debate regarding the appropriate order and timing of surgeries using the anterior and posterior approaches. Here, we report a case of severe multilevel cervical pyogenic spondylodiscitis treated using a three-staged surgical strategy consisting of cervical laminectomy, posterior fixation, and anterior corpectomy and fusion with an autologous long bone graft; the outcome was quite favorable. Our report demonstrates the safety and usefulness of three-staged surgery in the multilevel cervical region, especially under urgent situations.

Spondylodiscitis treated with freeze-dried bone allograft alone or combined with autograft: A randomized and blinded trial

PURPOSE

To compare the bone fusion of freeze-dried allograft alone versus freeze-dried allograft combined autograft in spinal instrumentation due to spondylodiscitis.

METHODS

A randomized prospective trial of patients with spondylodiscitis treated with surgical debridement and spinal fixation with freeze-dried bone allograft and autograft (Group 1) or freeze-dried bone allograft alone (Group 2) was performed. Patient follow-up was assessed with a CT-scan for bone fusion; consecutive serum inflammatory marker detection (C-reactive protein, [CRP], and erythrocyte sedimentation rate, [ESR]) and clinical assessment (pain, functional disability, and spinal cord injury recovery) were other outcome parameters. The primary outcome was the grade of bone allograft integration with the scale of Tan (which ranges from 1 to 4, with lower scores indicating a better fusion rate) at 1 year after surgery.

RESULTS

A total of 20 patients were evaluated, 13 (65%) men and 7 (35%) women with a mean age of 47.2 (±14.3) years. Homogeneous distribution of demographic data was observed. A similar satisfactory bone graft fusion grade was observed in both graft groups at 1 year after surgery (p = 1.0000). Serum inflammatory markers gradually decreased in both groups after surgical intervention (CRP, p < 0.001; ESR, p < 0.01). At one-year follow-up, gradual improvement of pain, functional disability, and neurological spinal injury recovery in both graft groups were achieved.

CONCLUSION

Freeze-dried allograft alone could be a therapeutic option for spinal fixation surgery due to spondylodiscitis since it achieves a satisfactory graft fusion rate and clinical improvement.

LEVEL OF EVIDENCE

Level 1. Treatment.

REGISTER

NCT03265561.

Independent Reliability Analysis of a New Classification for Pyogenic Spondylodiscitis

STUDY DESIGN

Diagnostic study, level of evidence III.

OBJECTIVE

Pyogenic spondylodiscitis can cause deformity, neurological compromise, disability, and death. Recently, a new classification of spondylodiscitis based on magnetic resonance imaging was published. The objective of this study is to perform an independent reliability analysis of this new classification.

METHODS

We selected 35 cases from our database of different spine centers in Latin America and from the literature; 8 observers evaluated the classification and graded the scenarios according to the methodological grading of the classification developed by Pola et al. Cases were sent to the observers in a random sequence after 3 weeks to assess intraobserver reliability. The interobserver and intraobserver reliabilities were performed with Fleiss and Cohen statistics, respectively.

RESULTS

The overall Fleiss κ value for interobserver agreement was substantial, with 0.67 (95% CI = 0.43-0.91) in the first reading and 0.67 (95% CI = 0.45-0.89) in second reading for the main types of classification. The Cohen κ value for intraobserver agreement was also substantial, with 0.68 (95% CI = 0.45-0.92). The interobserver agreement analysis for the subtypes of this classification was overall substantial, with 0.60 (95% CI = 0.37-0.83) in the first reading and 0.61 (95% CI = 0.41-0.81) in the second reading. The overall intraobserver agreement for subtypes of the classification was also substantial, with 0.63 (95% CI = 0.34-0.93).

CONCLUSION

The new classification developed by Pola et al showed substantial interobserver and intraobserver agreements. More studies are required to validate the usefulness of this classification especially in clinical practice.

Total spine magnetic resonance imaging for detection of multifocal infection in pyogenic spondylodiscitis: a retrospective observational study

BACKGROUND

Due to the unspecific symptoms of spondylodiscitis (SpD), an early radiological examination is necessary. However, controversially discussed is the need for magnetic resonance imaging of the entire spine to exclude multisegmental infections and to determine the required surgical interventions. The aims of this study were to assess the incidence of multilevel non-contiguous pyogenic SpD and compare comorbidities, pain symptoms, and subsequent surgical strategies between unifocal (uSpD) and multifocal (mSpD) SpD.

METHODS

We retrospectively evaluated the data of patients with confirmed, surgically treated, pyogenic SpD who had received a total spine MRI in a single spine center between 2016 and 2018. MRI findings were classified according to Pola-classification and demographics, duration of clinical symptoms (pain and neurology) and Charlson Comorbidity-Index (CCI) results were compared between uSpD und mSpD groups. Surgical therapy was evaluated in patients with mSpD.

RESULTS

uSpD was detected by MRI in 69 of 79 patients (87%). Of these, mSpD was detected in 10 patients (13%) with 21 infected segments (cervical and/ or thoracic and/ or lumbar region). Age and CCI were similar between uSpD and mSpD and 24 of all SpD regions were clinically unapparent. All patients with uSpD were treated operatively. In seven patients with mSpD, all infected levels of the spine were treated surgically in a one-stage procedure; one patient had a two-stage procedure and one patient had surgery at the lumbar spine, and an additional infected segment of the upper thoracic spine was treated conservatively. One patient died before a planned two-stage procedure was performed.

CONCLUSIONS

Due to mSpD being found in approximately 13% of SpD cases, and considering the risk of overlooking an mSpD case, MRI imaging of the total spine is recommended. The detection of multiple infection levels can have an impact on the therapeutic strategy chosen.

Posterior stabilisation without formal debridement for the treatment of non-tuberculous pyogenic spinal infection in frail and debilitated population - A systematic review and meta-analysis

Non-tuberculous pyogenic spinal infection (PSI) incorporates a variety of different clinical conditions. Surgical interventions may be necessary for severe cases where there is evidence of spinal instability or neurological compromise. The primary surgical procedure, for late-stage PSI, focuses on the anterior approach with aggressive debridement of the infected tissue regions. An alternative treatment method that employs a posterior approach without any formal debridement, is seen as controversial. To the best of our knowledge, few case series and no systematic reviews are assessing the value of this posterior technique. We aim to evaluate the effectiveness of the posterior approach without formal debridement and the associated clinical outcomes, for PSI cases requiring surgical intervention. Several databases including MEDLINE, NHS Evidence, and the Cochrane database were searched from the date of creation of each database to December 16, 2019. A selection of the keywords used includes: "posterior approach", "debridement" and "discitis". Studies were excluded if they involved the anterior approach, carried out formal debridement, or were tuberculous spinal infection cases. We accepted any study type which included adult patients, with spinal infection at any level of the vertebral column. The Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guidelines were used to follow standard systematic review structure. The main clinical outcomes evaluated include pain, neurological recovery (Frankel Grading System, FGS) post-operative complications, and functional outcomes (Kirkaldy-Willis Criteria and Spine Tango Combined Outcome Measure Index, COMI). Post-surgical neurological improvement was demonstrated with a mean FGS improvement of 1.12 in 102 patients over the included four articles. Post-operative neurological function was found to be improved at a statistically significant level when a random-effects model was applied, with the effect size found to be at 0.68 (p < 0.001). Pain level was improved significantly postoperatively. There were also enhanced functional outcomes post-intervention when the Kirkaldy-Willis criteria and COMI scores were assessed in certain studies. Within the limit of the available literature, our results showed that the posterior approach with posterior stabilisation without formal debridement can result in successful infection resolution, improved pain scores and neurological outcomes. However, Larger series with longer follow-up duration is strongly recommended.

Spinal Infections: An Update

Spinal infection poses a demanding diagnostic and treatment problem for which a multidisciplinary approach with spine surgeons, radiologists, and infectious disease specialists is required. Infections are usually caused by bacterial microorganisms, although fungal infections can also occur. The most common route for spinal infection is through hematogenous spread of the microorganism from a distant infected area. Most patients with spinal infections diagnosed in early stages can be successfully managed conservatively with antibiotics, bed rest, and spinal braces. In cases of gross or pending instability, progressive neurological deficits, failure of conservative treatment, spinal abscess formation, severe symptoms indicating sepsis, and failure of previous conservative treatment, surgical treatment is required. In either case, close monitoring of the patients with spinal infection with serial neurological examinations and imaging studies is necessary.