Diagnosis, management and outcome of clinically- suspected spinal infection

Pathogen detection in suspected spinal infection: metagenomic next-generation sequencing versus culture

PURPOSE

The aim is to compare the pathogen detection performance of metagenomic next-generation sequencing (mNGS) and the culturing of percutaneous needle biopsy samples obtained from an individual with a suspected spinal infection.

METHODS

A retrospective study of 141 individuals with a suspected spinal infection was conducted, and mNGS was performed. The microbial spectra and detection performance between mNGS and the culturing-based method were compared, and the effects of antibiotic intervention and biopsy on the detection performance were assessed.

RESULTS

The microorganisms isolated most commonly via the culturing-based method were Mycobacterium tuberculosis (n = 21), followed by Staphylococcus epidermidis (n = 13). The most common microorganisms detected via mNGS were Mycobacterium tuberculosis complex (MTBC) (n = 39), followed by Staphylococcus aureus (n = 15). The difference in the type of detected microorganisms between culturing and mNGS was observed only in Mycobacterium (P = 0.001). mNGS helped identify potential pathogens in 80.9% of cases, which was significantly higher than the positivity rate of 59.6% observed for the culturing-based method (P < 0.001). Moreover, mNGS had a sensitivity of 85.7% (95% CI, 78.4% to 91.3%), a specificity of 86.7% (95% CI, 59.5% to 98.3%), and sensitivity gains of 35% (85.7% vs. 50.8%; P < 0.001) during culturing, while no differences were observed in the specificity (86.7% vs. 93.3%; P = 0.543). In addition, antibiotic interventions significantly lowered the positivity rate of the culturing-based method (66.0% vs. 45.5%, P = 0.021) but had no effects on the results of mNGS (82.5% vs. 77.3%, P = 0.467).

CONCLUSION

The use of mNGS could result in a higher detection rate compared to that observed with the culturing-based method in an individual with spinal infection and is particularly valuable for evaluating the effects of a mycobacterial infection or previous antibiotic intervention.

Brucellar, Pyogenic, and Tuberculous Spondylodiscitis at Tertiary Hospitals in Saudi Arabia: A Comparative Retrospective Cohort Study

Introduction

Spondylodiscitis is rare yet the most common form of spinal infection. It is characterized by inflammation of the intervertebral disk space and adjacent vertebral body. In Western countries, the incidence of spondylodiscitis is increasing. Clinical outcomes most commonly reported in the literature are the 1-year mortality rate (range, 6%-12%) and neurologic deficits.

Methods

This multicenter retrospective cohort study assessed patients diagnosed with infectious spondylodiscitis who received treatment at King Abdulaziz Medical City in Riyadh and Jeddah, Saudi Arabia. All enrolled patients were ≥18 years old and were diagnosed per radiologic and microbiological findings and clinical manifestations between January 2017 and November 2021.

Results

This study enrolled 76 patients with infectious spondylodiscitis, with a median age of 61 years. All patients presented with back pain for a median 30 days. Patients were stratified into 3 groups based on the causative pathogen: brucellar spondylodiscitis (n = 52), tuberculous spondylodiscitis (n = 13), and pyogenic spondylodiscitis (n = 11). All laboratory data and biochemical markers were not significantly different. However, C-reactive protein, erythrocyte sedimentation rate, and white blood cells were significantly different in the pyogenic spondylodiscitis group, with medians of 121 mg/dL (P = .03), 82 mmol/h (P = .04), and 11.2 × 109/L (P = .014), respectively.

Conclusions

Back pain is a common clinical feature associated with infectious spondylodiscitis. The immense value of microbiological investigations accompanied with histologic studies in determining the causative pathogen cannot be emphasized enough. Treatment with prolonged intravenous antimicrobial therapy with surgical intervention in some cases produced a cure rate exceeding 60%.

A clinical prediction model to differentiate tuberculous spondylodiscitis from pyogenic spontaneous spondylodiscitis

BACKGROUND

Microbiological diagnosis of tuberculous spondylodiscitis (TS) and pyogenic spontaneous spondylodiscitis (PS) is sometime difficult. This study aimed to identify the predictive factors for differentiating TS from PS using clinical characteristics, radiologic findings, and biomarkers, and to develop scoring system by using predictive factors to stratify the probability of TS.

METHODS

A retrospective single-center study. Demographics, clinical characteristics, laboratory findings and radiographic findings of patients, confirmed causative pathogens of PS or TS, were assessed for independent factors that associated with TS. The coefficients and odds ratio (OR) of the final model were estimated and used to construct the scoring scheme to identify patients with TS.

RESULTS

There were 73 patients (51.8%) with TS and 68 patients (48.2%) with PS. TS was more frequently associated with younger age, history of tuberculous infection, longer duration of symptoms, no fever, thoracic spine involvement, ≥3 vertebrae involvement, presence of paraspinal abscess in magnetic-resonance-image (MRI), well-defined thin wall abscess, anterior subligamentous abscess, and lower biomarker levels included white blood cell (WBC) counts, erythrocyte-sedimentation-rate (ESR), neutrophil fraction, and C-reactive protein (all p < 0.05). Multivariate logistic regression analysis revealed significant predictors of TS included WBC ≤9,700/mm3 (odds ratio [OR] 13.11, 95% confidence interval [CI] 4.23-40.61), neutrophil fraction ≤78% (OR 4.93, 95% CI 1.59-15.30), ESR ≤92 mm/hr (OR 4.07, 95% CI 1.24-13.36) and presence of paraspinal abscess in MRI (OR 10.25, 95% CI 3.17-33.13), with an area under the curve of 0.921. The scoring system stratified the probability of TS into three categories: low, moderate, and high with a TS prevalence of 8.1%, 29.6%, and 82.2%, respectively.

CONCLUSIONS

This prediction model incorporating WBC, neutrophil fraction counts, ESR and presence of paraspinal abscess accurately predicted the causative pathogens. The scoring scheme with combination of these biomarkers and radiologic features can be useful to differentiate TS from PS.

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.

Tuberculosis of the Spine in a Patient With Kidney Cancer

Tuberculosis is a widespread, airborne infectious disease caused by Mycobacterium tuberculosis bacteria. This infection is often misdiagnosed, particularly in the case of spinal tuberculosis which can present atypically. Although rare, tuberculosis can mimic bone tumors or metastatic lesions in the spine. In patients with immunosuppression who have cancer and show signs of lymph node involvement and bone lesions, it is important to explore other potential causes as part of the diagnosis process. Here, we present a case of renal cell carcinoma in which a lytic lesion in the spinal cord was initially misdiagnosed as a metastatic lesion due to the presence of cancer. Skeletal tuberculosis is a rare condition, and it is crucial to maintain a high level of suspicion for a proper diagnosis.

Animal Models for Postoperative Implant‐Related Spinal Infection

Postoperative infections following implant‐related spinal surgery are severe and disastrous complications for both orthopaedic surgeons and patients worldwide. They can cause neurological damage, disability, and death. To better understand the mechanism of these destructive complications and intervene in the process, further research is needed. Therefore, there is an urgent need for efficient, accurate, and easily available animal models to study the pathogenesis of spinal infections and develop new and effective anti‐bacterial methods. In this paper, we provide a general review of the commonly used animal models of postoperative implant‐related spinal infections, describe their advantages and disadvantages, and highlight the significance of correctly choosing the model according to the infection aspect under investigation. These models are valuable tools contributing to the better understanding of postoperative spinal infections and will continue to facilitate the invention of novel preventative and treatment strategies for patients with postoperative spinal infections. However, although they are valid and reproducible in some respects, the current animal models present certain limitations. Future ideal spinal infection animal models may assess the bacterial load of the same animal in real‐time in vivo, and better mimic the human anatomy as well as surgical techniques. Strains other than Staphylococcus aureus account for a large proportion of postoperative spinal infections, and thus, the establishment of models to evaluate other types of microbial infections is expected in the future. Furthermore, novel transgenic models established on advancements in genome editing are also likely to be developed in the future.

Pyogenic and Non-Pyogenic Spinal Infections: Diagnosis and Treatment

Spinal infection (SI) is an infection of vertebral bodies, intervening disc, and/or adjoining para-spinal tissue. It represents less than 10 % of all skeletal infections. There are numerous factors that predispose to developing a SI. Due to the low specificity of signs, delayed diagnosis is common. Hence, SI may be associated with poor outcomes. Diagnosis of SI must be supported by clinicopathological and radiological findings. MRI is a reliable modality of choice. Treatment options vary according to the site of the infection, disease progression, neurology, presence of instability, and general condition of the subject. Conservative treatment (orthosis/ bed-rest + antibiotics) is recommended during the early course with no/ lesser degree of neurological involvement and to medically unfit patients. Nevertheless, when conservative measures alone fail, surgical interventions must be considered. The use of concomitant antimicrobial drugs intravenously during initial duration followed by oral administration is a necessity. Controversies exist regarding the optimal duration of antimicrobial therapy, yet never given less than six weeks. Heterogeneity in clinical picture and associated co-morbidities with a range of treatment modalities are available; however, a common applicable guideline for SI does not exist. Managing SI must be tailored on a case-to-case basis.

Involvement of L5-S1 level as an independent risk factor for adverse outcomes after surgical treatment of lumbar pyogenic spondylitis: A multivariate analysis

PURPOSE

To identify the independent risk factors for adverse outcomes and determine the effect of L5-S1 involvement on the outcome of surgical treatment of lumbar pyogenic spondylitis (PS).

METHODS

A retrospective analysis was performed for all consecutive patients who underwent surgery for lumbar PS between November 2004 and June 2020 at a single institution. The patients were divided into two groups based on the outcomes: good and adverse (treatment failure, relapse, or death). Treatment failure was defined as persistent or worsening pain with C-reactive protein (CRP) reduction less than 25% from preoperative measurement or requiring additional debridement. Relapse was defined as the reappearance of symptoms and signs with an elevated white blood cell count, erythrocyte sedimentation rate, and CRP after the first period of treatment. Binary logistic regression analyses were performed to identify the independent risk factors for adverse outcomes.

RESULTS

Twenty-four (21.2%) of the 113 patients were classified as having adverse outcomes: treatment failure, relapse, and death occurred in 15, 7, and 2 patients, respectively. The involvement of L5-S1 (adjusted odds ratio [aOR] = 6.561, P = 0.004), Methicillin-resistant Staphylococcus aureus (MRSA) infection (aOR = 6.870, P = 0.008), polymicrobial infection (aOR = 12.210, P = 0.022), and Charlson comorbidity index (CCI; P = 0.005) were identified as significant risk factors for adverse outcomes.

CONCLUSION

Involvement of L5-S1, MRSA, polymicrobial infection, and CCI were identified as independent risk factors for adverse outcomes after surgical treatment of lumbar PS. Because L5-S1 is anatomically demanding to access anteriorly, judicious access and thorough debridement are recommended in patients requiring anterior debridement of L5-S1.

Simultaneous determination of three antituberculosis drugs in the serum of patients with spinal tuberculosis by capillary electrophoresis

The pharmacokinetic variations of a single drug in an antituberculosis regimen are associated with acquired drug resistance and therapy failure. This study aimed to develop a simple and effective method for monitoring the serum levels of isoniazid (INH), rifampicin (RFP), and pyrazinamide (PZA), three antibiotics used in patients with spinal tuberculosis using capillary electrophoresis (CE). A standard solution of INH, RFP, and PZA was prepared and mixed with serum to prepare the standard curve. The detection limit, quantification limit, precision, stability, repeatability, and sample recovery were determined. Then, INH, RFP, and PZA were measured from the leftover serum samples of all patients with spinal tuberculosis who were treated with 2SHRZ/2.5H2R2Z2 combined with surgery in a tertiary hospital in Qinghai from October 2015 to September 2017. A total of 107 patients with spinal tuberculosis treated using the 2SHRZ/2.5H2R2Z2 regimen combined with surgery were included in this study. All three antibiotics had linear standard curves with high correlation coefficients (R² = 0.9997, 0.9994, and 0.9986). The recovery rates were 98.1% for INH, 96.5% for PZA, and 97.2% for RFP. The results from the serum samples showed that the plasma concentrations of INH (4.989 ± 1.692 μg mL^-1) and RFP (9.400 ± 1.711 μg mL^-1) reached effective therapeutic concentrations in all patients, but not PZA (33.860 ± 1.830 μg mL^-1). The CE method for measuring INH, RFP, and PZA simultaneously in serum samples of patients with spinal tuberculosis is simple, rapid, and sensitive. This method is suitable for the routine monitoring of INH, RFP, and PZA concentrations in the serum of patients with spinal tuberculosis.

Conservative versus operative management of postoperative lumbar discitis

Background:

Treatment option of postoperative discitis (POD) is either conservative or operative, but till date, there are no established validated protocols of the treatment of postoperative lumbar discitis.

Aim:

The aim of this study was to assess the outcome of conservative versus operative management of POD following single-level lumbar discectomy.

Methods:

We prospectively studied a total of 38 cases of POD. The patients were diagnosed clinically, radiologically, and by laboratory investigations and followed up with serial erythrocyte sedimentation rate (ESR), C-reactive protein, X-ray, computed tomography (CT), and magnetic resonance imaging. Demographic data, clinical variables, length of hospital stay, duration of antibiotic treatment, and posttreatment complications were collected, and pre- and postoperative assessment was done using the Visual Analog Scale (VAS) and Japanese Orthopaedic Association (JOA) score. Functional outcome of the study was measured by the modified criteria of Kirkaldy–Willis.

Results:

VAS score for pain was significantly decreased in both groups after treatment. However, posttreatment differences were not statistically significant. In posttreatment mean JOA score, differences were not statistically significant in both groups except the mean difference (−0.47) of restriction of daily activities, which was statistically significant (95% confidence interval: −0.88–−0.07, P = 0.025, unpaired t-test). About 73.7% and 84.2% of the patients had a satisfactory functional outcome in conservative and operative management groups, respectively, at the end of 12-month follow-up.

Conclusions:

Operative management yielded better outcomes than traditional conservative treatment in terms of functional outcomes, length of hospital stays, and duration of antibiotic treatment as determined by both the pain and daily activity levels.

Bone and joint tuberculosis in patients undergoing dialysis: clinical features, risk factors, and outcomes in 17 patients

OBJECTIVE

This study was performed to investigate the clinical features, risk factors, and outcomes of bone and joint tuberculosis in patients undergoing dialysis.

METHODS

We systematically reviewed the medical records of 17 patients with bone and joint tuberculosis undergoing dialysis who were admitted to our hospital from January 2009 to January 2019.

RESULTS

Seventeen patients with bone and joint tuberculosis undergoing dialysis were identified in this retrospective study, and 13 patients were undergoing hemodialysis. The mean age of the 17 patients was 61.3 years (range, 32-82 years), and 10 (58.9%) patients were male. Most of the patients had a low CD4+ cell count and low hemoglobin and albumin levels. Surgery was performed in 6 patients (35.3%), and 13 of the 17 patients (76.4%) were cured. Three patients had bone or spine sequelae, mainly because of a delayed diagnosis, and one patient died of heart failure.

CONCLUSION

These findings indicate that older age, a low CD4+ cell count, and low hemoglobin and albumin levels are possible risk factors for bone and spine tuberculosis in patients undergoing dialysis. If diagnosed early, most patients should have a good outcome after anti-tubercular therapy with or without surgery.

How is the microbial diagnosis of bacterial vertebral osteomyelitis performed? An 11-year retrospective study

Vertebral osteomyelitis (VOM) is often diagnosed with delays, resulting in poorer outcomes. Microbial documentation is particularly challenging and obtained using blood cultures (BCs) and vertebral biopsies (VBs; CT-guided or surgical). We retrospectively analysed VOM cases in a tertiary reference centre between 2004 and 2015, focusing on how and how quickly microbiological diagnosis was performed. Among 220 VOM, 88.2% had documentation, including Gram-positive cocci (GPC) (70.6%), Gram-negative rods (GNR) (9.3%), anaerobes (3.6%), polybacterial infections (6.7%) and tuberculosis (9.8%). BCs were performed in 98.2% and positive in 59.3%, identifying most GPC (80.3%) and half of GNR (54.6%). VBs were performed in fewer cases (37.7%), but were more frequently positive (68.8% for CT-guided and 81.0% for surgical biopsies). They documented all anaerobes (100.0%), most M. tuberculosis (84.2%) and polybacterial infections (76.9%), and GNR (45.4%). Extra-vertebral samples highly contributed to tuberculosis diagnosis (52.6%, and 15.8% as the only positive sample). Documentations most often followed radiological diagnosis (53.4%). They were obtained earlier by BCs than by VB after first clinical symptoms (median of 14 versus 51 days). Antibiotic treatments were mostly initiated after samplings (88.0%). BCs allow the documentation of most VOM and should be performed without delay in case of clinical or radiological suspicion; however, they may miss 1 out of 5 GPC and 1 out of 2 GNR. VBs have a higher positivity rate and should be rapidly performed if negative BCs. It is likely that delayed and missed diagnoses result from the insufficient use of VB.

Management of Pyogenic Spinal Infection, review of literature

Objective

To evaluate the available evidence for the management of Pyogenic Spinal Infection (PSI).

Methods and results

A comprehensive search for the relevant literature published between 1990 and 2018 to evaluate the management of PSI was conducted.Nonoperative management of carefully selected patients for an adequate duration of antibiotics can result in satisfactory outcomes with low recurrence rate. When there is an indication for surgery, posterior approach, with or without debridement of infected tissue reported to be associated with good outcomes.

Conclusion

Studies with larger sample sizes and longer duration of follow up are recommended to formulate more comprehensive evidence.

Joint EANM/ESNR and ESCMID-endorsed consensus document for the diagnosis of spine infection (spondylodiscitis) in adults

PURPOSE

Diagnosis of spondylodiscitis (SD) may be challenging due to the nonspecific clinical and laboratory findings and the need to perform various diagnostic tests including serologic, imaging, and microbiological examinations. Homogeneous management of SD diagnosis through international, multidisciplinary guidance would improve the sensitivity of diagnosis and lead to better patient outcome.

METHODS

An expert specialist team, comprising nuclear medicine physicians appointed by the European Association of Nuclear Medicine (EANM), neuroradiologists appointed by the European Society of Neuroradiology (ESNR), and infectious diseases specialists appointed by the European Society of Clinical Microbiology and Infectious Diseases (ESCMID), reviewed the literature from January 2006 to December 2015 and proposed 20 consensus statements in answer to clinical questions regarding SD diagnosis. The statements were graded by level of evidence level according to the 2011 Oxford Centre for Evidence-based Medicine criteria and included in this consensus document for the diagnosis of SD in adults. The consensus statements are the result of literature review according to PICO (P:population/patients, I:intervention/indicator, C:comparator/control, O:outcome) criteria. Evidence-based recommendations on the management of adult patients with SD, with particular attention to radiologic and nuclear medicine diagnosis, were proposed after a systematic review of the literature in the areas of nuclear medicine, radiology, infectious diseases, and microbiology.

RESULTS

A diagnostic flow chart was developed based on the 20 consensus statements, scored by level of evidence according to the Oxford Centre for Evidence-based Medicine criteria.

CONCLUSIONS

This consensus document was developed with a final diagnostic flow chart for SD diagnosis as an aid for professionals in many fields, especially nuclear medicine physicians, radiologists, and orthopaedic and infectious diseases specialists.

Evaluation of Challenges in Diagnosis of Spontaneous Subacute Pyogenic Spondylodiscitis in Immunocompetent Patients: Experiences from a Tertiary Care Center

Study Design

Prospective clinical study.

Purpose

We evaluated the challenges faced during diagnosis and management of patients with subacute pyogenic discitis and discussed various clues in clinical history, radiologic and hematologic parameters of these patients that helped in establishing their diagnosis.

Overview of Literature

Present literature available shows that in patients with subacute spondylodiscitis and infection with less virulent organisms, the clinical picture often is confusing and the initial radiologic and hematologic studies do not contribute much toward establishing the diagnosis.

Methods

Demographic pattern, predisposing factors, clinical presentation, comorbidities, microbiology, treatment, neurologic recovery, and complications of 11 patients were prospectively reviewed regarding their contribution toward the conformation of diagnosis of subacute pyogenic discitis.

Results

Mean age at presentation was 46.0 years with average preoperative Oswestry Disability Index and Visual Analog Scale scores of 83.4 and 7.18, respectively. Mean follow-up duration was 12.0 months. The most common site of infection was the lumbar spine, followed by the thoracic spine (n=1). Infective organisms were isolated in only 45% of cases. Staphylococcus aureus was the most common causative organism isolated.

Conclusions

Diagnosing subacute spondylodiscitis in a patient presenting with subacute low backache poses a diagnostic challenge. Clinical and radiologic picture are deceiving, and bacteriologic results often are negative, further complicating the picture. A detailed medical history along with clinical, radiologic, and biochemical parameters prevents missing the diagnosis. Serial serum Creactive protein and alkaline phosphatases were more reliable blood parameters in cases of subacute presentation.

Selection of an appropriate empiric antibiotic regimen in hematogenous vertebral osteomyelitis

Background

Empiric antibiotic therapy for suspected hematogenous vertebral osteomyelitis (HVO) should be initiated immediately in seriously ill patients and may be required in those with negative microbiological results. The aim of this study was to inform the appropriate selection of empiric antibiotic regimens for the treatment of suspected HVO by analyzing antimicrobial susceptibility of isolated bacteria from microbiologically proven HVO.

Method

We conducted a retrospective chart review of adult patients with microbiologically proven HVO in five tertiary-care hospitals over a 7-year period. The appropriateness of empiric antibiotic regimens was assessed based on the antibiotic susceptibility profiles of isolated bacteria.

Results

In total, 358 cases of microbiologically proven HVO were identified. The main causative pathogens identified were methicillin-susceptible Staphylococcus aureus (33.5%), followed by methicillin-resistant S. aureus (MRSA) (24.9%), Enterobacteriaceae (19.3%), and Streptococcus species (11.7%). Extended spectrum β-lactamase (ESBL)-producing Enterobacteriaceae and anaerobes accounted for only 1.7% and 1.4%, respectively, of the causative pathogens. Overall, 73.5% of isolated pathogens were susceptible to levofloxacin plus rifampicin, 71.2% to levofloxacin plus clindamycin, and 64.5% to amoxicillin-clavulanate plus ciprofloxacin. The susceptibility to these oral combinations was lower in cases of healthcare-associated HVO (52.6%, 49.6%, and 37.6%, respectively) than in cases of community-acquired HVO (85.8%, 84.0%, and 80.4%, respectively). Vancomycin combined with ciprofloxacin, ceftriaxone, ceftazidime, or cefepime was similarly appropriate (susceptibility rates of 93.0%, 94.1%, 95.8%, and 95.8%, respectively).

Conclusions

Based on our susceptibility data, vancomycin combined with a broad-spectrum cephalosporin or fluoroquinolone may be appropriate for empiric treatment of HVO. Fluoroquinolone-based oral combinations may be not appropriate due to frequent resistance to these agents, especially in cases of healthcare-associated HVO.

Clinical Characteristics and Outcomes of Patients with Culture-Negative Pyogenic Spondylitis according to Empiric Glycopeptide Use

Background

The optimal choice of antibiotics is challenging in culture-negative pyogenic spondylitis (PS). The empiric use of glycopeptides is suggested depending on various risk factors, although clinical data are sparse. This study aimed to analyze the clinical characteristics and outcomes of patients with culture-negative PS and evaluate the effect of empiric glycopeptide use on clinical outcomes in these patients.

Materials and Methods

Data on the characteristics, treatment, and outcomes of 175 patients diagnosed with PS were retrospectively obtained from the electronic database of a tertiary referral hospital from 2009 to 2016. Patients with negative culture results were grouped by the duration of glycopeptide treatment: glycopeptide therapy <28 days (Group A) and glycopeptide therapy ≥28 days (Group B).

Results

Of 89 patients with negative culture results, 78 were included in the analysis (Group A, n = 66; Group B, n = 12). The mean age of patients with negative culture results was 65.5 years, and 52.6% were male. The median follow-up duration was 573 (interquartile range [IQR], 83 – 1,037) days. The duration of intravenous glycopeptide therapy was 0.0 (IQR, 0.0 – 0.0) days and 55.5 (IQR, 37.0 – 75.7) days for Groups A and B, respectively. Patients who used glycopeptide longer empirically (Group B) had more commonly undergone a previous spinal procedure, including surgery (P = 0.024). The length of hospitalization, erythrocyte sedimentation rate, and C-reactive protein level were significantly higher in Group B compared with those in Group A (P <0.001, P <0.001, and P = 0.006, respectively). Regarding treatment modalities, patients in Group B underwent surgery more frequently (P = 0.017). The duration of parenteral antibiotic treatment was longer in Group B (P <0.001). Recurrence was noted in 7 patients (9.0%), and the recurrence rate was not significantly different between the 2 groups (Group A, 5/66 [7.6%]; Group B, 2/12 [16.7%]; P = 0.293).

Conclusion

The recurrence rate among patients with culture-negative PS was not different based on the duration of empiric glycopeptide use. However, considering the small sample size and heterogeneity of our study population, we suggest that it is reasonable to administer glycopeptide antibiotics in these patients depending on clinical risk factors. Further large-scale prospective studies are needed to obtain more evidence for appropriate antibiotic treatment.

Percutaneous endoscopic debridement and irrigation for thoracic infections

OBJECTIVE

To investigate the safety and efficacy of percutaneous endoscopic debridement and irrigation for thoracic infections and to make an appropriate choice according to the patient's condition.

METHODS.

Thirty patients with thoracic infections who received surgical treatment from August 2014 to December2016 were retrospectively analyzed. There were 16 males and 14 females, aged from 41 to 90 years, with an average of 64.4 years. A total of 9 cases were treated with percutaneous endoscopic debridement and irrigation (minimal group), and 21 cases were treated with open debridement in combination with pedicle screw fixation (conventional group). Patients underwent follow-up for 1 month. General condition, operative index, laboratory results, and imaging features were recorded.

RESULTS.

Compared with the conventional group, there were more comorbidities in patients in the minimal group (8 cases in the minimal group, 10 cases in the conventional group, P=0.049), shorter hospital stay (10.1 + 2.26 days in the minimal group, 16.1 + 6.81 days in the conventional group, P=0.016), less bleeding volume (383.3 + 229.86ml in the minimal group, 90 + 11.18ml in the conventional group, P=0.000), lower VAS score at discharge (2.9 + 0.93 in the minimal group, 3.9 + 0.91 in the conventional group, P=0.013). There was no spinal instability case in the minimal group, 10 cases in the conventional group, P=0.013. There were significant differences. The C reaction protein prior to operation in the minimal group was 28.4±7.50mg/L. Compared with 45.1 + 15.78mg/L in the conventional group, P=0.005, it was lower.

CONCLUSIONS.

Percutaneous endoscopic debridement and irrigation are an effective surgery for treatment of thoracic infections, especially suitable for patients with comorbidities and poor general condition. However, for severe infection and spinal instability, we tend to choose open surgery in combination with fixation.

Propionibacterium acnes infections in patients with idiopathic scoliosis: a case-control study and review of the literature

PURPOSE

Surgical site infection (SSI) caused by Propionibacterium acnes is an infrequent but devastating complication after spinal fusion. The purpose of this study was to identify risk factors for SSI with Propionibacterium acnes after spinal fusion for juvenile and adolescent idiopathic scoliosis (JIS and AIS).

METHODS

A case-control study was performed. Each case was matched 2:1 for age, gender and diagnosis. Retrospective chart review was performed to obtain relevant demographic, surgical and clinical data for all cases and controls. Statistical analysis included paired t-test and McNemar test, as well as exact logistic regression and robust regression models.

RESULTS

This study included ten infection cases (eight AIS, two JIS) and 20 controls (16 AIS, four JIS). In total, six infected cases presented within two weeks of the index procedure (acute infection) and four infected cases presented more than one year from the index procedure (delayed infection). The most common presentation for acute infections was wound drainage, while back pain was more common in delayed infections. All infections were successfully treated with surgical irrigation and debridement and postoperative antibiotics. Hardware was removed for patients with delayed infections. The strongest risk factor for infection was increased requirement for blood transfusion, but it did not reach statistical significance.

CONCLUSION

SSI with Propionibacterium acnes is an important complication after spinal fusion for idiopathic scoliosis. These infections can be successfully treated, but larger studies are needed to further identify risk factors and establish standardized guidelines for the treatment and prevention of this complication.

Delays in the diagnosis and treatment of bone and joint tuberculosis in the United Kingdom

Aims

Tuberculosis (TB) infection of bones and joints accounts for 6.7% of TB cases in England, and is associated with significant morbidity and disability. Public Health England reports that patients with TB experience delays in diagnosis and treatment. Our aims were to determine the demographics, presentation and investigation of patients with a TB infection of bones and joints, to help doctors assessing potential cases and to identify avoidable delays.

Patients and Methods

This was a retrospective observational study of all adults with positive TB cultures on specimens taken at a tertiary orthopaedic centre between June 2012 and May 2014. A laboratory information system search identified the patients. The demographics, clinical presentation, radiology, histopathology and key clinical dates were obtained from medical records.

Results

A total of 31 adult patients were identified. Their median age was 37 years (interquartile range (IQR): 29 to 53); 21 (68%) were male; 89% were migrants. The main sites affected were joints (10, 32%), the spine (8, 26%) and long bones (6, 19%); 8 (26%) had multifocal disease. The most common presenting symptoms were pain (29/31, 94%) and swelling (26/28, 93%). ‘Typical’ symptoms of TB, such as fever, sweats and weight loss, were uncommon. Patients waited a median of seven months (IQR 3 to 13.5) between the onset of symptoms and referral to the tertiary centre and 2.3 months (IQR 1.6 to 3.4.)) between referral and starting treatment. Radiology suggested TB in 26 (84%), but in seven patients (23%) the initial biopsy specimens were not sent for mycobacterial culture, necessitating a second biopsy. Rapid Polymerase Chain Reaction-based testing for TB using Xpert MTB/RIF was performed in five patients; 4 (80%) tested positive for TB. These patients had a reduced time between the diagnostic biopsy and starting treatment than those whose samples were not tested (median eight days versus 36 days, p = 0.016).

Conclusion

Patients with bone and joint TB experience delays in diagnosis and treatment, some of which are avoidable. Maintaining a high index of clinical suspicion and sending specimens for mycobacterial culture are crucial to avoid missing cases. Rapid diagnostic tests reduce delays and should be performed on patients with radiological features of TB. Cite this article: Bone Joint J 2018;100-B:119–24.

Decompression alone versus fusion for pyogenic spondylodiscitis

BACKGROUND CONTEXT

A spinal infection is a serious problem for a spine surgeon, and there is currently much debate regarding how best to treat pyogenic spondylodiscitis using antibiotics and the instrumentations that have been developed to date.

PURPOSE

The purpose of this study was to determine which method is better for treating pyogenic spondylodiscitis.

STUDY DESIGN

A retrospective chart review was performed.

PATIENT SAMPLE

Thirty-one patients with pyogenic spondylodiscitis underwent surgical treatment between 2000 and 2016 at the authors' institution.

OUTCOME MEASURES

Clinical outcomes were assessed using a visual analog scale (VAS). We measured translation and rotation on flexion and extension X-rays to identify instability.

METHODS

Patients were divided into two groups: Group I, decompression group; Group II, decompression plus fusion group. Group I exhibited no instability according to a preoperative radiographic study, whereas Group II exhibited instability. Both groups were compared with respect to demographics and laboratory findings, including tests to determine C-reactive protein (CRP) levels and erythrocyte sedimentation rates (ESR), organisms, and the total duration of antibiotic treatment after the operation. We compared the results of the preoperative, postoperative, and last follow-up radiographic examinations of the sagittal alignment of the infected segment. This study was supported by a clinical research fund (4,500 dollars) from the National Health Insurance Service, Ilsan Hospital.

RESULTS

A total of 31 patients were included; 22 (71%) were in Group I and 9 (29%) were in Group II. On radiological examination, the mean preoperative translation and rotation values in Group I were 2.45±1.22 mm and 5.64±1.98°, and in Group II were 5.35±1.65 mm and 12.01±4.22°. At the last follow-up, the mean translation and rotation values in Group I were 1.95±1.75 mm and 2.69±1.61°, and in Group II were 1.77±1.02 mm and 3.44±2.07°. Both Groups I and II exhibited stability after the operation. No differences were detected in preoperative ESR and CRP levels between the two groups. Group I, compared with Group II, experienced a shorter duration of treatment with antibiotics and normalization of ESR and CRP levels after the operation and a shorter hospitalization period.

CONCLUSIONS

If the appropriate antibiotics are administered quickly when there is no instability, decompression alone is effective; however, if instability is detected, decompression plus fusion can be used to achieve stability.

Pyogenic Vertebral Osteomyelitis: Clinical Features, Diagnosis, and Treatment

Pyogenic vertebral osteomyelitis (PVO) may result in neurological deficits and sequelae, so early diagnosis and appropriate treatment are critical. Many previous studies on PVO exist, but our paper has aimed to comprehensively summarize the clinical aspects of PVO. Through review of the vast literature on the clinical research of PVO an overview of the clinical characteristics, diagnostic methods, treatment and prognosis is provided.

Cervical Spondylitis and Epidural Abscess Caused by Brucellosis: a Case Report and Literature Review

Brucellosis is a zoonotic disease widely seen in endemic regions and that can lead to systemic involvement. The musculoskeletal system is frequently affected, and the disease can exhibit clinical involvements such as arthritis, spondylitis, spondylodiscitis, osteomyelitis, tenosynovitis and bursitis. Spondylitis and spondylodiscitis, common complications of brucellosis, predominantly affect the lumbar and thoracic vertebrae. Epidural abscess may occur as a rare complication of spondylitis. Spinal brucellosis and development of epidural abscess in the cervical region are rare. Development of epidural abscess affects the duration and success of treatment. Spinal brucellosis should be considered in patients presenting with fever and lower back-neck pain in endemic regions, and treatment must be initiated with early diagnosis in order to prevent potential complications.

Diagnosis and treatment of nonadjacent cryptococcal infections at the L1 and S1 vertebrae

Cryptococcal spine infections are rare infections that are easy to misdiagnose and difficult to cure. Therefore, we report the case of a 25-year-old man who presented with nonspecific spinal lesions at L1 and S1. The patient underwent surgical removal of the lesions, and specimens were submitted for microbial identification, which identified a cryptococcal infection that was susceptible to amphotericin B. The patient exhibited marked improvement after receiving intravenous amphotericin B and remained asymptomatic (no back pain, fever, or other symptoms) at the 3‑ and 9‑month follow-ups. Similar cases of cryptococcal spine infections are rare, and we believe that our diagnostic findings and treatment experience may help improve the management of this rare disease.

Reduced ability to work both before and after infectious spondylodiscitis in working-age patients

BACKGROUND

As little is known about the ability to work in patients with infectious spondylodiscitis, we compared the relation between the workforce before infection with that of a reference population and described the patients' ability to work after infection including predictors of return to work (RTW).

METHODS

We identified all patients aged 20-57 years treated for infectious spondylodiscitis January 1994-May 2009 at hospitals in Funen County, Denmark. The work status of each week from 2 years before until 2 years after index date was compared with that of a reference population. Time to RTW was described using cumulative incidence curves and univariate cause-specific Cox-regression analyses (hazard ratios - HRs).

RESULTS

Of 112 identified patients, 8 (7%) died within the first year and 48 (43%) were part of the workforce 1 year before index. Through the entire observation period, the patients had lower affiliation to the workforce compared with the reference population. During the observation period, the proportion of patients on permanent disability pension increased from 24% to 38% and the proportion of self-supporters decreased from 58% to 33%. Seventy-three per cent of the patients being part of the workforce 1 year before index returned to the workforce within the 2 year follow-up. Main predictor of RTW was being part of the workforce 1 year before index (HR = 7.8; CI: 2.4-25.3).

CONCLUSIONS

Patients with infectious spondylodiscitis were less likely to be part of the workforce before infection compared with a reference population and infection further lowered their ability to RTW.

Diagnostic yield of computed tomography-guided bone biopsy and clinical outcomes of tuberculous and pyogenic spondylitis

BACKGROUND/AIMS

This study aimed to evaluate the efficacy of computed tomography (CT)-guided bone biopsy for the diagnosis of spinal infection and compared the clinical outcomes between tuberculous and pyogenic spinal infections.

METHODS

The retrospective cohort study included patients who received CT-guided bone biopsy at a tertiary hospital over the 13 years.

RESULTS

Among 100 patients, 67 had pyogenic spondylitis and 33 had tuberculous spondylitis. Pathogens were isolated from bone specimens obtained by CT-guided biopsy in 42 cases, with diagnostic yields of 61% (20/33) for tuberculous spondylitis and 33% (22/67) for pyogenic spondylitis. For 36 culture-proven pyogenic cases, Staphylococcus aureus was the most commonly isolated organism. Patients with pyogenic spondylitis more frequently presented with fever accompanied by an increase in inflammatory markers than did those with tuberculosis. Among all patients who underwent surgery, the incidence of late surgery performed one month after diagnosis was higher in patients with tuberculous infection (56.3%) than in those with pyogenic disease (23.3%, p = 0.026).

CONCLUSIONS

Results obtained by CT-guided bone biopsy contributed to prompt diagnoses of spinal infections, especially those caused by tuberculosis. Despite administration of anti-tuberculous agents, patients with tuberculous spondylitis showed an increased tendency to undergo late surgery.

The Etiology, Clinical Presentation and Long-term Outcome of Spondylodiscitis in Children

BACKGROUND

Spondylodiscitis (SD) is a rare disease in children and diagnosis can be delayed because of the scarcity in incidence and lack of awareness. The purpose of this study was to evaluate and report the microbiologic epidemiology and clinical features of pediatric SD in South Korea.

METHODS

This was a retrospective study of children <19 years old admitted for the treatment of SD between 2000 and 2014. Electronic medical records were reviewed for clinical parameters and etiologic agents.

RESULTS

During the 15-year period, 25 patients were diagnosed with SD. The median age was 13.8 years, and 60% were male. Back pain was the most common presenting symptom (n = 17; 68%), and only 52% (n = 13) of the patients had a history of fever (≥38.0°C). In patients younger than 3 years, irritability (n = 5; 62.5%) was the most predominant symptom. Microorganisms were isolated in 22 cases, the most common being Staphylococcus aureus (40%) and Mycobacterium tuberculosis (32%). Of the 25 patients, 64% (n = 16) had blood cultures taken, 56% (n = 14) underwent percutaneous fluoroscopy-guided biopsy, and 48% (n = 12) underwent open surgical biopsy. The positive rate for microbiologic diagnosis of each method was 18.8% (n = 3) for blood culture, 71.4% (n = 10) for percutaneous biopsy and 100% (n = 12) for surgical biopsy. Overall, 52% (n = 13) needed surgical treatment along with antibiotic therapy. Patients who needed surgery had a significant delay in diagnosis compared with those that did not (median, 60 vs. 31 days; P = 0.014).

CONCLUSIONS

S. aureus and M. tuberculosis are the predominant causes of SD in children in South Korea. Obtaining tissue culture is important to confirm the bacterial etiology of the infection and appropriately guide antibiotic therapy in a community in which the endemic organisms require treatment pathways that are widely divergent.

Susceptibility Pattern of Microorganisms Isolated by Percutaneous Needle Biopsy in Nonbacteremic Pyogenic Vertebral Osteomyelitis

Pyogenic vertebral osteomyelitis (VO) is diagnosed according to several lines of evidence: clinical, biological, radiological, and histological. Definitive diagnosis requires the isolation of a causative pathogen or histological confirmation. The aim of our study was to describe the microorganisms isolated by percutaneous needle biopsy (PNB) and to analyze their susceptibility patterns, in order to assess the possibility of empirical combination therapy for the treatment of nonbacteremic patients without resorting to PNB. Based on a French prospective multicenter study of 351 patients with VO, we compiled clinical, biological, and radiological findings for 101 patients with microbiologically confirmed VO. Based on antibiotic susceptibility testing of PNB isolated pathogens, the suitabilities of four antibiotic combinations were analyzed: ofloxacin plus rifampin, levofloxacin plus rifampin, ciprofloxacin plus clindamycin, and ciprofloxacin plus amoxicillin-clavulanate. The main causative pathogens identified were coagulase-negative Staphylococcus spp. (26% of isolates), followed by Staphylococcus aureus (21%), Streptoccocus spp. (13%), and enterobacteria (21%). Empirical antibiotic combination therapy was effective in nearly 75% of cases, and the different combinations gave similar results, except for ofloxacin-rifampin, which was effective in only 58% of cases. A "perfect" empirical antibiotic therapy does not exist. If PNB is not possible, a combination of a fluoroquinolone with clindamycin or rifampin can be used, but the high risk of microbiological failure does not allow the exclusion of PNB. (This study has been registered with EudraCT, number 2006-000951-18, and ClinicalTrials.gov, number NCT00764114.).

Clinical Value of Procalcitonin in Patients with Spinal Infection

Objective

This study was designed to evaluation the diagnostic value of procalcitonin (PCT) in patients with spinal infection, compare to the classical biomarkers such as C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), white blood cell (WBC) count.

Methods

All patients who were diagnosed as a spinal infection between January, 2013 and July, 2014 were included in this study. Serum PCT, CRP, ESR, and WBC count were checked at initial hospital visit and once a week serially until they were discharged. Patient's medical history, causes and pathogens of spinal infection were reviewed.

Results

Total 34 (16 men, 18 women) patients were included in this study. Mean age of the patients was 65.6 year-old. Causes of spinal infection were pain block procedure (14, 41.2%) and post-operation (5, 14.7%). Out of 25 patients who showed elevated initial serum PCT level, 20 patients (80%) had a combined systemic infection. 14 patients (6.7%) had a sepsis, 3 patients (14.2%) had a urinary tract infection and 2 (9.6%) had a pneumonia. 14 patients (41.2%) showed elevation of serum PCT level during treatment. Among them, 9 patients (64.3%) had a combined infection such as sepsis and urinary tract infection.

Conclusion

Serum CRP showed more sensitivity compared to serum PCT in patients with spinal infection. Patients with spinal infection who showed elevated serum PCT level should be investigated for combined infection and proper antibiotics should be applied.

Differential diagnosis between tuberculous spondylodiscitis and pyogenic spontaneous spondylodiscitis: a multicenter descriptive and comparative study

BACKGROUND CONTEXT

Although tuberculous and pyogenic spondylodiscitis are common causes of spinal infections, their protean manifestation complicates differential diagnosis.

PURPOSE

The clinical, laboratory, and radiologic characteristics of tuberculous and pyogenic spontaneous spondylodiscitis were compared in this study.

STUDY DESIGN

This multicenter retrospective study was conducted in 11 teaching hospitals in the Republic of Korea from January 2011 to December 2013.

PATIENT SAMPLE

Study subjects included adult patients (≥18 years) diagnosed with tuberculous (n=60) or pyogenic (n=117) spontaneous spondylodiscitis.

OUTCOME MEASURES

Risk factors for tuberculous spondylodiscitis were determined, and their predictive performance was evaluated.

METHODS

Multivariate logistic regression analysis was performed to determine predictors independently associated with tuberculous spondylodiscitis. Receiver-operating characteristic curve analysis using the presence or absence of risk factors was used to generate a risk index to identify patients with increased probability of tuberculous spondylodiscitis.

RESULTS

Of 177 patients, multivariate logistic regression analysis showed that patients with tuberculous spondylodiscitis (n=60) were more frequently women, with increased nonlumbar spinal involvement and associated non-spinal lesions, delayed diagnosis, higher serum albumin levels, reduced white blood cell counts, and lower C-reactive protein and procalcitonin levels. Among 117 patients with pyogenic spondylodiscitis, the most frequent causative microorganism was Staphylococcus aureus (64.1%). The mean diagnostic delay was significantly shorter, which may reflect higher clinical expression leading to earlier diagnosis. A combination of clinical data and biomarkers had better predictive value for differential diagnosis compared with biomarkers alone, with an area under the curve of 0.93, and sensitivity, specificity, and positive and negative predictive values of 95.0%, 79.5%, 70.4%, and 96.9%, respectively.

CONCLUSIONS

This study provides guidance for clinicians to predict the causative organisms of spondylodiscitis in uncertain situations and before culture or pathologic examinations. Clinical data and single biomarkers combined can be useful for differential diagnoses between tuberculous and pyogenic spondylodiscitis.

A Retrospective Analysis of the Management of Postoperative Discitis: A Single Institutional Experience

Study Design

Retrospective study.

Purpose

The aim of the study was to study the impact and outcome of conservative management and surgical intervention in cases of postoperative discitis.

Overview of Literature

Postoperative discitis is a rare but often misdiagnosed cause of failed back syndrome. There is paucity of literature regarding management guidelines of postoperative discitis.

Methods

The study was carried out over a period of 6 years. Eighteen patients with postoperative discitis were included in the study.

Results

Conservative management with antibiotics, analgesics and bed rest were started in all the study cases. Posterior transpedicular fixation after re-exploration debridement and curettage of disc space granulation tissue was conducted in five patients in whom conservative management failed.

Conclusions

Early diagnosis and appropriate management is the key to effective treatment of postoperative discitis. Conservative management leads to excellent results in majority of cases. Surgical intervention with posterior interbody fusion and debridement is helpful when conservative treatment fails.

Successful use of tigecycline for treatment of culture-negative pyogenic vertebral osteomyelitis

BACKGROUND

Pyogenic vertebral osteomyelitis (PVO) is a severe infection that requires prolonged antimicrobial therapy and/or surgical interventions. Limited data are available on the safety and clinical efficacy of tigecycline in PVO. The objective of this study was to describe the clinical outcomes of patients treated with tigecycline for culture-negative PVO that was unresponsive to empirical antibiotic therapy including intravenous ampicillin-sulbactam plus ciprofloxacin or ampicillin-sulbactam alone.

METHODS

We retrospectively reviewed 15 patients with culture-negative PVO from 2009 through 2014. The patients received tigecycline as secondary empirical therapy, after not responding to the first empirical therapy. Clinical success was defined as recovery from symptoms and normalization of laboratory parameters at the end of therapy. Continued clinical success at 24 weeks after the end of the therapy was defined as sustained clinical success.

RESULTS

Tigecycline treatment was completed in 14 patients and discontinued in 1 due to severe nausea and vomiting. The mean age of the patients was 67.7 years (range 58-77 years), and 57.1% (8/14) were women. In all, 78.6% (11/14) of patients had risk factors for probable resistant staphylococcal and gram-negative infections such as diabetes mellitus, presence of hemodialysis catheters, and prior antibiotic usage. The average duration of tigecycline treatment was 8.3 weeks (range 6-11 weeks). Sustained clinical success was obtained in all patients.

CONCLUSIONS

Tigecycline should be considered as an alternative agent for the treatment of PVO in selected patients due to microbiological activity against resistant gram-positive and gram-negative bacteria.

Clinical characteristics and risk factors of pyogenic spondylitis caused by gram-negative bacteria

Background

There are limited data describing the clinical characteristics of pyogenic spondylitis caused by Gram-negative bacteria (GNB). The aim of this study was to investigate the predisposing factors and clinical characteristics of pyogenic spondylitis caused by GNB compared to Gram-positive cocci (GPC).

Methods

We performed a retrospective review of medical records from patients with culture-confirmed pyogenic spondylitis at four tertiary teaching hospitals over an 8-year period.

Results

A total of 344 patients with culture-confirmed pyogenic spondylitis were evaluated. There were 62 patients (18.0%) with pyogenic spondylitis caused by GNB and the most common organism was Escherichia coli (n = 35, 10.2%), followed by Pseudomonas aeruginosa (n = 10, 2.9%). Pyogenic spondylitis caused by GNB was more frequently associated with the female gender (64.5 vs. 35.5%, P <0.01), preexisting or synchronous genitourinary tract infection (32.3 vs. 2.1%, P< 0.01), and intra-abdominal infection (12.9 vs. 0.4%, P< 0.01) compared to patients with GPC. Although pyogenic spondylitis caused by GNB presented with severe sepsis more frequently (24.2 vs. 11.3%, P = 0.01), the mortality rate (6.0 vs. 5.2%) and the proportion of patients with residual disability (6.0 vs. 9.0%), defined as grade 3 or 4 (P = 0.78) 3 months after completion of treatment, were not significantly different compared to GPC patients.

Conclusion

GNB should be considered as the etiologic organism when infectious spondylitis develops in a patient with preexisting or synchronous genitourinary tract and intra-abdominal infection. In addition, the mortality rate and clinical outcomes are not significantly different between pyogenic spondylitis caused by GNB and GPC.

Microbiology and epidemiology of infectious spinal disease

Objective

Infectious spinal disease is regarded as an infection by a specific organism that affects the vertebral body, intervertebral disc and adjacent perivertebral soft tissue. Its incidence seems to be increasing as a result of larger proportion of the older patients with chronic debilitating disease, the rise of intravenous drug abuser, and the increase in spinal procedure and surgery. In Korea, studies assessing infectious spinal disease are rare and have not been addressed in recent times. The objectives of this study are to describe the epidemiology of all kind of spinal infectious disease and their clinical and microbiological characteristics as well as to assess the diagnostic methodology and the parameters related to the outcomes.

Methods

A retrospective study was performed in all infectious spinal disease cases presenting from January 2005 to April 2010 to three tertiary teaching hospitals within a city of 1.5 million in Korea. Patient demographics, risk factors, clinical features, and outcomes were assessed. Risk factors entailed the presence of diabetes, chronic renal failure, liver cirrhosis, immunosuppressants, remote infection, underlying malignancy and previous spinal surgery or procedure. We comparatively analyzed the results between the groups of pyogenic and tuberculous spinal infection. SPSS version 14 statistical software was used to perform the analyses of the data. The threshold for statistical significance was established at p<0.05.

Results

Ninety-two cases fulfilled the inclusion criteria and were reviewed. Overall, patients of tuberculous spinal infection (TSI) and pyogenic spinal infection (PSI) entailed 20 (21.7%) and 72 (78.3%) cases, respectively. A previous spinal surgery or procedure was the most commonly noted risk factor (39.1%), followed by diabetes (15.2%). The occurrence of both pyogenic and tuberculous spondylitis was predominant in the lumbar spine. Discs are more easily invaded in PSI. At initial presentation, white cell blood count and C-reactive protein levels were higher in PSI compared to TSI (p<0.05). Etiological agents were identified in 53.3%, and the most effective method for identification of etiological agents was tissue culture (50.0%). Staphyococcus aureus was the most commonly isolated infective agent associated with pyogenic spondylitis, followed by E. coli. Surgical treatment was performed in 31.5% of pyogenic spondylitis and in 35.0% of tuberculous spondylitis cases.

Conclusion

Many previous studies in Korea usually reported that tuberculous spondylitis is the predominant infection. However, in our study, the number of pyogenic infection was 3 times greater than that of tuberculous spinal disease. Etiological agents were identified in a half of all infectious spinal disease. For better outcomes, we should try to identify the causative microorganism before antibiotic therapy and make every effort to improve the result of culture and biopsy.

Rapid sensitive molecular diagnosis of pyogenic spinal infections using methicillin-resistant Staphylococcus-specific polymerase chain reaction and 16S ribosomal RNA gene-based universal polymerase chain reaction

BACKGROUND CONTEXT

Rapid diagnosis and accurate detection of etiological agents in pyogenic spinal infection (PSI) patients are important.

PURPOSE

The purpose of this study was to evaluate the clinical usefulness of methicillin-resistant Staphylococcus-specific polymerase chain reaction (MRS-PCR) and broad-range universal PCR (U-PCR) for diagnosing PSI.

STUDY DESIGN

A prospective diagnostic study.

PATIENTS

Thirty-two clinically suspect PSI patients and six control patients who underwent computerized tomography-guided biopsy and/or surgical treatment were enrolled.

METHODS

Tissue samples were examined by microbiological culture, histopathology, and real-time PCR (MRS-PCR and U-PCR). The diagnostic accuracy of real-time PCR was analyzed based on the definitive diagnosis of infection, defined as a positive result from microbiological culture or histopathology.

RESULTS

All six control subjects were negative for PSI for all analyses. Twelve clinically suspect PSI subjects received definitive diagnoses (PSI group). The non-PSI group consisted of six control subjects plus the remaining 20 patients from the PSI clinically suspect group. MRS-PCR results were positive for all MRS-cultured PSI subjects. U-PCR was positive for all subjects in the PSI group with one discrepancy between real-time PCR and microbiological culture results in differentiation between gram-positive and gram-negative bacteria. In the non-PSI group, MRS-PCR and U-PCR were positive in three and seven cases, respectively. The sensitivity, specificity, positive predictive value, and negative predictive value of MRS-PCR for diagnosing MRS infection were 1.00, 0.91, 0.57, and 1.00, respectively; those for the diagnosis of bacterial infection with U-PCR were 1.00, 0.73, 0.63, and 1.00, respectively.

CONCLUSION

Identification of MRS infection and ability to differentiate between gram-positive and gram-negative bacteria is rapidly achieved using MRS-PCR and U-PCR. Real-time PCR provides a sensitive molecular diagnosis of PSI and may contribute to antibiotic selection.

Admission inflammatory markers and isolation of a causative organism in patients with spontaneous spinal infection

INTRODUCTION

The purpose of this study was to investigate the significance of the inflammatory markers on admission in the isolation of a causative pathogen in patients with spinal infection. Spinal infection is treated frequently at spinal units and can encompass a broad range of clinical entities. Its diagnosis is often delayed because of the difficulty of identifying the responsible pathogen.

METHODS

Patients with spinal infection treated in our institution over a period of eight years were identified and their notes studied retrospectively. Admission C-reactive protein (CRP), white cell count (WCC) as well as co-morbidities and mode of pathogen identification were recorded. Overall, 96 patients were included in the study.

RESULTS

The CRP levels on admission were correlated significantly with the overall potential for isolation of a pathogen (p<0.0001) and positive biopsy cultures (p=0.0016). Admission WCC levels were associated significantly with the overall potential for isolation of a pathogen (p=0.0003) and positive biopsy cultures (p=0.0023). Both CRP and WCC levels were significantly negatively correlated with the duration of the preceding symptoms (p=0.0003 and p<0.0001 respectively). Delay in presentation was significantly negatively correlated with organism isolation (p=0.0001). Multivariate analyses identified the delay in presentation as the strongest independent variable for organism isolation (p=0.014) in cases of spontaneous spinal infection when compared with the admission CRP level (p=0.031) and WCC (p=0.056).

CONCLUSIONS

In spontaneous spinal infection, delay in presentation is the strongest independent variable for organism isolation. High inflammatory marker levels on admission are a useful prognostic marker for the overall potential of isolating a causative organism either by blood cultures or by biopsy in patients with negative blood cultures. Furthermore, the admission inflammatory marker levels allow for treating surgeons to counsel their patients of the likelihood of achieving a positive microbiological yield from biopsy.

Hematogenous pyogenic spinal infection: current perceptions

As a result of reading this article, physicians should be able to:1.Understand the importance of early diagnosis and treatment of spinal infection in an effort to avoid devastating and crippling complications such as paralysis, painful deformity, and death.2.Understand current perceptions in the ongoing debate of whether operative or conventional treatment should be preferred and in which cases.3.Understand the latest advances in the surgical treatment of spinal infection, their indications, and their effectiveness.4.Understand the change in the traditionally held belief that in the presence of infection, the use of metal implants or grafts is not indicated. Controversy exists regarding optimal treatment for pyogenic spinal infection. The authors systematically reviewed peer-reviewed published clinical trials in the English language through 2009 on the clinical presentation, complications, and conservative and operative treatments of pyogenic spinal infection. The cornerstone of therapy for uncomplicated spondylodiskitis is intravenous antibiotics followed by oral antibiotics and bracing. Surgery is effective in complicated cases and improves sagittal balance, restores neurological impairment, and relieves severe pain. In cases of delayed diagnosis or surgery, potential early devastating and late crippling complications may occur. To the authors' knowledge, no Level I studies compare operative vs conservative treatment of pyogenic spinal infection.

Brucellar spondylodiscitis: comparison of patients with and without abscesses

Brucellosis is an important cause of spondylodiscitis in endemic areas. Brucellar spondylodiscitis is a serious complication because of its association with abscess formation. Prospective studies comparing patients with and without abscesses are lacking. The objective of this study was to determine the frequency and demographic, clinical, laboratory, and radiological features of brucellar spondylodiscitis and to compare patients with and without abscesses regarding treatment and outcome. Out of 135 consecutive patients with brucellosis, 31 patients with spondylodiscitis were recruited for the study. Patients were grouped according to magnetic resonance imaging findings. The frequency of spondylodiscitis was 23.0 %. Sites of involvement were lumbar (58.1 %), lumbosacral (22.6 %), cervical (9.7 %), thoracolumbar (6.5 %), and thoracic (3.2 %). Abscesses occurred in 19 (61.3 %) patients and were associated with low hemoglobin levels. Medical treatment included a combination of streptomycin (for the first 3 weeks), doxycycline, and rifampin. The total duration of treatment was 12-39 (mean 17.0 ± 8.5 SD) weeks. By 12 weeks of treatment, evidence of clinical improvement (67 vs. 28 %) and radiological regression (92 vs. 50 %) was significantly greater in patients without abscesses. The duration of treatment was longer if an abscess was present. Two female patients with abscesses required surgical intervention. Both patients presented with high fever, neurologic deficit, and high Brucella standard tube agglutination test titers. Each patient should be evaluated individually, based on clinical findings, laboratory data, and radiological results, when undergoing treatment for brucellar spondylodiscitis. If abscesses are found, a longer course of treatment and even surgical intervention may be needed.

Bone and joint tuberculosis

INTRODUCTION

Bone and joint tuberculosis has increased in the past two decades in relation with AIDS epidemics.

MATERIAL AND METHODS

A literature review of bone and joint tuberculosis, focusing on Pott's disease.

RESULTS

Bone and joint TB comprises a group of serious infectious diseases whose incidence has increased in the past two decades, especially in underdeveloped countries, in part due to the AIDS epidemic. Tuberculous spinal infections should be suspected in patients with an insidious, progressive history of back pain and in individuals from an endemic area, especially when the thoracic vertebrae are affected and a pattern of bone destruction with relative disc preservation and paravertebral and epidural soft tissue masses are observed. Atypical tuberculous osteoarticular manifestations involving the extraspinal skeleton, a prosthetic joint, or the trochanteric area, and nontuberculous mycobacterial infections should be considered in favorable epidemiological contexts. Surgery combined with prolonged specific antituberculous chemotherapy is mainly indicated in patients with neurological manifestations or deformities, and provides satisfactory results in most cases.

CONCLUSIONS

Spinal tuberculosis is still a relative common extra spinal manifestation of spinal tuberculosis that requires a high degree of suspicion in order to avoid neurological complications and need of surgery.

Propionibacterium acnes delayed infection following spinal surgery with instrumentation

Propionibacterium acnes detection in culture media was previously considered a contamination but recently its infectious role was discovered in post-spinal surgery infections. P. acnes might be introduced during surgery. Its diagnosis is based on non-specific clinical signs, image indications of infection, and the conclusive microbiological sign. Furthermore, its diagnosis is difficult because of slow growth rate and low virulence, delaying its presentation. Usually, the infection is manifested after a couple of months or years. Here, a 65-year-old man presented with drainage at the site of instrumented spinal surgery performed 13 years ago. P. acnes infection was confirmed by culture with extended incubation. Our review of the literature revealed only two other reported cases of delayed P. acnes infection presenting a decade following a spinal surgery with instrumentation. This article sheds light on such delayed infections and discusses their presentation and management.

Postoperative spondilodiscitis

INTRODUCTION

Postoperative spondylodiscitis is a primary infection of the nucleus pulposus with secondary involvement of the cartilaginous endplate and vertebral bone. Although uncommon, postoperative spondylodiscitis causes major morbidity and may be associated with serious long-term sequelae. Several risk factors had been identified, including immunosuppression, obesity, alcohol, smoking, diabetes and malnutrition.

MATERIALS AND METHODS

A review of the literature was done to analyse the diagnosis, treatment and prevention of postoperative spondylodiscitis.

RESULTS

We found that the principles of conservative treatment are to establish an accurate microbiological diagnosis, treat with appropriate antibiotics, immobilise the spine, and closely monitor for spinal instability and neurological deterioration. The purpose of surgical treatment is to obtain multiple cultures of bone and soft tissue, perform a thorough debridement of infected tissue, decompress neural structures, and reconstruct the unstable spinal column with bone graft with or without concomitant instrumentation.

CONCLUSIONS

Appropriate management requires aggressive medical treatment and, at times, surgical intervention. If recognised early and treated appropriately, a full recovery can often be expected. Therefore, clinicians should be aware of the clinical presentation of such infections to improve patient outcome. A review of the literature was done to advance our understanding of the diagnosis, treatment, prevention and outcome of these infections.

Postoperative discitis following single-level lumbar discectomy: Our experience of 17 cases

BACKGROUND

The established protocols of treatment of postoperative lumbar discitis have not been validated till date. We report a retrospective analysis of a series of patients with discitis following single level lumbar discectomy. We analyzed the outcome of conservative treatment of postoperative discitis with the objective to define when and what surgery was required when the conservative treatment failed.

MATERIALS AND METHODS

A total of 17 cases of postoperative discitis treated from 2002 to 2009 were followed up and evaluated clinically, radiologically and by laboratory investigations. All the patients were treated initially conservatively with rest and antibiotic therapy after diagnosis and those who did not respond to conservative treatment of at least 4 weeks were treated surgically. The cases were followed up with serial C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), X-ray, computed tomography (CT) scan and magnetic resonance imaging (MRI) for at least 1 year.

RESULTS

The mean followup was 40.38 months (range 12-86 months). Four cases failed to respond to conservative therapy and were treated surgically. In three of these four cases, open debridement, transpedicular fixation and posterolateral fusion was performed, and in the fourth case percutaneous transpedicular fixation was done. In the former group, one case was diagnosed to be tubercular, in another case Staphylococcus aureus was cultured where as the third case culture was sterile. All operated patients showed evidence of interbody fusion at 1 year followup.

CONCLUSIONS

Early detection and aggressive treatment are paramount in managing postoperative discitis and the majority do well with conservative treatment. Surgical management in the form of transpedicular fixation and debridement, when required, gives excellent results.