Surgical treatment of pyogenic vertebral osteomyelitis with spinal instrumentation

Adjacent level spondylodiscitis in a patient with thoracic spondylodiscitis: A case report and review of the literature

INTRODUCTION

Adjacent level spondylodiscitis (ALS) after primary surgery for thoracic spondylodiscitis is a very rare condition.

CASE REPORT

We report the case of a 76-year-old man with this pathology. A first posterior minimally invasive approach combined with anterior approach to the thoracic spine was safely performed for thoracic spondylodiscitis. More than a year later, exploration of recurrent symptoms with ¹⁸FDG PET scan helped to diagnose ALS. Further surgery was performed. At 3-year follow-up examination showed no recurrence of the infection.

DISCUSSION

ALS should be suspected during recurrent symptoms after spinal fusion surgery. Evaluation should be based on the results of ¹⁸FDG PET scan and surgery.

CONCLUSION

Bacterial and histopathological analyses combined with an increase of spine fixation and adapted antimicrobial therapy are a safe management for ALS.

Mortality and health-related quality of life in patients surgically treated for spondylodiscitis

PURPOSE

To assess mortality, disability, and health-related quality of life (HRQL) in patients surgically treated for spondylodiscitis.

METHODS

A retrospective longitudinal study was conducted on all patients surgically treated for spondylodiscitis over a 6-year period at a single tertiary spine center. Indications for surgery, pre- and postoperative neurological impairment, comorbidities, and mortality were recorded. A survey was conducted on all eligible patients with the EuroQol 5-dimension (EQ-5D) questionnaire and Oswestry Disability Index (ODI).

RESULTS

Sixty-five patients were diagnosed with spondylodiscitis not related to recent spine surgery. One-year mortality rate was 6%. In all, 36% and 27% had pre- and postoperative neurological impairment, respectively, with only one patient experiencing deterioration postoperatively. At final follow-up (median 2 years), mean ODI was 31% (SD = 22) and mean EQ-5D time trade-off score was 0.639 (SD = 0.262); this was significantly lower than that in the normal population ( p < 0.001). Patients with neurological impairment prior to index surgery had lower EQ-5D scores ( p = 0.005) and higher ODI ( p = 0.02) at final follow-up compared with patients without neurological impairment.

CONCLUSIONS

Several years after surgery, patients surgically treated for spondylodiscitis have significantly lower HRQL and more disability than the background population. Neurological impairment prior to index surgery predicts adverse outcome in terms of disability and lower HRQL.

Fifty top-cited spine articles from mainland China: A citation analysis

Objective To identify the 50 top-cited spine articles from mainland China and to analyze their main characteristics. Methods Web of Science was used to identify the 50 top-cited spine articles from mainland China in 27 spine-related journals. The title, year of publication, number of citations, journal, anatomic focus, subspecialty, evidence level, city, institution and author were recorded. Results The top 50 articles had 29-122 citations and were published in 11 English-language journals; most (32) were published in the 2000s. The journal Spine had the largest number of articles and The Lancet had the highest impact factor. The lumber spine was the most discussed anatomic area (18). Degenerative spine disease was the most common subspecialty topic (22). Most articles were clinical studies (29); the others were basic research (21). Level IV was the most common evidence level (17). Conclusions This list indicates the most influential articles from mainland China in the global spine research community. Identification of these articles provides insights into the trends in spine care in mainland China and the historical contributions of researchers from mainland China to the international spine research field.

Man-in-the-barrel syndrome: Case report of ventral epidural abscess and review of the literature

Background:

Man-in-the-barrel syndrome (MBS) is an uncommon clinical condition for which patients present with bilateral brachial diplegia but intact lower extremity strength. This syndrome is typically attributed to a cranial/cortical injury rather than a spinal pathology.

Case Description:

A 62-year-old diabetic male presented with bilateral upper extremity paresis attributed to a ventral cervical epidural abscess diagnosed on magnetic resonance imaging. Emergent cervical decompression resulted in slight improvement of upper extremity strength. However, he later expired due to sepsis and respiratory compromise.

Conclusion:

Establishing the correct diagnosis via clinical examination and proceeding with appropriate management of MBS attributed to a cervical epidural abscess is critical to achieve a good outcome.

Release behavior of VAN from four types of CaP-ceramic granules using various loading methods at two different degrees of acidity

The release behavior of vancomycin (VAN) from beta-tricalciumphosphate (βTCP), hydroxyapatite (HA), glass ceramic (GC) and sponge-like collagen βTCP granule composite (sponge) was studied. Vacuum and drip loading methods were compared. The influence of VAN concentration and pH on release behavior was analyzed with respect to a stable release level of VAN above the minimum inhibitory concentration over 14 days. Initially the morphology of the granule carrier systems was examined with ESEM, stereomicroscopy, µCT-imaging and Camsizer® regarding porosity, interconnecting pores and granule size. Drug release patterns following a vacuum and a drip loading method with VAN at concentrations of 5 and 50 mg/ml were compared. The influence of pH 7.4 compared to pH 5.0 on release behavior was studied. The drug was released in bidistilled water at 37 °C, the concentration determined by photometry at 220 nm. For statistical purposes, the mean and standard deviation were calculated and analyzed by Origin 9.1 Professional SR1 (OriginLab). Due to low interconnectivity and low porosity, the vacuum loading method was unable to attain complete drug loading of the ceramic granules. The sponge showed an inhomogeneous distribution of βTCP granules. Drug release was high at pH 7.4, at pH 5.0 it practically did not occur. All samples except for the collagen-complex show an initial VAN burst release with a following steady release. Loading with 5 mg/ml concentrated VAN resulted in a higher percentage of available drug being released. However, when loaded with 50 mg/ml, the absolute amount of drug released was higher.

Early surgery with antibiotics treatment had better clinical outcomes than antibiotics treatment alone in patients with pyogenic spondylodiscitis: a retrospective cohort study

Background

Pyogenic spondylodiscitis is a form of spinal infection that can result in severe back pain and even death. However, information is lacking on the relative effectiveness of various therapies. A retrospective chart review was conducted to investigate whether early surgical treatment of pyogenic spondylodiscitis coupled with intravenous antibiotics results in better patient prognoses than intravenous antibiotics therapy alone.

Methods

All patients treated for pyogenic spondylodiscitis at a single medical center from July 2006 to July 2011 were retrospectively reviewed. The inclusion criteria consisted of diagnosis of an early stage infection without neurological deficit, and patients without severe sepsis who were suitable candidates for early surgery as determined by a Pittsburgh bacteremia score < 4, and patients with delayed diagnosis and lost to outpatient follow-up were excluded. Clinical outcomes included patient demographic data, kyphosis angle, length of treatment, Oswestry Disability Index and visual analogue pain scale were analyzed.

Results

Of 90 enrolled patients, Group 1 (n = 47) received only antibiotic therapy and Group 2 (n = 43) received early surgery with post-surgery antibiotics for 2 to 4 weeks. Group 2 exhibited significantly better results than Group 1 for mean antibiotic administration period, mean hospitalization period, kyphotic angle correction. Of 61 patients who participated in telephone follow-up after discharge, Group 2 (n = 26) had significant lower mean ODI score, and mean back pain score than Group 1 (n = 35).

Conclusions

While infection control was similar for both groups, patients treated with early surgery and antibiotics were hospitalized for fewer days and required less antibiotics than those treated with antibiotics alone, also having better functional outcomes. In short, early surgical treatment of pyogenic spondylodiscitis typically achieves a better prognosis, shorter hospitalization period, and subsequent significant improvement in kyphotic deformity and quality of life.

New classification for the treatment of pyogenic spondylodiscitis: validation study on a population of 250 patients with a follow-up of 2 years

PURPOSE

Pyogenic spondylodiscitis (PS) is still burdened by a high rate of orthopedic and neurological complications. Despite the rising incidence, the choice of a proper orthopedic treatment is often delayed by the lack of clinical data. The aim of this study was to propose a clinical-radiological classification of pyogenic spondylodiscitis to define a standard treatment algorithm.

METHODS

Based on data from 250 patients treated from 2008 to 2015, a clinical-radiological classification of pyogenic spondylodiscitis was developed. According to primary classification criteria (bone destruction or segmental instability, epidural abscesses and neurological impairment), three main classes were identified. Subclasses were defined according to secondary criteria. PS without segmental instability or neurological impairment was treated conservatively. When significant bone loss or neurological impairment occurred, surgical stabilization and/or decompression were performed. All patients underwent clinical and radiological 2-year follow-up.

RESULTS

Type A PS occurred in 84 patients, while 46 cases were classified as type B and 120 as type C. Average time of hospitalization was 51.94 days and overall healing rate was 92.80%. 140 patients (56.00%) were treated conservatively with average time of immobilization of 218.17 ± 9.89 days. Both VAS and SF-12 scores improved across time points in all classes. Residual chronic back pain occurred in 27 patients (10.80%). Overall observed mortality was 4.80%.

CONCLUSIONS

Standardized treatment of PS is highly recommended to ensure patients a good quality of life. The proposed scheme includes all available orthopedic treatments and helps spine surgeons to significantly reduce complications and costs and to avoid overtreatment.

Application of Intraoperative CT-Guided Navigation in Simultaneous Minimally Invasive Anterior and Posterior Surgery for Infectious Spondylitis

This study was aimed at evaluating the safety and efficacy of using intraoperative computed tomography- (iCT-) guided navigation in simultaneous minimally invasive anterior and posterior surgery for infectious spondylitis. Nine patients with infectious spondylitis were enrolled in this study. The average operative time was 327.6 min (range, 210-490) and intraoperative blood loss was 407 cc (range, 50-1,200). The average duration of hospital stay was 48.9 days (range, 11-76). Out of a total of 54 pedicle screws employed, 53 screws (98.1%) were placed accurately. A reduced visual analog scale on back pain (from 8.2 to 2.2) and Oswestry disability index (from 67.1% to 25.6%) were found at the 2-year follow-up. All patients had achieved resolution of spinal infection with reduced average erythrocyte sedimentation rate (from 83.9 to 14.1 mm/hr) and average C-reactive protein (from 54.4 to 4.8 mg/dL). Average kyphotic angle correction was 10.5° (range, 8.4°-12.6°) postoperatively and 8.5° (range, 6.9°-10.1°) after 2 years. In conclusion, the current iCT-guided navigation approach has been demonstrated to be an alternative method during simultaneous minimally invasive anterior and posterior surgery for infectious spondylitis. It can provide a good intraoperative orientation and visualization of anatomic structures and also a high pedicle screw placement accuracy in patient's lateral decubitus position.

Multidisciplinary management of spontaneous spinal infections: is there a correlation between timing, type of treatment and outcome?

BACKGROUND

Spontaneous spinal infections (SSIs) represent a rare and serious pathological entity. We tried to study a correlation between type of treatment, timing of treatment and clinical outcome through a multivariate analysis of an observational cohort study with the aim to define what is the optimal clinico-therapeutic management.

METHODS

We performed a retrospective observational cohort study on all consecutive patients observed in our Institute in a period of 13 years; from 2001 to 2014 we enrolled 50 consecutive patients with symptomatic spontaneous spinal infections (no previous surgery or recent infection in other site), confirmed with diagnostic imaging. The inclusion parameters were: diagnostic imaging, signs and symptoms positive for SSI, no history of recent infection or surgery. Of each parameter analyzed, we calculated mean and standard deviation and when necessary correlation (ρ), covariance (σ) and relation coefficient between type of treatment, timing of treatment and clinical outcome.

RESULTS

Our results suggest that an increase of one day from the onset of symptoms and the start of therapy leads to an increase in the Oswestry Disability Index Scale both at 6 months than at 1 year, with a statistical relevance, so our experience shows a statistically significant correlation and a positive co-variance between timing and outcome at 6 months and 1 year.

CONCLUSIONS

SSI are rare, very difficult to diagnose and represent a significant clinical problem. If not properly managed, they may lead to significant impact in the quality of life. The most relevant problem is not the treatment, conservative or surgical, but early diagnosis, so a careful physical, laboratory and imaging examination is fundamental, with an important help provided by isolation of the pathogen and histology. In our experience early diagnosis has a fundamental role. In the light of this, current treatment protocols may require a prompt and multidisciplinary management including infectivologists, neuroradiologists and spine surgeons.

The Safety and Decision Making of Instrumented Surgery in Infectious Spondylitis

OBJECTIVE

Infectious spondylitis is mostly managed by appropriate antibiotic treatment options, and some patients may require surgical interventions. However, surgical interventions that use spinal instrumentation to correct the mechanical instability may be associated with the risk of an increase in the recurrence rate. In this study, we investigated whether spinal instrumentation effects on recurrence of infectious spondylitis.

METHODS

The study was conducted as a retrospective study by dividing the subjects into the noninstrumentation surgery and instrumentation surgery groups among a total of 95 patients who had received surgical interventions in infectious spondylitis from 2009 to 2014. The study investigated patient variables such as underlying illness, presumed source of infection, clinical data, laboratory and radiological data, and ultimate outcome, and compared them between the 2 groups.

RESULTS

In the 95 patients, instrumentation was not used in 21 patients but it was used in 74 patients. When the disease involved ≥3 vertebral bodies, lumbosacral level and epidural part, noninstrumentation surgery was mainly conducted, but when the disease involved the thoracic level and psoas muscle part, instrumentation surgery was mainly conducted. However, there were no differences between the 2 groups in terms of the recurrence rate and the incidence of primary failure.

CONCLUSION

The use of instrumentation in treating infectious spondylitis was determined by the level of involvement and part of the infection, but the use of instrumentation did not cause any increases in the recurrence rate and the incidence of primary failure.

Vertebral Osteomyelitis Due to Granulicatella Adiacens, a Nutritionally Variant Streptococci

Vertebral osteomyelitis is a common pathology affecting the spine. We present the case of a 46-year-old male who was diagnosed with progressive L2 vertebral osteomyelitis due to a rare pathogen, Granulicatella adiacens. Granulicatella adiacens is part of the normal body flora and is often difficult to culture on traditional mediums. The patient required a lateral corpectomy and posterior fixation for spinal stabilization and source control.

SAPHO Syndrome: Imaging Findings of Vertebral Involvement

BACKGROUND AND PURPOSE

Imaging findings in patients with a combination of synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) are often misinterpreted as discitis/osteomyelitis or metastases, resulting in multiple biopsies and delayed diagnosis. We have incidentally noted a semicircular morphology in vertebral body imaging in several cases of SAPHO syndrome with vertebral involvement. Our goal was to evaluate the prevalence of this distinctive morphology in these patients.

MATERIALS AND METHODS

A retrospective review of patients with SAPHO syndrome diagnosed between July 1998 and August 2013 was conducted. A descriptive analysis of MR imaging, CT, radiography, bone scanning, and PET imaging was performed for the presence and distribution of vertebral body signal intensity or attenuation changes and/or enhancement; contiguous vertebral body involvement; vertebral body collapse; endplate irregularity; disc space, facet, and spinous process involvement; subligamentous thickening; and paraspinal soft-tissue involvement.

RESULTS

Eighteen patients (16 women [89%]; mean age, 52.9 years) with SAPHO and spine involvement were included. Contiguous involvement of ≥2 vertebral bodies was found in 16 patients (89%), with a curvilinear or "semicircular" pattern involving portions of adjacent vertebral bodies in 10 (63%, P = .14). Most intervertebral discs demonstrated absence of abnormal T2 hyperintensity (73%) and enhancement (89%). Subligamentous thickening was present in 12 (67%). Paraspinal soft-tissue involvement was present in 6 (33%).

CONCLUSIONS

SAPHO syndrome should be included in the differential diagnosis in a patient with a curvilinear or semicircular pattern of vertebral involvement, contiguous vertebral body involvement, and absence of intervertebral disc edema and enhancement.

Mycobacterial Osteomyelitis of the Spine Following Intravesical BCG Therapy for Bladder Cancer

Osteomyelitis is an infection of the bone that can involve the vertebral column. A rare cause of vertebral osteomyelitis is Mycobacterium bovis after intravesical Bacillus Calmette-Guerin (BCG) therapy for transitional cell carcinoma of the bladder. In this report, we describe the case of a 64-year-old male presenting with constitutional symptoms, progressive thoracic kyphosis, and intractable T11 and T12 radiculopathies over the proceeding six months. A CT scan revealed erosive, lytic changes of the T12 and L1 vertebrae with compression of the T12 vertebra. An MRI demonstrated T11-12 osteomyelitis with intervening discitis and extensive paraspinal enhancement with a corresponding hyperintensity on a short tau inversion recovery (STIR) sequence. A needle aspiration grew out Mycobacterial tuberculosis complex that was pansensitive to all antimicrobial agent therapies, except pyrazinamide on culture, a finding consistent with an M. bovis infection. The patient's infection and neurologic compromise resolved after transthoracic T11-12 vertebrectomies with decompression of the spinal cord and nerve roots as well as T10-L1 instrumented fusion and protracted antimicrobial therapy. The epidemiology and natural history of M. bovis osteomyelitis are reviewed and the authors emphasize a mechanism of vertebral inoculation to explain the predilection of M. bovis osteomyelitis in males after intravesical BCG therapy.

2015 Infectious Diseases Society of America (IDSA) Clinical Practice Guidelines for the Diagnosis and Treatment of Native Vertebral Osteomyelitis in Adultsa

These guidelines are intended for use by infectious disease specialists, orthopedic surgeons, neurosurgeons, radiologists, and other healthcare professionals who care for patients with native vertebral osteomyelitis (NVO). They include evidence and opinion-based recommendations for the diagnosis and management of patients with NVO treated with antimicrobial therapy, with or without surgical intervention.

When and how to operate on spondylodiscitis: a report of 13 patients

PURPOSE

Conflicting reports exist regarding the surgical indications, timing, approach, staged or not operation, and spinal instrumentation for patients with spondylodiscitis. Therefore, we performed this study to evaluate the outcome of a series of patients with spondylodiscitis aiming to answer when and how to operate on these patients.

MATERIALS AND METHODS

We retrospectively studied the files of 153 patients with spondylodiscitis treated at our institution from 2002 to 2012. The approach included MR imaging of the infected spine, isolation of the pathogen with blood cultures and/or biopsy, and further conservative or surgical treatment. The mean follow-up was 6 years (range 1-13 years). We evaluated the indications, timing (when), and methods (how) for surgical treatment, and the clinical outcome of these patients.

RESULTS

Orthopedic surgical treatment was necessary for 13 of the 153 patients (8.5 %). These were patients with low access to healthcare systems because of low socioeconomic status, third-country migrants, prisoners or intravenous drug use, patients in whom a bacterial isolate documentation was necessary, and patients with previous spinal operations. The most common pathogen was Mycobacterium tuberculosis. The surgical indications included deterioration of the neurological status (11 patients), need for bacterial isolate (10 patients), septicemia due to no response to antibiotics (five patients), and/or spinal instability (three patients). An anterior vertebral approach was more commonly used. Nine of the 13 patients had spinal instrumentation in the same setting. Improvement or recovery of the neurological status was observed postoperatively in all patients with preoperative neurological deficits. Postoperatively, two patients deceased from pulmonary infection and septicemia, and heart infarction. At the last follow-up, patients who were alive were asymptomatic; ten patients were neurologically intact, and one patient experienced paraparesis. Imaging showed spinal fusion, without evidence of recurrent spondylodiscitis. Complications related to the spinal instrumentation were not observed in the respective patients.

CONCLUSIONS

Conservative treatment is the standard for spondylodiscitis. Physicians should be alert for Mycobacterium tuberculosis spondylitis because of the low access to healthcare systems of patients with low social and economic status. Surgical indications include obtaining tissue sample for diagnosis, occurrence or progression of neurological symptoms, failure of conservative treatment, large anterior abscesses, and very extensive disease. Thorough debridement of infected tissue and spinal stability is paramount. The anterior approach provides direct access and improved exposure to the most commonly affected part of the spine. Spinal instrumentation is generally recommended for optimum spinal stability and fusion, without any implant-related complications.

Safety of instrumentation and fusion at the time of surgical debridement for spinal infection

The present study aims to assess the results of single-stage instrumentation and fusion at the time of surgical debridement of spinal infections; vertebral osteomyelitis or epidural abscess. Nine patients with spinal infection were treated with instrumentation and fusion after radical debridement in a single-stage operation. Predisposing factors and comorbidities, pain, American Spinal Injury Association motor scores, primary pathologies, microbiology and perioperative markers were recorded. Seven patients with pyogenic and two with tuberculous spinal infection were encountered; the most common pathogen was Staphylococcus aureus. Five patients were predisposed to infection because of diabetes mellitus. Duration of antibiotic therapy lasted up to 12 months. Six patients had thoracic infection, two lumbar and one cervical. No post-operative complications were encountered. There was a significant reduction in pain scores compared to pre-operatively. All patients with neurological deficits improved post-operatively. Despite introduction of hardware, no patients had a recurrence of their infection in the 12 month follow up period. Single-stage debridement and instrumentation appeared to be a safe and effective method of managing spinal infections. The combination of debridement and fusion has the dual benefit of removing a focus of infection and stabilising the spine. The current series confirms that placing titanium cages into an infected space is safe in a majority of patients. Stabilisation and correction of spinal deformity reduces pain, aids neurologic recovery and improves quality of life. The small patient population and retrospective nature limit the present study.

Risk factors for the development of deformity in patients with spinal infection

OBJECT

Bacterial spinal infections are infrequent but may lead to significant morbidity and death. Apart from neurological complications, infections may also lead to bone destruction resulting in deformity of the spine. However, the incidence of spinal deformities and risk factors is not well characterized in the literature.

METHODS

A retrospective cohort study was conducted using electronic medical records at a single institution. All patients were over 18 years of age and had a clinically and radiologically documented spinal infection that was treated surgically during the period 2006-2013. Infections were classified according to anatomical location including disc, bone, and/or epidural space. Deformities included kyphosis and/or subluxation. The authors analyzed risk factors for developing at least 1 deformity between the time of infection and operation using the Fisher exact test and chi-square test. Change in visual analog scale (VAS) scores preoperatively versus postoperatively was also analyzed using the paired t-test.

RESULTS

The study included 48 patients. The most common types of spinal infections were osteomyelitis and discitis (31%); osteomyelitis, discitis, and spinal epidural abscess (SEA; 27%); SEA only (15%); and osteomyelitis only (13%). Overall, 21 (44%) of 48 patients developed a spinal deformity. Anatomical location of infection (bone and/or disc and/or epidural space) was significantly associated with development of deformity (p < 0.001). In particular, patients with SEA had lower odds of deformity compared with patients without SEA (odds ratio 0.2, 95% confidence interval 0.05-0.9; p < 0.001). No other factor was significantly associated with deformity. Pain measured by VAS score tended to improve by a mean of 1.7 ± 2.7 points (p < 0.001) when comparing preoperative to postoperative scores.

CONCLUSIONS

In this cohort of patients, 44% developed at least 1 deformity, predominantly kyphosis. The only variable significantly associated with deformity was infection location. Patients with SEA alone demonstrated lower odds of developing a deformity compared with patients without SEA. Other analyzed variables, including age, body mass index, time from initial diagnosis to surgery, and comorbidities, were not found to be associated with development of deformity. Surgical intervention resulted in pain improvement.

Therapeutic outcomes of hematogenous vertebral osteomyelitis with instrumented surgery

BACKGROUND

Patients with hematogenous vertebral osteomyelitis (HVO) occasionally require instrumentation for spinal stabilization. However, placing instrumentation in the setting of spinal infection raises concerns about recurrent infection due to bacteria adhering to the foreign material. In this study, we evaluated the therapeutic outcomes of patients with HVO who underwent instrumented surgery.

METHODS

We conducted a retrospective chart review of adult patients with microbiologically diagnosed HVO who underwent surgical intervention in 5 tertiary care hospitals over an 8-year period.

RESULTS

A total of 153 patients with HVO underwent surgical management for their infections. Of these 153 patients, 94 (61.4%) underwent surgical debridement alone (noninstrumented surgery) and 59 (38.6%) underwent surgical debridement and instrumentation (instrumented surgery). The median durations of antibiotic therapy were 66 and 80 days for the noninstrumentation and instrumentation groups, respectively (P = .22). Clinical outcomes were similar between the groups, including rates of infection-related death (2.1% vs 0%; P = .52), primary failure (1.1% vs 5.1%; P = .30), and recurrence (4.8% vs 6.8%; P = .72). Among the instrumentation group, there was a significant decreasing trend for recurrence according to total duration of antibiotic therapy: 22.2% (4-6 weeks), 9.1% (6-8 weeks), and 2.6% (≥ 8 weeks; P = .04). Duration of pre-instrumentation antibiotic therapy and single-stage operation (vs 2-stage operation) were not risk factors for recurrence.

CONCLUSIONS

Spinal instrumentation in patients with HVO may be safe with pathogen-directed prolonged antibiotic therapy and should not be abandoned or delayed solely because of the risk of recurrence.

Case reviews of infections of the spine in patients with a history of solid organ transplantation

STUDY DESIGN

Retrospective clinical case series.

OBJECTIVE

To report on the epidemiological, microbiological, and clinical characteristics of spinal infections in patients who have undergone solid organ transplantation.

SUMMARY OF BACKGROUND DATA

Spine infections remain a therapeutic challenge, particularly in patients who are immunocompromised. Solid organ transplant patients represent a growing population of immunocompromised hosts. To our knowledge, no previous reports have examined the clinical characteristics spinal infections in this at-risk population in a systematic fashion.

METHODS

The records of patients with a history of solid organ transplantation from January 2007 through December 2012 were identified using Current Procedural Terminology procedure codes. Patients with spine infections who have received transplants were then identified using International Classification of Diseases, Ninth Revision codes for spine infection. In addition to demographic data, we recorded medical comorbidities, immunosuppressant medications, laboratory results, culture data, treatment received, and short-term results.

RESULTS

During this 6-year period, 2764 solid organ transplants were performed at our institution. Of this cohort, 6 patients (0.22%) were treated for a spinal infection. Patient's age ranged from 51 to 80 years (mean, 63 yr). All spine infections occurred within 1 year after organ transplantation. All patients had an elevated erythrocyte sedimentation rate. Only 1 patient had an elevated white blood cell count. The most common organisms were Escherichia coli and Staphylococcus. Four patients required surgical treatment. All patients had complete resolution of symptoms.

CONCLUSION

Our data suggest that patients with a history of solid organ transplantation may be more susceptible to developing spine infections than the general population. The most common organisms in our cohort were E. coli and Staphylococcus. Spine infections caused by atypical organisms do also occur in the organ transplant population, as is the case in other immunocompromised patients. The identification of these organisms and timely institution of treatment remains critical in the management of this at-risk population.

LEVEL OF EVIDENCE

4.

Epidural abscess caused by Veillonella parvula: Case report and review of the literature

Veillonella parvula, an anaerobic, Gram-negative coccus is part of the normal flora of the oral, gastrointestinal, respiratory, and genitourinary tracts in humans and animals. We herein present a case of epidural abscess caused by V. parvula in a 68-year-old man with sinus squamous cell carcinoma who presented with a 3-week history of low back pain. Blood and pus cultures were positive for Veillonella spp. After sequencing of the 16S ribosomal DNA, the pathogen was identified as V. parvula. Surgical debridement was performed following which the patient received intravenous administration of amoxicillin/clavulanate. To our knowledge, there are only seven reported cases of spinal infection caused by Veillonella spp. and these are reviewed here.

Spinal instrumentation in patients with primary spinal infections does not lead to greater recurrent infection rates: an analysis of 118 cases

OBJECTIVE

We sought to compare outcomes between patients undergoing decompression only versus decompression and instrumented fusion for primary spinal infections.

METHODS

Records of patients with a diagnosis of primary spinal infection who underwent surgical management at our institution during a 10-year period were reviewed. Patients were divided into 2 cohorts based on treatment received (decompression alone vs. decompression and instrumentation). Our primary end points were complication rates, need for reoperation, recurrent infections, and resolution of symptom(s) at last follow-up.

RESULTS

A total of 118 patients underwent surgical management for primary spinal infections. Thirty-five patients presented with a cervical spine infection, 40 with a thoracic infection, and 43 with a lumbosacral infection. The mean age at presentation was 57.1 ± 13.5 years. Thirty-six patients underwent only decompression, and 82 underwent decompression and instrumented fusion. In the decompression-only group, 8.33% of patients had continued osteomyelitis/discitis compared with 9.76% of patients in the instrumented group (P = 0.807). Importantly, the reoperation rate was also similar between the decompression-only group (19.44%) and the instrumented group (17.07%; P = 0.756). Similarly, subanalyses based on infection location revealed no significant increase in rates of recurrent infection or reoperation in patients who underwent instrumentation.

CONCLUSION

Patients who received just decompression for spinal infection had similar reoperation and continued infection rates as patients who additionally underwent instrumentation, irrespective of infection location within the spine. These findings suggest that instrumentation of the infected spine may be a safe treatment modality and should be considered when the spinal integrity is compromised.

One-stage biopsy, debridement, reconstruction, and stabilization of pyogenic vertebral osteomyelitis

Study Design Retrospective cohort study. Objective To evaluate whether the proposed one-stage biopsy, culture, debridement, and reconstruction with stabilization strategy is a viable option for pyogenic vertebral osteomyelitis (PVO). PVO is increasing in frequency globally, particularly in immunologically compromised individuals. Typically, biopsy and culture sensitivity followed by staged surgery and long-term antibiotic therapy is the mainstay of therapy. Methods This is a study of a group of 32 consecutive cases of PVO (spondylodiskitis) treated in our institution from 2010 to 2012. All cases had one-stage biopsy, culture sensitivity, debridement, reconstruction with iliac bone graft, and stabilization with titanium implants. The mean age in this series was 51 years, and the male-to-female ratio was 2.2:1. Approximately 50% of the patients had impaired immunity status. The commonest organism isolated was Pseudomonas aeruginosa. Culture-specific antibiotics were given for a minimum of 6 weeks to all patients. The follow-up period ranged from 6 months to a maximum of 2 years. All patients were assessed for wound healing, recurrence of infection, deformity progression, pain, and healing by radiologic and biochemical parameters. No generic or disease-specific outcome tools were used for this study. Results All patients had good wound healing, although there was one case of superficial infection that was resolved with debridement. There were two implant failures with pseudarthrosis and one localized kyphosis in this series. Conclusions The one-stage technique of biopsy, debridement, bone grafting, and stabilization can be recommended for most cases of PVO.

Clinical guidelines for the antimicrobial treatment of bone and joint infections in Korea

There are many various diseases in the bone and joint infections, and we tried to make antimicrobial treatment guidelines for common infectious diseases based on available data for microbiology and clinical trials. This guidelines focused on the treatment of osteomyelitis and septic arthritis, which can be experienced by physicians at diverse clinical settings. This guidelines is not applicable to diabetic foot infections, postoperative infections or post-traumatic infections which need special considerations. The guidelines for those conditions will be separately developed later. Surgical treatment of bone and joint infections, pediatric bone and joint infection, tuberculous bone and joint infection, and prophylactic antibiotic use were not included in this guideline.

Comparison of pyogenic spondylitis and tuberculous spondylitis

Pyogenic spondylitis and tuberculous spondylitis are common causes of spinal infection. It is difficult to differentiate tuberculous spondylitis and pyogenic spondylitis clinically and radiologically. Recently magnetic resonance imaging has been reported to be beneficial for early diagnosis and differential diagnosis of the spondylitis, and is being used extensively for diagnosis. However, the diagnosis must be considered in combination with corresponding changes in clinical manifestations, radiological findings, blood and tissue cultures and histopathological findings. Conservative treatments, including antimicrobial medications, are started initially. Surgical treatments, which include anterior or posterior approach, single-stage or two-stage surgery, with or without instrumentation, may be performed as indicated.

Bacteria detected after instrumentation surgery for pyogenic vertebral osteomyelitis in a canine model

OBJECTIVE

This study was designed to identify the presence, type and origin of bacteria adjacent to the metal implant in the infected region in a canine model of pyogenic vertebral osteomyelitis treated with single-stage anterior autogenous bone grafting and instrumentation.

METHODS

Dogs with pyogenic spondylodiscitis underwent one-stage debridement, autogenous bone grafting and titanium plate instrumentation and perioperative antibiotic therapy. The implants and adjacent vertebral bones were removed surgically at various postoperative time points (4, 8, 12 and 24 weeks) for bacteria detection. Bacteria were detected from retrieved spinal implants as well as surrounding bones by culture and/or pyrosequencing methods in 17 (85%) of all 20 animals. The positive rate for bacteria presence was 45% by culture and 80% by pyrosequencing method.

RESULTS

Radiological or macroscopic examination showed no signs for infection recurrence in any animal regardless of bacteria presence at the surgical site. However, organism identical with the causative bacterium for spinal infection was found in only two of nine culture-positive animals.

CONCLUSION

Within the confines of the study, the use of metallic implants in an infected area did not lead to a clinically relevant infection although bacteria may exist at the surgical site. The use of metallic implants in an infected area of the spine is safe. The metallic implants may not be the “culprit” for the persistence or recurrence of infection.

Invasive Staphylococcus aureus infections in diabetes mellitus

Staphylococcus aureus, the most virulent of the many staphylococcal species, has remained a major cause of morbidity and mortality despite the availability of numerous effective anti-staphylococcal antibiotics. S. aureus causes disease through both toxin-mediated and non-toxin-mediated mechanisms. This organism is responsible for both healthcare associated and community-based infections ranging from relatively minor skin and soft tissue infections to severe life threatening systemic infections. Patients with diabetes mellitus are at increased risk of invasive S. aureus infections. This article focuses on the spectrum of invasive S. aureus infections and discusses the clinical features, investigations and management of these infections in patients with diabetes mellitus.

Spinal infection: state of the art and management algorithm

INTRODUCTION

Spinal infection is a rare pathology although a concerning rising incidence has been observed in recent years. This increase might reflect a progressively more susceptible population but also the availability of increased diagnostic accuracy. Yet, even with improved diagnosis tools and procedures, the delay in diagnosis remains an important issue. This review aims to highlight the importance of a methodological attitude towards accurate and prompt diagnosis using an algorithm to aid on spinal infection management.

METHODS

Appropriate literature on spinal infection was selected using databases from the US National Library of Medicine and the National Institutes of Health.

RESULTS

Literature reveals that histopathological analysis of infected tissues is a paramount for diagnosis and must be performed routinely. Antibiotic therapy is transversal to both conservative and surgical approaches and must be initiated after etiological diagnosis. Indications for surgical treatment include neurological deficits or sepsis, spine instability and/or deformity, presence of epidural abscess and upon failure of conservative treatment.

CONCLUSIONS

A methodological assessment could lead to diagnosis effectiveness of spinal infection. Towards this, we present a management algorithm based on literature findings.

The management gram-negative bacterial haematogenous vertebral osteomyelitis: a case series of diagnosis, treatment and therapeutic outcomes

PURPOSE

The incidence of gram-negative bacterial haematogenous vertebral osteomyelitis (GNB HVO) is increasing. We performed a retrospective cohort study of patients with this type of infection in an effort to gain an improved understanding of the current clinical presentation, management and outcome.

METHODS

Between May 2007 and May 2010, all patients, over the age of 18 years, suffering from GNB HVO were identified and their microbiological diagnoses were evaluated.

RESULTS

This study identified seventy-nine patients with haematogenous vertebral osteomyelitis (HVO). Of these seventy-nine patients, 10 patients (12.66%) had Gram-negative organisms isolated. These organisms included Escherichia coli (4), Pseudomonas aeruginosa (3), Klebsiella pneumonia (1), Haemophilus influenza (1) and Enterobacter cloacae (1). Eight patients were successfully treated with antibiotics and/or surgery. Of the eight patients whose HVO was cured, five had Ciprofloxacin as part of their definitive antibiotic regime.

CONCLUSION

The treatment of GNB HVO is often challenging because of unpredictable resistance patterns and limited published data on effective treatment regimens. Our study has highlighted the need for prompt microbiological sampling and initiation of early appropriate antibiotic regime. The most effective treatment for GNB HVO was with oral Ciprofloxacin over a period of 6-8 weeks.

Incidence and risk factors for mortality of vertebral osteomyelitis: a retrospective analysis using the Japanese diagnosis procedure combination database

OBJECTIVE

To examine the incidence of vertebral osteomyelitis (VO) and the clinical features of VO focusing on risk factors for death using a Japanese nationwide administrative database.

DESIGN

Retrospective observational study.

SETTING

Hospitals adopting the Diagnosis Procedure Combination system during 2007-2010.

PARTICIPANTS

We identified 7118 patients who were diagnosed with VO (International Classification of Diseases, 10th Revision codes: A18.0, M46.4, M46.5, M46.8, M46.9, M48.9 and M49.3, checked with the detailed diagnoses in each case and all other codes indicating the presence of a specific infection) and hospitalised between July and December, 2007-2010, using the Japanese Diagnosis Procedure Combination database.

MAIN OUTCOME MEASURES

The annual incidence of VO was estimated. Logistic regression analysis was performed to analyse factors affecting in-hospital mortality in the VO patients. Dependent variables included patient characteristics (age, sex and comorbidities), procedures (haemodialysis and surgery) and hospital factors (type of hospital and hospital volume).

RESULTS

Overall, 58.9% of eligible patients were men and the average age was 69.2 years. The estimated incidence of VO increased from 5.3/100 000 population per year in 2007 to 7.4/100 000 population per year in 2010. In-hospital mortality was 6%. There was a linear trend between higher rates of in-hospital mortality and greater age. A higher rate of in-hospital mortality was significantly associated with haemodialysis use (ORs, 10.56 (95% CI 8.12 to 13.74)), diabetes (2.37 (1.89 to 2.98)), liver cirrhosis (2.63 (1.49 to 4.63)), malignancy (2.68, (2.10 to 3.42)) and infective endocarditis (3.19 (1.80 to 5.65)).

CONCLUSIONS

Our study demonstrates an increasing incidence of VO, and defines risk factors for death with a nationwide database. Several comorbidities were significantly associated with higher rates of in-hospital death in VO patients.

Failure modes in conservative and surgical management of infectious spondylodiscitis

PURPOSE AND METHODS

We reviewed the management, failure modes, and outcomes of 196 patients treated for infectious spondylodiscitis between January 1, 2000 and December 31, 2010, at the Spinal Unit, Aarhus University Hospital, Aarhus, Denmark. Patients with infectious spondylodiscitis at the site of previous spinal instrumentation, spinal metastases, and tuberculous and fungal spondylodiscitis were excluded.

RESULTS

Mean age at the time of treatment was 59 (range 1-89) years. The most frequently isolated microorganism was Staphylococcus aureus. The lumbosacral spine was affected in 64% of patients and the thoracic in 21%. In 24% of patients, there were neurologic compromise, four had the cauda equina syndrome and ten patients were paraplegic. Ninety-one patients were managed conservatively. Treatment failed in 12 cases, 7 patients required re-admission, 3 in-hospital deaths occurred, and 5 patients died during follow-up. Posterior debridement with pedicle screw instrumentation was performed in 75, without instrumentation in 19 cases. Seven patients underwent anterior debridement alone, and in 16 cases, anterior debridement was combined with pedicle screw instrumentation, one of which was a two-stage procedure. Re-operation took place in 12 patients during the same hospitalization and in a further 12 during follow-up. Two in-hospital deaths occurred, and five patients died during follow-up. Patients were followed for 1 year after treatment. Eight (9%) patients treated conservatively had a mild degree of back pain, and one (1%) patient presented with mild muscular weakness. Among surgically treated patients, 12 (10%) had only mild neurological impairment, one foot drop, one cauda equine dysfunction, but 4 were paraplegic. Twenty-seven (23%) complained of varying degrees of back pain.

CONCLUSIONS

Conservative measures are safe and effective for carefully selected patients without spondylodiscitic complications. Failure of conservative therapy requires surgery that can guarantee thorough debridement, decompression, restoration of spinal alignment, and correction of instability. Surgeons should master various techniques to achieve adequate debridement, and pedicle screw instrumentation may safely be used if needed.

Immediate titanium cranioplasty after debridement and craniectomy for postcraniotomy surgical site infection

BACKGROUND

For postcraniotomy surgical site infection (SSI) involving the bone, typical management involves craniectomy, debridement, and delayed cranioplasty. Disadvantages to delayed cranioplasty include cosmetic deformity, vulnerability of unprotected brain, and risks and costs associated with an additional operation. Many authors have attempted bone flap salvage by using various techniques.

OBJECTIVE

We evaluate our experience with immediate titanium mesh cranioplasty at the time of craniectomy and debridement.

METHODS

We retrospectively reviewed SSIs in patients that underwent craniotomy for treatment of a brain tumor. These patients were treated with craniectomy, debridement, and immediate titanium mesh cranioplasty followed by antibiotics. The primary outcome was recurrent infection.

RESULTS

Twelve patients met the inclusion criteria. Risk factors for infection included preoperative radiation therapy (33%), prior craniotomy (33%), and postoperative CSF leak (25%). Median follow-up was 14 months. Ten (83%) patients had long-term resolution without recurrent infection. One patient required additional surgical debridement for persistent infection with successful placement of new titanium mesh. Another patient developed recurrent infection but opted for hospice care because of tumor progression.

CONCLUSION

This series demonstrates the safety and feasibility of performing immediate titanium cranioplasty at the time of craniectomy and debridement in patients with postcraniotomy infections. This has been shown in patients with risk factors for poor wound healing. Immediate cranioplasty avoids the drawbacks, risks, and costs of delayed cranioplasty.

Epidural abscess and cauda equina syndrome after percutaneous intradiscal therapy in degenerative lumbar disc disease

BACKGROUND CONTEXT

Percutaneous intradiscal therapies are gaining popularity as a regenerative treatment option for spinal disc degeneration. The risks, benefits, and possible complications associated with such procedures have been poorly defined. As these procedures are performed with increasing frequency, the likelihood that clinicians will be faced with significant complications also increases.

PURPOSE

The purpose of this study is to describe a significant complication of a percutaneous intradiscal bone marrow and adipose tissue transplantation for symptomatic lumbar disc degeneration.

STUDY DESIGN

The study design is a case report.

METHODS

Two weeks after an injection of adipose cells, bone marrow aspirate and plasma into his L3-L4 and L5-S1 lumbar discs, a 64-year-old patient presented to the emergency room with cauda equina syndrome, fever, and back pain. Magnetic resonance imaging diagnosed L3-L4 disc extrusion, discitis with osteomyelitis, and epidural abscess, resulting in emergency decompressive surgery. An epidural abscess was drained, extruded disc material was removed, and cultures obtained. Five days later, once afebrile on antibiotics, he underwent a definitive interbody arthrodesis and stabilization.

RESULTS

Cauda equina syndrome resolved, osteomyelitis (methicillin-resistant Staphylococcus epidermidis) was treated, and instrumented arthrodesis stabilized the involved segment.

CONCLUSIONS

Complications associated with the intradiscal injection of agents, such as stem cells, fibrin glue, adipose tissue, or bone marrow, have been poorly defined. Given the nature of the degenerating disc, serious adverse events, including discitis, osteomyelitis, and extrusion of disc contents, may occur.

Posterior instrumentation, anterior column reconstruction with single posterior approach for treatment of pyogenic osteomyelitis of thoracic and lumbar spine

PURPOSE

Surgical treatment of thoracolumbar osteomyelitis consists of radical debridement, reconstruction of anterior column either with or without posterior stabilization. The objective of present study is to evaluate a case series of patients with osteomyelitis of thoracic and lumbar spine treated by single, posterior approach with posterior instrumentation and anterior column reconstruction.

METHODS

Seventeen patients underwent clinical and radiological evaluation pre and postoperatively with latest follow-up at 19 months (8-56 months) after surgery. Parameters assessed were site of infection, causative organism, angle of deformity, blood loss, duration of surgery, ICU stay, deformity correction, time to solid bony fusion, ambulatory status, neurologic status (ASIA impairment scale), and functional outcome (Kirkaldy-Willis criteria).

RESULTS

Mean operating time was 207 min and average blood loss 1,150 ml. Patients spent 2 (1-4) days in ICU and were able to walk unaided 1.6 (1-2) days after surgery. Infection receded in all 17 patients postoperatively. Solid bony fusion occurred in 15 out of 17 patients (88 %) on average 6.3 months after surgery. Functional outcome was assessed as excellent or good in 82 % of cases. Average deformity correction was 8 (1-18) degrees, with loss of correction of 4 (0-19) degrees at final follow-up.

CONCLUSIONS

Single, posterior approach addressing both columns poses safe alternative in treatment of pyogenic vertebral osteomyelitis of thoracic and lumbar spine. It proved to be less invasive resulting in faster postoperative recovery.

Minimally invasive posterior stabilization for treating spinal tuberculosis

We describe a case of dorsal-lumbar vertebral tuberculosis (Pott's disease) first treated with antibiotic therapy, bed rest, and cast. After 2 months of treatment patient's symptoms worsened. Minimally invasive posterior vertebral stabilization was carried out, with excellent clinic and radiographic results.

Spinal infections in children: a review

Spondylodiscitis affects children aged between two and eight years, and mainly involves the lumbar or lumbosacral spine. Diagnosis is difficult because the symptoms are not very specific and due to the children's difficulty in communicating. Unlike adults, children have vascularised intervertebral discs, which explains the higher incidence of this disease in this age group. C-reactive protein, and blood and urine cultures are important laboratory tests. In most cases, fine needle or traditional biopsy helps identify the pathogen particularly in patients who do not respond to the antibiotic therapy test. Magnetic resonance imaging has high sensitivity and specificity in the investigation of pyogenic infection of the spine, particularly in the early stages, when these changes are not shown in other imaging tests. X-rays can take up to six weeks to show changes. The first radiographic sign of infection is the irregularity of the vertebral endplates in the infection area, followed by their erosion and that of the adjacent bone, decreased disc space, segmental collapse, loss of lordosis (in cases of low back involvement) and ultimately, permanent structural deformity. After eight to twelve weeks, local regeneration occurs, accompanied by bone sclerosis arising from the formation of new trabecular bone, replacing the necrotic cancellous bone. Effective treatment often leads to bone fusion of the affected disc space. However, when no therapy is adopted, total vertebral collapse can occur. The treatment involves immobilisation, antibiotic therapy, and surgical decompression in more advanced cases.

Surgical treatment of spondylodiscitis. An update

CONCEPT

Spondylodiscitis refers to an infection affecting the intervertebral disk, the vertebral body or the posterior arch of the vertebra being aetiologically, pyogenic, granulomatous (tuberculosis, brucellosis, or fungal infection) or parasitic.

DIAGNOSIS

Spondylodiscitis diagnosis is based on clinical symptoms, a combination of erythrocyte sedimentation rate with C-reactive protein (CRP) tests and, less useful, leukocytosis. Blood culture is also a very cost-effective method of identifying organisms. Plain radiographs are useful, however changes may take several months to appear. Radionuclide tests are currently less used; nevertheless, fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET) shows encouraging results particularly when magnetic resonance images (MRI) are unconvincing in the distinction between degenerative changes and infection. MRI with gadolinium enhancement is the choice for image diagnosis.

MANAGEMENT

Medical management is usually the basis for treatment, alone or in combination with surgery. Surgical approach, either by endoscopy or open, is indicated for biopsy when clinical evolution is unsatisfactory and no micro-organism has been isolated, and also whenever a root, spinal cord or dural compression is seen on MRI; spinal instability or severe deformity are also clear indications for surgical treatment. Less invasive surgery either CT-scan guided or, particularly, by endoscopy has good results. However open surgery is still the standard. The anterior approach allows for anterior disc and bone debridement. The posterior approach is indicated when posterior elements are involved or in the presence of an epidural abscess. Although good results have been claimed, the use of instrumentation in the presence of an infected focus is controversial, as the use of cages or BMPs are.

Adjacent level spondylodiscitis after anterior cervical decompression and fusion

Postoperative spondylodiscitis after anterior cervical decompression and fusion (ACDF) is rare, but the same occurring at adjacent levels without disturbing the operated level is very rare. We report a case, with 5 year followup, who underwent ACDF from C5 to C7 for cervical spondylotic myelopathy. He showed neurological improvement after surgery but developed discharging sinus after 2 weeks, which healed with antibiotics. He improved on his preoperative symptoms well for the first 2 months. He started developing progressive neck pain and myelopathy after 3 months and investigations revealed spondylodiscitis at C3 and C4 with erosion, collapse, and kyphosis, without any evidence of implant failure or graft rejection at the operated level. He underwent reexploration and implant removal at the operated level (there was good fusion from C5 to C7) followed by debridement/decompression at C3, C4 along with iliac crest bone grafting and stabilization with plate and screws after maximum correction of kyphosis. The biopsy specimen grew Pseudomonas aeruginosa and appropriate sensitive antibiotics (gentamycin and ciprofloxacin) were given for 6 weeks. He was under regular followup for 5 years his myelopathy resolved completely and he is back to work. Complete decompression of the cord and fusion from C2 to C7 was demonstrable on postoperative imaging studies without any evidence of implant loosening or C1/C2 instability at the last followup.

Veillonella spondylodiscitis in a healthy 76-year-old lady

PURPOSE

To report a case of Veillonella spondylodiscitis in a healthy 76-year-old lady.

METHODS

A previously healthy 76-year-old lady presented with worsening axial back pain at the thoracolumbar junction, fever and loss of weight. Examination revealed deep tenderness over the thoracolumbar junction with painful and restricted spinal movements. The lower limb motor power, sensation and reflexes were normal.

RESULTS

Radiographs of the lumbosacral spine showed evidence of spinal instability with lateral translation and loss of disc space at L1-L2. MRI scans revealed fluid intensity within the L1-L2 disc with infective debris elevating the posterior longitudinal ligament and narrowing the spinal canal. Both tissue and blood cultures were positive for the anaerobic organism, Veillonella. A staged anterior-posterior spinal surgery followed by an extended course of antibiotics resulted in the clinical improvement and normalisation of blood parameters. A review of the literature on Veillonella infections is also presented.

CONCLUSION

The aim of this report is to bring Veillonella spondylodiscitis to the attention of spinal surgeons and infectious disease specialists and discuss the management options.

Spondylodiscitis: update on diagnosis and management

Spondylodiscitis, a term encompassing vertebral osteomyelitis, spondylitis and discitis, is the main manifestation of haematogenous osteomyelitis in patients aged over 50 years. Staphylococcus aureus is the predominant pathogen, accounting for about half of non-tuberculous cases. Diagnosis is difficult and often delayed or missed due to the rarity of the disease and the high frequency of low back pain in the general population. In this review of the published literature, we found no randomized trials on treatment and studies were too heterogeneous to allow comparison. Improvements in surgical and radiological techniques and the discovery of antimicrobial therapy have transformed the outlook for patients with this condition, but morbidity remains significant. Randomized trials are needed to assess optimal treatment duration, route of administration, and the role of combination therapy and newer agents.

Spinal Infection Multidisciplinary Management Project (SIMP): From Diagnosis to Treatment Guideline

Spine infections require a multidisciplinary approach to be treated and solved. A guide line to drive physicians in the deep complexity of such a disease is extremely helpful. SIMP suggests a flow-chart built up on clear concepts such as right and well managed antibiotic therapy, sound stability of the spine, correct and smart use of the standard and functional imaging techniques, such as f18 FDG PET/CT. In 16 months a total of 41 patients have been treated for spondylodiscitis, discitis and vertebral osteomyelitis by our team of physicians and 25 patients have been enrolled in a prospective study whose target is the assessment of the SIMP flow-chart and of every single aspect that characterize it.

Safety of instrumentation in patients with spinal infection

OBJECT

Treatment of spine infection remains a challenge for spine surgeons, with the most effective method still being a matter of debate. Most surgeons agree that in early stages of infection, antibiotic treatment should be pursued; under certain circumstances, however, surgery is recommended. The goals of surgery include radical debridement of the infective focus. In some cases, when surgery causes mechanical spinal instability, the question arises whether the risk of recurrent infection outweighs the benefits of spinal instrumentation and stabilization. The authors report their series of cases in which instrumentation was placed in actively infected sites and review the relevant literature.

METHODS

The authors performed a retrospective analysis of all cases of spinal infection that were surgically treated with debridement and placement of instrumentation at their institution between 2000 and 2006. Patient presentation, risk factor, infective organism, surgical indication, level of involvement, type of procedure, and ultimate outcome were reviewed. Improved outcome was based on improvement of initial American Spinal Injury Association Impairment Score.

RESULTS

Forty-seven patients (32 men, 15 women) were treated with instrumented surgery for spinal infection. Their average age at presentation was 54 years (range 37-78 years). Indications for placement of instrumentation included instability, pain after failure of conservative therapy, or both. Patients underwent surgery within an average of 12 days (range 1 day to 5 months) after their presentation to the authors' institution. The average length of hospital stay was 25 days (range 9-78 days). Follow-up averaged 22 months (range 1-80 months). Eight patients died; causes of death included sepsis (4 patients), cardiac arrest (2), and malignancy (2). Only 3 patients were lost to follow-up. Using American Spinal Injury Association scoring as the criterion, the patients' conditions improved in 34 cases and remained the same in 5. Complications included hematoma (2 cases), the need for hardware revision (1), and recurrent infection (2). Hardware replacement was required in 1 of the 2 patients with recurrent infection.

CONCLUSIONS

Instrumentation of the spine is safe and has an important role in stabilization of the infected spine. Despite the presence of active infection, we believe that instrumentation after radical debridement will not increase the risk of recurrent infection. In fact, greater benefit can be achieved through spinal stabilization, which can even promote accelerated healing.

Klebsiella pneumoniae-associated vertebral osteomyelitis after laparoscopic cholecystectomy

We report a case of a patient who underwent elective laparoscopic cholecystectomy and subsequently developed Klebsiella pneumoniae-associated vertebral osteomyelitis after 2 months. Development of vertebral osteomyelitis after laparoscopic cholecystectomy has never been reported previously. Diagnosis was made via magnetic resonance imaging. The patient was successfully treated with intravenous antibiotics and had a complete recovery with no neurologic sequelae.

Septic hematogenous lumbar spondylodiscitis in elderly patients with multiple risk factors: efficacy of posterior stabilization and interbody fusion with iliac crest bone graft

The conservative and operative treatment strategies of hematogenous spondylodiscitis in septic patients with multiple risk factors are controversial. The present series demonstrates the outcome of 18 elderly patients (median age, 72 years) with septic hematogenous spondylodiscitis and intraspinal abscess treated with microsurgical decompression and debridement of the infective tissue, followed by posterior stabilization and interbody fusion with iliac crest bone graft in one or two lumbar segments. The majority of the patients were unsuccessfully treated with intravenous antibiotics prior to the operation. Antibiotic therapy was continued for more than 6 weeks postoperatively. Morbidity and early mortality amounted to 50 and 17%, respectively. Three patients died in the hospital from internal complications after an initial postoperative improvement of the inflammatory clinical signs and laboratory parameters. Fifteen patients recovered from the spinal infection. Three of them died several months after discharge (cerebral hemorrhage, malignancy and unknown cause). Twelve patients had excellent or good outcomes during the follow-up period of at least 1 year. The series shows that operative decompression and eradication of the intraspinal and intervertebral infective tissue with fusion and stabilization via a posterior approach is possible in septic patients with multiple risk factors and leads to good results in those patients, who survive the initial severe stage of the septic disease. However, the morbidity and mortality suggest that this surgical treatment is not the therapy of first choice in high-risk septic patients, but may be considered in patients when conservative management has failed.

A novel canine model of acute pyogenic spondylodiscitis

New, appropriate in vivo animal models are needed for the study of the pathogenesis of spinal infections and the development of novel anti-infection strategies. The purpose of this study was to develop a canine model of acute pyogenic spondylodiscitis which can best mimic the human spinal infection process, characterized by separately inoculating bacterial suspension into the lumbar intervertebral spaces of a single animal. A total of 14 dogs were used in this study. An inoculation containing Staphylococcus aureus and sodium morrhuate was injected into the intervertebral spaces. Two pilot studies were carried out to determine the most appropriate concentration of the bacterium inoculum. Before the inoculation, the intervertebral disks were partially removed and the end plates of the adjacent two vertebrae were deliberately curetted out to make space for the inoculum and to more thoroughly expose the neighboring vertebrae to the bacterial inoculum. The dogs were euthanized at 14 days postimplantation. The bacterial loads of the infected tissues were assayed. Spondylodiscitis of the lumbar spinal column was consistently produced in 90% (nine out of ten) of the sites challenged with 10(2) colony-forming units (CFU) of S. aureus. Liver biopsy and blood culture did not show signs of systematic infections at 14 days postsurgery. Two out of four animals implanted with the suspension at a concentration higher than 10(3) CFUs were dead within 3 days postimplantation. The results indicate that this new canine model of acute pyogenic spondylodiscitis could be used to test the efficacy of different anti-infection strategies.