[Infections of the spine : Pyogenic spondylodiscitis and implant-associated vertebral osteomyelitis]

[18F]FDG PET/CT Imaging Is Associated with Lower In-Hospital Mortality in Patients with Pyogenic Spondylodiscitis-A Registry-Based Analysis of 29,362 Cases

BACKGROUND

While MRI is the primary diagnostic tool for the diagnosis of spondylodiscitis, the role of [18F]-fluorodeoxyglucose ([18F]FDG) PET/CT is gaining prominence. This study aimed to determine the frequency of [18F]FDG PET/CT usage and its impact on the in-hospital mortality rate in patients with spondylodiscitis, particularly in the geriatric population.

METHODS

We conducted a Germany-wide cross-sectional study from 2019 to 2021 using an open-access, Germany-wide database, analyzing cases with ICD-10 codes M46.2-, M46.3-, and M46.4- ('Osteomyelitis of vertebrae', 'Infection of intervertebral disc (pyogenic)', and 'Discitis unspecified'). Diagnostic modalities were compared for their association with in-hospital mortality, with a focus on [18F]FDG PET/CT.

RESULTS

In total, 29,362 hospital admissions from 2019 to 2021 were analyzed. Of these, 60.1% were male and 39.9% were female, and 71.8% of the patients were aged 65 years and above. The overall in-hospital mortality rate was 6.5% for the entire cohort and 8.2% for the geriatric subgroup (p < 0.001). Contrast-enhanced (ce) MRI (48.1%) and native CT (39.4%) of the spine were the most frequently conducted diagnostic modalities. [18F]FDG PET/CT was performed in 2.7% of cases. CeCT was associated with increased in-hospital mortality (OR = 2.03, 95% CI: 1.90-2.17, p < 0.001). Cases with documented [18F]FDG PET/CT showed a lower frequency of in-hospital deaths (OR = 0.58, 95% CI: 0.18-0.50; p = 0.002). This finding was more pronounced in patients aged 65 and above (OR = 0.42, 95% CI: 0.27-0.65, p = 0.001).

CONCLUSIONS

Despite its infrequent use, [18F]FDG PET/CT was associated with a lower in-hospital mortality rate in patients with spondylodiscitis, particularly in the geriatric cohort. This study is limited by only considering data on hospitalized patients and relying on the assumption of error-free coding. Further research is needed to optimize diagnostic approaches for spondylodiscitis.

Midterm survival and risk factor analysis in patients with pyogenic vertebral osteomyelitis: a retrospective study of 155 cases

Background

Pyogenic vertebral osteomyelitis (VO) represents a clinical challenge and is linked to substantial morbidity and mortality. This study aimed to examine mortality as well as potential risk factors contributing to in-hospital mortality among patients with VO.

Methods

This retrospective analysis involved patients receiving treatment for VO at University Regensburg in Germany from January 1, 2000, to December 3, 2020. It included in-hospital mortality rate, comorbidities and pathogens. Patients were identified using ICD-10 diagnosis codes: M46.2, M46.3, M46.4, and M46.5. Kaplan-Meier probability plots and odds ratios (OR) for mortality were calculated.

Results

Out of the total cohort of 155 patients with VO, 53 patients (34.1%) died during a mean follow-up time of 87.8 ± 70.8 months. The overall mortality was 17.2% at one year, 19.9% at two years and 28.3% at five years. Patients with congestive heart failure (p = 0.005), renal disease (p < 0.001), symptoms of paraplegia (p = 0.029), and sepsis (p = 0.006) demonstrated significantly higher overall mortality rates. In 56.1% of cases, pathogens were identified, with Staphylococcus aureus (S. aureus) and other unidentified pathogens being the most common. Renal disease (OR 1.85) and congestive heart failure (OR 1.52) were identified as significant risk factors.

Conclusion

Early assessment of the specific risk factors for each patient may prove beneficial in the management and treatment of VO to reduce the risk of mortality. These findings demonstrate the importance of close monitoring of VO patients with underlying chronic organ disease and early identification and treatment of sepsis. Prioritizing identification of the exact pathogens and antibiotic sensitivity testing can improve outcomes for patients in this high-risk group.

Anterior Column Reconstruction of Destructive Vertebral Osteomyelitis at the Thoracolumbar Spine with an Expandable Vertebral Body Replacement Implant: A Retrospective, Monocentric Radiological Cohort Analysis of 24 Cases

BACKGROUND

Vertebral osteomyelitis (VO) often necessitates surgical intervention due to bone loss-induced spinal instability. Anterior column reconstruction, utilizing expandable vertebral body replacement (VBR) implants, is a recognized approach to restore stability and prevent neurological compromise. Despite various techniques, clinical evidence regarding the safety and efficacy of these implants in VO remains limited.

METHODS

A retrospective cohort analysis, spanning 2000 to 2020, was conducted on 24 destructive VO cases at a Level 1 orthopedic trauma center. Diagnosis relied on clinical, radiological, and microbiological criteria. Patient demographics, clinical presentation, surgical interventions, and radiological outcomes were assessed.

RESULTS

The study included 24 patients (62.5% male; mean age 65.6 ± 35.0 years), with 58% having healthcare-associated infections (HAVO). The mean radiological follow-up was 137.2 ± 161.7 weeks. Surgical intervention significantly improved the bi-segmental kyphotic endplate angle (BKA) postoperatively (mean -1.4° ± 13.6°). However, a noticeable loss of correction was observed over time. The study reported a mortality rate of 1/24.

CONCLUSIONS

Anterior column reconstruction using expandable VBR effectively improved local spinal alignment in destructive VO. However, the study underscores the necessity for prolonged follow-up and continuous research to refine surgical techniques and postoperative care. Addressing long-term complications and refining surgical approaches will be pivotal as the field progresses.

Value of [18F]FDG PET/CT in Diagnosis and Management of Spondylodiscitis

Vertebral osteomyelitis is the third most common form of osteomyelitis in patients over 50 years of age.Whereas prompt (pathogen-directed) therapy is crucially associated with better outcomes, the heterogeneous clinical presentation of disease with unspecific symptoms often delays adequate treatment initiation. Diagnosis requires a careful investigation of medical history, clinical findings and diagnostic imaging, including magnetic resonance imaging and nuclear medicine techniques.Due to its high sensitivity, [18F]FDG PET/CT is becoming increasingly important in diagnosis and management of spondylodiscitis, especially in the postoperative setting with presence of spinal hardware or other implantable devices in which MRI is limited.

Risk Factors for the In-Hospital Mortality in Pyogenic Vertebral Osteomyelitis: A Cross-Sectional Study on 9753 Patients

BACKGROUND

Pyogenic vertebral osteomyelitis represents a clinical challenge associated with significant morbidity and mortality. The aim of this study was to analyze potential risk factors for the in-hospital mortality of vertebral osteomyelitis (VO) patients.

METHODS

Based on the International Classification of Diseases, 10th Revision (ICD-10) codes for VO ("M46.2-", "M46.3-", and "M46.4-") data for total case numbers, secondary diagnoses, and numbers of in-hospital deaths were extracted from the Institute for the Hospital Remuneration System (InEK GmbH). Odds ratios (OR) for death were calculated for several secondary diseases and factors of interest.

RESULTS

Despite age, certain comorbidities were found to be strongly associated with increased mortality risk: Heart failure (OR = 2.80; 95% CI 2.45 to 3.20; p < 0.01), chronic kidney disease (OR = 1.83; 95% CI 1.57 to 2.13; p < 0.01), and diabetes with complications (OR = 1.86; 95% CI 1.46 to 2.38; p < 0.01). Among the complications, acute liver failure showed the highest risk for in-hospital mortality (OR = 42.41; 95% CI 23.47 to 76.62; p < 0.01). Additionally, stage III kidney failure (OR = 9.81; 95% CI 7.96 to 12.08; p < 0.01), sepsis (OR = 5.94; 95% CI 5.02 to 7.03; p < 0.01), acute respiratory failure (OR = 5.31; 95% CI 4.61 to 6.12; p < 0.01), and systemic inflammatory response syndrome (SIRS) (OR = 5.19; 95% CI 3.69 to 5.19; p < 0.01) were associated with in-hospital mortality. When analyzing the influence of pathogens, documented infection with Pseudomonas aeruginosa had the highest risk for mortality (OR = 2.74; 95% CI 2.07 to 3.63; p < 0.01), followed by Streptococci, Escherichia coli, and Staphylococcus aureus infections.

CONCLUSIONS

An early assessment of individual patient risk factors may be beneficial in the care and treatment of VO to help reduce the risks of mortality. These findings emphasize the importance of closely monitoring VO patients with chronic organ diseases, early detection and treatment of sepsis, and tailored empirical antibiotic therapy. The identification of specific pathogens and antibiotic susceptibility testing should be prioritized to improve patient outcomes in this high-risk population.

Value of [18F]FDG PET/CT in diagnosis and management of spondylodiscitis

Vertebral osteomyelitis is the third most common form of osteomyelitis in patients over 50 years of age.Whereas prompt (pathogen-directed) therapy is crucially associated with better outcomes, the heterogeneous clinical presentation of disease with unspecific symptoms often delays adequate treatment initiation. Diagnosis requires a careful investigation of medical history, clinical findings and diagnostic imaging, including magnetic resonance imaging and nuclear medicine techniques.Due to its high sensitivity, [¹⁸F]FDG PET/CT is becoming increasingly important in diagnosis and management of spondylodiscitis, especially in the postoperative setting with presence of spinal hardware or other implantable devices in which MRI is limited.

The Epidemiology of Spondylodiscitis in Germany: A Descriptive Report of Incidence Rates, Pathogens, In-Hospital Mortality, and Hospital Stays between 2010 and 2020

BACKGROUND

Spondylodiscitis can lead to significant morbidity and mortality. Understanding its up-to-date epidemiological characteristics and trends is important to improve patient care.

METHODS

This study analyzed trends in the incidence rate of spondylodiscitis cases in Germany between 2010 and 2020, as well as the pathogens, in-hospital mortality rate, and length of hospital stay. Data were obtained from the Federal Statistical Office and the Institute for the Hospital Remuneration System database. The ICD-10 codes "M46.2-", "M46.3-" and "M46.4-" were evaluated.

RESULTS

The incidence rate of spondylodiscitis increased to 14.4/100,000 inhabitants, with 59.6% cases occurring in patients 70 years or older and affecting mainly the lumbar spine (56.2%). Absolute case numbers increased from 6886 by 41.6% to 9753 in 2020 (IIR = 1.39, 95% CI 0.62-3.08). Staphylococci and Escherichia coli were the most coded pathogens. The proportion of resistant pathogens was 12.9%. In-hospital mortality rates increased to a maximum of 64.7/1000 patients in 2020, intensive care unit treatment was documented in 2697 (27.7%) cases, and the length of stay per case was 22.3 days.

CONCLUSION

The sharply increasing incidence and in-hospital mortality rate of spondylodiscitis highlights the need for patient-centered therapy to improve patient outcomes, especially in the geriatric, frail population, which is prone to infectious diseases.

Long-term patient-related quality of life outcomes and ICD-10 symptom rating (ISR) of patients with pyogenic vertebral osteomyelitis: What is the psychological impact of this life-threatening disease?

PURPOSE

We aimed to evaluate the long-term impact of the treatment of pyogenic vertebral osteomyelitis (VO) on functional outcomes and patients' quality of life (QoL) with a special focus on psychological well-being.

METHODS

A total of 156 patients with VO with a minimum clinical follow-up of 12 months were retrospectively identified and asked to participate. Patient-reported outcome measures were evaluated with the EuroQol five-dimension questionnaire (EQ-5D) and German Short-Form 36 (SF-36) outcome instruments as well as with an ICD-10 based symptom rating (ISR) and compared to normative data. Spine-specific outcomes were assessed with the Core Outcome Measure Index and the Oswestry disability index (ODI) or the Neck disability index (NDI), respectively.

RESULTS

From n = 156 eligible patients, n = 129 patients could be contacted and n = 40 returned questionnaires, yielding a response rate of 31.0%. The mean time from hospital discharge to follow-up was 83.0 ± 3.8 (13-193) months. Spine-specific outcomes showed mild to moderate disability. The mean physical health component score of the SF-36 (37.1 ± 16.7), the mean mental health component score (38.2 ± 14.0) and the mean EQ-5D VAS rating (57.1 ± 21.5) were significantly lower in comparison with the scores of an age-matched reference population (all p < 0.05). The mean total score of the ISR was 0.53 ± 0.23. On average, the cohort did not cross the threshold of clinically relevant symptom burden on any subscale.

CONCLUSION

Even almost seven years on average after completed treatment of VO, patients report impaired QoL. Assessment of psychological disorders should be implemented in clinical practice and future prospective studies.

[Infections of the spinal cord and adjacent structures]

Inflammation of the spinal cord and the adjacent structures can be caused by viruses, bacteria, fungi and parasites. Viruses predominantly infect the spinal cord and the nerve roots directly or trigger a secondary immune response, whereas bacteria, fungi and parasites tend to form abscesses, granulomas and cysts and can lead to a secondary compression of the spinal cord, similar to a destructive osteomyelitis. The etiological clarification of an acute or subacute spinal process is carried out based on the clinical presentation, the time course of the development of symptoms, the immune status, neuroimaging and microbial and/or molecular biological examinations of cerebrospinal fluid and serum. The tropism of individual pathogens to certain fiber structures and cellular clusters in the spinal cord in synopsis with the clinical presentation, neuroimaging and a history of exposure, can often quickly lead to a focused clarification and diagnosis. This article deals with important pathogens of spinal and paraspinal infections, the geographical distribution, the clinical and neuroimaging presentation with special consideration of the anatomical and topographical localization and recent epidemiological developments. Particular attention is paid to the outbreak of poliomyelitis due to circulating vaccine-derived poliovirus (cVDPV).

A Novel Construct to Treat Destructive Osteomyelitis of the Lumbar Spine in a Patient With Pre-existing Paraplegia

Treatment for vertebral osteomyelitis varies depending on the extent of pathology and includes both medical and surgical approaches. Pathogen-directed antibiotic therapy is often the first-line treatment, however, refractory cases or those with sepsis, segmental instability, or epidural abscess may be candidates for surgical treatment. Patients with extensive bony destruction often require a corpectomy with the placement of a cage for anterior column reconstruction. In this case report, we describe a patient with a complex past medical history, including paraplegia secondary to a spinal cord infarct, chronic urinary tract infections (UTIs), acute myeloid leukemia (AML), and decubitus ulcers who presented with increasing back pain and imaging demonstrating vertebral osteomyelitis and diskitis with associated epidural abscess extending from L1-L4 vertebral bodies and significant osseous destruction of the L3 and L5 vertebral bodies. A multistage surgical approach was performed involving an initial laminectomy, wound wash-out, and bony debridement followed by an additional wound wash-out and then a posterior approach for corpectomy and graft placement accomplished by tying off the thecal sac. In rare cases where patients present with complete neurologic injury and extensive destructive osteomyelitis, a posterior approach for corpectomy and stabilization may be an option.

Georg schmorl prize of the German spine society (DWG) 2021: Spinal Instability Spondylodiscitis Score (SISS)-a novel classification system for spinal instability in spontaneous spondylodiscitis

PURPOSE

Even though spinal infections are associated with high mortality and morbidity, their therapy remains challenging due to a lack of established classification systems and widely accepted guidelines for surgical treatment. This study's aim therefore was to propose a comprehensive classification system for spinal instability based on the Spinal Instability Neoplastic Score (SINS) aiding spine surgeons in choosing optimal treatment for spontaneous spondylodiscitis.

METHODS

Patients who were treated for spontaneous spondylodiscitis and received computed tomography (CT) imaging were included retrospectively. The Spinal Instability Spondylodiscitis Score (SISS) was developed by expert consensus. SINS and SISS were scored in CT-images by four readers. Intraclass correlation coefficients (ICCs) and Fleiss' Kappa were calculated to determine interrater reliabilities. Predictive validity was analyzed by cross-tabulation analysis.

RESULTS

A total of 127 patients were included, 94 (74.0%) of which were treated surgically. Mean SINS was 8.3 ± 3.2, mean SISS 8.1 ± 2.4. ICCs were 0.961 (95%-CI: 0.949-0.971) for total SINS and 0.960 (95%-CI: 0.946-0.970) for total SISS. SINS yielded false positive and negative rates of 12.5% and 67.6%, SISS of 15.2% and 40.0%, respectively.

CONCLUSION

We show high reliability and validity of the newly developed SISS in detecting unstable spinal lesions in spontaneous spondylodiscitis. Therefore, we recommend its use in evaluating treatment choices based on spinal biomechanics. It is, however, important to note that stability is merely one of multiple components in making surgical treatment decisions.

[Current practice of empiric antibiotic treatment for spondylodiscitis]

Hintergrund und Fragestellung

Bei der pyogenen Spondylodiszitis gewinnen Infektionen mit Koagulase-negativen Staphylokokken zunehmend an Bedeutung. Eine empirische Antibiose ist insbesondere bei Patienten mit schweren oder progredienten neurologischen Ausfällen sowie hämodynamischer Instabilität und im Falle von kulturnegativen Spondylodiszitiden notwendig. Ob es in Deutschland einheitliche, an das Resistenzprofil angepasste Standards der empirische Antibotikatherapie gibt, ist unklar.

Studiendesign und Untersuchungsmethoden

Es wurde an deutschen Universitäts- und berufsgenossenschaftlichen Kliniken, jeweils in den Fachbereichen Orthopädie und Unfallchirurgie, eine Umfrage zur empirischen Antibiotikatherapie bei pyogener Spondylodiszitis durchgeführt. Die Umfrageergebnisse wurden auf das Resistenzprofil der Erreger von 45 Spondylodiszitispatienten, die zwischen 2013 und 2020 in unserer Klinik behandelt wurden, angewandt. Dadurch wurden potenzielle Sensibilitäts- und Resistenzraten für die angegebenen antibiotischen Therapien errechnet.

Ergebnisse

Von den 71 angefragten Kliniken antworteten insgesamt 44 (62,0 %). Sechzehn verschiedene Antibiotikatherapien wurden als jeweiliger Standard berichtet. Darunter wurden 14 verschiedene Kombinationstherapien als Therapiestandard angegeben. Die am häufigsten angegebenen empirischen Substanzen, nämlich Amoxicillin-Clavulansäure oder Ampicillin/Sulbactam (29,5 %) und Cephalosporine (18,2 %) zeigten in Bezug auf das zuvor veröffentliche Resistenzprofil hohe potenzielle Resistenzraten von 20,0 % bzw. 35,6 %. Die höchsten potenziellen Sensibilitätsraten wurden durch die Kombinationen Vancomycin + Ampicillin/Sulbactam (91,1 % sensible Erreger), Vancomycin + Piperacillin/Tazobactam (91,1 % sensible Erreger) und Ampicillin/Sulbactam + Teicoplanin (95,6 % sensible Erreger) erreicht. Eine dieser Kombinationen wurde von drei Kliniken (6,8 %) als Standard angegeben.

Schlussfolgerung

Die deutschlandweite Umfrage zur empirischen Antibiose bei pyogener Spondylodiszitis hat eine große Heterogenität der Standardtherapien ergeben. Eine Kombination aus einem Breitspektrum-β-Laktam-Antibiotikum mit einem zusätzlichen Glykopeptidantibiotikum kann sinnvoll sein.

Thoracic spondylodiscitis secondary to Klebsiella oxytoca urosepsis-a case report

Spondylodiscitis is an insidious and infectious pathology of the spinal column attributable to pathogenic micro-organisms and occurs in a variety of contexts. These micro-organisms can be inoculated surgically or can metastasise from distant sites of infection. Klebsiella species are important community-acquired and nosocomial pathogens but are uncommonly implicated in spinal infection. Klebsiella oxytoca is more obscure than its generic relative Klebsiella pneumoniae and has only five times previously been reported in spondylodiscitis. It possesses the ability to acquire inducible and recombinant antibiotic resistance, especially in the hospital setting. We describe the case of an elderly man with complex urology and this rare sequela due to incomplete treatment of a K. oxytoca urinary infection. He developed sepsis that recurred after incomplete antibiosis and seeded to his thoracic spine causing overt spondylodiscitis. The infection fulminated and his spinal lesion deteriorated into acute spinal cord compression with neurological compromise, requiring surgical decompression, fixation and long-term antibiotics. This is a sixth documented instance of a rare spinal bacterial infection. We describe the relevant microbiology and pathology, neurosurgical considerations, and general practice points for clinicians. Our report is a novel illustration of the potentially catastrophic consequences of inadequately treated urosepsis and is a stark reminder of the importance of antimicrobial stewardship.

Is There a Difference in Clinical Features, Microbiological Epidemiology and Effective Empiric Antimicrobial Therapy Comparing Healthcare-Associated and Community-Acquired Vertebral Osteomyelitis?

Background: Empiric antibiotic therapy for suspected vertebral osteomyelitis (VO) should be initiated immediately in severely ill patients, and might be necessary for culture-negative VO. The current study aimed to identify differences between community-acquired (CA) and healthcare-associated (HA) VO in terms of clinical presentation, causative pathogens, and antibiotic susceptibility. Methods: Cases of adult patients with VO treated at a German university orthopaedic trauma center between 2000 and 2020 were retrospectively reviewed. Patient history was used to distinguish between CA and HA VO. Susceptibility of antibiotic regimens was assessed based on antibiograms of the isolated pathogens. Results: A total of 155 patients (with a male to female ratio of 1.3; and a mean age of 66.1 ± 12.4 years) with VO were identified. In 74 (47.7%) patients, infections were deemed healthcare-associated. The most frequently identified pathogens were Staphylococcus aureus (HAVO: 51.2%; CAVO: 46.8%), and Coagulase-negative Staphylococci (CoNS, HAVO: 31.7%; CAVO: 21.3%). Antibiograms of 45 patients (HAVO: n = 22; CAVO: n = 23) were evaluated. Significantly more methicillin-resistant isolates, mainly CoNS, were found in the HAVO cohort (27.3%). The highest rate of resistance was found for cefazolin (HAVO: 45.5%; CAVO: 26.1%). Significantly higher rates of resistances were seen in the HAVO cohort for mono-therapies with meropenem (36.4%), piperacillin–tazobactam (31.8%), ceftriaxone (27.3%), and co-amoxiclav (31.8%). The broadest antimicrobial coverage was achieved with either a combination of piperacillin–tazobactam + vancomycin (CAVO: 100.0%; HAVO: 90.9%) or meropenem + vancomycin (CAVO: 100.0%; HAVO: 95.5%). Conclusion: Healthcare association is common in VO. The susceptibility pattern of underlying pathogens differs from CAVO. When choosing an empiric antibiotic, combination therapy must be considered.