Spontaneous spinal infections in older people

The projected increase of vertebral osteomyelitis in Germany implies a demanding challenge for future healthcare management of aging populations

PURPOSE

Since an increase in the occurrence of native vertebral osteomyelitis (VO) is expected and reliable projections are missing, it is urgent to provide a reliable forecast model and make it a part of future health care considerations.

METHODS

Comprehensive nationwide data provided by the Federal Statistical Office of Germany were used to forecast total numbers and incidence rates (IR) of VO as a function of age and gender until 2040. Projections were done using autoregressive integrated moving average model on historical data from 2005 to 2019 in relation to official population projections from 2020 to 2040.

RESULTS

The IR of VO is expected to increase from 12.4 in 2019 to 21.5 per 100,000 inhabitants [95% CI 20.9-22.1] in 2040. The highest increase is predicted in patients over 75 years of age for both men and women leading to a steep increase in absolute numbers, which is fourfold higher compared to patients younger than 75 years. While the IR per age group will not increase any further after 2035, the subsequent increase is due to a higher number of individuals aged 75 years or older.

CONCLUSIONS

Our data suggest that increasing IR of VO will seriously challenge healthcare systems, particularly due to demographic change and increasing proportions of populations turning 75 years and older. With respect to globally fast aging populations, future health care policies need to address this burden by anticipating limitations in financial and human resources and developing high-level evidence-based guidelines for prevention and interdisciplinary treatment.

Incidence and treatment trends of infectious spondylodiscitis in South Korea: A nationwide population-based study

The incidence of infectious spondylodiscitis (IS) has increased in recent years due to an increase in the numbers of older patients with chronic diseases, as well as patients with immunocompromise, steroid use, drug abuse, invasive spinal procedures, and spinal surgeries. However, research focusing on IS in the general population is lacking. This study investigated the incidence and treatment trends of IS in South Korea using data obtained from the Health Insurance Review and Assessment Service. A total of 169,244 patients (mean age: 58.0 years) diagnosed from 2010 to 2019 were included in the study. A total of 10,991 cases were reported in 2010 and 18,533 cases in 2019. Hence, there was a 1.5-fold increase in incidence rate per 100,000 people from 22.90 in 2010 to 35.79 in 2019 (P < 0.05). The incidence rate of pyogenic spondylodiscitis per 100,000 people increased from 15.35 in 2010 to 33.75 in 2019, and that of tuberculous spondylodiscitis decreased from 7.55 in 2010 to 2.04 in 2019 (P < 0.05, respectively). Elderly individuals ≥ 60 years of age accounted for 47.6% (80,578 patients) of all cases of IS. The proportion of patients who received conservative treatment increased from 82.4% in 2010 to 85.8% in 2019, while that of patients receiving surgical treatment decreased from 17.6% to 14.2% (P < 0.05, respectively). Among surgical treatments, the proportions of corpectomy and anterior fusion declined, while proportion of incision and drainage increased (P < 0.05, respectively). The total healthcare costs increased 2.9-fold from $29,821,391.65 in 2010 to $86,815,775.81 in 2019 with a significant increase in the ratio to gross domestic product. Hence, this population-based cohort study demonstrated that the incidence rate of IS has increased in South Korea. The conservative treatment has increased, while the surgical treatment has decreased. The socioeconomic burden of IS has increased rapidly.

Spondylodiscitis in Geriatric Patients: What Are the Issues?

STUDY DESIGN

Review article.

OBJECTIVES

A review of literature on the treatment of pyogenic spondylodiscitis in geriatric patients was performed with the aim to give an overview about these special patients and a recommendation on necessary diagnostics as well as conservative and operative treatment options.

METHODS

A systematic computerized literature search was done by the spondylodiscitis working group of the German Society for Orthopedics and Trauma Surgery.

RESULTS

Spondylodiscitis has an increasing incidence by age with a peak at 75 years or older. The 1-year mortality without an appropriate treatment is with 15 to 20% extremely high. Pathogen detection is the essential diagnostic step and the basis for a sufficient antibiotic treatment. Geriatric patients have initially less elevated inflammatory parameters. Compared to younger patients. They have a longer length of hospital stay and take longer for CRP normalization. Even the outcome between conservative and operative treatment is comparable after one year. Patients with spinal instability, immobilizing pain, epidural abscess, and newly emerged neurological deficits should be considered for operative treatment.

CONCLUSIONS

The treatment of geriatric patients with pyogenic spondylodiscitis must take into account that these patients usually have multiple comorbidities. The main goals are resistance-based antibiotics and the shortest possible time of immobilization of the patient.

The Hamburg Spondylodiscitis Assessment Score (HSAS) for Immediate Evaluation of Mortality Risk on Hospital Admission

(1) Background: Patients with spondylodiscitis often present with unspecific and heterogeneous symptoms that delay diagnosis and inevitable therapeutic steps leading to increased mortality rates of up to 27%. A rapid initial triage is essential to identify patients at risk for a complicative disease course. We therefore aimed to develop a risk assessment score using fast available parameters to predict in-hospital mortality of patients admitted with spondylodiscitis. (2) Methods: A retrospective data analysis of 307 patients with spondylodiscitis recruited from 2013 to 2020 was carried out. Patients were grouped according to all-cause mortality. Via logistic regression, individual patient and clinical characteristics predictive of mortality were identified. A weighted sum score to estimate a patient's risk of mortality was developed and validated in a randomly selected subgroup of spondylodiscitis patients. (3) Results: 14% of patients with spondylodiscitis died during their in-hospital stay at a tertiary center for spinal surgery. Univariate and logistic regression analyses of parameters recorded at hospital admission showed that age older than 72.5 years, rheumatoid arthritis, creatinine > 1.29 mg/dL and CRP > 140.5 mg/L increased the risk of mortality 3.9-fold, 9.4-fold, 4.3-fold and 4.1-fold, respectively. S. aureus detection increased the risk of mortality by 2.3-fold. (4) Conclusions: The novel Hamburg Spondylodiscitis Assessment Score (HSAS) shows a good fit identifying patients at low-, moderate-, high- and very high risk for in hospital mortality on admission (AUC: 0.795; p < 0.001). The implementation of the HSAS into clinical practice could ease identification of high-risk patients using readily available parameters alone, improving the patient's safety and outcome.

The diagnostic value of cytokines for the discrimination of vertebral osteomyelitis and degenerative diseases of the spine

Vertebral osteomyelitis (VO) is a primary infection of the endplates of the vertebral bodies with secondary infection of the adjacent intervertebral discs. Diagnosis is often delayed due to unspecific symptoms and a lack of specific infection markers. In this prospective study, we determined the suitability of 27 cytokines for the discrimination of VO and degenerative diseases of the spine and compared its diagnostic potential in relation to the C-reactive protein (CRP), which is widely used as a non-specific inflammation marker in clinical diagnostics. The patients included in this study underwent surgical stabilization of the lumbar and/or thoracic spine with removal of 1 or more affected intervertebral discs, as therapy for VO (n = 16) or for erosive osteochondrosis (EO, control group, n = 20). We evaluated the cytokine and CRP concentrations before (pre-OP = -20-0d where 0 means the day of surgery) and after surgery (post-OP) on days 3-5, 6-11, 40-56, and 63-142. Compared to the control patients pre-OP, a significantly higher elevation of the 4 cytokines IL-6, IL-8, IL-12 (p70), and VEGF as well as CRP were found in the VO patients, showing an area under the curve > 0.80 pre-OP. No significant differences were observed between VO patients with high and low virulent bacteria with respect to all 5 elevated biomarkers. This is the first prospective study in which a broad spectrum of 27 cytokines was analysed via multiplex assay using sera from patients with and without VO. Our results show that, in addition to CRP, 4 different cytokines were significantly altered in VO but not control patients. The results implicate that these candidate cytokines may be used in a multiplex assay for discrimination between VO and degenerative diseases of the spine.

Clinical characteristics of pyogenic vertebral osteomyelitis, and factors associated with inadequate treatment response

OBJECTIVES

Pyogenic vertebral osteomyelitis (PVO) is associated with a high burden of disease. Our study aimed to describe characteristics at presentation of PVO, the risk of inadequate treatment response (ITR), relapse, and death, and to determine risk factors for ITR.

METHODS

Patients with an ICD-10 discharge code for PVO and admission to a major Danish university hospital between November 2016 and April 2019 were included. ITR was defined as clinical, microbiological, and/or radiological progression during treatment. Data were collected through review of medical records, and logistic regression was used to determine adjusted odds ratios (aOR).

RESULTS

Of 106 patients included, 87% presented with pain in the spine, 97% elevated CRP, 14% severe sepsis, and 13% with a history of previous spinal surgery. 39% were infected with Staphylococcus aureus and 9% with Escherichia coli. 31% responded inadequately to treatment, and risk factors for ITR were previous spinal surgery (aOR 19.29; 95% confidence interval (CI) 2.20-169.08), severe sepsis (aOR 4.59; 95% CI 1.28-15.41), and infection with Escherichia coli (aOR 8.10; 95% CI 1.71-38.45). 13% experienced relapse within the first 2 years, while the 1-year crude mortality was 12%.

CONCLUSION

Staphylococcus aureus is still the main pathogen in PVO patients, and the risks of relapse and mortality remain high. Factors found to be associated with ITR were previous spinal surgery, severe sepsis, and infection with Escherichia coli.

Vertebral Osteomyelitis After Spine Surgery: A Disease With Distinct Characteristics

STUDY DESIGN

Prospective cohort study.

OBJECTIVE

We aimed to determine the 2-year survival and to identify clinical and microbiological characteristics of patients with native vertebral osteomyelitis (VO) as compared to postoperative VO to find further strategies for improvement of the management of VO.

SUMMARY OF BACKGROUND DATA

A relevant subgroup (20%-30%) of patients with VO has a history of spine surgery. Infection in these patients might be clinically different from native VO. However, clinical, microbiological, and outcome characteristics of this disease entity have not been well studied as most trials either excluded these patients or are limited by a small cohort and short observation period.

METHODS

Between 2008 and 2013, patients who presented at a tertiary care center with symptoms and imaging findings suggestive of VO were reviewed by specialists in infectious diseases, clinical microbiology, and orthopedics to confirm the diagnosis and followed prospectively for a period of 2 years. Statistical analysis for group comparisons, survival analysis, and uni- and multivariable Cox regression models were performed.

RESULTS

Thirty percent of the patients with VO (56/189) reported a history of spine surgery in the same segment. Patients with postoperative infection had a lower ASA score (American Society of Anesthesiologists) (P = 0.01) and were less likely to suffer from comorbidities compared to native cases (P = 0.003). Infections caused by coagulase-negative staphylococci (33.3 vs. 6.5%, P < 0.001) and other bacteria of the skin flora (15.2 vs. 0%, P = 0.002) were more prevalent in postoperative patients. Suffering from native VO increased the 2-year mortality risk 3-fold, also when adjusted for the remaining risk factors ASA score and number of comorbidities (hazard ratio 2.916 [95% confidence interval 1.215 -6.999], P = 0.017).

CONCLUSION

Beside clear microbiological differences, the significant better 2-year survival supports the concept of postoperative VO presenting a distinct disease entity. The subtle disease presentation of patients with postoperative VO should not attenuate clinical suspicion of physicians.

LEVEL OF EVIDENCE

3.

Vague neck pain following a gastrointestinal procedure: a rare case presentation of vertebral osteomyelitis and cervical epidural abscess

INTRODUCTION

Vertebral osteomyelitis (VO), spondylodiscitis, and spinal epidural abscesses (SEA) are infectious and inflammatory processes impacting the spine that cause major morbidity and mortality. They require prolonged hospital stays with expensive treatment regimens. Along with acute management, studies have provided evidence highlighting poor long-term outcomes. VO accounts for ~2% of all osteomyelitis. Recent data have illustrated an increase in incidence to 5.4 per 100,000 person years. The majority of patients that present with SEA and VO typically have some combination of back pain, fevers, and neurological deficits.

CASE PRESENTATION

A 55-year-old woman with known history of hypertension and hyperlipidemia, status-post endoscopic repair of a Zenker's Diverticulum 3 weeks prior, presented to our outpatient clinic with a 2-week history of axial cervical spine pain as well as left sided scapular and deltoid pain. Further questioning and exam revealed no neurologic deficits or fever. As pain persisted and she did not respond to treatment, further imaging was performed. She was found to have cervical discitis, osteomyelitis, and a cervical epidural abscess.

DISCUSSION

Patients presenting with VO/SEA typically have spine pain with some other associated symptoms of spinal cord compression or fevers, making this a rare presentation. The urgency for discovery because of the need for emergent operative intervention is evident by the documented complications associated with a delay in diagnosis. This case report emphasizes the importance of always keeping VO/SEA on the differential for cervical spine pain even with lack of associated symptoms, in order to optimize patient care.

Outcomes and risk factors for spontaneous spondylodiscitis: Case series and meta-analysis of the literature

Despite recent improvements in surgical and antimicrobial therapies, few generally applicable guidelines exist for spondylodiscitis management. We reviewed a consecutive series of patients as well as the past 18 years of the literature and analyzed outcomes for either conservative or surgical treatment. We analyzed a consecutive series of adults with spontaneous spondylodiscitis treated at our institution over the last 6 years. We analyzed predictors for neurological deficits, vertebral collapse, and surgical treatment. We also performed a meta-analysis of the literature between 2000 and 2018, stratifying the results between surgical and conservative treatment outcomes. A younger age at diagnosis, cervical location, tubercular infection, coexistence of morbidities, and vertebral collapse were predictors of surgical intervention. Cervical spondylodiscitis, vertebral collapse, and epidural collection were associated with a higher risk of developing neurological deficits, while tubercular spondylodiscitis was associated with a higher risk of vertebral collapse. Based on the current literature, conservative treatment has success rates similar to those of surgical treatment but lower complication and mortality rates. In cases without an absolute indication for surgery, a conservative approach should be considered as the first-line treatment. A closer diagnostic and clinical follow-up should be recommended in patients with cervical tract or tubercular spondylodiscitis because of the higher risk of developing bone collapse and neurological deficits.

Could Hyperbaric Oxygen Be a Solution in the Treatment of Spinal Infections?

Background and Objective: Pyogenic spinal infections are rare and potentially devastating, requiring prompt recognition and management. Parallel to the ever-increasing number of invasive spinal procedures, its incidence is on a steady rise, particularly in an expanding elderly population. The aim of this study was to evaluate the efficacy of hyperbaric oxygen (HBO₂) therapy in the treatment of this heterogeneous group of disorders. Materials and Methods: Nineteen patients who were referred to our center for HBO₂ with a clinical diagnosis of spinal infections (vertebral osteomyelitis, pyogenic spondylitis, spondylodiscitis, surgical site infection following spine surgery, epidural abscess) were retrospectively reviewed. Results: Infection resolution was adequately achieved in 12 of 13 patients (92.3%) on magnetic resonance imaging at the end of HBO₂ treatment or during the first month of follow-up. The mean follow-up period was 11 months (range 1 month to 3 years). Conclusions: This study suggests that HBO₂ therapy is efficacious in patients with pyogenic spinal infections complicated by primary therapy failure or by medical comorbidities that may impede the eradication of microbial infection and delay wound healing. HBO₂ therapy may be useful for reducing long hospital stays, repeated surgeries, and morbidities.

Vertebral Osteomyelitis: A Comparison of Associated Outcomes in Early Versus Delayed Surgical Treatment

Background

The recommended timing of surgical intervention for vertebral osteomyelitis (VO) is controversial; however, most studies are not sufficiently powered. Our goal was to investigate the associated effects of delaying surgery in VO patients on in-hospital complications, neurologic deficits, and mortality.

Methods

Retrospective review of the National Inpatient Sample. Patients who underwent surgery for VO from 1998 to 2013 were identified using codes from the International Classification of Disease, Ninth Revision, Clinical Modification. Patients were stratified into groups based on incremental delay of surgery: 0-day delay (same-day surgery), 1-day delay, 2-day delay, 3- to 6-day delay, 7- to 14-day delay, and 14- to 30-day delay. Univariate analysis compared demographics and outcomes between groups. Multivariate logistic regression models calculated independent predictors of any complication, mortality, and neurologic deficits. A 0-day delay was the reference group.

Results

A total of 34 465 patients were identified. Delayed groups were older (same day: 53.5 vs. 7-14-day delay: 61.1) and had a higher Deyo-Charlson score (same day: 0.4901 vs. 14-30-day delay: 1.66), length of stay (same day: 4.2 vs. 14-30-day delay: 34.04 days), and total charges (same day: $63,390.78 vs. 14-30-day delay: $245,752.4), all P < .001. Delayed groups had higher surgical combined-approach rates (same day: 9.1% vs. 14-30-day delay: 31.5%) and lower anterior-approach rates (same day: 42.4% vs. 14-30-day delay: 24.2%). Delayed groups had increased mortality and complication rates. Regressions showed delayed groups as the strongest independent indicators of any complication (14-30-day delay: odds ratio [OR] 3.384), mortality (14-30-day delay: OR 10.658), and neurologic deficits (14-30-day delay: OR 3.464), all P < .001.

Conclusion

VO patients who operate within 24 hours of admission are more likely to have desirable outcomes. Patients with delayed surgery had a significantly increased risk of developing any complication, mortality, and discharging with neurologic deficits.

Level of Evidence

III.

Clinical Relevance

Medically fit patients may benefit from earlier surgical management in order to reduce risk of postoperative complications, improve outcomes, and reduce overall hospital costs.

Clinical outcomes of percutaneous suction aspiration and drainage for the treatment of infective spondylodiscitis with paravertebral or epidural abscess

BACKGROUND CONTEXT

Patients with infective spondylodiscitis who failed conservative treatment are generally indicated for open surgery. However, some patients are poor candidates for standard surgery, hence the need to evaluate less invasive approaches. Good outcomes were previously reported for percutaneous suction aspiration and drainage (PSAD) in the treatment of infective spondylodiscitis resistant to conservative therapy. We recently extended the surgical approach of PSAD to allow drainage of paravertebral or epidural abscesses in patients with progressive infective spondylodiscitis.

PURPOSE

To evaluate the clinical outcomes of PSAD for infective spondylodiscitis with paravertebral or epidural abscess.

DESIGN

Retrospective case series.

PATIENT SAMPLE

Patients with infective spondylodiscitis and associated epidural or paravertebral abscess treated using PSAD at our institution, between 1998 and 2014.

OUTCOME MEASURES

Serum levels of C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), and imaging data obtained via plain radiography, computed tomography, and magnetic resonance imaging were analyzed. Serum measurements were taken preoperatively and at several time points postoperatively. Clinical outcomes were evaluated using the modified MacNab criteria for overall functional mobility.

METHODS

Data were obtained from the patients' case notes, radiological images, and medical records. Student t test was used to assess the relevance of changes in serum levels of CRP and ESR at each evaluated time point, as well as the change in sagittal Cobb angle between the preoperative state and the state at final follow-up.

RESULTS

Fifty-two patients (31 men and 21 women; average age, 70.6 years) were included in our analysis. The median (range) CRP levels and ESR values at the time of diagnosis were 6.86 (0.04-20.15) mg/dL and 78.8 (26-120) mm/h, respectively. At 1 year postoperatively, these values had decreased to 0.18 (0.0-1.2) mg/dL and 13.8 (4-28) mm/h for CRP and ESR, respectively. At final follow-up, bone union was observed in 80.8% (42 of 52) of patients, with instability identified in five patients. Regarding functional mobility, excellent outcomes were obtained in 26.9% (14 of 52) of patients, whereas good, fair, and poor outcomes were noted in 42.3% (22 of 52), 3.9% (2 of 52), and 26.9% (14 of 52) of patients, respectively. Overall, treatment was considered effective in 69.2% (36 of 52) of patients.

CONCLUSIONS

Percutaneous suction aspiration and drainage can serve as an effective alternative to open surgery for the treatment of patients with progressive infective spondylodiscitis and associated paravertebral or epidural abscess.

Epidemiology and Outcomes of Infectious Spondylodiscitis in Hemodialysis Patients

STUDY DESIGN

A retrospective study of patients who were hospitalized for infectious spondylodiscitis over a 13-year period.

OBJECTIVE

To elucidate the epidemiology and prognostic factors of infectious spondylodiscitis in hemodialysis (HD) patients and to identify the impact of HD on infectious spondylodiscitis.

SUMMARY OF BACKGROUND DATA

Only a few case studies of infectious spondylodiscitis in HD patients can be found in the literature. Reports of prognostic factors are limited and patients' outcomes have not been well described.

METHODS

The cases of 1402 patients who were hospitalized for infectious spondylodiscitis over a 13-year period were retrospectively reviewed. Of these, 102 patients on maintenance HD were enrolled in this study. Cox proportional hazard model was used to evaluate the risk factors of mortality and recurrence.

RESULTS

The 102 enrolled patients had an average age 63.3 ± 11.2 years old and male-to-female ratio of 1:1.04. Back pain was present in 75.5% of patients and the most commonly infected site was the lumbosacral spine. Infection associated with vascular access was identified in 31.4% of patients. The prevalence of dialysis via central venous catheters was higher than prevalent HD patients. Methicillin-resistant Staphylococcus aureus was the most common pathogen, followed coagulase-negative staphylococci. The patients' in-hospital survival rate was 82.4%; their vascular access survival rate was 75.5%; their 1-year survival rate was 78.4%, and their 1-year recurrence rate was 20.2%. Congestive heart failure was associated with an increased 1-year mortality. Other variables exhibited no significant relationship with patients' in-hospital mortality, 1-year mortality or recurrence.

CONCLUSION

The characteristics and outcomes of infectious spondylodiscitis in HD patients were elucidated. Most of the demographic and clinical variables, evaluated upon admission, did not predict mortality or recurrence.

LEVEL OF EVIDENCE

3.

Epidemiology of central nervous system infectious diseases: a meta-analysis and systematic review with implications for neurosurgeons worldwide

OBJECTIVECentral nervous system (CNS) infections cause significant morbidity and mortality and often require neurosurgical intervention for proper diagnosis and treatment. However, neither the international burden of CNS infection, nor the current capacity of the neurosurgical workforce to treat these diseases is well characterized. The objective of this study was to elucidate the global incidence of surgically relevant CNS infection, highlighting geographic areas for targeted improvement in neurosurgical capacity.METHODSA systematic literature review and meta-analysis were performed to capture studies published between 1990 and 2016. PubMed, EMBASE, and Cochrane databases were searched using variations of terms relating to CNS infection and epidemiology (incidence, prevalence, burden, case fatality, etc.). To deliver a geographic breakdown of disease, results were pooled using the random-effects model and stratified by WHO region and national income status for the different CNS infection types.RESULTSThe search yielded 10,906 studies, 154 of which were used in the final qualitative analysis. A meta-analysis was performed to compute disease incidence by using data extracted from 71 of the 154 studies. The remaining 83 studies were excluded from the quantitative analysis because they did not report incidence. A total of 508,078 cases of CNS infections across all studies were included, with a total sample size of 130,681,681 individuals. Mean patient age was 35.8 years (range: newborn to 95 years), and the male/female ratio was 1:1.74. Among the 71 studies with incidence data, 39 were based in high-income countries, 25 in middle-income countries, and 7 in low-income countries. The pooled incidence of studied CNS infections was consistently highest in low-income countries, followed by middle- and then high-income countries. Regarding WHO regions, Africa had the highest pooled incidence of bacterial meningitis (65 cases/100,000 people), neurocysticercosis (650/100,000), and tuberculous spondylodiscitis (55/100,000), whereas Southeast Asia had the highest pooled incidence of intracranial abscess (49/100,000), and Europe had the highest pooled incidence of nontuberculous vertebral spondylodiscitis (5/100,000). Overall, few articles reported data on deaths associated with infection. The limited case fatality data revealed the highest case fatality for tuberculous meningitis/spondylodiscitis (21.1%) and the lowest for neurocysticercosis (5.5%). In all five disease categories, funnel plots assessing for publication bias were asymmetrical and suggested that the results may underestimate the incidence of disease.CONCLUSIONSThis systematic review and meta-analysis approximates the global incidence of neurosurgically relevant infectious diseases. These results underscore the disproportionate burden of CNS infections in the developing world, where there is a tremendous demand to provide training and resources for high-quality neurosurgical care.

Spinal infections in older people: an analysis of demographics, presenting features, microbiology and outcomes

BACKGROUND

Clinical features of infection can become more atypical as we age. Spinal infections can be insidious, and timely diagnosis and treatment are essential to prevent adverse outcomes.

AIMS

To explore differences in presentation and outcomes between younger and older patients with bacterial spinal infections.

METHODS

Clinical, microbiological and radiological information was collected for patients with spinal infections (spondylodiscitis, vertebral osteomyelitis, septic discitis, facet joint septic arthritis and spinal epidural abscess) at a single metropolitan hospital between January 2008 and January 2015. Patients were excluded if they were under 18 years of age or if clinical and imaging findings were inconsistent with the diagnosis. Presenting features, investigations and outcomes were compared for patients ≥65 (older) or <65 (younger) years old.

RESULTS

Of 53 identified patients, 34 (64%) were classified as older, with more males in both older (65%) and younger (79%) groups. Older patients presented later (median symptom duration 13 vs 4 days, P = 0.016). Back pain was nearly ubiquitous. Older patients presented less commonly with fevers (38 vs 63%) and rigors (24 vs 42%) but more commonly with hypotension (18 vs 5%), delirium (24 vs 11%), higher median inflammatory marker levels and variable microbiological findings, although these differences were not statistically significant. They had longer median lengths of stay (24 vs 14 days) and a higher likelihood of death or failure of medical treatment (HR 9.34, P = 0.031). Radicular pain was associated with poor outcome (HR 3.29, P = 0.046).

CONCLUSION

Older patients with spinal infections present later, with higher inflammatory markers and fewer typical infective symptoms and signs; these may contribute to poorer outcomes. A low threshold for promptly investigating older patients with new or worsening back pain should be set.

Low back pain in older adults: risk factors, management options and future directions

Low back pain (LBP) is one of the major disabling health conditions among older adults aged 60 years or older. While most causes of LBP among older adults are non-specific and self-limiting, seniors are prone to develop certain LBP pathologies and/or chronic LBP given their age-related physical and psychosocial changes. Unfortunately, no review has previously summarized/discussed various factors that may affect the effective LBP management among older adults. Accordingly, the objectives of the current narrative review were to comprehensively summarize common causes and risk factors (modifiable and non-modifiable) of developing severe/chronic LBP in older adults, to highlight specific issues in assessing and treating seniors with LBP, and to discuss future research directions. Existing evidence suggests that prevalence rates of severe and chronic LBP increase with older age. As compared to working-age adults, older adults are more likely to develop certain LBP pathologies (e.g., osteoporotic vertebral fractures, tumors, spinal infection, and lumbar spinal stenosis). Importantly, various age-related physical, psychological, and mental changes (e.g., spinal degeneration, comorbidities, physical inactivity, age-related changes in central pain processing, and dementia), as well as multiple risk factors (e.g., genetic, gender, and ethnicity), may affect the prognosis and management of LBP in older adults. Collectively, by understanding the impacts of various factors on the assessment and treatment of older adults with LBP, both clinicians and researchers can work toward the direction of more cost-effective and personalized LBP management for older people.

Staphylococcus aureus infections: epidemiology, pathophysiology, clinical manifestations, and management

Staphylococcus aureus is a major human pathogen that causes a wide range of clinical infections. It is a leading cause of bacteremia and infective endocarditis as well as osteoarticular, skin and soft tissue, pleuropulmonary, and device-related infections. This review comprehensively covers the epidemiology, pathophysiology, clinical manifestations, and management of each of these clinical entities. The past 2 decades have witnessed two clear shifts in the epidemiology of S. aureus infections: first, a growing number of health care-associated infections, particularly seen in infective endocarditis and prosthetic device infections, and second, an epidemic of community-associated skin and soft tissue infections driven by strains with certain virulence factors and resistance to β-lactam antibiotics. In reviewing the literature to support management strategies for these clinical manifestations, we also highlight the paucity of high-quality evidence for many key clinical questions.

Increased short- and long-term mortality among patients with infectious spondylodiscitis compared with a reference population

BACKGROUND CONTEXT

Information on short- and especially long-term mortality among patients with infectious spondylodiscitis is sparse.

PURPOSE

To analyze mortality, factors associated with death, and cause-specific mortality rates among patients with infectious nonpostoperative spondylodiscitis.

STUDY DESIGN

A case-cohort study.

PATIENT SAMPLE

We identified all patients aged 18 years or older treated for infectious spondylodiscitis from January 1994 to May 2009 at hospitals in Funen County, Denmark.

OUTCOME MEASURES

Overall and cause-specific mortality.

METHODS

Mortality rates among patients were compared with rates among a reference population using Kaplan-Meier plots and mortality rate ratios (MRRs). Short-term mortality was defined as deaths within first year after admission and long-term mortality was deaths thereafter. Factors associated with death were determined.

RESULTS

Among 298 identified patients, 61 (20%) died within the first year. Adjusted MRRs were 16.8 (95% confidence interval: 9.9-28.5) for 0 to 90 days; 4.2 (2.5-7.0) for 91 to 365 days; 2.2 (1.6-2.9) for 1 to 4 years; and 1.7 (1.2-2.5) for 5 to 14 years. Mortality rate ratios stratified on microbiological etiology were 8.8 (3.3-22.1) for 0 to 90 days; 1.4 (0.3-5.8) for 91 to 365 days; 3.2 (2.0-5.1) for 1 to 4 years; and 1.1 (0.5-2.4) for 5 to 14 years for unknown etiology and 24.0 (13.0-44.2) for 0 to 90 days; 6.0 (3.1-11.5) for 91 to 365 days; 1.9 (1.1-3.2) for 1 to 4 years; and 2.7 (1.5-4.7) for 5 to 14 years among Staphylococcus aureus infections. The main factors associated with short-term mortality were severe neurologic deficits at the time of admission, epidural abscess, and comorbidities. Long-term mortality seemed independent of microbiological etiology.

CONCLUSIONS

Mortality remained high the first year after admission and thereafter decreased with time to a level close to the reference population. Short-term mortality was especially related to infection with abscess formation and neurologic deficits and long-term mortality was related to alcohol dependency.

Trends in the epidemiology of osteomyelitis: a population-based study, 1969 to 2009

BACKGROUND

The epidemiology of osteomyelitis in the United States is largely unknown. The purpose of this study was to determine long-term secular trends in the incidence of osteomyelitis in a population-based setting.

METHODS

The study population comprised 760 incident cases of osteomyelitis first diagnosed between January 1, 1969, and December 31, 2009, among residents of Olmsted County, Minnesota. The complete medical records for each potential subject were reviewed to confirm the osteomyelitis diagnosis and to extract details on anatomical sites, infecting organisms, etiological risk factors, and outcomes.

RESULTS

The overall age and sex-adjusted annual incidence of osteomyelitis was 21.8 cases per 100,000 person-years. The annual incidence was higher for men than for women and increased with age (p < 0.001). Rates increased with the calendar year (p < 0.001) from 11.4 cases per 100,000 person-years in the period from 1969 to 1979 to 24.4 per 100,000 person-years in the period from 2000 to 2009. The incidence remained relatively stable among children and young adults but almost tripled among individuals older than sixty years; this was partly driven by a significant increase in diabetes-related osteomyelitis from 2.3 cases per 100,000 person-years in the period from 1969 to 1979 to 7.6 cases per 100,000 person-years in the period from 2000 to 2009 (p < 0.001). Forty-four percent of cases involved Staphylococcus aureus infections.

CONCLUSIONS

The reasons for the increase in osteomyelitis between 1969 and 2009 are unclear but could comprise a variety of factors, including changes in diagnosing patterns or increases in the prevalence of risk factors (e.g., diabetes) in this population.

Health care associated hematogenous pyogenic vertebral osteomyelitis: a severe and potentially preventable infectious disease

Although hematogenous pyogenic spinal infections have been related to hemodialysis (HD), catheter-related sepsis, and sporadically, to other nosocomial infections or procedures, in most recent studies and reviews the impact of nosocomial infection as a risk factor for vertebral osteomyelitis (VO) is not well established. The aim of our study was to describe the risk factors, infectious source, etiology, clinical features, therapy, and outcome of health care associated VO (HCAVO), and compare them with community-acquired VO (CAVO) cases.A retrospective cohort study of consecutive patients with hematogenous VO was conducted in our third-level hospital between 1987 and 2011. HCAVO was defined as onset of symptoms after 1 month of hospitalization or within 6 months after hospital discharge, or ambulatory manipulations in the 6 months before the diagnosis.Over the 25-year study period, among 163 hematogenous pyogenic VO, 41 (25%) were health care associated, a percentage that increased from 15% (9/61) in the 1987-1999 period to 31% (32/102) in the 2000-2011 period (P < 0.01). The presumed source of infection was an intravenous catheter in 14 (34%), cutaneous foci in 8 (20%), urinary tract in 7 (17%), gastrointestinal in 3 (7%), other foci in 3 (7%), and unknown in 6 (15%). Staphylococcus aureus was the most frequently isolated microorganism (14 cases, 34%), followed by coagulase-negative Staphylococci (CoNS) in 6 (15%), and Enterobacteriaceae in 6 (15%) cases.Compared with CAVO cases, patients with HCAVO were older (mean 66.0 SD 13.0 years vs 60.5 SD 15.5 years), had more underlying conditions (73% vs 50%, P < 0.05), neoplasm/immunosuppression (39% vs 7%, P < 0.005), chronic renal failure (19% vs 4%, P < 0.001), a known source of infection (85% vs 54% P < 0.05), Candida spp (7% vs 0%, P < 0.01) or CoNS infections (15% vs 2%, P < 0.05), higher mortality (15% vs 6%, P = 0.069), and a higher relapse rate in survivors (9% vs 1%, P < 0.05).Presently, in our setting, one-third of hematogenous pyogenic VO infections are health care associated, and a third of these are potentially preventable catheter-related infections. Compared with CAVO, in health care associated hematogenous VO, mortality and relapse rates are higher; hence, further prevention measures should be assessed.