Clinical characteristics, treatments, and outcomes of hematogenous pyogenic vertebral osteomyelitis, 12-year experience from a tertiary hospital in central Taiwan

Droplet digital PCR aids in the diagnosis of children with fever of unknown origin --A typical case report

Many clinical conditions can cause fever of unknown origin (FUO) in children, but the etiological diagnosis remains challenging despite the variety of inspection methods available at present. This study aims to investigate the effectiveness of droplet digital polymerase chain reaction (ddPCR) in identifying pathogens in children with FUO as a novel application. A 7-month-old boy failed to obtain etiology evidence for his disease through various tests. After collecting peripheral blood for ddPCR analysis, Staphylococcus aureus and Escherichia coli were detected, and Sanger sequencing confirmed the pathogens. During the disease, the child developed septic arthritis and osteomyelitis in the femur. Despite the patient's fever being removed, his limb activity improving, and inflammatory biomarkers decreasing, avascular necrosis of the femoral head remained after targeted antibiotic treatment and surgery. If the patient had undergone ddPCR analysis at an early stage, it may be possible to avoid sequelae. ddPCR helps identify pathogens in the diagnosis of children with FUO and could be a promising complementary tool.

Risk Factors and Outcomes of Hematogenous Vertebral Osteomyelitis in Patients With Staphylococcus aureus Bacteremia

BACKGROUND

Hematogenous vertebral osteomyelitis (HVOM) is an incompletely understood complication of Staphylococcus aureus bacteremia (SAB).

METHODS

Eligible SAB patients with and without HVOM were prospectively enrolled from 1995 through 2019 at Duke University Health System. HVOM was diagnosed either radiographically or microbiologically. Multivariable logistic regression analysis was performed to identify clinical and microbial factors associated with HVOM risk. All bloodstream S. aureus isolates were genotyped using spa typing.

RESULTS

Of 3165 cases of SAB, 127 (4.0%) developed HVOM. Patients who experienced HVOM were more likely to have community-acquired SAB (30.7% vs 16.7%, P < .001), have a longer time to diagnosis of SAB (median, 5 days; interquartile range [IQR], 2-10.5 vs median, 2 days; IQR, 0-4; P < .001), and to exhibit persistent bacteremia (48.8% vs 20.6%, P < .001). A significant number of HVOM patients developed infective endocarditis (26% vs 15.2%, P = .002). Overall, 26.2% (n = 33) of SAB patients with HVOM underwent surgical intervention. Methicillin resistance (46.6% vs 41.7%, P = .318) and bacterial genotype were not associated with the development of HVOM. At the 12-month follow-up, 22% of patients with HVOM had died. Of the surviving patients, 20.4% remained on antibiotic therapy, and 29.6% had recurrence of either HVOM or SAB.

CONCLUSIONS

Among patients with SAB, HVOM risk was associated with clinical factors and not bacterial genotype. Despite being a rare complication of SAB, patients with HVOM had high all-cause mortality rates and healthcare resource requirements up to 1 year after their HVOM diagnosis. Close clinical monitoring is indicated in this vulnerable population.

Preoperative Risk Factors Affecting Outcome in Surgically Treated Pyogenic Spondylodiscitis

STUDY DESIGN

Retrospective study.

OBJECTIVE

The primary aim of this study was to investigate the predictors of severe complications in patients following surgery for pyogenic spondylodiscitis (PS) using a surgeon-maintained database. The secondary aim was to investigate the predictors of early recovery.

METHODS

We introduced a surgeon-maintained database of prospectively collected multicenter data that mainly focused on perioperative complications in 2012. Our surgeon-maintained database allows the retrospective collection of detailed data. We analyzed 143 patients who underwent surgery for PS from the 19,056 patients in the prospective surgeon-maintained database at 27 affiliated institutions between 2013 and 2017. Data relating to preoperative patient factors, infection factors, surgical factors, and pre- and postoperative blood tests was retrospectively collected. We performed multivariate regression analysis to evaluate the predictors of postoperative severe complications and early recovery in patients with PS.

RESULTS

High updated Charlson comorbidity index (uCCI), chronic pulmonary disease, diabetes, Gram-negative bacteria, pyogenic osteoarthritis, high preoperative white blood cell count, and low preoperative platelet count were significantly associated with severe complications in patients undergoing surgery for PS. A high uCCI was the sole independent negative predictor on early recovery.

CONCLUSION

Careful perioperative management is necessary if surgery is performed on patients who are at a high risk of life-threatening events.

Spinal epidural abscess as predicting factor for the necessity of early surgical intervention in patients with pyogenic spondylitis

BACKGROUND

Pyogenic spondylitis is a condition with low incidence that can lead to neurological sequelae and even life-threatening conditions. While conservative methods, including antibiotics and bracing, are considered the first-line treatment option for pyogenic spondylitis, it is important to identify patients who require early surgical intervention to prevent progressive neurologic deficits or deterioration of the systemic condition. Surgical treatment should be considered in patients with progressive neurologic deficits or deteriorating systemic condition. However, currently, there is a lack of treatment guidelines, particularly with respect to whether surgical treatment is necessary for pyogenic spondylitis. This study aims to analyze the radiological epidural abscess on MRI and clinical factors to predict the need for early surgical intervention in patients with pyogenic spondylitis and provide comprehensive insight into the necessity of early surgical intervention in these patients.

METHODS

This study retrospectively reviewed 47 patients with pyogenic spondylitis including spondylodiscitis, vertebral osteomyelitis, epidural abscess, and/or psoas abscess. All patients received plain radiographs, and a gadolinium-enhanced magnetic resonance imaging (MRI) scan. All patients have either tissue biopsies and/or blood cultures for the diagnosis of a pathogen. Demographic data, laboratory tests, and clinical predisposing factors including comorbidities and concurrent other infections were analyzed.

RESULTS

We analyzed 47 patients, 25 of whom were female, with a mean age of 70,7 years. MRI revealed that 26 of 47 patients had epidural abscesses. The surgical group had a significantly higher incidence of epidural abscess than the non-surgical group (p = 0.001). In addition, both CRP and initial body temperature (BT) were substantially higher in the surgical group compared to the non-surgical group. There was no significant difference between the surgical group and the non-surgical group in terms of age, gender, comorbidities, and concurrent infectious disorders, as well as the number of affected segments and affected spine levels. However, the surgical group had lengthier hospital stays and received more antibiotics.

CONCLUSION

The presence of an epidural abscess on MRI should be regarded crucial in the decision-making process for early surgical treatment in patients with pyogenic spondylitis in order to improve clinical outcomes.

Systemic Antimicrobial Treatment of Chronic Osteomyelitis in Adults: A Narrative Review

Chronic osteomyelitis in adults is a complex condition that requires prolonged and intensive antimicrobial therapy, but evidence on optimal selection and duration of antibiotics is limited. A review of PubMed and Ovid Embase databases was conducted to identify systematic reviews, meta-analyses, retrospective and randomised controlled trials (RCTs) on antibiotic treatment outcomes in adults with chronic osteomyelitis. Three main areas of interest were investigated: short-term versus long-term antibiotic therapy, oral versus parenteral antibiotic therapy, and combination antibiotic therapy with rifampicin versus without rifampicin. A total of 36 articles were identified and findings were synthesised using a narrative review approach. The available literature suffers from limitations, including a lack of high-quality studies, inconsistent definitions, and varying inclusion/exclusion criteria among studies. Most studies are open-labelled and lack blinding. Limited high-quality evidence exists that oral therapy is non-inferior to parenteral therapy and that shorter antibiotic duration might be appropriate in low-risk patients. Studies on the impact of rifampicin are inconclusive. Further well-designed studies are needed to provide more robust evidence in these areas.

Clinical phenotyping of spondylodiscitis and isolated spinal epidural empyema: a 20-year experience and cohort study

Background

The incidence of spondylodiscitis (SD) and isolated spinal epidural empyema (ISEE) has been increasing in the last decades, but the distinct differences between both entities are poorly understood. We aimed to evaluate the clinical phenotypes and long-term outcomes of SD and ISEE in depth.

Methods

We performed a chart review and analyzed data from our cohorts of consecutive SD and ISEE patients who were treated and assessed in detail for demographic, clinical, imaging, laboratory, and microbiologic characteristics at a university neurosurgical center in Germany from 2002 to 2021. Between-group comparisons were performed to identify meaningful differences in both entities.

Results

We included 208 patients (72 females: age 75 [75 32-90] y vs. 136 males: 65 [23-87] y, median [interquartile range], p < 0.001), of which 142 (68.3%) had SD and 66 (31.7%) had ISEE. Patients with SD were older than ISEE (ISEE: 62 y vs. SD: 70 y, p = 0.001). While SD was more common in males than females (males: n = 101, 71.1% vs. females: n = 41, 28.9%, p < 0.001), there was no sex-related difference in ISEE (males: n = 35, 53.0% vs. females: n = 31, 47.0%, p = 0.71). Obesity was more frequent in ISEE than in SD (ISEE: n = 29, 43.9% vs. SD: n = 37, 26.1%, p = 0.016). However, there were no between-group differences in rates of diabetes and immunodeficiency. In the entire study population, a causative pathogen was identified in 192 (92.3%) patients, with methicillin-susceptible staphylococcus aureus being most frequent (n = 100, 52.1%) and being more frequent in ISEE than SD (ISEE: n = 43, 65.2% vs. SD: n = 57, 40.1%, p = 0.003). SD and ISEE occurred most frequently in the lumbar spine, with no between-group differences (ISEE: n = 25, 37.9% vs. SD: n = 65, 45.8%, p = 0.297). Primary infectious sources were identified in 145 patients (69.7%) and among this skin infection was most common in both entities (ISEE: n = 14, 31.8% vs. SD: n = 25, 24.8%, p = 0.418). Furthermore, epidural administration was more frequent the primary cause of infection in ISEE than SD (ISEE: n = 12, 27.3% vs. SD: n = 5, 4.9%, p < 0.001). The most common surgical procedure in SD was instrumentation (n = 87, 61%) and in ISEE abscess evacuation (n = 63, 95%). Patients with ISEE displayed lower in-hospital complication rates compared to SD for sepsis (ISEE: n = 12, 18.2% vs. SD: n = 94, 66.2%, p < 0.001), septic embolism (ISEE: n = 4/48 cases, 8.3% vs. SD: n = 52/117 cases, 44.4%, p < 0.001), endocarditis (ISEE: n = 1/52 cases, 1.9% vs. SD: n = 23/125 cases, 18.4%, p = 0.003), relapse rate (ISEE: n = 4/46, 8.7% vs. SD: n = 27/92, 29.3%, p = 0.004), and disease-related mortality (ISEE: n = 1, 1.5% vs. SD: n = 11, 7.7%, p = 0.108). Patients with SD showed prolonged length of hospital stay (ISEE: 22 [15, 30] d vs. SD: 38 [29, 53] d, p < 0.001) and extended intensive care unit stay (ISEE: 0 [0, 4] d vs. SD: 3 [0, 12] d, p < 0.002).

Conclusions

Our 20-year experience and cohort analysis on the clinical management of SD and ISEE unveiled distinct clinical phenotypes and outcomes in both entities, with ISEE displaying a more favorable disease course with respect to complications and relapse rates as well as disease-related mortality.

2022 SPILF - Clinical Practice guidelines for the diagnosis and treatment of disco-vertebral infection in adults

These guidelines are an update of those made in 2007 at the request of the French Society of Infectious Diseases (SPILF, Société de Pathologie Infectieuse de Langue Française). They are intended for use by all healthcare professionals caring for patients with disco-vertebral infection (DVI) on spine, whether native or instrumented. They include evidence and opinion-based recommendations for the diagnosis and management of patients with DVI. ESR, PCT and scintigraphy, antibiotic therapy without microorganism identification (except for emergency situations), therapy longer than 6 weeks if the DVI is not complicated, contraindication for spinal osteosynthesis in a septic context, and prolonged dorsal decubitus are no longer to be done in DVI management. MRI study must include exploration of the entire spine with at least 2 orthogonal planes for the affected level(s). Several disco-vertebral samples must be performed if blood cultures are negative. Short, adapted treatment and directly oral antibiotherapy or early switch from intravenous to oral antibiotherapy are recommended. Consultation of a spine specialist should be requested to evaluate spinal stability. Early lifting of patients is recommended.

Image-Guided Biopsy in Acute Diskitis-Osteomyelitis: A Systematic Review and Meta-Analysis

BACKGROUND. The reported sensitivity and yield of image-guided biopsies for diskitis-osteomyelitis vary widely. OBJECTIVE. The purpose of this study was to perform a systematic review of the literature and meta-analysis of pooled sensitivity data to elucidate strategies for optimal image-guided biopsies among patients suspected to have diskitis-osteomyelitis. EVIDENCE ACQUISITION. A comprehensive literature search was performed for studies of patient populations with proven or suspected diskitis-osteomyelitis that included percutaneous image-guided biopsy as part of the workup algorithm. Type of pathogens, imaging modality used for biopsy guidance, tissue targeted, antibiotic administration at the time of biopsy, true microbiology positives, true microbiology negatives, false microbiology positives, false microbiology negatives, disease (i.e., diskitis-osteomyelitis) positives as determined by reference standard, true infection positives (i.e., positive microbiology or pathology results), and total number of biopsies performed were extracted from the studies. Microbiology sensitivity, microbiology biopsy yield, and infection sensitivity were calculated from the pooled data. These terms and the data required to calculate them were also defined in detail. EVIDENCE SYNTHESIS. Thirty-six articles satisfied inclusion criteria and were used for analysis. The pooled microbiology sensitivity, infection sensitivity, and microbiology biopsy yields were 46.6%, 70.0%, and 26.7%, respectively. Mycobacterium tuberculosis-only microbiology sensitivity was significantly higher than both pyogenic bacteria and mixed-organism microbiology sensitivity (p < .001). Staphylococcus aureus was the most common causative organism (28.6%). Pooled microbiology sensitivity was not significantly different for CT guidance and fluoroscopy guidance (p = .16). There was a statistically significant difference between pooled microbiology sensitivity of bone/end plate (45.5%) and disk/paravertebral soft-tissue (64.8%) image-guided biopsies (p < .001). There was no statistically significant difference in pooled microbiology sensitivities for patients who received antibiotics before the procedure (46.2%) and those who did not (44.6%) (p = .70). CONCLUSION. Image guidance by CT or fluoroscopy does not affect microbiology yield, disk and paravertebral soft-tissue biopsies should be considered over bone and end plate biopsies, and preprocedural antibiotic administration does not appear to impact biopsy results. CLINICAL IMPACT. Understanding and correctly applying reported statistics contribute to appropriate interpretation of the abundant literature on this topic and optimization of care for patients with diskitis-osteomyelitis.

Pyogenic spondylitis caused by Klebsiella pneumoniae: should the possibility of hypervirulent Klebsiella pneumoniae be considered?

Background

Klebsiella pneumoniae is rare but the second most common causative agent among gram-negative bacteria that cause pyogenic spondylitis. However, there are no available studies on the serotype, virulence factors, and clinical characteristics associated with K. pneumoniae-caused pyogenic spondylitis. Accordingly, we investigated the clinical characteristics of pyogenic spondylitis, K1 and K2 serotypes, and virulence factors of K. pneumoniae.

Methods

We reviewed the microbiological reports of specimens collected between January 2014 and December 2019 as well as the medical records of patients with pyogenic spondylitis caused by K. pneumoniae. We also evaluated K1 and K2 serotypes and the virulent genes rmpA, iutA, mrkD, ybtS, entB, and kfu. Strains that possessed rmpA and iutA were defined as hypervirulent K. pneumoniae.

Results

Six patients with pyogenic spondylitis caused by K. pneumoniae were enrolled in the study. The capsular serotypes K1 and K2 were present in 66.7% (4/6) of cases, and the hypervirulent strains were present in 88.3% (5/6) of cases. All patients had community-acquired infections, and all strains isolated were susceptible to antimicrobial agents. Intravenous antibiotic treatment continued for 2–7 weeks, and no patient underwent decompressive operation or surgical debridement. There was no recurrence. One patient died from pneumonia with a septic lung.

Conclusion

Hypervirulent K. pneumoniae is a rare but possible causative agent associated with pyogenic spondylitis.

Talaromyces marneffei and Burkholderia cepacia Co-Infection in a HIV-Uninfected Patient with Anti-Interferon-γ Autoantibodies

A high titer of neutralizing anti-interferon-γ autoantibodies can cause immunodeficiency associated with severe or disseminated infections caused by Talaromyces marneffei in human immunodeficiency virus-negative patients. Herein, we reported a rare case of disseminated Talaromyces marneffei and Burkholderia cepacia infection. The patient’s lungs, lymph nodes, and bronchi were involved, and he had neck abscesses and osteomyelitis. We measured the neutralizing anti-interferon-γ autoantibodies in the peripheral blood and found that the patient had a persistently high positive titer. Despite aggressive treatment, the patient developed disseminated intravascular coagulation and died. Thus, high-titer nAIGAs may be associated with multiple opportunistic, persistent and disseminated infections.

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.

The STAPH Score: A Predictor of Staphylococcus aureus as the Causative Microorganism of Native Vertebral Osteomyelitis

Background

Staphylococcus aureus (SA) is the most common causative microorganism in native vertebral osteomyelitis (NVO). Few studies have compared the clinical features of NVO due to SA (SA-NVO) and NVO due to other organisms (NSA-NVO). This study was conducted to validate a predictive score for SA-NVO to facilitate NVO treatment without broad-spectrum antimicrobial agents.

Methods

This retrospective study compared the clinical features of patients with SA-NVO and NSA-NVO who were diagnosed from 2004 to 2019. Univariate associations were assessed using χ ², Fisher's exact, or Mann-Whitney U test. Multivariable analysis was conducted using logistic regression. The optimal age cutoff point was determined by classification and regression tree analysis.

Results

Among 155 NVO patients, 98 (63.2%) had a microbiologically confirmed diagnosis: 40 (25.8%) with SA-NVO and 58 (37.4%) with NSA-NVO. Six predictors, either independently associated with SA-NVO or clinically relevant, were used to develop the STAPH prediction score: atopic dermatitis (Skin) (3 points); recent Trauma (2 points); Age < 67 years (1 point); Abscess (1 point); central venous Port catheter (2 points); and History of puncture (2 points). In a receiver operating characteristic analysis, the area under the curve was 0.84 (95% confidence interval, 0.76-0.91). The best cutoff point was 3. A score ≥3 had a sensitivity, specificity, positive predictive value, and negative predictive value of 58%, 84%, 84%, and 73%, respectively.

Conclusions

The STAPH score has relatively high specificity for use by clinicians to predict SA as the causative microorganism in patients with NVO until results of a confirmatory culture are available.

Surgical Management of Thoracic Osteomyelitis due to Escherichia Coli Sepsis

Case Report. Escherichia coli is a rare cause of vertebral osteomyelitis. It is more common in adults and males. We present a case of an immunocompetent adult male presenting with a several month history of progressive systemic symptoms and subsequent neurologic compromise. We discuss the neurosurgical evaluation of a patient with a progressive vertebral osteomyelitis and treatment options. Surgical debridement and spinal stabilization were performed and confirmed the diagnosis. The patient successfully completed a prolonged antimicrobial therapy course. The patient made a complete neurologic recovery. We discuss the presentation of a patient with Escherichia coli vertebral osteomyelitis and the successful surgical management.

Roseomonas species infections in humans: a systematic review

Roseomonas species have been recognized to cause infections in immunocompromised individuals. The purpose of this study was to systemically review all published cases of Roseomonas infections in humans and describe the epidemiology, microbiology, antimicrobial susceptibility, treatment and outcomes of these infections in humans. We performed a systematic review of PubMed (through 20th Octrober 2019) for studies providing epidemiological, clinical, microbiological as well as treatment data and outcomes of Roseomonas species infections. A total of 37 studies, containing data of 99 patients, were included in the analysis. The most common Roseomonas infections were those of the bloodstream in 74.7% (74 patients), musculoskeletal infections in 8.1% (8 patients), skin and soft tissue infections (SSTIs) and peritoneal dialysis-associated peritonitis in 6.1% (6 patients) each. Epidemiology of these infections differed, with bacteremias being more prevalent in patients with malignancy and central venous lines, musculoskeletal infections being more prevalent after orthopedic surgery, and SSTIs occurring without any reported underlying cause. Resistance to beta-lactams was very high with penicillin, piperacillin/tazobactam resistance and cephalosporin resistance at 96.6%, 90.7% and 77.8% respectively, while quinolone resistance was 9.1%. Quinolones, carbapenems and cephalosporins are the most common agents used for treatment, irrespectively of the infection site. Overall mortality was 3% (3 patients), with the mortality attributed to Roseomonas being at 1% (1 patient).

Linezolid as salvage therapy for central nervous system infections due to methicillin-resistant Staphylococcus aureus at two medical centers in Taiwan

BACKGROUND

Methicillin-resistant Staphylococcus aureus (MRSA)-associated central nervous system infections are potentially devastating. Linezolid has good penetration into cerebrospinal fluid and brain tissue. In clinical practice, linezolid may be used to treat central nervous system infections caused by MRSA resulting from glycopeptide intolerance or treatment failure. However, the clinical experience of linezolid in treating MRSA related central nervous system infections is scarce.

METHODS

From 2006 to 2016, patients aged ≥20 years who had central nervous system infections caused by MRSA treated with linezolid for more than 24 hours were retrospectively included from two medical centers. The demographic details, treatment response, side effects, and relapse of infection were reviewed.

RESULTS

Sixty-six patients with proven CNS infection caused by MRSA were treated with linezolid. The mean age was 53.3 years. The diagnoses in this cohort consisted of brain abscesses (n = 19, 28.8%), spinal epidural abscess (n = 18, 27.3%), meningitis only (n = 12, 18.2%), meningitis with brain epidural abscess (n = 9, 13.6%), and spine device-related infection (n = 5, 7.6%). The main reasons to prescribe linezolid were glycopeptide treatment failure (51.5%) and glycopeptide allergy (48.5%). Ninety-one percent of patients were treated with linezolid for more than 14 days. The in-hospital mortality rate was 13.6%. The relapse rate after treatment was 16.7%. Drug-related adverse events (mainly cytopenia) were observed in 27.3% of patients, but none of the adverse events was fatal.

CONCLUSIONS

In our retrospective study, linezolid demonstrated promising effect as a salvage therapy for central nervous system infection caused by MRSA, whether due to drug allergy or glycopeptide treatment failure.

Vertebral osteomyelitis: Clinical, microbiological and radiological characteristics of 116 patients

INTRODUCTION/OBJECTIVES

To describe the clinical, radiological and microbiological characteristics of vertebral osteomyelitis patients, analysing the factors that played a role on their outcome.

PATIENTS AND METHODS

Single-centre retrospective observational study including patients diagnosed with vertebral osteomyelitis, based on the combination of clinical presentation with either a definitive bacteriological diagnosis and/or imaging studies.

RESULTS

116 adult patients were included with a mean age of 62.75 (14.98) years. Males predominated (68.10%). Eighteen patients (15.51%) were immunosuppressed. The most frequent symptom was back pain (99.14%) followed by fever, which was detected in 45 patients (38.79%). Puncture-aspiration or biopsy was performed in 84 patients (72.10%) and its culture was positive in 48 samples (57.14%). Gram positive species predominated (73.86%) on cultures, followed by Gram negative (12.5%), mycobacteria (10.23%) and fungi (3.41%). No microorganism was identified in 28 patients (24.14%). On imaging, most of the patients (92.24%) had paravertebral or epidural abscess. 63 cases (54.31%) showed vertebral destruction and 39 (33.62%) cord compression. Twenty-two patients (18.97%) required further surgical procedures and 13 (11.21%) died.

CONCLUSIONS

The average patient is middle aged (often male) with a history of subacute back pain, sometimes presenting fever and/or neurological damage on diagnosis. Acute phase reactants are frequently raised. Diabetes mellitus, endocarditis and immunosuppressed patients may have the worst chance of a good outcome, therefore these patients should be more carefully managed (always try to obtain an imaging-guided biopsy, correct antibiotic treatment, and a functional and clinical follow-up).

Microbial Etiology of Pyogenic Vertebral Osteomyelitis According to Patient Characteristics

Background

It is difficult to select an appropriate empirical antibiotic treatment regimen for patients with culture-negative pyogenic vertebral osteomyelitis (PVO). Having knowledge of the distribution of microorganisms according to patient characteristics can help clinicians make informed choices regarding empirical antibiotics. The aim of this study was to determine the microbial distribution among individuals with PVO according to their demographic and clinical characteristics.

Methods

We reviewed the medical records of patients admitted to our hospital with culture-confirmed PVO between January 2005 and December 2017 and collected data on demographics, underlying diseases, and radiographic and microbiological results. Statistical analysis was performed to identify associations between specific bacteria and specific patient characteristics.

Results

A total of 586 patients were included in the study. The prevalence of Staphylococcus aureus infections was higher in young patients than in old patients, while gram-negative bacterial infections and Enterococcus were more prevalent in older patients. Gram-negative bacterial infections were more common in women than in men (32.1% vs 16.4%; P < .05), in patients with cirrhosis than in those without (32.7% vs 21.1%; P < .05), and in patients with a solid tumor than in those without (31.0% vs 20.7%; P < .05). Methicillin-resistant S. aureus infections were more prevalent in patients with chronic renal disease than in those without (34.4% vs 14.7%; P < .05).

Conclusions

The microbial etiology of PVO varies according to patient characteristics. Patient characteristics should thus be considered when choosing empirical antibiotics in patients with culture-negative PVO.

Lemierre's syndrome: A forgotten and re-emerging infection

Lemierre's syndrome, also known as post-anginal septicemia or necrobacillosis, is characterized by bacteremia, internal jugular vein thrombophlebitis, and metastatic septic emboli secondary to acute pharyngeal infections. Modern physicians have "forgotten" this disease. The most common causative agent of Lemierre's syndrome is Fusobacterium necrophorum, followed by Fusobacterium nucleatum and anaerobic bacteria such as streptococci, staphylococci, and Klebsiella pneumoniae. The causative focus mostly originated from pharyngitis or tonsillitis, accounting for over 85% of the cases of Lemierre's syndrome. Pneumonia or pleural empyema is the most common metastatic infection in Lemierre's syndrome. Antimicrobial therapy should be prescribed for 3-6 weeks. The treatment regimens include metronidazole and β-lactam antibiotics. In recent years, the antibiotic stewardship program has resulted in decreased antibiotic prescription for upper respiratory tract infections. The incidence of Lemierre's syndrome has increased over the past decade. F. necrophorum is an underestimated cause of acute pharyngitis or tonsillitis. A high index of suspicion is required for the differential diagnosis of acute tonsillopharyngitis with persistent neck pain and septic syndrome.

Comparative outcomes of operative relative to medical management of spondylodiscitis accounting for frailty status at presentation

PURPOSE

Investigate outcomes in a spondylodiscitis (SD) patient cohort undergoing operative and medical treatment or medical treatment alone, accounting for frailty status at presentation.

METHODS

Patients >18 years old undergoing treatment for SD were retrospectively analyzed. The diagnosis of SD was made through a combination of clinical findings, MRI/CT findings, and blood/tissue cultures. Those who failed to respond to antibiotics, had deteriorating markers, or developed neurologic compromise were considered operative candidates. Patients were stratified based on operative (Op, operative plus medical management) or conservative (Cons, medical only) treatment. Univariate analyses identified differences in outcome measures across treatment groups. Conditional forward regression equations, controlling for patient age, identified predictors of increased mortality and inferior outcomes.

RESULTS

116 patients with SD were included. 73 underwent Cons treatment and 43 were Op. Op patients were significantly younger (62.9vs70.7yrs; p < 0.001) and less frail (1.09vs1.85; p < 0.006) than Cons patients, with significantly higher WCC and ESR. Cons pts had higher rates of isolated SD, but Op pts had higher rates of SD with associated SEA, VOM, psoas abscess, and para-vertebral abscess (all p < 0.05). Op pts had significantly lower 30-day mortality than Cons pts (2.3%vs17.8%, p = 0.016), and trended lower 1Y mortality (11.6%vs20.5%, p = 0.310) with similar SD recurrence rates (11.6%vs16.4%, p = 0.592). Patients with an mFI > 3 had significantly higher 30-day mortality (30.4% vs 7.5%, p = 0.003) and trended higher 1-year mortality regardless of intervention.

CONCLUSIONS

Operative intervention was associated with lower 30-day mortality significantly and 1-year mortality compared to conservative treatment, while an increased mFI was associated with higher short-term mortality.

First-4-week erythrocyte sedimentation rate variability predicts erythrocyte sedimentation rate trajectories and clinical course among patients with pyogenic vertebral osteomyelitis

BACKGROUND

The trajectory pattern of erythrocyte sedimentation rate (ESR) in patients with pyogenic vertebral osteomyelitis (PVO) and its clinical significance is unclear. We further evaluated whether the first-4-week ESR variability can predict the trajectory pattern, treatment duration and recurrence of PVO.

METHODS

The longitudinal ESR patterns of adults with PVO within the first 6 months were characterized through group-based trajectory modeling (GBTM). The ESR variability within the first 4 weeks was defined using the absolute difference (AD), coefficient of variation, percent change, and slope change. The first-4-week ESR variabilities were analyzed using ordinal logistic regression to predict the 6-month ESR trajectory and using logistic regression to predict treatment duration and recurrence likelihood. The discrimination and calibration of the prediction models were evaluated.

RESULTS

Three ESR trajectory patterns were identified though GBTM among patients with PVO: Group 1, initial moderate high ESR with fast response; Group 2, initial high ESR with fast response; Group 3, initial high ESR with slow response. Group 3 patients (initial high ESR with slow response) were older, received longer antibiotic treatment, and had more comorbidities and higher recurrence rates than patients in the other two groups. The initial ESR value and ESR - AD could predict the 6-month ESR trajectory. By incorporating the first-4-week ESR variabilities and the clinical features of patients, our models exhibited moderate discrimination performance to predict prolonged treatment (≥12 weeks; C statistic, 0.75; 95% confidence interval [CI], 0.70 to 0.81) and recurrence (C statistic, 0.69; 95% CI, 0.61 to 0.78).

CONCLUSIONS

The initial ESR value and first-4-week ESR variability are useful markers to predict the treatment duration and recurrence of PVO. Future studies should validate our findings in other populations.

[Differential diagnosis of axial spondyloarthritis-axSpA mimics]

The classification of axial spondyloarthritis (axSpA) comprises the classical ankylosing spondylitis (AS), which is characterized by already existing structural changes in the sacroiliac joints, and the so-called non-radiographic axSpA (nr-axSpA), in which by definition such changes are not present. This distinction is based on the ASAS classification criteria for axSpA, which are however not suitable for a diagnosis. According to the current classification, spondyloarthritis (SpA) includes axSpA, which can be associated with psoriasis and/or chronic inflammatory bowel diseases (CED), such as Crohn's disease and ulcerative colitis, and peripheral SpA, which is further divided into SpA associated with psoriasis, partially synonymous with psoriatic arthritis (PsA), reactive SpA, partially synonymous with reactive arthritis (ReA) and SpA associated with CED, partially synonymous with arthritis associated with CED (e.g. Crohn's disease, ulcerative colitis) and peripheral undifferentiated SpA, which by definition is not associated with any of the above. In this article only the most important differential diagnoses are discussed, i. e. diffuse idiopathic skeletal hyperostosis (DISH), fractures and infections in the axial skeleton. In addition, the frequency of certain musculoskeletal findings in the normal population examined by magnetic resonance imaging (MRI) are also discussed.

Burkholderia cepacia as a cause of pyogenic spondylodiscitis in immunocompetent patients: a single-institution case series and literature review

Burkholderia cepacia is an important pathogen of humans in both immunocompromised and hospitalized patients. This uncommon pathogen is established to be the cause of pyogenic spondylodiscitis in only seven cases in the medical literature. Here, we report the cases of four patients who were diagnosed over two years period with Burkholderia cepacia spondylodiscitis and were successfully managed by appropriate antimicrobial treatment after open surgical biopsy was done for debridement and microbiological identification.

Hypervirulence and carbapenem resistance: two distinct evolutionary directions that led high-risk Klebsiella pneumoniae clones to epidemic success

Introduction: Over the past few decades, Klebsiella pneumoniae has become a significant threat to public health and is now listed as an ESKAPE pathogen. Evolving with versatile capabilities, K. pneumoniae is a population composed of genetically and phenotypically diverse bacteria. However, epidemic K. pneumoniae are restricted to specific clonal lineages. The clonal group CG23 comprises hypervirulent K. pneumoniae displaying limited resistance to antimicrobials and is frequently associated with the community-acquired invasive syndrome. On the other hand, CG258 is another clonal group of K. pneumoniae that has evolved resistance to carbapenems, primarily by acquiring the carbapenemase-encoding genes through nosocomial carriage. Areas covered: With a focus on the high-risk K. pneumoniae clonal lineages CG23 and CG258, we review recent advances including the newly discovered lineage-specific genomic features, and the molecular basis of K. pneumoniae-associated epidemiology, antimicrobial resistance, and hypervirulence. Expert opinion: Both CG23 and CG258 can establish reservoirs in susceptible individuals. Empirical antimicrobial regimens that are prescribed for immediate treatments frequently create selective pressures that favor the high-risk lineages to develop into prominent colonizers. This dilemma reinforces the need for effective therapies that require rapid and accurate diagnosis of epidemic K. pneumoniae.

Pyogenic Vertebral Column Osteomyelitis in Adults: Analysis of Risk Factors for 30-Day and 1-Year Mortality in a Single Center Cohort Study

Study Design

Retrospective cohort study.

Purpose

To describe our experience in the management and outcomes of vertebral column osteomyelitis (VCO), particularly focusing on the risk factors of early and late mortality.

Overview of Literature

Previous reports suggest a global increase in spinal column infections highlighting significant morbidity and mortality. To date, there have been no reports from our local population, and no previous report has assessed the potential relationship of frailty with mortality in a cohort of patients with VCO.

Methods

We reviewed 76 consecutive patients with VCO between 2009 and 2016 in Waikato Hospital, New Zealand. Demographic, clinical, microbiological, and treatment data were collected. Comorbidities were noted to calculate the modified Frailty Index (mFI). Mortality at 30 days and 1 year was recorded. Univariate and multivariate analyses were used to identify the predictors of mortality.

Results

The mean age of patients was 64.1 years, with 77.6% being male. Most patients presented with axial back pain (71.1%), with the lumbar spine most commonly affected (46%). A mean of 2.1 vertebral bodies was involved. Methicillin-sensitive Staphylococcus aureus was the most common organism of infection (35.5%), and 15.8% of patients exhibited polymicrobial infection. Twenty patients (26.3%) underwent surgical intervention, which was more likely in patients with concomitant spinal epidural abscess (odds ratio [OR], 4.88) or spondylodiscitis (OR, 3.81). Mortality rate was 5.2% at 30 days and 22.3% at 1 year. The presence of frailty (OR, 13.62) and chronic renal failure (OR, 13.40) elevated the 30-day mortality risk only in univariate analysis. An increase in age (OR, 1.07) and the number of vertebral levels (OR, 2.30) elevated the 1-year mortality risk in both univariate and multivariate analyses.

Conclusions

Although the mFI correlated with 30-day mortality in univariate analysis, it was not a significant predictor in multivariate analysis. An increase in age and the number of levels involved elevated the 1-year mortality risk.

Selection of an appropriate empiric antibiotic regimen in hematogenous vertebral osteomyelitis

Background

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

Method

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

Results

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

Conclusions

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

Short- versus long-course antibiotics in osteomyelitis: A systematic review and meta-analysis

Current practice of long-term antibiotic use in patients with osteomyelitis is controversial. Recent studies showed short-term antibiotic use to be non-inferior to long-term use, but the results of these studies have been inconsistent. In this review, the PubMed and Embase databases were searched from inception through to June 2018 for randomised controlled trials (RCTs), cohort studies or case-control studies comparing two different durations of antibiotic use. Short antibiotic courses were defined as antibiotics administered for a shorter period than the recommended 4-6 weeks. A random-effects model was used to calculate summary odds ratios (ORs) of treatment failure in patients treated with short-course antibiotics compared with long-course antibiotics. A total of 15 articles (5 RCTs and 10 observational studies) and 3598 patients were included. The overall OR of treatment failure in patients receiving short-course antibiotics was 1.50 [95% confidence interval (CI) 0.97-2.34]. Subgroup analysis revealed that a short course of antibiotic treatment was associated with an increased treatment failure rate in vertebral osteomyelitis (OR = 2.06, 95% CI 1.18-3.57) while having a similar rate to a long antibiotic course in acute osteomyelitis of childhood (OR = 1.86, 95% CI 0.75-4.64). Meta-regression found a higher proportion of Staphylococcus aureus infection was related to a higher risk of treatment failure in patients with vertebral osteomyelitis (Coef. = 4.996; P = 0.032). Short-course antibiotics are safe and effective in children with acute osteomyelitis. Long-course antibiotics may still be preferred in vertebral osteomyelitis, especially in patients with S. aureus infection.

Antibiotic Treatment of Vertebral Osteomyelitis caused by Methicillin-Susceptible Staphylococcus aureus: A Focus on the Use of Oral β-lactams

BACKGROUND

Vertebral osteomyelitis (VO) is a rare but serious condition, and a potentially significant cause of morbidity. Methicillin-susceptible Staphylococcus aureus (MSSA) is the most common microorganism in native VO. Long-term administration of parenteral and oral antibiotics with good bioavailability and bone penetration is required for therapy. Use of oral β-lactams against staphylococcal bone and joint infections in adults is not generally recommended, but some experts recommend oral switching with β-lactams. This study aimed to describe the current status of antibiotic therapy and treatment outcomes of oral switching with β-lactams in patients with MSSA VO, and to assess risk factors for treatment failure.

MATERIALS AND METHODS

This retrospective study included adult patients with MSSA VO treated at nine university hospitals in Korea between 2005 and 2014. Treatment failure was defined as infection-related death, microbiological relapse, neurologic deficits, or unplanned surgical procedures. Clinical characteristics and antibiotic therapy in the treatment success and treatment failure groups were compared. Risk factors for treatment failure were identified using the Cox proportional hazards model.

RESULTS

A total of 100 patients with MSSA VO were included. All patients were treated, initially or during antibiotic therapy, with one or more parenteral antibiotics. Sixty-nine patients received one or more oral antibiotics. Antibiotic regimens were diverse and durations of parenteral and oral therapy differed, depending on the patient and the hospital. Forty-two patients were treated with parenteral and/or oral β-lactams for a total duration of more than 2 weeks. Compared with patients receiving parenteral β-lactams only, no significant difference in success rates was observed in patients who received oral β-lactams for a relatively long period. Sixteen patients had treatment failure. Old age (adjusted hazard ratio [HR] 5.600, 95% confidence interval [CI] 1.402 - 22.372, P = 0.015) and failure to improve C-reactive protein levels at follow-up (adjusted HR 3.388, 95% CI 1.168 - 9.829, P = 0.025) were independent risk factors for treatment failure.

CONCLUSION

In the study hospitals, diverse combinations of antibiotics and differing durations of parenteral and oral therapy were used. Based on the findings of this study, we think that switching to oral β-lactams may be safe in certain adult patients with MSSA VO. Since limited data are available on the efficacy of oral antibiotics for treatment of staphylococcal VO in adults, further evaluation of the role of oral switch therapy with β-lactams is needed.

Native vertebral osteomyelitis in aged patients: distinctive features. An observational cohort study

PURPOSE

To describe the demographic, clinical, and microbiological profile of native vertebral osteomyelitis (NVO) in aged patients as compared to that of younger patients, to identify differences that could motivate changes in clinical management.

METHODS

Retrospective, observational cohort study (1990-2015) including all adult patients with microbiologically confirmed NVO divided into 2 groups: aged (≥ 65 years) vs younger (18-64 years).

RESULTS

247 patients included, 138 aged and 109 younger. Relative to younger patients, the aged had higher rates of healthcare-related infection (40.6 vs 25.7%, p = 0.014), previous known heart valve disease (29.7 vs 9.2%, p < 0.001), and concomitant infective endocarditis (38.4 vs 20.2%, p = 0.002). The groups showed similar rates of symptomatic spinal cord compression (14.5 vs 11.9%, p = 0.556) and paraspinal abscesses (62.3 vs 68.8%, p = 0.288) at presentation. There was a trend to lower spine surgery rates in the aged (11.6 vs 17.4%, p = 0.192). On univariate analysis, Staphylococcus aureus infection was associated with higher in-hospital mortality in aged (29%, OR 4.3, 95% CI 1.61-11.45). In-hospital mortality was higher among the aged (14.5 vs 6.4%, p = 0.044) as well as relapse rate due to treatment failure (3.4 vs 1%, p = 0.377).

CONCLUSIONS

The findings underscore the importance of preventing healthcare-related infection and maintaining high clinical suspicion of infective endocarditis in aged NVO patients to implement proper management. S. aureus infection had a poorer prognosis in this population. As compared to younger patients, spinal surgery rates were slightly lower and overall prognosis poorer in the aged, despite similar rates of symptomatic spinal cord compression and abscesses at presentation.

Chronic dialysis patients with infectious spondylodiscitis have poorer outcomes than non-dialysis populations

Purpose

Infectious spondylodiscitis is a serious disease that can lead to permanent neurological deficit. Because there were only a few case reports or series featuring infectious spondylodiscitis in chronic dialysis patients, we investigated the epidemiology and outcome in the chronic dialysis patients versus general population.

Materials and methods

We retrospectively identified chronic dialysis patients admitted for infectious spondylodiscitis between January 2002 and December 2015. A total of 105 chronic dialysis patients were included, and we performed a 1:2 case-control match on propensity score in non-dialysis patients with infectious spondylodiscitis. The demographic features, clinical manifestation, infection focus, and disease outcome were recorded.

Results

A total of 302 patients entered the final analysis. Chronic dialysis patients less frequently had fever (34.3%), and in the majority, bacterial entry was through dialysis vascular access (30.5%). Methicillin-resistant Staphylococcus aureus (MRSA) comprised the majority of causative pathogen. The chronic dialysis group had longer hospital stay, higher in-hospital mortality, and higher 1-year mortality. The odds ratio of in-hospital mortality was 2.20 compared with the non-dialysis group.

Conclusions

The study highlighted poorer outcome and high frequency of resistant Staphylococcus of infectious spondylodiscitis in chronic dialysis patients. Therefore, high vigilance, prompt recognition, and empiric coverage of MRSA will be important in the management of infectious spondylodiscitis in chronic dialysis patients.