Antimicrobial therapy and assessing therapeutic response in culture-negative pyogenic vertebral osteomyelitis: a retrospective comparative study with culture-positive pyogenic vertebral osteomyelitis

Risk Factors Preventing Identification of the Microorganism Causing Vertebral Osteomyelitis

STUDY DESIGN

Retrospective study.

OBJECTIVE

To elucidate the factors influencing the identification of causative microorganisms in vertebral osteomyelitis (VO) and the effectiveness of different culture methods in increasing the identification rate.

METHODS

A total of 252 patients diagnosed with and treated for VO at a single hospital were enrolled. The results of various culture methods were reviewed along with the clinical data of the patients retrospectively.

RESULTS

Microbiological diagnosis was achieved in 210 out of 252 patients (83.3%). Diagnostic percentages of blood cultures, CT-guided drainage, fluoroscopic disc biopsy, and intraoperative specimens were 73.6%, 73.9%, 27.6%, and 50.8%, respectively. Staphylococcus aureus was the most common pathogen (85 cases, 40.5%). Higher White Blood Cell (WBC) count, lower serum albumin (ALB) level, epidural abscess, and absence of prior antibiotic exposure were significant predictors of positive culture results across all culture methods. Prior antibiotic exposure was the most significant predictor of negative outcomes (OR 0.24). Blood culture results correlated with body temperature, C-reactive protein (CRP), ALB, and prior antibiotic exposure. A shorter duration of antibiotic administration before culture was associated with an increased likelihood of positive blood culture results.

CONCLUSIONS

This study demonstrated that laboratory findings indicating a high inflammatory response (elevated WBC count, CRP level, and body temperature), lower ALB level, presence of epidural abscess, absence of prior antibiotic exposure, and shorter duration of antibiotics were significant predictors of positive culture results. Blood cultures should be conducted in the presence of high inflammation levels to improve microorganism identification rates.

Analysis of factors affecting the clinical management of infection in culture-negative patients following percutaneous endoscopic decompression: a retrospective study

Background

Culture-negative spinal infections after prophylactic antibiotic use in percutaneous endoscopic decompression are rare, and diagnostic difficulties and the risk of antibiotic-resistant infections complicate treatment. This study retrospectively analyzed the medical records of culture-negative patients following percutaneous endoscopic surgery to identify risk factors influencing antimicrobial therapy and provide insights for clinical management.

Methods

Data were retrospectively collected from patients who underwent lumbar percutaneous endoscopic decompression at the Affiliated Hospital of Qingdao University between January 2014 and June 2023. The patients' medical records were reviewed. Patient demographics, hidden blood loss, daily blood glucose control, and maximum temperature during treatment were recorded as potential risk factors. C-reactive protein, procalcitonin, white blood cells, erythrocyte sedimentation rate, and the duration of antibiotic treatment were used as indicators of infection treatment. The impact of these risk factors on infection was then analyzed.

Results

The results showed that blood glucose control was strongly correlated with the severity of infection (Beta = 0.60, P = 0.00), strongly correlated with short-term treatment effectiveness (Beta = 0.65, P = 0.00), and moderately correlated with the duration of antibiotic treatment (Beta = 0.41, P = 0.01). Hidden blood loss was moderately correlated with the severity of infection (Partial-R = 0.49, P = 0.00) and moderately correlated with the duration of antibiotic treatment (Partial-R = 0.48, P = 0.00). Hidden blood loss index was moderately correlated with the duration of antibiotic treatment (Partial-R = 0.50, P = 0.00). Female was a favorable factor to shorten the duration of antibiotic treatment (Beta = -0.25, P = 0.01), and higher maximum temperature during infection may indicate a longer duration of antibiotic treatment (Beta = 0.28, P = 0.02).

Conclusion

Our findings suggest that healthy blood glucose levels, a lower hidden blood loss and hidden blood loss index might help reduce the duration of antibiotic use after infection. Effective hemostasis during surgery to reduce hidden blood loss and good preoperative blood glucose control indicators are both beneficial measures for infection treatment.

Impact of causative organism identification on clinical outcomes after minimally invasive posterior fixation for thoracolumbar pyogenic spondylitis: multicenter retrospective cohort study

PURPOSE

This study aimed to evaluate the difference in treatment duration and unplanned additional surgeries between patients with unidentified causative organisms on empiric antibiotics and those with identified organisms on selective antibiotics in treating thoracolumbar pyogenic spondylitis with minimally invasive posterior fixation.

METHODS

This multicenter retrospective cohort study included patients with thoracolumbar pyogenic spondylitis refractory to conservative treatment who underwent minimally invasive posterior fixation. Patients were divided into the identified (known causative organism) and unidentified groups (unknown causative organism). We analyzed data on demographics, antibiotic use, surgical outcomes, and infection control indicators.

RESULTS

We included 74 patients, with 52 (70%) and 22 (30%) in the identified and unidentified groups, respectively. On admission, the identified group had higher C-reactive protein (CRP) levels and more iliopsoas abscesses. The duration to postoperative CRP negative was similar in the identified and unidentified groups (7.13 vs. 6.48 weeks, p = 0.74). Only the identified group had unplanned additional surgeries due to poor infection control, affecting 6 of 52 patients (12%). Advanced age and causative organism identification increased the additional surgery odds (odds ratio [OR], 8.25; p = 0.033 and OR, 6.83; p = 0.034, respectively).

CONCLUSION

The use of empiric antibiotics in minimally invasive posterior fixation was effective without identifying the causative organism and did not prolong treatment duration. In patients with identified organisms, 12% required unplanned additional surgery, indicating a more challenging infection control. Causative organism identification was associated with the need for additional surgery, suggesting a more cautious treatment strategy for these patients.

Efficacy of Additional Surgical Decompression on Functional Outcome in Pyogenic Spinal Epidural Abscess With No Neurological Deficit

Objective

The aim of this study was to investigate the efficacy of additional surgical decompression with antibiotics to treat pyogenic spinal epidural abscess (SEA) with no neurological deficits.

Methods

We retrospectively reviewed the data of patients diagnosed with spontaneous pyogenic SEA in the thoracolumbosacral area who presented with sciatica and no motor deficits in the lower extremities. The treatment took place in a single tertiary hospital. The effects of additional surgical decompression (decompressive laminectomy) and other clinical variables on functional outcome were assessed using the short form 36 (SF-36).

Results

Fifty-nine patients (49 men and 10 women, mean age 65.73±12.29 [41-89] years) were included in the analysis. Surgical decompression had been performed in 31 patients (Group S, treated with additional surgical decompression and antibiotics). There were five (15.2%, 5/33) unplanned operations to control leg sciatica among the patients with initially non-surgical plans, and 28 patients were finally treated with only antibiotics (group N-S). Group S showed a statistically significant increased cost of hospitalization compared to group N-S (15,856.37±7,952.83 vs. 10,672.62±4,654.17 US dollars, p=0.004) with no superiority of 6-month functional outcome after the completion of antibiotic treatment (53.65±4.74 vs. 51.75±7.96 SF-36 scores, p=0.266).

Conclusion

Although there is a possibility of requiring an unplanned operation to control leg sciatica during conservative antibiotic treatment, overall, additional surgical decompression in pyogenic SEA presenting with no motor deficit of the lower extremity showed increased medical burden and no greater benefit in terms of functional outcomes.

Combating antimicrobial resistance in osteoarticular infections: Current strategies and future directions

The emergence of antimicrobial resistance (AMR) has profoundly impacted the management of osteoarticular infections (OAIs), presenting significant challenges for healthcare systems worldwide. This review provides a comprehensive overview of the current landscape of AMR in OAIs, emphasizing the necessity for assertive and innovative strategies to combat this escalating health threat. It discusses the evolution of resistance among key pathogens, including ESKAPEE organisms, and the implications for treatment protocols and healthcare outcomes. The importance of antibiotic stewardship programs (ASPs) is highlighted as a core strategy to optimize antibiotic use and mitigate the development of resistance. Additionally, the review explores the potential of pharmacological approaches, including novel antibiotic regimens and combination therapies, alongside surgical interventions and alternative therapies such as bacteriophage-based treatments and probiotics, in managing these complex infections. The role of rapid diagnostic methods in improving treatment accuracy and the critical need for global surveillance to track AMR trends are also examined. By integrating insights from recent literature and expert recommendations, this review underscores the multifaceted approach required to address the challenge of AMR in OAIs effectively. It calls for a concerted effort among clinicians, researchers, and policymakers to foster innovation in treatment strategies, enhance diagnostic capabilities, and implement robust stewardship and surveillance programs. The goal is to adapt to the evolving landscape of OAIs and ensure optimal patient care in the face of rising AMR.

Culture-Negative Native Vertebral Osteomyelitis: A Narrative Review of an Underdescribed Condition

The incidence of culture-negative NVO (CN-NVO) cases is increasing, presenting significant diagnostic and therapeutic challenges due to the inability to isolate causative organisms with conventional microbiological methods. Factors influencing the diagnosis of CN-NVO include prior antimicrobial therapy, low pathogen burden, fastidious or intracellular organisms, technical issues, and non-infectious mimickers. Diagnosis often relies on imaging modalities like magnetic resonance imaging (MRI) and computed tomography (CT)-guided biopsy, though these methods can sometimes fail to yield positive microbiological results. Advanced diagnostic tools, such as polymerase chain reaction (PCR), metagenomic next-generation sequencing (mNGS), and cell-free DNA analysis, may be necessary to identify the pathogen. The causative pathogen cannot be isolated in some patients, among which an empirical antimicrobial therapy should be initiated. This narrative review discusses the management, monitoring, surgical indications, and outcomes for patients with CN-NVO.

Generation of synthetic PET/MR fusion images from MR images using a combination of generative adversarial networks and conditional denoising diffusion probabilistic models based on simultaneous 18F-FDG PET/MR image data of pyogenic spondylodiscitis

BACKGROUND CONTEXT

Cross-modality image generation from magnetic resonance (MR) to positron emission tomography (PET) using the generative model can be expected to have complementary effects by addressing the limitations and maximizing the advantages inherent in each modality.

PURPOSE

This study aims to generate synthetic PET/MR fusion images from MR images using a combination of generative adversarial networks (GANs) and conditional denoising diffusion probabilistic models (cDDPMs) based on simultaneous 18F-fluorodeoxyglucose (18F-FDG) PET/MR image data.

STUDY DESIGN

Retrospective study with prospectively collected clinical and radiological data.

PATIENT SAMPLE

This study included 94 patients (60 men and 34 women) with thoraco-lumbar pyogenic spondylodiscitis (PSD) from February 2017 to January 2020 in a single tertiary institution.

OUTCOME MEASURES

Quantitative and qualitative image similarity were analyzed between the real and synthetic PET/ T2-weighted fat saturation MR (T2FS) fusion images on the test data set.

METHODS

We used paired spinal sagittal T2FS and PET/T2FS fusion images of simultaneous 18F-FDG PET/MR imaging examination in patients with PSD, which were employed to generate synthetic PET/T2FS fusion images from T2FS images using a combination of Pix2Pix (U-Net generator + Least Squares GANs discriminator) and cDDPMs algorithms. In the analyses of image similarity between the real and synthetic PET/T2FS fusion images, we adopted the values of mean peak signal to noise ratio (PSNR), mean structural similarity measurement (SSIM), mean absolute error (MAE), and mean squared error (MSE) for quantitative analysis, while the discrimination accuracy by three spine surgeons was applied for qualitative analysis.

RESULTS

Total of 2,082 pairs of T2FS and PET/T2FS fusion images were obtained from 172 examinations on 94 patients, which were randomly assigned to training, validation, and test data sets in 8:1:1 ratio (1664, 209, and 209 pairs). The quantitative analysis revealed PSNR of 30.634 ± 3.437, SSIM of 0.910 ± 0.067, MAE of 0.017 ± 0.008, and MSE of 0.001 ± 0.001, respectively. The values of PSNR, MAE, and MSE significantly decreased as FDG uptake increased in real PET/T2FS fusion image, with no significant correlation on SSIM. In the qualitative analysis, the overall discrimination accuracy between real and synthetic PET/T2FS fusion images was 47.4%.

CONCLUSIONS

The combination of Pix2Pix and cDDPMs demonstrated the potential for cross-modal image generation from MR to PET images, with reliable quantitative and qualitative image similarities.

Determining the prevalence and risk factors for positive bacterial culture in canine discospondylitis: 120 cases

BACKGROUND

Identification of the aetiologic agent in canine discospondylitis is infrequent; and risk factors for a positive bacterial culture have not previously been reported.

METHODS

Medical records at three institutions were searched to identify clinical features of dogs with discospondylitis diagnosed via radiography or cross-sectional imaging. Inclusion in this retrospective case-control study required culture of one or more samples. Multivariable binary logistic regression identified features associated with a positive culture.

RESULTS

Fifty (42%) of 120 dogs had one or more positive culture results obtained from either urine (28/115), blood (25/78), intervertebral disc aspiration (10/34) or cerebrospinal fluid (1/18). A positive culture was associated with higher bodyweight (p = 0.002, odds ratio [OR] = 1.054, 95% confidence interval [CI]: 1.019-1.089), more sample types cultured (p = 0.037, OR = 1.806, 95% CI: 1.037-3.147) and institution (p = 0.021). The presence of possibly associated preceding events (e.g., surgery), pyrexia, number of disc sites affected and serum C-reactive protein result, among other features, were not statistically significant.

LIMITATIONS

All isolates cultured were included since differentiation of true aetiologic agents from contaminants was not possible without histological confirmation and culture from surgical or postmortem biopsies.

CONCLUSIONS

Clinical features typically associated with infection were not identified as risk factors for positive culture in canine discospondylitis. The statistical significance of the institution suggests that standardisation of sampling protocols is necessary.

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.

Analysis of Clinical Factors Associated with Medical Burden and Functional Status in Pyogenic Spine Infection

Background and purpose: Pyogenic spinal infection (PSI) has recently been on the rise due to aging and increasing degenerative spinal disease related procedures. PSI requires long-term antibiotic treatment and is followed by sustained functional disability even after successful treatment. This study aimed to analyze the clinical factors associated with medical burden and functional status of PSI. Methods: This retrospective study involved patients with non-postoperative PSI of thoraco-lumbo-sacral area in a single tertiary hospital. The length/cost of hospitalization with an antibiotic therapy and severity of back pain using the short form 36 (SF-36) were defined as the medical burden and functional status, respectively. We analyzed the clinical factors associated with medical burden and functional status. Results: We enrolled 142 patients (91 males and 51 females). The length and cost of hospitalization were 55.56 ± 27.09 (7–172) days and $14,070.17 ± 9289.39 (1611.87–48,722.35), respectively. A recurrence rate of 7.7% (11/142) and significant improvement of SF-36 at six months after completion of antibiotic treatment were noted (p < 0.05). Procedure-related (OR 2.702), C-reactive protein (CRP; OR 1.062), bacteremia (OR 4.966), additional surgical treatment (OR 6.524), recurrence (OR 12.453), and paraspinal abscess (OR 5.965) for above-average length of hospitalization were observed; female (OR 4.438), CRP (OR 1.071), bacteremia (OR 4.647), additional surgical treatment (OR 6.737), recurrence (OR 22.543), and extent of lesion (OR 1.431) for above-average cost of hospitalization; leg weakness (OR 15.966), white blood cell (WBC; OR 1.116), Charlson’s comorbidity index (CCI, OR 1.485), and identification of causative bacteria (OR 2.913) for below-average initial SF-36 were observed; leg weakness (OR 7.975) and WBC (OR 1.094) for below-average 6-month SF-36 were the statistically significant clinical factors in the multivariable logistic regression analysis (p < 0.05). Conclusion: Recurrence and leg weakness were identified as the most important clinical factors for medical burden and functional status in PSI, respectively. We think that it is necessary to actively suppress recurrence and manage neurological deficits for decreasing medical burden and achieving favorable functional outcome in the treatment of PSI.

Assessment of Therapeutic Responses Using a Deep Neural Network Based on 18F-FDG PET and Blood Inflammatory Markers in Pyogenic Vertebral Osteomyelitis

Background and Objectives: This study investigated the usefulness of deep neural network (DNN) models based on ¹⁸F-fluorodeoxyglucose positron emission tomography (FDG-PET) and blood inflammatory markers to assess the therapeutic response in pyogenic vertebral osteomyelitis (PVO). Materials and Methods: This was a retrospective study with prospectively collected data. Seventy-four patients diagnosed with PVO underwent clinical assessment for therapeutic responses based on clinical features during antibiotic therapy. The decisions of the clinical assessment were confirmed as ‘Cured’ or ‘Non-cured’. FDG-PETs were conducted concomitantly regardless of the decision at each clinical assessment. We developed DNN models depending on the use of attributes, including C-reactive protein (CRP), erythrocyte sedimentation ratio (ESR), and maximum standardized FDG uptake values of PVO lesions (SUV_max), and we compared their performances to predict PVO remission. Results: The 126 decisions (80 ‘Cured’ and 46 ‘Non-cured’ patients) were randomly assigned with training and test sets (7:3). We trained DNN models using a training set and evaluated their performances for a test set. DNN model 1 had an accuracy of 76.3% and an area under the receiver operating characteristic curve (AUC) of 0.768 [95% confidence interval, 0.625–0.910] using CRP and ESR, and these values were 79% and 0.804 [0.674–0.933] for DNN model 2 using ESR and SUV_max, 86.8% and 0.851 [0.726–0.976] for DNN model 3 using CRP and SUV_max, and 89.5% and 0.902 [0.804–0.999] for DNN model 4 using ESR, CRP, and SUV_max, respectively. Conclusions: The DNN models using SUV_max showed better performances when predicting the remission of PVO compared to CRP and ESR. The best performance was obtained in the DNN model using all attributes, including CRP, ESR, and SUV_max, which may be helpful for predicting the accurate remission of PVO.

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

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

Non-specific spondylodiscitis: a new perspective for surgical treatment

PURPOSE

Pyogenic spondylodiscitis is a relatively rare spinal disease; non-specific spondylodiscitis (NSS) cases are increasing. This study aims to identify if changes of inflammatory markers under antibiotic therapy can be used to determine which NSS patients can benefit from surgical indication earlier than others.

METHODS

Two groups of patients with NSS were examined. Group A underwent surgery, while Group B was treated conservatively. Group B was also subdivided in patients undergoing antibiotic therapy for > 6 weeks (B1) and < 6 weeks (B2). Groups were compared for age, gender, BMI, blood levels of ESR and CRP and VAS scale.

RESULTS

There were no differences (P = 0.06) in reduction in ESR at 4 weeks between two main groups. A reduction in CRP, with < 2.7 mg/dl at 4 weeks, was observed in Group A (P = 0.01). Comparing Group B1 to B2, a reduction (P = 0.0001) in VAS, ESR and CRP at 4 weeks was observed in Group B2. It was possible to isolate the pathogen in 52.8% of Group B, without any differences on VAS, ESR and CRP values and on length of the antibiotic therapy.

CONCLUSIONS

The surgical treatment should be considered for patients who, after 4 weeks of conservative therapy, do not show a reduction in the ESR < 50 mm/h and of the CRP < 2.7 g/dl. The comparison between groups underwent surgically and those treated conservatively showed a reduction in the CRP at 4 weeks and better VAS for pain at 3 months in Group A.

Treatment Guideline for Patients with Native Culture-negative Pyogenic Vertebral Osteomyelitis

BACKGROUND

With the development of evidence-based guidelines for the diagnosis and antibiotic treatment of patients with pyogenic vertebral osteomyelitis, various nonsurgical and surgical treatment strategies have achieved favorable results. However, sufficient administration of appropriate antibiotics is a prerequisite for treatment success, which cannot be guaranteed in patients with culture-negative pyogenic vertebral osteomyelitis. Unfortunately, previous studies on culture-negative pyogenic vertebral osteomyelitis were limited by small patient groups, short follow-up periods, varied treatment protocols, and inconsistently defined clinical endpoints.

QUESTIONS/PURPOSES

Among patients treated according to our center's treatment protocol for culture-negative pyogenic vertebral osteomyelitis, which included patients treated without surgery, with surgery but without spinal instrumentation, as well as patients treated with instrumented surgery, (1) what proportion of patients in each treatment group experienced recurrence (or persistence) of infection, complications of treatment, and death; and (2) what factors were independently associated with recurrent or persistent infection after treatment under this algorithm?

METHODS

This was a retrospective evaluation of a treatment protocol in use at one center from 2008 to 2020. During that time, we treated 183 patients for culture-negative pyogenic vertebral osteomyelitis. The diagnosis was based on clinical, laboratory, and radiological features excluding disease that presents similar features to pyogenic vertebral osteomyelitis. For those patients, our protocol included three possible approaches: nonsurgical treatment, including the use of empirical antibiotics (nonoperative group, n = 82); spinal decompression without instrumentation (noninstrumented group, n = 41); and spinal decompression with instrumentation (instrumented group, n = 60). The indications for each treatment during the period remained relatively consistent. Nonsurgical treatment including empirical antibiotics was applied to all patients according to the specified antibiotic protocol. Spinal decompression without instrumentation was employed when a patient presented substantial or aggravating neurologic deficits or intractable pain from an abscess. Instrumentation was added in patients with mechanical instability before or after spinal decompression. Minimum follow-up to be included in this study was 1 year, and 91% (252 of 277) of patients were accounted for at that time, with no differential loss to follow-up among the study groups (12, five, and four patients missing from the three groups, respectively, at 1 year). Chart review was performed to ascertain the proportion of patients in each group who experienced recurrence, complications, and death. Factors associated with recurrence were assessed across the entire cohort using a multivariable logistic model. We analyzed 1-year recurrence and mortality rates using the Kaplan-Meier method, and their 95% confidence intervals were calculated using the method by Hosmer and Lemeshow.

RESULTS

At 1 year, the recurrence-free survival rate was 87% (95% confidence interval 78% to 93%) in the nonoperative group, 87% (95% CI 72% to 94%) in the noninstrumented group, and 91% (95% CI 80% to 96%) in the instrumented group. The proportion of patients who experienced a major medical complication in each group was 12% (10 of 82), 10% (4 of 41), and 8% (5 of 60), respectively. At 1 year, the survival rate with patient death as the endpoint was 95% (95% CI 88% to 98%) in the nonoperative group, 95% (95% CI 82% to 99%) in the noninstrumented group, and 97% (95% CI 87% to 99%) in the instrumented group. After controlling for potentially confounding variables including age, medical comorbidities, and anatomical involvement of infection, the following factors were independently associated with increased odds of infection recurrence or persistence: higher Charlson Comorbidity Index (CCI) score (odds ratio 1.6 per point on the CCI [95% CI 1.2 to 2.1]; p = 0.004) and the presence of a psoas abscess (OR 4.7 [95% CI 1.6 to 13.9]; p = 0.005).

CONCLUSION

Among patients with negative initial nonoperative culture results, spinal decompression and abscess drainage can be used in those with substantial or aggravating neurological deficits or intractable pain caused by an abscess, while additional early spinal instrumentation can be applied upon consideration of their medical comorbidities and the presence of a psoas abscess when mechanical instability is present before or after the spinal decompression. Reasonable clinical results can be expected, regardless of the results from subsequent operative cultures. However, our study results should be replicated by other centers, and further studies that consider individual differences such as bone mineral density and include patients with previous spinal instrumentation or recurrent infection should be performed to establish a more comprehensive treatment protocol.

LEVEL OF EVIDENCE

Level IV, therapeutic study.

Ultrasound evaluation of inflammation in patients with chronic recurrent multifocal osteomyelitis involving the mandible: report of three cases

Chronic recurrent multifocal osteomyelitis (CRMO) is aseptic and can be diagnosed by excluding other diseases, such as bacterial osteomyelitis, scurvy, metabolic disorders, and malignant diseases; therefore, bone biopsy is usually performed to confirm the diagnosis. To prevent misdiagnosis, the appropriate timing and location for biopsy should be determined from an active phase of inflammation. We presented 3 cases of CRMO involving the mandible: Case 1: A 2-year-old girl diagnosed with CRMO in the chronic phase. A sonogram showed a slightly low echoic area adjacent to the bone cortex. Pathological examination revealed a slight accumulation of leukocytes and plasma cells, as well as predominant fibrous stroma. Case 2: A 9-year-old girl diagnosed with CRMO with massive new osteoid formation. A sonogram showed a massive inhomogeneous low echoic area adjacent to the bone cortex. Pathological examination revealed massive osteoid formation and scattered inflammatory cells infiltration. Case 3: A 3-year-old girl diagnosed with CRMO in the active phase. A sonogram showed a massive hypoechoic area adjacent to the bone cortex and hyperechogenicity associated with a muscular and subcutaneous edema. Pathological examination revealed massive bone destruction and neutrophils infiltration within damaged osteoid. Ultrasound was able to visualize the degree of inflammation in the mandible corresponding to that of the surrounding soft tissue in all 3 cases. Therefore, ultrasound would be useful in determining the appropriate timing and location for bone biopsy.

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

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

Neurosurgical Management and Outcome Parameters in 237 Patients with Spondylodiscitis

Surgical treatment of spondylodiscitis allows for rapid mobilization and shortens hospital stays, which makes surgical treatment the first-line therapy. We aim to describe our experiences with operative treatment on spondylodiscitis and to determine the parameters that are important in the prediction of outcomes. A retrospective review identified 237 patients who were operatively treated for spondylodiscitis in our institution between January 2010 and December 2018. Clinical data were collected through review of electronic records and relevant imaging. In all cases, contrast-enhancing MRI from the infected region of the spine was obtained. Leukocyte count and C-reactive protein concentrations (CRP) were determined in all the patients. We included 237 patients in the study, 87 female (36.7%) and 150 male (63.3%), with a mean age of 71.4 years. Mean follow-up was 31.6 months. Forty-five patients had spondylodiscitis of the cervical, 73 of the thoracic, and 119 of the lumbosacral spine. All the patients with spondylodiscitis of the cervical spine received instrumentation. In thoracic and lumbar spine decompression, surgery without instrumentation was performed in 26 patients as immediate surgery and in a further 28 patients in the early stages following admission, while 138 patients received instrumentation. Eighty-nine patients (37.6%) had concomitant infections. Infection healing occurred in 89% of patients. Favorable outcomes were noted in patients without concomitant infections, with a normalized CRP value and in patients who received antibiotic therapy for more than six weeks (p < 0.05). Unfavorable outcomes were noted in patients with high CRP, postoperative spondylodiscitis, and recurrent spondylodiscitis (p < 0.05). Application of antibiotic therapy for more than six weeks and normalized CRP showed a correlation with favorable outcomes, whereas concomitant infections showed a correlation with unfavorable outcomes. A detailed screening for concomitant infectious diseases is recommended.