Treatment outcomes in patients with pyogenic vertebral osteomyelitis who have cirrhosis

Recurrence rate after posterior percutaneous screw fixation without anterior debridement for pyogenic spondylitis compared with conservative treatment: a propensity score-matched analysis

PURPOSE

Previous studies have shown that percutaneous pedicle screw (PPS) posterior fixation without anterior debridement for pyogenic spondylitis can improve patient quality of life compared with conservative treatment. However, data on the risk of recurrence after PPS posterior fixation compared with conservative treatment is lacking. The aim of this study was to compare the recurrence rate of pyogenic spondylitis after PPS posterior fixation without anterior debridement and conservative treatment.

METHODS

The study was conducted under a retrospective cohort design in patients hospitalized for pyogenic spondylitis between January 2016 and December 2020 at 10 affiliated institutions. We used propensity score matching to adjust for confounding factors, including patient demographics, radiographic findings, and isolated microorganisms. We estimated hazard ratios (HRs) and 95% confidence intervals (CIs) for recurrence of pyogenic spondylitis during the follow-up period in the matched cohort.

RESULTS

148 patients (41 in the PPS group and 107 in the conservative group) were included. After propensity score matching, 37 patients were retained in each group. PPS posterior fixation without anterior debridement was not associated with an increased risk of recurrence compared with conservative treatment with orthosis (HR, 0.80; 95% CI, 0.18-3.59; P = 0.77).

CONCLUSIONS

In this multi-center retrospective cohort study of adults hospitalized for pyogenic spondylitis, we found no association in the incidence of recurrence between PPS posterior fixation without anterior debridement and conservative treatment.

The epidemiology of concurrent infection in patients with pyogenic spine infection and its association with early mortality: A nationwide cohort study based on 10,695 patients

BACKGROUND

Generally, a sufficient duration of relevant antibiotics based on an appropriate culture combined with proper surgical treatment guarantees a favorable clinical outcome in patients with pyogenic spine infections. However, a patient's condition often deteriorates as concurrent infections occur in other organs, leading to mortality. Therefore, this study aimed to investigate the epidemiology of concurrent infections in patients with a pyogenic spine infection and estimate the rates and risks of early mortality.

METHODS

Patients with a pyogenic spine infection were identified using a national claims database that includes the entire population. The epidemiology of the six types of concurrent infections was investigated, and the corresponding early mortality rates and risks were estimated. The results were validated internally by bootstrapping and externally by defining two additional cohorts for sensitivity analysis.

RESULTS

Among 10,695 patients with a pyogenic spine infection, the prevalence of the six types of concurrent infections was 11.3 % for urinary tract infections, 9.4 % for intra-abdominal infections, 8.5 % for pneumonia, 4.6 % for septic arthritis or osteomyelitis of the extremities, 0.7 % for central nervous system infections, and 0.5 % for cardiac infections. Patients with a concurrent infection had approximately 4-fold greater mortality than those without (3.3 % vs. 0.8 %). The early mortality rates were particularly higher in patients with multiple or specific types of concurrent infections, including central nervous system infections, cardiac infections, and pneumonia. In addition, the mortality trends differed significantly according to the number and type of concurrent infections.

CONCLUSIONS

These data on six types of concurrent infection among patients with pyogenic spinal infection can be used as a source of reference by clinicians.

Pyogenic spinal infections in patients with chronic liver disease: illustrative case and systematic review

BACKGROUND

Pyogenic spinal infections (PSIs) are a group of uncommon but serious infectious diseases that are characterized by inflammation of the endplate–disc unit. PSIs are considered more prevalent and aggressive among patients with chronic immunocompromised states. Association between PSIs and liver disease has not been systematically analyzed. The authors performed a systematic review to study baseline characteristics, clinical presentation, and mortality of patients with PSI in the setting of chronic liver disease.

OBSERVATIONS

The authors presented the case of a 72-year-old female patient with chronic liver disease who presented with severe low back pain and bilateral lower weakness. Imaging studies showed T10–11 spondylodiscitis. The patient received decompression and fusion surgery with partial neurological improvement. The authors performed a systematic literature search of spondylodiscitis and liver disease, and eight published articles met the studies inclusion and exclusion criteria. These studies featured a total of 144 patients, of whom 129 met inclusion criteria (mean age, 60.5 years, range 40 to 83 years; 62% males). Lumbar infection was the most common report (67%), with Staphylococcus aureus (48%) as the main causative microorganism. Neurological compromise was present in 69% of patients. Surgical intervention occurred in 70.5% of patients, and the average duration of antibiotic treatment was 69.4 days. Postoperative complication rate was 28.5%, with a 30- and 90-day mortality of 17.2% and 24.8%, respectively.

LESSONS

Pyogenic spondylodiscitis in patients with liver disease was associated with a high rate of neurological compromise, postoperative complications, and mortality.

Recurrence Rates and Its Associated Factors after Early Spinal Instrumentation for Pyogenic Spondylodiscitis: A Nationwide Cohort Study of 2148 Patients

Recent studies have consistently reported the safety and effectiveness of early spinal instrumentation for pyogenic spondylodiscitis. However, none of these studies investigated the recurrence rate or associated factors based on this specific group of patients. Recurrence prediction models that are not based on a homogenous cohort of patients undergoing early spinal instrumentation show theoretical limitations for clinical use. A nationwide, population-based, retrospective cohort study using a claims database was planned to investigate the recurrence rate and its associated factors in patients who underwent early instrumented spinal fusion surgery for pyogenic spondylodiscitis. We used data from the Korean National Health Insurance claims database collected between 2014 and 2018. A total of 2148 patients who underwent early (within 6 weeks after the diagnosis) instrumented spinal fusion surgery for pyogenic spondylodiscitis were included, including 1925 patients (90%) without recurrence and 223 patients (10%) with recurrence. Logistic regression models were used to identify factors associated with recurrence, and sensitivity analysis was performed according to two different definitions for recurrence: shorter (2 weeks or more) and longer (6 weeks or more) periods of antibiotic therapy for recurrence. The recurrence rates in our cohort were 14.1%, 10.4%, and 8.0% at 2, 4, and 6 weeks, respectively, in relation to the duration of antibiotic treatment for recurrence. We identified age 60−69 years (OR = 2.42), age > 70 years (OR = 2.29), posterior thoracic approach (OR = 1.85), multiple surgical approaches (OR = 4.17), use of a cage (OR = 1.66), transfusion (OR = 2.55), antibiotics for resistant organisms (OR = 2.55), and systemic steroid treatment over 2 weeks (OR = 2.27) as the factors associated with recurrence. The recurrence rates and associated factors from our first population-based and the largest clinical study can be practically used as a reasonable reference and provide clinicians with an acceptable tool for the comprehensive risk assessment for recurrence after early spinal instrumentation for pyogenic spondylodiscitis.

Clinical Characteristics of Patients with Pyogenic Vertebral Osteomyelitis and Concurrent Infections and Their Clinical Outcomes

Patients with pyogenic vertebral osteomyelitis (PVO) often develop concurrent infections, and a significant number of these patients show rapid deterioration in their medical condition, leading to mortality without PVO-related structural instability or neurological deficits. To improve clinical outcomes, we investigated the clinical presentation and treatment outcomes of patients with PVO and concurrent infections. This study included 695 patients with PVO, of which 175 (25%) had concurrent infections and 520 (75%) did not. The clinical characteristics of the two groups were compared, and multivariable analysis was performed to identify the association between concurrent infections and clinical outcomes. Patients with concurrent infections were older and had more comorbidities than those without. Moreover, there were significant intergroup differences in the anatomical involvement of PVO, and patients with concurrent infections had a higher number of regions involved more frequently than those without concurrent infections (15% vs. 6%). In contrast, patients with concurrent infections showed a lower degree of focal invasiveness, including a lower incidence of posterior abscess (47% vs. 59%; p = 0.008) and fewer neurological impairments according to the American Spinal Injury Association grade (p < 0.001) than those without concurrent infections. The causative organisms also differed significantly between the two groups, and patients with concurrent infections had a greater proportion of Gram-negative infections (31% vs. 16%, respectively) and a smaller proportion of methicillin-resistant S. aureus infections than those without concurrent infections (6% vs. 24%). Consequently, their clinical outcomes were significantly different, and patients with concurrent infections showed lower recurrence and higher mortality rates. We investigated the 1-year recurrence and mortality rates and their 95% confidence intervals according to the types of concurrent infections and their time of diagnosis and found variations in these parameters. Our results, based on a large number of patients, can be practically used as a reasonable reference to warn clinicians of the clinical risks of concurrent infections in patients with PVO and to help predict their clinical outcomes.

Common musculoskeletal disorders in chronic liver disease patients

Chronic liver disease (CLD) is the commonest ailment affecting the hepatobiliary system. Six significant pathologies related to CLD include hepatic osteodystrophy (HO), increased infection susceptibility, sarcopenia, osteonecrosis of the femoral head (OFH), increased risk of periprosthetic complications and fracture. Hepatic osteodystrophy, which comprises osteopenia, osteoporosis, and osteomalacia, refers to alterations in bone mineral metabolism found in patients with CLD. The HO prevalence ranges from 13 to 95%. Low complement levels, poor opsonization capacity, portosystemic shunting, decreased albumin levels, and impaired reticuloendothelial system make the cirrhotic patients more susceptible to developing infectious diseases. Septic arthritis, osteomyelitis, prosthetic joint infection, and cellulitis were common types of CLD-associated infectious conditions. The incidence of septic arthritis is 1.5 to 2-fold higher in patients with cirrhosis. Sarcopenia, also known as muscle wasting, is one of the frequently overlooked manifestations of CLD. Sarcopenia has been shown to be independent predictor of longer mechanical ventilation, hospital stay, and 12-month mortality of post-transplantation. Alcohol and steroid abuse commonly associated with CLD are the two most important contributory factors for non-traumatic osteonecrosis. However, many studies have identified cirrhosis alone to be an independent cause of atraumatic osteonecrosis. The risk of developing OFH in cirrhosis patients increases by 2.4 folds and the need for total hip arthroplasty increases by 10 folds. Liver disease has been associated with worse outcomes and higher costs after arthroplasty. Cirrhosis is a risk factor for arthroplasty complications and is associated with a prolonged hospital stay, higher costs, readmission rates, and increased mortality after arthroplasty. Greater physician awareness of risk factors associated with musculoskeletal complications of CLD patients would yield earlier interventions, lower healthcare costs, and better overall clinical outcomes for this group of patients.

Clinical Outcomes in Older Patients Aged over 75 Years Who Underwent Early Surgical Treatment for Pyogenic Vertebral Osteomyelitis

Older patients with pyogenic vertebral osteomyelitis (PVO) usually have more medical comorbidities compared with younger patients, and present with advanced infections from different causative organisms. To aid surgical decision-making, we compared surgical outcomes of older patients with PVO to those who underwent nonoperative treatment. We identified the risk factors for adverse post-operative outcomes, and analyzed the clinical risks from further spinal instrumentation. This retrospective comparative study included 439 patients aged ≥75 years with PVO. Multivariable analysis was performed to compare treatment outcomes among three groups: 194, 130, and 115 patients in the non-operative, non-instrumented, and instrumented groups, respectively. The risk factors for adverse outcomes after surgical treatment were evaluated using a logistic regression model, and the estimates of the multivariable models were internally validated using bootstrap samples. Recurrence and mortality of these patients were closely associated with neurologic deficits, and increased surgical invasiveness, resulting from additional spinal instrumentation, did not increase the risk of recurrence or mortality. We propose that surgical treatment for these patients should focus on improving neurologic deficits through immediate and sufficient removal of abscesses. Spinal instrumentation can be performed if indicated, within reasonable clinical risk.

Prediction of Recurrence in Pyogenic Vertebral Osteomyelitis by Artificial Neural Network Using Time-series Data of C-Reactive Protein: A Retrospective Cohort Study of 704 Patients

STUDY DESIGN

A retrospective cohort study.

OBJECTIVE

The aim of this study was to develop recurrence-prediction models of pyogenic vertebral osteomyelitis (PVO).

SUMMARY OF BACKGROUND DATA

Prediction of recurrence in PVO is crucial to avoid additional prolonged antibiotic therapy and aggressive spinal surgery and to reduce mortality. However, prediction of PVO recurrence by previously identified, initial risk factors is limited in PVO patients who exceptionally require prolonged antibiotic therapy and experience various clinical events during the treatment. We hypothesized that time-series analysis of sequential C-reactive protein (CRP) routinely measured to estimate the response to the antibiotics in PVO patients could reflect such long treatment process and increase the power of the recurrence-prediction model.

METHODS

A retrospective study was performed to develop a PVO recurrence-prediction model, including initial risk factors and time-series data of CRP. Of 704 PVO patients, 493 and 211 were divided into training and test cohorts, respectively. Conventional stepwise logistic regression and artificial neural network (ANN) models were created from the training cohort, and the predictions of recurrence in the test cohort were compared.

RESULTS

Prediction models using initial risk factors showed poor sensitivity (4.7%) in both conventional logistic model and ANN models. However, baseline ANN models using time-series CRP data showed remarkably increased sensitivity (55.8%-60.5%). Ensemble ANN model using both initial risk factors and time-series CRP data showed additional benefit in prediction power.

CONCLUSION

The recurrence-prediction models for PVO created only using the initial risk factors showed low sensitivity, regardless of statistical method. However, ANN models using time-series data of CRP values and their ensemble model showed considerably increased prediction power. Therefore, clinicians treating PVO patients should pay attention to the treatment response including changes of CRP levels to identify high-risk patients for recurrence, and further studies to develop recurrence-prediction model for PVO should focus on the treatment response rather than initial risk factors.Level of Evidence: 4.