Site-specific mortality in native joint septic arthritis: a national population study

Arthroscopy or arthrotomy for native knee septic arthritis: A systematic review

Purpose

Septic arthritis of any joint is an orthopaedic emergency which requires prompt diagnosis and treatment. The knee is the commonest joint afflicted, and the primary objective of any treatment is complete source control. This commonly takes the form of antibiotic therapy and a washout of the infected joint by means of arthroscopy or arthrotomy. The primary aim of this review is to investigate if arthroscopic washout for native knee septic arthritis confers a lower risk of repeat procedure than arthrotomy.

Methods

A systematic review and meta-analysis was conducted of the MEDLINE, SCOPUS and the Cochrane Library data bases. The primary outcome of interest was requirement for repeat washout with all-cause complications, length of inpatient stay and mortality secondary outcomes.

Results

A total of 17,140 subjects were included for analysis of the primary outcome, and the overall rate of repeat procedure was 14.6%. No statistical difference was found between arthroscopy and arthrotomy for repeat washout (risk ratio 0.86 [95% confidence interval, CI: 0.72-1.02], I 2 = 36%). Eligible studies found in favour of arthroscopy for all-cause complication rate (risk ratio 0.75 [95% CI: 0.6-0.93], I 2 = 84%) and length of stay in hospital (mean difference -1.98 days [95% CI: -3.43 to -0.53], I 2 = 84%). No statistical difference was found for the mortality rate (risk ratio 1.17 [95% CI: 0.52-2.63], I 2 = 57%).

Conclusion

Our analysis found arthroscopy and open arthrotomy to be equivocal for repeat surgical washout in native knee septic arthritis. All-cause complication rate and length of inpatient stay were favourable for arthroscopy with no difference noted between mortality rates.

Level of Evidence

Level III.

Advanced imaging shows extra-articular abscesses in two out of three adult patients with septic arthritis of the native hip joint

Background: Septic arthritis (SA) of the native adult hip is a rare orthopaedic emergency requiring prompt diagnosis and treatment. As clinical presentation and laboratory findings are frequently atypical, advanced imaging is often requested. This retrospective study aimed to investigate the prevalence and pattern of extra-articular infectious manifestations and their implications for pre-operative advanced imaging in patients with proven SA of the native hip joint. Methods: Out of 41 patients treated surgically for SA of the native hip during a 16-year period at our tertiary referral hospital, 25 received advanced imaging (computed tomography (CT), magnetic resonance imaging (MRI), or fluorodeoxyglucose positron emission tomography (FDG PET-CT)) prior to initial intervention. For each investigation, a specific set of variables was systematically interpreted, and the most suitable surgical approach was determined. The prognostic value was evaluated by comparing specific outcome measures and the extent of extra-articular involvement. Results: It was found that 32 % of patients had an abscess in one anatomical region, 32 % of patients had abscesses in multiple anatomical regions, and only 36 % of patients had no substantial abscess. Gluteal abscesses were especially common in patients with SA due to contiguous spread. Abscesses in the iliopsoas region were more common in patients with SA due to hematogenous seeding. A combination of several different surgical approaches was deemed necessary to adequately deal with the various presentations. No significant prognostic factors could be identified. Conclusion: We recommend performing advanced imaging in patients with suspected or proven septic arthritis of the native hip joint, as extra-articular abscesses are present in 64 % and might require varying anatomical approaches.

Administering Antibiotics for Less Than Four Weeks Increases the Risk of Relapse in Culture-Positive Septic Arthritis of Native Joints

(1) Objectives: This study investigated the optimal duration of antibiotic therapy and determined the risk factors associated with relapse in patients with culture-proven septic arthritis of native joints. (2) Methods: A retrospective review was conducted on patients aged ≥18 years diagnosed with native joint septic arthritis, with bacteria isolated from joints and/or blood. The exclusion criteria were prosthetic joint infections and cases with no identified microorganisms. The outcomes were assessed in the remission and relapse groups. (3) Results: Among 479 patients with native joint septic arthritis, 137 met the inclusion criteria, with a median follow-up duration of 2.7 years. The relapse rate was 9.5%, which mainly occurred within 30 days after antibiotic treatment completion. Compared with the remission group, the relapse group showed a significantly higher proportion of cases that received antibiotic therapy for ≤ 4 weeks (4.8% vs. 46.2%, p < 0.001), synovial fluid white blood cell (WBC) counts ≥150 × 103/mm3 (25.3% vs. 60.0%, p = 0.030), acute kidney injury (19.2% vs. 50%, p = 0.024), and extended-spectrum beta-lactamases-producing Enterobacteriaceae (0.8 vs. 15.4%, p = 0.024). Independent risk factors for relapse were determined as antibiotic therapy duration of ≤ 4 weeks (odds ratio (OR), 25.47; 95% confidence interval (CI), 1.57-412.33; p = 0.023) and synovial fluid WBC counts ≥150 × 103/mm3 (OR, 17.46; 95% CI, 1.74-175.62; p = 0.015). (4) Conclusions: Patients with native joint septic arthritis require vigilant monitoring for relapse, particularly when treated with antibiotic regimens administered for less than four weeks or when synovial aspirates exhibit elevated WBC counts at diagnosis.

Should treatment decisions in septic arthritis of the native hip joint be based on the route of infection?

Background: Surgical management of septic arthritis (SA) of the hip aims at treating the infection by either preserving, resecting or replacing the joint. In some cases, joint preservation should be attempted, whereas other cases would benefit from immediate joint resection or replacement. Prognostic factors have been proposed to guide decision-making. We hypothesized that most of these factors can be simplified to three subgroups based on the route of infection: contiguous spreading, direct inoculation or hematogenous seeding. Methods: A total of 41 patients have been treated surgically for SA of the native hip at our tertiary hospital during the last 16 years. Medical records were studied, and various patient and disease characteristics were collated. Results: Significant differences between (1) level of fitness, (2) condition of the hip joint, (3) micro-organisms and (4) chance of femoral head preservation were found for patients with SA of the native hip resulting from the three aforementioned subgroups. Femoral head resection was necessary at one point in 85 % of patients. Patients with hematogenous infections of undamaged hips had a reasonable chance (53 %) of avoiding joint resection or replacement. Hip arthroplasty was performed on 46.3 % of patients, with an infection rate of 10.5 %. Conclusion: Patients with SA of the native hip resulting from contiguous spreading, hematogenous seeding or direct inoculation differ significantly and should be considered distinct clinical entities. Route of infection is directly related to the chance of femoral head preservation and should, therefore, guide decision-making. Only patients with hematogenous infection to a previously healthy hip had the possibility of femoral head preservation.

Mid- to Long-Term Survival of Geriatric Patients with Primary Septic Arthritis of the Shoulder: A Retrospective Study over a Period of 20 Years

Septic arthritis of the shoulder is an urgent medical emergency that often occurs in elderly patients and is associated with high morbidity and mortality. Retrospectively, 56 patients aged ≥60 years, treated for primary septic monoarthritis of the shoulder at a maximum care hospital between 1 July 2001, and 30 July 2022, were included in this study. The primary aim of the study was analyzing survival rates and different bacteria in these patients. For statistical analysis, Kaplan-Meier curves were used for survival probability and the log-rank test was used to compare a survival probability of 5 years. The mean patient age was 78.7 years and a mean follow-up time of 3011.8 days. The mean survival of the entire study population was 920.3 days or 2.5 years. Significantly impaired 5-year survival was found only with increasing age and higher American Society of Anesthesiologists (ASA) physical status (PS) classification scores. Eight different types of bacteria were detected in the synovial fluid cultures. A total of 42 of 48 overall pathogens was Gram-positive and 6 were Gram-negative bacteria. Staphylococcus aureus was identified as the most frequent variant. We conclude that the mean survival is significantly shortened within the first 5 years with increasing age and ASA PS classification.

Early postoperative laboratory parameters are predictive of initial treatment failure in acute septic arthritis of the knee and shoulder joint

Septic arthritis is an orthopedic emergency potentially causing irreversible joint damage. However, the predictive value of potential risk factors such as early postoperative laboratory parameters remains uncertain. We investigated risk factors for initial surgical treatment failure using data from 249 patients (194 knees, 55 shoulders) treated for acute septic arthritis between 2003 and 2018. Necessity for further surgical intervention was defined as primary outcome. Demographic data, medical history, initial and postoperative laboratory parameters, Charlson Comorbidity Index (CCI), and Kellgren and Lawrence classification were collected. Two scoring systems were developed as tools for failure risk estimation after initial surgical irrigation and debridement. More than one intervention was necessary in 26.1% of cases. Treatment failure occurred significantly more often for those with longer symptom duration (p = 0.003), higher CCI grades (p = 0.027), Kellgren-Lawrence grade IV (p = 0.013), shoulder arthroscopy (p = 0.010), positive bacterial culture results (p < 0.001), slow postoperative CRP decline until day three (p = 0.032) and five (p = 0.015), reduced WBC-decline (p = 0.008), and lower hemoglobin (p < 0.001). Scores for third and fifth postoperative day achieved AUCs of 0.80 and 0.85, respectively. This study identified risk factors for treatment failure in patients with septic arthritis, suggesting that early postoperative laboratory parameters can guide further treatment.

Researchers in rheumatology should avoid categorization of continuous predictor variables

BACKGROUND

Rheumatology researchers often categorize continuous predictor variables. We aimed to show how this practice may alter results from observational studies in rheumatology.

METHODS

We conducted and compared the results of two analyses of the association between our predictor variable (percentage change in body mass index [BMI] from baseline to four years) and two outcome variable domains of structure and pain in knee and hip osteoarthritis. These two outcome variable domains covered 26 different outcomes for knee and hip combined. In the first analysis (categorical analysis), percentage change in BMI was categorized as ≥ 5% decrease in BMI, < 5% change in BMI, and ≥ 5% increase in BMI, while in the second analysis (continuous analysis), it was left as a continuous variable. In both analyses (categorical and continuous), we used generalized estimating equations with a logistic link function to investigate the association between the percentage change in BMI and the outcomes.

RESULTS

For eight of the 26 investigated outcomes (31%), the results from the categorical analyses were different from the results from the continuous analyses. These differences were of three types: 1) for six of these eight outcomes, while the continuous analyses revealed associations in both directions (i.e., a decrease in BMI had one effect, while an increase in BMI had the opposite effect), the categorical analyses showed associations only in one direction of BMI change, not both; 2) for another one of these eight outcomes, the categorical analyses suggested an association with change in BMI, while this association was not shown in the continuous analyses (this is potentially a false positive association); 3) for the last of the eight outcomes, the continuous analyses suggested an association of change in BMI, while this association was not shown in the categorical analyses (this is potentially a false negative association).

CONCLUSIONS

Categorization of continuous predictor variables alters the results of analyses and could lead to different conclusions; therefore, researchers in rheumatology should avoid it.

Multiple organ failure and death caused by Staphylococcus aureus hip infection: A case report

Suppurative arthritis has an acute onset and mostly affects old people and children. Recently, the incidence of adult suppurative hip arthritis, as well as its serious consequences, has increased. The deep hip joint and surrounding hypertrophic muscle tissue limit physical examination. Furthermore, they may cause variable and atypical symptoms of suppurative hip arthritis, possibly inducing delayed diagnosis and treatment. This atypical presentation is uncommon, causing delayed diagnosis and treatment, thus worsening the outcomes. We herein report the case of a 58-year-old man with Staphylococcus aureus (S. aureus) septicemia and multiple organ failure due to left pyogenic arthritis of the hip. The patient's early symptoms were extremely atypical given that he only presented hip pain. Moreover, there was no obvious history of trauma or inflammatory manifestations, such as fever or local swelling, and laboratory examination results and imaging findings were atypical. However, the disease progressed rapidly, developing into systemic sepsis within a short period of time followed by multiple organ failure and death. Early diagnosis and effective treatment of S. aureus hip arthritis are essential to avoid poor outcomes.

Mortality of septic knee arthritis in Korea: risk factors analysis of a large national database

This study aimed to analyze the risk factors for mortality of septic knee arthritis in Korea through a large nationwide data research. The National Health Insurance Service-Health Screening database was used to analyze 89,120 hospitalizations for septic knee arthritis between 2005 and 2018. In-hospital, thirty-day, and ninety-day mortality, and their association with patient’s demographic factors, various comorbidities (i.e., cerebrovascular disease, congestive heart failure, and myocardial infarction) and Charlson Comorbidity Index (CCI) were assessed. Secondary outcomes of complications (osteomyelitis, knee arthroplasty, recurrence) were analyzed. The number of hospitalization with septic knee arthritis increased from 1847 cases in 2005 to 8749 cases in 2018. There was no significant difference in mortality after diagnosis of septic knee arthritis between years. The risk of mortality in patients who hospitalized with septic knee arthritis increased in comorbidities like Congestive heart failure, dementia, myocardial infarction, chronic kidney disease. Hazard ratio (HR) decreased in patients who have comorbidities such as rheumatoid arthritis, liver disease, rheumatologic disease. HR for mortality in septic knee arthritis increased in patients with CCI more than 1. The risk factors for mortality in all periods were male sex, old age, high CCI, comorbidities such as congestive heart failure, dementia, myocardial infarction, chronic kidney disease. Efforts to reduce mortality should be concentrate more on patients with these risk factors.

Hospital care and medical costs of septic arthritis in Spain: a retrospective multicenter analysis

OBJECTIVES

This study aimed to review the characteristics of patients admitted with septic arthritis in Spanish hospitals and to measure the associated direct medical costs.

METHODS

Hospital admission records of patients with septic arthritis as a primary diagnosis registered between 2010 and 2019 were evaluated in a retrospective study. Admission cost in the database is based on the diagnosis-related group-based hospital payment systems, determined by the Spanish Ministry of Health.

RESULTS

Files from 16,438 patients were evaluated; median age was 56 years and 62.8% of patients were males. Staphylococcus was the most frequently registered pathogen, and 2.7% of admissions registered an antibiotic-resistant infection. Median hospitalization time was 14 days for adult patients and 8 days for children, with an in-hospital mortality rate of 3.7% for adult patients, and no deaths registered in children. The median length of intensive care unit (ICU) stay was 3 days. The mean admission cost was €6,382 per patient, with no significant differences between age groups. Admission costs increased significantly with the length of hospital stay. The total medical cost reached 12.7 million euros per year, considering all patients in the database.

CONCLUSIONS

This study provides new data on the medical costs of septic arthritis in Spain, providing a basis for the revision of resource allocation decisions in order to reduce the burden of this condition at the healthcare system level. Further research will be required to quantify the total burden associated with this condition.

Non-gonococcal septic arthritis of native joints in Western Australia. A longitudinal population-based study of frequency, risk factors and outcome

OBJECTIVE

To describe the incidence and long-term outcome of non-gonococcal septic arthritis (SA) in Western Australia (WA).

METHODS

Newman criteria were applied to define culture-positive SA and suspected SA cases in the state-wide West Australian Rheumatic Diseases Epidemiological Registry with longitudinally linked health data for patients >16 years with a first diagnostic code of pyogenic arthritis (711.xx [ICD-9-CM] and M00.xx [ICD-10-AM]) between 1990-2010. Annual incidence rates/100 000 (AIR) and standardized (against WA population) mortality rates/1000 person-years (SMR) and outcomes during 10.1 years follow-up are reported.

RESULTS

Among 2633 SA patients (68.6% male, age 47.4 years), 1146 (43.5%) had culture-positive SA. The overall AIR for culture-positive (1.6-6.3) and total SA cases (4.3-12.9) increased between 1990 and 2010 as did age at onset (39.5-54 years) and proportion of females (23-35.6%). Knees (33.6.%) were most frequently affected and 37.1% of cultures showed microorganisms other than Gram-positive cocci. Thirty-day rates for readmission and mortality were 25.4% and 3.2.%. During follow-up rates for serious infections (56.4%), osteoarthrosis (5.2%) and osteomyelitis (2.7%) were higher in culture-positive SA. SMR was increased for all SA patients but especially in those 17-40 years of age with culture-positive SA (24.2; 95% CI 2.3-261).

CONCLUSIONS

The incidence of SA in WA has risen steeply over 20 years. SA now occurs at higher age, affects females more often with over a third of cases caused by Gram-negative microorganisms. Not only culture-positive, but also suspected SA led to increased bone/joint complications, in-hospital and late mortality.

Native joint infections in Iceland 2003-2017: an increase in postarthroscopic infections

Objectives

Nationwide study on the epidemiology, clinical characteristics and outcomes among patients with native joint infection (NJI) in Iceland, 2003–2017.

Methods

All positive synovial fluid culture results in Iceland were identified and medical records reviewed.

Results

A total of 299 NJI (40 children and 259 adults) were diagnosed in Iceland in 2003–2017, with a stable incidence of 6.3 cases/100 000/year, but marked gender difference among adults (33% women vs 67% men, p<0.001). The knee joint was most commonly affected, and Staphylococcus aureus was the most common isolate in both adults and children, followed by various streptococcal species in adults and Kingella kingae in children. NJI was iatrogenic in 34% of adults (88/259) but comprised 45% among 18–65 years and a stable incidence. Incidence of infections following arthroscopic procedures in adults increased significantly compared with the previous decade (9/100 000/year in 1990–2002 vs 25/100 000/year in 2003–2017, p<0.01) with no significant increase seen in risk per procedure. The proportion of postarthroscopic NJI was 0.17% overall but 0.24% for knee arthroscopy. Patients with postarthroscopic infection were more likely to undergo subsequent arthroplasty when compared with other patients with NJI (p=0.008).

Conclusions

The incidence of NJI in Iceland has remained stable. The proportion of iatrogenic infections is high, especially among young adults, with an increase seen in postarthroscopic infections when compared with the previous decade. Although rare, NJI following arthroscopy can be a devastating complication, with significant morbidity and these results, therefore, emphasise the need for firm indications when arthroscopic treatment is considered.

Association of childhood physical and sexual abuse with arthritis in adulthood: Findings from a population-based study

The objective of this cross-sectional study was to investigate childhood physical and sexual abuse as factors associated with arthritis among adults from selected states in the United States. Data for this study came from the 2019 Behavioral Risk Factor Surveillance System survey. An analytic sample of 75,717 adults 18-75 years old (49.7% female) was analyzed using log-binomial regression. The outcome variable investigated in this study was arthritis, and the main explanatory variables were childhood physical and sexual abuse. Of the 75,717 respondents examined, 20,938 (representing 27.6%) had arthritis. A little over one in four respondents (25.5%) experienced childhood physical abuse and 5.6% experienced childhood sexual abuse by age 18. In the multivariable regression, respondents who experienced childhood physical abuse had 1.36 times the risk of having arthritis when compared to respondents who did not experience childhood physical abuse (ARR = 1.36, p < .001, 95% CI = 1.28-1.46). Respondents who experienced childhood sexual abuse had 1.60 times the risk of having arthritis when compared to respondents who did not experience childhood sexual abuse (ARR = 1.74, p < .001, 95% CI = 1.54-1.97). The findings of this study demonstrate that childhood physical and sexual abuse are associated with arthritis later in adulthood. The associations persisted even after adjusting for demographic, socioeconomic status, body mass index (BMI), current smoking status, and self-perceived physical health. The findings of this study add to the burgeoning number of studies demonstrating the adverse impact of childhood physical and sexual abuse on chronic health outcomes among adults.