Native Joint Septic Arthritis: Epidemiology, Clinical Features, and Microbiological Causes in a New Zealand Population

Native and prosthetic septic arthritis in a university hospital in Saudi Arabia: A retrospective study

BACKGROUND

Septic arthritis, whether native or prosthetic, poses a significant challenge in clinical practice due to its potentially devastating consequences. Despite its clinical importance, there remains a dearth of comprehensive studies and standardized diagnostic criteria, particularly in the Kingdom of Saudi Arabia.

AIM

To investigate the epidemiology, microbiological profiles, and clinical characteristics of native and prosthetic septic joints in the Saudi Arabian population.

METHODS

Medical records of patients diagnosed with septic arthritis between January 1, 2015, and December 31, 2022, were retrospectively reviewed. Data regarding patient demographics, clinical presentation, microbiological cultures, treatment modalities, and outcomes were analyzed.

RESULTS

In a retrospective review of 52 cases of septic arthritis, a balanced gender distribution was observed (1:1 ratio), with the knee being the most commonly affected joint (80.8%). Methicillin-resistant Staphylococcus aureus predominated in native joints (24.2%), while Brucella spp. was more prevalent in prosthetic joints (21.1%). Joint preservation was achieved in most cases (84.6%), with no significant difference in clinical features between native and prosthetic joints. However, certain comorbidities were more common in native joint cases, including renal impairment (P = 0.002), hemodialysis (P = 0.004), heart disease (P = 0.013), and chronic liver disease (P = 0.048). At the same time, osteoarthritis was more prevalent in prosthetic joint cases (P = 0.013). Vancomycin was the most frequently used antibiotic (26.9%), and most patients received antibiotics before joint aspiration (57.7%). Surgical intervention, predominantly arthrotomy, was required in most cases (32.7%). Notably, a significant association was found between joint type and mortality (odds ratio = 0.587, P = 0.048), as well as the Charlson comorbidity index and mortality (P = 0.001).

CONCLUSION

This study highlighted distinctive microbiological profiles and etiological factors in septic arthritis cases in the Saudi Arabian population.

Septic arthritis of the facet joint is also a severe vertebral infection: A multicenter retrospective study of 65 patients

OBJECTIVE

Septic arthritis of the Facet Joints (SAFJ) is a rare condition. Little data has been published on the subject. We aimed to describe the clinical, biological and imagery presentations, as well as the course of this rare infection.

METHODS

We included patients hospitalized between January 1st, 2016 and December 31th, 2019, in the Departments of Infectious Diseases or Rheumatology in 5 French centres in the CRIOGO network. We defined septic arthritis according to Newman's criteria and facet joint arthritis using imagery.

RESULTS

Sixty-five patients were included, predominantly males (64.6%), with a mean age of 68.1 years. The mean time to diagnosis was 25.0 days. The principal symptoms at diagnosis were acute back pain (95.2%) and fever (76.9%). Neurological symptoms were present for 60.7% of the patients, including 16.4% motor deficit or cauda equina syndrome. SAFJ was located on the lumbosacral spine (73.4%) and was rarely multifocal (4.7%). Bacteriological identification was performed by blood cultures in 84.4% of the cases, and the pathogen was mainly Staphylococcus aureus (49.2%). Infective endocarditis was present for 26.9% of patients assessed by echocardiography. On MRI, soft tissue abscess or inflammation, epiduritis and epidural abscess were present in 87.1%, 66.7% and 33.9% of cases, and the pathogen was significantly more frequently Staphylococcus aureus. Mortality reached 9.2%, 18.5% and 23% at one, two, and three years respectively.

CONCLUSION

SAFJ is a rare but severe disease. Microbiological diagnosis is primarily made on blood cultures, and S. Aureus was the main pathogen. Our results highlight the fact that SAFJ is associated with high morbidity and mortality, and with infective endocarditis.

Septic arthritis of the native hip joint and septic pulmonary embolism in an adult with sickle cell trait after a complicated dental extraction

Septic arthritis (SA) is a serious infection of the joint which can lead to irreversible destruction of the joint.We report a case of right hip SA with septic pulmonary embolism following a complicated dental extraction in a woman in her early 40s with sickle cell trait (SCT).The patient presented with severe right thigh pain and left jaw pain.Initial workup revealed raised C reactive protein and positive blood cultures. Right hip joint SA was confirmed following intraoperative joint aspiration. The patient had right hip debridement with long-term intravenous antibiotics.The incidence of SA in adults with sickle cell disease is low: 0.3% in a study in France and Brazil and 10.3% incidence of haematogenous osteoarticular infection in children with SCT in West Africa.

The Septic Elbow Joint: Treatment Approaches for Improved Patient Outcomes

Septic arthritis of the elbow is a serious problem requiring prompt, accurate diagnosis and urgent surgical intervention. Achieving successful patient outcomes depends heavily on early diagnosis and efficient streamlined surgical treatment. Essential tactics for treating the septic elbow joint include immediate joint irrigation and debridement in addition to administration of appropriate antibiotics. This comprehensive review delves into the cause of the septic elbow joint, identifies associated risk factors, and provides a comprehensive approach encompassing the diagnosis and treatment of the septic elbow. The aim of this review is to optimize patient care and outcomes.

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.

Upper extremity infection: imaging features with focus on magnetic resonance imaging

Upper extremity infections are frequently seen, especially in individuals with weakened immune system, posttraumatic events, and after surgery procedures. If not properly treated, such conditions can lead to serious consequences, such as movement impairment, amputation, and even mortality. These infections have the potential to spread extensively from their initial site of entry, traversing interconnected spaces either intra or extra-compartmental. Understanding the relevant anatomy is crucial to assess location and stage of infection, since surgical intervention and intravenous antibiotics are usually required. In this article, the authors provide a comprehensive review of the imaging findings of upper extremity infection, focusing on magnetic resonance imaging (MRI). Furthermore, this article sheds light on the pivotal role of radiology in managing hand, elbow, and shoulder infections offering an overview of available treatment options. KEY FINDINGS: Various types of infections affecting the upper extremity will be discussed, including infectious tenosynovitis, deep space infections, septic arthritis, and osteomyelitis. Authors also highlight anatomical spaces, common pathogens, spread routes, and key radiological features of these conditions.

Methicillin Resistance Increased the Risk of Treatment Failure in Native Joint Septic Arthritis Caused by Staphylococcus aureus

This study aimed to compare clinical characteristics and outcomes in patients with native joint septic arthritis (NJSA) due to methicillin-resistant Staphylococcus aureus (MRSA) in comparison to methicillin-sensitive S. aureus (MSSA) and identify treatment failure risk factors. We conducted a multi-center retrospective study on adult NJSA patients at three teaching hospitals in South Korea from 2005 to 2017. Among 101 patients diagnosed with S. aureus NJSA, 39 (38.6%) had MRSA strains. Compared to MSSA, patients with MRSA had a higher prevalence of nosocomial infections (17.9% vs. 1.6%; p = 0.005) and received inappropriate antibiotics within 48 h more frequently (74.4% vs. 0%; p < 0.001). In total, twenty patients (19.8%) experienced treatment failure, which encompassed five patients (5.0%) who passed away, nine (8.9%) requiring repeated surgical drainage after 30 days of antibiotic therapy, and seven (6.9%) with relapse. The MRSA group showed a higher rate of overall treatment failure (33.3% vs. 11.3%; p = 0.007) with a notably increased frequency of requiring repeated surgical interventions after 30 days of antibiotic therapy (17.9% vs. 3.2%, p = 0.026), in contrast to the MSSA group. Independent risk factors for treatment failure included Charlson comorbidity score, elevated CRP levels, and methicillin resistance. Methicillin resistance is an independent risk factor for treatment failure, emphasizing the need for vigilant monitoring and targeted interventions in MRSA-related NJSA cases.

Incidence and Prevalence of Septic Arthritis in Thailand: A Database from the Ministry of Public Health

Background

A better understanding of the epidemiological profile of septic arthritis or pyogenic arthritis in Thais could improve care and provide information for better infectious control. We aimed to determine the incidence and prevalence of septic arthritis in Thailand between 2017 and 2020.

Methods

A descriptive epidemiological study was performed using demographic data from patients over 18 years of age having a primary diagnosis of M00 pyogenic arthritis between 2017 and 2020. Data were sourced from the Information and Communication Technology Center, Ministry of Public Health database. The incidence and prevalence of septic arthritis were calculated, and their respective 95% confidence interval (CI).

Results

The number of patients with septic arthritis in 2017 was 26,878 from a total Thai population of 65,204,797. The prevalence of septic arthritis in 2017 was 41.2 per 100,000 (95% CI 40.7-41.7). The prevalence of septic arthritis among women was slightly higher than among men (42.2 vs 40.2 per 100,000). The incidence of septic arthritis slightly increased from 2018 to 2019 but was stable in 2020 (22.6, 23.3, and 23.1 per 100,000 person-years, respectively). The incidence was highest in the southern region between 2018 and 2019 but highest in the northeast in 2020. The peak was in the elderly population 60 and older (56.4, 59.5, and 57.3 per 100,000 person-years in 2018, 2019, and 2020, respectively). The incidence increased with age and the maximum rate was in those ≥ 70 years (70.2 per 100,000 person-years in 2019).

Conclusion

Septic arthritis commonly presents in the elderly and is comparable between men and women. The disease was found mainly in the northeastern and southern regions. The incidence remained stable during the study period.

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.

An update on recent progress of the epidemiology, etiology, diagnosis, and treatment of acute septic arthritis: a review

Acute septic arthritis is on the rise among all patients. Acute septic arthritis must be extensively assessed, identified, and treated to prevent fatal consequences. Antimicrobial therapy administered intravenously has long been considered the gold standard for treating acute osteoarticular infections. According to clinical research, parenteral antibiotics for a few days, followed by oral antibiotics, are safe and effective for treating infections without complications. This article focuses on bringing physicians up-to-date on the most recent findings and discussions about the epidemiology, etiology, diagnosis, and treatment of acute septic arthritis. In recent years, the emergence of antibiotic-resistant, particularly aggressive bacterial species has highlighted the need for more research to enhance treatment approaches and develop innovative diagnosis methods and drugs that might combat better in all patients. This article aims to furnish radiologists, orthopaedic surgeons, and other medical practitioners with contemporary insights on the subject matter and foster collaborative efforts to improve patient outcomes. This review represents the initial comprehensive update encompassing patients across all age groups.

Bilateral Knee Septic Arthritis in a Seven-Month-Old Girl

Septic arthritis (SA) is a type of joint inflammation caused by an infection. It is an orthopedic emergency that requires immediate treatment to avoid serious complications such as joint destruction, osteomyelitis, and sepsis. We present a case of bilateral knee SA in a seven-month-old female who presented to our emergency department with left knee SA, followed by right knee SA one month later.

SPILF update on bacterial arthritis in adults and children

In 2020 the French Society of Rhumatology (SFR) published an update of the 1990 recommendations for management of bacterial arthritis in adults. While we (French ID Society, SPILF) totally endorse this update, we wished to provide further information about specific antibiotic treatments. The present update focuses on antibiotics with good distribution in bone and joint. It is important to monitor their dosage, which should be maximized according to PK/PD parameters. Dosages proposed in this update are high, with the optimized mode of administration for intravenous betalactams (continuous or intermittent infusion). We give tools for the best dosage adaptation to conditions such as obesity or renal insufficiency. In case of enterobacter infection, with an antibiogram result "susceptible for high dosage", we recommend the requesting of specialized advice from an ID physician. More often than not, it is possible to prescribe antibiotics via the oral route as soon as blood cultures are sterile and clinical have symptoms shown improvement. Duration of antibiotic treatment is 6 weeks for Staphylococcus aureus, and 4 weeks for the other bacteria (except for Neisseria: 7 days).

Atypical Staphylococcal Septic Arthritis in a Native Hip: A Case Report and Review

Septic arthritis is a synovial fluid and joint tissue infection with significant morbidity and mortality risk if not diagnosed and treated promptly. The most common pathogen to cause septic arthritis is Staphylococcus aureus, a Gram-positive bacterium. Although diagnostic criteria are in place to guide the diagnosis of staphylococcal septic arthritis, there is a lack of adequate sensitivity and specificity. Some patients present with atypical findings which make it difficult to diagnose and treat in time. In this paper, we present the case of a patient with an atypical presentation of recalcitrant staphylococcal septic arthritis in a native hip complicated by uncontrolled diabetes mellitus and tobacco usage. We review current literature on diagnosing S. aureus septic arthritis, novel diagnostic technique performance to guide future research and assist clinical suspicion, and current S. aureus vaccine development for at-risk patients.

Septic arthritis of the native hip joint: a multi-pattern, multi-outcome disease

PURPOSE

Septic arthritis of the native hip joint (SANH) is an uncommon surgical and medical emergency with few reports. The aim of this study was to determine predictors of return to theatre (RTT), complications and mortality.

METHODS

Patients with SANH were identified from January 2009 to June 2022; 50 patients and three subgroups were identified: Pyogenic (surgical washout without systemic inflammatory disease), Systemic (surgical washout with SIDs) and patients managed non-surgically. Patterns of these groups were assessed with a principal component analysis. The cumulative incidences for death, any complication and RTT for repeat washout were calculated. The predictive variables associated with outcomes were selected with univariable models and then incorporated in multivariable CoxPH regressions.

RESULTS

The 1-year cumulative incidence was 14% for mortality and 48.5% for any complication. Amongst patients managed surgically, 1-year risk of RTT was 46% in Pyogenic subgroup and 21% in Systemic subgroup. Systemic subgroup had lower complications and RTT and higher rate of sterile aspirate, compared to Pyogenic. Charlson comorbidity index (CCI) (HR = 1.41, P value = 0.03), preoperative albumin (HR = 0.81, P value = 0.009) and preoperative haemoglobin (HR = 0.95, P value = 0.02) were significantly associated with 1-year mortality. Time between symptom onset and admission > 7 days (HR = 3.15, P value = 0.042), preoperative Hb (HR = 1.05, P value = 0.016), socioeconomic deprivation (HR = 1.18, P value = 0.04) and Systemic subgroup (HR = 0.25, P value = 0.04) were significantly associated with RTT.

CONCLUSION

Mortality was well predicted by the usual parameters including CCI, albumin, but also low haemoglobin. Patients presenting in a delayed fashion were more likely to have multiple lavages.

A case of septic arthritis of the elbow joint in rheumatoid arthritis diagnosed by arthroscopic synovectomy

We report a case of methicillin-resistant Staphylococcus aureus (MRSA) septic arthritis of the elbow detected by arthroscopic synovectomy in an 81-year-old woman with rheumatoid arthritis (RA) who was initially diagnosed with a rheumatoid arthritis flare-up. The patient was administered abatacept, an antirheumatic biological agent, as the synovial fluid culture was negative. Destruction of the joint progressed despite medication, and the patient underwent arthroscopic synovectomy. MRSA was detected in the culture of the synovium that was collected intraoperatively, and septic arthritis was diagnosed. The infection subsided with anti-MRSA antibiotics, but the patient continued to experience moderate pain and limited motion. In RA patients, it might be difficult to differentiate minor findings from infection. Arthroscopic synovectomy is one of the selectable procedures that should be actively considered when infection is suspected.

Performance of a diagnostic score for gouty arthritis: results from a cohort of acute arthritis suspected of being septic

Septic arthritis (SA) and gout are the main suspected etiologies of acute monoarthritis. Differentiating them is essential because SA is an emergency. The performance of a gout diagnostic score developed by Janssens et al. was investigated in a cohort of patients with acute arthritis suspected of being septic. This was an ancillary study of a single-center cohort of patients with suspected SA. Patients were classified into three groups according to the final diagnosis (gout, SA or other diagnosis). We assessed the performance of the score (sensitivity [Se], specificity [Sp], positive and negative predictive value [PPV, NPV], area under the receiver operating characteristic [ROC] curve) for the diagnosis of gouty arthritis. In total, 138 patients were included: 28 (20.3%) had gout, 42 (30.4%) SA, and 68 (49.3%) another diagnosis. The median diagnostic score was 7.0 [4.5; 8.8] for patients with gout, 3.5 [2.5; 6.0] for those with SA and 3.0 [2.0-5.0] for those with another diagnosis. With a score threshold of ≥ 8, the Se for a diagnosis of gout was 28.6%, Sp 96.4%, PPV 66.7%, and NPV 84.1%. With a threshold of ≤ 4, the Se was 82.1%, Sp 64.5%, PPV 37.1%, and NPV 93.4%. The area under the ROC for the diagnostic score was 0.79. The performance of the clinico-biological score of Janssens et al. for a diagnosis of gout applied to a cohort of patients with acute arthritis and suspected of being septic was poor. Joint aspiration remains necessary to differentiate SA from another etiology.

Reduced Costs, Complications, and Length of Stay After Arthroscopic Versus Open Irrigation and Débridement for Knee Septic Arthritis

BACKGROUND

In the treatment of native knee bacterial septic arthritis, the optimal irrigation and débridement modality-arthroscopic versus open-is a matter of controversy. We aim to compare revision-free survival, complications, and resource utilization between these approaches.

METHODS

The National Readmission Database was queried from 2016 to 2019 to identify patients using International Classification of Diseases, 10th revision, diagnostic and procedure codes. Days to revision irrigation and débridement (I&D), if any, were calculated for patients during index admission or subsequent readmissions. Multivariate regression was used for healthcare utilization analysis. Survival analysis was done using Kaplan-Meier analysis and Cox proportional hazard regression.

RESULTS

A total of 14,365 patients with native knee septic arthritis undergoing I&D were identified, 8,063 arthroscopic (56.1%) and 6,302 open (43.9%). The mean follow-up was 148 days (interquartile range 53 to 259). A total of 2,156 patients (15.0%) underwent revision I&D. On multivariate analysis, arthroscopic I&D was associated with a reduction in hospital costs of $5,674 and length of stay of 1.46 days (P < 0.001 for both). Arthroscopic I&D was associated with lower overall complications (odds ratio [OR] 0.63, P < 0.001), need for blood transfusion (OR 0.58, P < 0.001), and wound complications (OR 0.32, P < 0.001). Revision-free survival after index I&D was 95.3% at 3 days, 91.0% at 10 days, 88.3% at 30 days, 86.0% at 90 days, and 84.5% at 180 days. No statistically significant difference was observed between surgical approaches on Cox modeling.

DISCUSSION

Risk of revision I&D did not differ between arthroscopic and open I&D; however, arthroscopy was associated with decreased costs, length of stay, and complications. Additional study is necessary to confirm these findings and characterize which patients require an open I&D.

LEVEL OF EVIDENCE

III.

Lower Risk of Revision Surgery After Arthroscopic Versus Open Irrigation and Débridement for Shoulder Septic Arthritis

BACKGROUND

In the treatment of native shoulder septic arthritis, the optimal irrigation and débridement modality-arthroscopic versus open-is a matter of controversy. We aim to compare revision-free survival (RFS), complications, and resource utilization between these approaches.

METHODS

The National Readmission Database was queried from 2016 to 2019 to identify patients using International Classification of Diseases, 10th revision, diagnostic and procedure codes. Days to revision irrigation and débridement (I&D) were calculated for patients during index admission or subsequent readmissions. Multivariate regression was used for healthcare utilization analysis. Survival analysis was done using Kaplan-Meier analysis and Cox proportional hazard regression.

RESULTS

A total of 4,113 patients with native shoulder septic arthritis undergoing I&D were identified, 2,775 arthroscopic (67.5%) and 1,338 open (32.5%). The median follow-up was 170 days (interquartile range 79 to 265). A total of 341 patients (8.3%) underwent revision I&D at a median of 9 days. On multivariate analysis, arthroscopic I&D was associated with a reduction in hospital costs of $4,154 ( P < 0.001) and length of stay of 0.78 days ( P = 0.030). Arthroscopic I&D was associated with reduced blood transfusions (odds ratio 0.69, P = 0.001) and wound complications (odds ratio 0.30, P < 0.001). RFS was 96.4%, 94.9%, 93.3%, and 92.6% for arthroscopic I&D and 94.1%, 92.6%, 90.4%, and 89.0% for open I&D at 10, 30, 90 and 180 days, respectively ( P = 0.00043). On multivariate Cox modeling, arthroscopic I&D was associated with improved survival (hazard ratio 0.67, P = 0.00035). On stratified analysis, arthroscopic I&D was associated with improved RFS in patients aged 65 years or older ( P < 0.001), but RFS was similar in those younger than 65 years ( P = 0.17).

CONCLUSION

Risk of revision I&D was markedly lower after arthroscopic I&D compared with open, although the protective benefit was limited to patients aged 65 years or older. Arthroscopy was also associated with decreased costs, length of stay, and complications. Although surgeons must consider specific patient factors, our results suggest that arthroscopic I&D is superior to open I&D.

LEVEL OF EVIDENCE

III.

Short-term outcomes of two-stage reverse total shoulder arthroplasty with antibiotic-loaded cement spacer for shoulder infection

Background

The purpose of our study was to investigate short-term outcomes of two-stage reverse total shoulder arthroplasty (RTSA) with an antibiotic-loaded cement spacer for shoulder infection.

Methods

Eleven patients with shoulder infection were treated by two-stage RTSA following temporary antibiotic-loaded cement spacer. Of the 11 shoulders, nine had pyogenic arthritis combined with complex conditions such as recurrent infection, extensive osteomyelitis, osteoarthritis, or massive rotator cuff tear and two had periprosthetic joint infection (PJI). The mean follow-up period was 29.9 months (range, 12–48 months) after RTSA. Clinical and radiographic outcomes were evaluated using the visual analog scale (VAS) score for pain, American Shoulder and Elbow Surgeons (ASES) score, subjective shoulder value (SSV), and serial plain radiographs.

Results

The mean time from antibiotic-loaded cement spacer to RTSA was 9.2 months (range, 1–35 months). All patients had no clinical and radiographic signs of recurrent infection at final follow-up. The mean final VAS score, ASES score, and SSV were significantly improved from 4.5, 38.6, and 29.1% before RTSA to 1.7, 75.1, and 75.9% at final follow-up, respectively. The mean forward flexion, abduction, external rotation, and internal rotation were improved from 50.0°, 50.9°, 17.7°, and sacrum level before RTSA to 127.3°, 110.0°, 51.8°, and L2 level at final follow-up, respectively.

Conclusions

Two-stage RTSA with antibiotic-loaded cement spacer yields satisfactory short-term clinical and radiographic outcomes. In patients with pyogenic arthritis combined with complex conditions or PJI, two-stage RTSA with an antibiotic-loaded cement spacer would be a successful approach to eradicate infection and to improve function with pain relief.

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.

Septic arthritis of the hand: Current issues of etiology, pathogenesis, diagnosis, treatment

Septic arthritis of the hand is a serious disease that often results in dysfunction of the joint or even the need to perform amputation of the finger. They rank second in the frequency of occurrence after lesions of the knee joint. Many points concerning the etiology, the timing of the development of cartilage destruction and the development of osteomyelitis, approaches to surgical treatment, the duration of antibiotic therapy, and the start of rehabilitation measures remain the subject of numerous discussions. Based on a search in the PubMed, Web of Science and Google Scholar databases down to 1990-2021, publications on septic arthritis of the hand were found and analyzed. The following inclusion criteria were used in our review: (1) Septic arthritis of the hand; (2) Published in a peer review journal; (3) Written in English; and (4) Full text version available. Studies were excluded if they met any of the following criteria: (1) Letters; (2) Articles published in abstract form only; and (3) Cadaveric studies. Septic arthritis of the hand was characterized by the most frequent damage to the joints of the index and middle fingers (> 50% of cases). Up to 90% of cases, the infection enters the joint as a result of penetrating trauma, animal bites, etc. Staphylococcus aureus became the most frequently isolated microorganism (30%-55%), and its polyantibiotic-resistant form Methicillin-resistant Staphylococcus aureus was found, according to various sources, from 0% to 73% among all isolated Staphylococcus aureus. In arthritis, Pasteurella multocida (6%-11%) is often isolated as a result of animal bites. Articular cartilage destruction in the experiment developed within 24-48 h after infection. In clinical studies, the development of osteomyelitis was noted when treatment was delayed by more than 10 d. X-ray data during the first two weeks were uninformative. Priority of surgical treatment of septic arthritis. Drainage and surgical treatment, and with the development of osteomyelitis, the implementation of arthrodesis. Antibacterial therapy for 2-4 wk and early start of rehabilitation measures. Timely surgical treatment in combination with antibiotic therapy and rehabilitation makes it possible to obtain a positive result in the treatment of septic arthritis of the hand.

Management and outcome of native joint septic arthritis: a nationwide survey in French rheumatology departments, 2016-2017

OBJECTIVES

To describe current management and outcome of native joint septic arthritis (NJSA) in French rheumatology departments.

METHODS

For this retrospective, nationwide multicentric study, 127 French rheumatology departments were contacted to report up to 12 cases of NJSA that occurred between 1 January 2016 and 31 December 2017. Characteristics, diagnosis procedures, therapeutic management and outcome were recorded.

RESULTS

Overall, 362 patients were included (mean age 64.0±18.6 years, median Charlson comorbidity index 3.5 (0-14)). Knee was the most frequent site (n=160 (38.9%)), and Staphylococcus sp (n=185 (51.4%)), the most frequent pathogen. All patients received antibiotics for a mean duration of 46.8 (±22.0) days, including intravenous route for a mean of 17.2 (±15.4) days. Management was heterogeneous. Surgical procedure was performed in 171 (48.3%), joint immobilisation in 128 (43.8%). During follow-up, 91 (28.3%) patients have had serious complications and 28 (9.2%) of them died. Factors associated with 1-year mortality were age (OR 1.08, 95% CI 1.04 to 1.13; p<0.001), Charlson's index (OR 1.30, 95% CI 1.06 to 1.58; p=0.012), presence of bacteraemia (OR 4.02, 95% CI 1.35 to 11.99; p=0.008), antibiotic use in the previous 3 months (OR 3.32, 95% CI 1.11 to 9.87; p=0.029) and Staphylococcus aureus NJSA compared with Streptococcus sp. NJSA (OR 7.24, 95% CI 1.26 to 41.68, p=0.027). The complete recovery with no adverse joint outcome at 1 year was observed in n=125/278 patients (55.0%).

CONCLUSION

Prognosis of NJSA remained severe with a high rate of morbimortality. Its management was very heterogeneous. This study highlights the importance of the new French recommendations, published after the completion of the study, in order to facilitate NJSA management.

Factors affecting the occurrence of osseous lesions in septic shoulder arthritis and the recurrence rate after arthroscopic surgery

HYPOTHESIS

The purpose of this study was to determine the incidence of osseous lesions and the recurrence rate after arthroscopic surgery in shoulder septic arthritis patients and evaluate the influencing factors.

MATERIALS AND METHODS

We retrospectively reviewed 44 patients who underwent arthroscopic surgery for septic arthritis of the shoulder between January 2012 and September 2019. The average age of the patients was 65.57 ± 14.2 years, and 56.8% were female patients. The minimum follow-up period was 12 months (average, 32.8 ± 14.2 months; range, 12-72 months). We assessed variables including sex, age, underlying diseases, duration from symptom onset to magnetic resonance imaging (MRI), duration from symptom onset to surgery, radiologic results (radiography and MRI), history of injection therapy, and postoperative infection. The incidence of osseous lesions and the recurrence rate were calculated according to independent variables. In addition, multivariate logistic regression was performed to identify the risk factors for osseous lesions and recurrent infection after adjustment for other variables.

RESULTS

Twenty-one patients had an osseous lesion on MRI, and 12 patients had evidence of bone erosion on radiographs. In univariate analyses, significant (P < .05) risk factors for the presence of osseous lesions were female sex, lower C-reactive protein level, and longer duration from symptom onset to MRI. The overall infection recurrence rate was 22.7% (10 of 44 patients). Culture results and the duration from symptom onset to surgery were significant risk factors for recurrent infection (P < .05). As the duration from symptom onset to MRI increased by 1 day, the probability of osseous lesions increased 1.31-fold (95% confidence interval, 1.08- to 1.59-fold; P = .007), and this probability was significantly higher after correction for other risk factors.

CONCLUSIONS

To reduce the severity of septic shoulder infection, timely diagnosis and treatment are essential. Even if osseous lesions are present, good results can be obtained if meticulous débridement is performed through arthroscopic surgery. However, functional and radiologic long-term follow-up studies are needed in patients with osseous lesions.

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.

A Case of Native Joint Septic Arthritis Caused by Bacteroides fragilis

Patient: Male, 65-year-old

Final Diagnosis: Sepsis

Symptoms: Knee pain

Medication:—

Clinical Procedure: Arthrocentesis

Specialty: Infectious Diseases

[Management of joint empyema]

Joint empyema, also known as septic arthritis, is a severe disease associated with considerable morbidity and mortality. Failing to initiate immediate treatment can result in irreversible joint destruction within a short time. The knee joint is most frequently involved, followed by the shoulder and hip joints. Small joints are rarely affected. Typical risk factors include immunosuppression, renal insufficiency, diabetes mellitus and previous joint interventions. An early targeted diagnostic work-up and initiation of therapeutic steps is crucial to avoid irreversible joint destruction. Joint aspiration for diagnostic purposes is essential and should be performed immediately when a septic arthritis is suspected. An important differential diagnosis is metabolic arthritis (gout and chondrocalcinosis), which typically presents in a similar way. A differentiation from septic arthritis is important as metabolic arthritis requires a completely different treatment. After confirming the diagnosis, treatment consisting of a surgical procedure combined with antibiotics is initiated. In most cases an arthroscopic intervention is sufficient. In severe cases the arthroscopy needs to be repeated. An arthrotomy must be carried out only rarely. A pre-emptive antibiotic treatment is initially administered and is later adjusted according to the resistogram. This article gives an overview on the pathophysiology, diagnostics and general management of joint empyema.

The profile of the causative organisms which lead to septic arthritis of native joints over the last two decades in a single tertiary medical center in the east coast of the United States

BACKGROUND

Septic arthritis (SA) is associated with significant morbidity and mortality. Delayed or inadequate treatment may result in joint destruction, osteomyelitis and sepsis. Like other types of infection, the causative agents of SA may have changed over time. Early targeted intervention is important in cases of SA and can be achieved only by understanding the current trends in the microbiology of SA.

OBJECTIVES

To determine the trends in the microbiology of SA over the last two decades.

METHODS

We conducted a retrospective study including all patients 18 and older with culture positive, surgically treated, native joint septic arthritis (NJSA), admitted to a single tertiary medical centre in Boston between the years of 1997 and 2015. We excluded cases of osteomyelitis and septic bursitis. We focused our analysis on the microbiology data which included synovial fluid gram stain and culture, blood cultures and synovial biopsy cultures.

RESULTS

Among 260 cases, the most common bacteria isolated were Methicillin Sensitive Staphylococcus aureus (MSSA, 36%), Methicillin Resistant Staphylococcus aureus (MRSA, 17.6%), Coagulase Negative Staphylococci (CoNS, 13%) and Group B Streptococcus (GBS, 7.3%). Trends in the rates of these bacteria demonstrated no significant variation. The knee was the most common joint affected, followed by the shoulder and hip. Shoulder SA was most commonly caused by MRSA while MSSA was the leading causative organism in other joints. GBS was a causative bacterium in shoulder SA significantly more often than in knee or hip infections.

CONCLUSIONS

Although no significant trends were noted in the microbiology of SA over nearly 2 decades, we observed meaningful findings regarding shoulder SA as MRSA was the most common bacterial because of SA in this joint. Prompt joint aspiration, microbiologic testing of synovial fluid and empiric antibiotic therapy that covers MRSA may improve outcomes in SA.

Biofilm Formation by Pseudomonas aeruginosa in a Novel Septic Arthritis Model

Background

Bacterial biofilms generally contribute to chronic infections and complicate effective treatment outcomes. To date, there have been no reports describing biofilm formation in animal models of septic arthritis caused by Pseudomonas aeruginosa (P. aeruginosa). P. aeruginosa is an opportunistic pathogenic bacterium which can lead to septic arthritis. The purpose of this study was to establish a rabbit model of septic arthritis caused by P. aeruginosa to determine whether it leads to biofilm formation in the knee joint cavity. In addition, we explored the role of cyclic di-GMP (c-di-GMP) concentrations in biofilm formation in rabbit models.

Methods

Twenty rabbits were randomly assigned to five groups: PAO1 (n = 4), PAO1ΔwspF (n = 4), PAO1/p_lac-yhjH (n = 4) infection group, Luria–Bertani (LB) broth (n = 4), and magnesium tetrasilicate (talc) (n = 4) control groups. Inoculation in the rabbit knee of P. aeruginosa or with the same volume of sterile LB or talc in suspension (control group) was used to induce septic arthritis in the animal model. In the infection groups, septic arthritis was caused by PAO1, PAO1ΔwspF, and PAO1/p_lac-yhjH strains, respectively. Rabbits were euthanized after 7 days, and pathological examination of synovial membrane was performed. The biofilms on the surface of the synovial membrane were observed by scanning electron microscopy, while the biofilms’ fiber deposition was discriminated using peptide nucleic acid-fluorescence in situ hybridization (PNA-FISH).

Results

A rabbit model for knee septic arthritis induced by P. aeruginosa was successfully established. Scanning electron microscopy revealed that PAO1 strains were surrounded in a self-produced extracellular matrix on the surface of synovial membrane and showed biofilm structures. The biofilms in the fibrous deposition were also observed by PNA-FISH. The PNA-FISH assay revealed that the red fluorescence size in the PAO1ΔwspF group was greater than in PAO1 and PAO1/p_lac-yhjH groups.

Conclusions

This is the first study to provide evidence that P. aeruginosa forms biofilms in a rabbit model for septic knee arthritis. The rabbit model can be used to investigate new approaches to treatment of biofilms in septic arthritis. Furthermore, c-di-GMP is a key signaling molecule which impacts on biofilm formation in rabbit models of knee septic arthritis.

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.

A Rare Case of Septic Knee Arthritis Caused by Clostridium perfringens in a Patient With Colostomy

Septic arthritis of the knee is commonly caused by aerobic organisms. Rarely, it can be caused by Clostridium perfringens, usually due to penetrating trauma. This is a rare case of C. perfringens septic arthritis in a patient with colostomy due to hematogenous spread. The patient was treated successfully with a synovectomy and a prolonged intravenous antibiotic course. The case report summarizes the existing literature on the topic and discusses the diagnosis, management, and prognosis of such cases as well.

The Surgical Treatment of Deep Infection in the Native Shoulder Joint

Background

The overall clinical picture surrounding native shoulder infections, and, in particular, the associated long-term functional outcomes of treatment are presently underreported. The purpose of this study is to examine the demographics, diagnostic and treatment strategies, and functional outcomes of isolated shoulder joint sepsis treated with surgical irrigation and debridement (I&D).

Methods

All patients treated with I&D for native shoulder sepsis between 2007 - 2017 were identified. Those without a minimum of one-year follow-up were excluded. Functional outcomes scores, reoperations, and predictors of poor outcome were evaluated.

Results

Twenty-three patients were included in the final study population. Mean age-adjusted CCI score was 4.1 (SD = 3.4, Range = 0 - 10). Twelve patients (52.2%) were treated with open I&D, while 11 patients (47.8%) were treated arthroscopically. Nine patients (39.1%) required multiple I&Ds (mean total number of I&Ds = 1.7, SD = 1.0, Range: 1 - 4). Five patients (21.7%) had at least one documented reinfection after their initial hospitalization, with the initial recurrence of infection occurring 2 - 15 months after the index procedure. Mean ASES score at final follow-up was 55.3 (SD = 26.7, Range: 5.8 - 98.3) and mean SANE score was 53.3 (SD = 30.6, Range: 0 - 100). Stepwise multiple linear regression modeling identified intravenous drug abuse as the most significant predictor for final ASES score [F(1,18) = 6.12, p = .024, adjusted R² = .254].

Conclusion

Following isolated shoulder joint sepsis, infection clearance and acceptable functional outcomes can be achieved using surgical I&D followed by a course of antibiotics, but outcomes are variable.

[Septic Arthritis of the Hand and Wrist]

This review article addresses the epidemiology, ethology, clinic, diagnostics and therapy of infections of the wrist and small joints of the hand.

Elaboration of a new synovial predictive score of septic origin for acute arthritis on the native joint (RESAS)

OBJECTIVE

To establish a new predictive score for the diagnosis of septic arthritis (SA) according to different synovial fluid (SF) variables.

METHODS

First, we analysed the different clinical, biological and SF variables associated with the diagnosis of SA (according to the Newman's criteria) in a monocentric cohort of acute arthritis (<30 days) (n = 233) (SYNOLACTATE cohort). A new score predictive of SA (RESAS) was created using the independent discriminant variables after multivariate analysis. A value was attributed to each variable of the score according to the weighting based on their likelihood ratio for the diagnosis of SA. RESAS performance was then tested on the first cohort (internal validation) and then checked on a second independent cohort (n = 70) (external validation).

RESULTS

After multivariate analysis, four independent variables of the SF were included for RESAS: (i) purulent SF or white blood cells count ≥70 000/mm3; (ii) absence/presence of crystals; (iii) lactate; and (iv) glucose synovial level. RESAS ranged between -4 and +13 points. The performance of RESAS to predicted SA was excellent with area under the curve (AUC)=0.928 (0.877-0.980) in internal validation and AUC=0.986 (0.962-1.00) in external validation. For a RESAS threshold ≥+4, SA was diagnosed with Se=56.0% (0.371-0.733), Sp=98.1% (0.952-0.993), LR+=29.1 (10.4-81.6) in the first cohort and with Se=91.7% (0.646-0.985), Sp=98.3% (0.909-0.997), LR+=53.2 (7.56-373) in the second cohort.

CONCLUSION

RESAS is a new composite score of four SF variables with excellent performance to predicted SA in acute arthritis population.

Septic Arthritis in Children: A Longitudinal Population-Based Study in Western Australia

Objective

To describe the incidence, risk factors and long-term outcomes in children hospitalised with septic arthritis (SA) in Western Australia (WA).

Methods

We extracted state-wide longitudinally linked administrative health data for patients aged < 16 years with a first diagnostic code of 711.X (ICD9-CM) and M00.X (ICD10-AM) in WA in the period 1990–2010. Annual incidence rates (AIR) per 100,000 with 95% confidence intervals (CIs), prior conditions during a median lookback period of 63.2 [interquartile range (IQR) 19.8–117.1] months and outcomes, including standardised mortality rates (SMR), during a median follow-up of 10 years are reported.

Results

A total of 891 patients [62% male, median age 6.4 (IQR 1.9–10.6) years with 34% aged < 3 years] were admitted for SA during the observation period. The overall AIR (per 100,000) was 9.85 (95% CI 4.79–14.41), and was higher in Indigenous Australians [34.9 vs. 5.5 (non-Indigenous), p < 0.001] and in males [11.9 vs. 7 (females), p < 0.01]; AIR showed no temporal or seasonal variation. Knees (43.9%), hips (34.6%) and ankles (13.3%) were most frequently affected, with Staphylococci predominant (49%) in patients with positive cultures (41.5%). Prior infection(s) (40.4%) and respiratory disease (7%) were the main pre-existing morbidities. Median hospital stay was 4.0 (IQR 2–8) days, with 1.9% requiring admission to the intensive care unit and 10.4% requiring readmission within 30 days. During follow-up, 26 patients (3.1%) developed osteomyelitis, nine patients were diagnosed with osteoarthrosis (1.1%) and five patients (0.6%) underwent joint replacement. Female patients developed other serious infections more often than male patients (40.5 vs. 27.1%, p < 0.01), as well as other comorbidities (Charlson Comorbidity Index > 0: 34.6 vs. 27.2%, p = 0.02), including diabetes (4.2 vs. 0%; p = 0.001), cardiovascular events (4.2 vs 1.4%, p = 0.002) and chronic arthritis (1 vs. 0%, p = 0.05). The crude mortality rate was low (0.3%), with 99.4% survival at 180 months and no increase in the SMR.

Conclusions

The incidence of SA in children in WA did not change over the 20-year observation period. SA did not lead to excess mortality, but bone and joint complications developed in 5% of patients. The high propensity to comorbid conditions in this young cohort suggests an underlying role of comorbidity in SA development.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40744-021-00307-x.

As more children are living with complex and chronic conditions, we investigated whether children in Western Australia (WA) have become more prone to joint infections. During a 20-year observation period we collected health data for all children admitted to any hospital in the state with an infected joint and recorded their health outcomes. We found that joint infection occurs in nearly ten out of 100,000 children each year, but we saw no change in the frequency over time. We did observe higher rates in Indigenous children (35/100,000) than in non-indigenous children (6/100,000) but found no noticeable influence of the seasons on the frequency of joint infections. Knees, hips and ankles were most often affected, and 15% had additional bone infection. Children needed to be treated in hospital for 4–5 days, and only a small minority (1.2%) were so ill they needed intensive care. Joint infections led to chronic, long-term complications in about 5% of patients, but we found no evidence that joint infections increased the risk of death compared to children in the general population.

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

OBJECTIVE

This national cohort study investigated the incidence, site-specific mortality and prognostic factors of native septic arthritis (SA).

METHODS

Tapping Taiwan's National Health Insurance Research Database, we identified inpatients with newly diagnosed SA between 1998 and 2012. They were categorized by site of infection and followed to calculate 30-day, 90-day and 1-year mortality. Predictors of mortality were calculated using Cox models.

RESULTS

A total of 31 491 patients were identified as having SA, the most common site of infection being the knee (50.1%), followed by the hip (14.4%), other sites (26.8%), the shoulder (5.5%) and multiple sites (1.2%). Knee joint involvement was the most common site for all subgroups. Incidence increased from 9.8/105 in 1998 to 13.3/105 in 2012. The 30-day, 90-day and 1-year mortality rates were 4.3, 8.6 and 16.4% respectively. Predictors for mortality were hip infection, shoulder infection, multiple-site infection, being male, age ≥65 years old and comorbidities. We derived a mortality scoring model over age/SA site/comorbidity, and age ≥65 years old had the greatest risk contribution to mortality. No matter whether 1-month, 3-month or 1-year mortality was being considered, patients with the higher risk scores had the higher mortality rates (P < 0.0001).

CONCLUSION

SA is an emerging infectious disease with a rising incidence, long duration of hospital stay and high mortality rate. The most common affected joint was knee for all subgroups. Patients aged ≥65 years old had a high SA incidence and the greatest risk contribution.

Clinical Characteristics and Causative Pathogens of Infective Arthritis and Risk Factors for Gram-Negative Bacterial Infections

Background

The aim of this study was to describe the clinical and microbiological characteristics of infective arthritis and to analyze risk factors for Gram-negative bacterial infections that cause infective arthritis.

Materials and Methods

Patients admitted between 2009 - 2018 with infective arthritis in a single-tertiary hospital were evaluated retrospectively.

Results

A total of 181 patients were enrolled in this study. Of them, 135 were native joint infection patients and 46 were prosthetic joint infection patients. The most common site of infective arthritis was the knee (63.6%), followed by the shoulder (17.7%), and the hip (9.9%). The most frequently identified microorganisms were Staphylococcus aureus (51.1%), followed by Streptococci sp. (21.1%), Enterobacteriaceae (8.4%), and coagulase-negative-Staphylococci (CNS; 8.4%). Infections due to Gram-negative bacteria and fungi made up 13.7% and 3.2% of all cases, respectively. Additionally, 20% and 4.2% of the cases involved methicillin-resistant S. aureus (MRSA) and MRCNS. We found that bacteriuria, infective arthritis in the hip, and steroid use at admission are independent risk factors for Gram-negative bacterial infections.

Conclusion

Infective arthritis with methicillin-resistant microorganisms reached up to about 25% in a single-tertiary hospital in Korea. In case of suspected urinary tract infection, infective arthritis of the hip joint, or steroid use at admission time among infective arthritis patients, empirical treatment covering Gram-negative microorganisms can be considered.

Risk Factors, Screening, and Treatment Challenges in Staphylococcus aureus Native Septic Arthritis

Background

Staphylococcus aureus is the most common cause of native septic arthritis. Few studies have characterized this disease during the US opioid epidemic. The role of methicillin-resistant Staphylococcus aureus (MRSA) nasal screening in this disease has not been elucidated. We sought to identify risk factors and outcomes for S. aureus native septic arthritis and to evaluate MRSA screening in this disease.

Methods

A retrospective cohort study of native septic arthritis patients (2012–2016) was performed. Demographics, risk factors, and outcomes were compared between Staphylococcus aureus and other native septic arthritis infections. Sensitivity, specificity, and predictive values of MRSA screening were assessed.

Results

Two hundred fifteen cases of native septic arthritis were included. S. aureus was cultured in 64% (138/215). MRSA was cultured in 23% (50/215). S. aureus was associated with injection drug use (odds ratio [OR], 4.33; 95% CI, 1.74–10.81; P = .002) and switching antibiotics (OR, 3.92; 95% CI, 1.01–21.38; P = .032). For every 10-year increase in age, the odds of S. aureus decreased (OR, 0.72; 95% CI, 0.60–0.87; P = .001). For 1-unit increases in Charlson comorbidity index score, the odds of S. aureus decreased (OR, 0.82; 95% CI, 0.73–0.91; P = .0004). MRSA screening during admission demonstrated a sensitivity of 0.59, specificity of 0.96, positive predictive value of 0.85, and negative predictive value of 0.84 for MRSA native septic arthritis.

Conclusions

The opioid epidemic may be contributing to a demographic shift in native septic arthritis to younger, healthier individuals. S. aureus native septic arthritis has unique risks, including injection drug use. MRSA screening may be useful to rule in MRSA native septic arthritis.

Primarily treated patients versus referred patients in the treatment of native septic arthritis of digits: a retrospective comparative study

BACKGROUND

Septic arthritis of digits needs urgent treatment. When treatments delayed or insufficient, patients may be referred to the upper-level hospital due to uncontrolled infection. We reviewed the treatment history of referred patients and compared the microorganisms and the clinical course of both primary and referred patients as relevant studies are rare.

METHODS

In this retrospective review of consecutive case series, 45 patients (primary, n = 11; referred, n = 34) were treated with multiple irrigation and debridement. Cefazolin was used as empiric antibiotics, then changed according to microbiologic study. Previously used antibiotics, treatment delay, surgical history of the referred patients were reviewed. Identified microorganisms, required surgical intervention, hospital stay, radiologic outcome, functional outcomes were compared between both groups.

RESULTS

In the referred patients, methicillin-resistant Staphylococcus aureus (MRSA) was commonly found and cefazolin was susceptible in only 15% of the cases. Longer hospital stay, prolonged antibiotic therapy, more surgical intervention including flap surgery was required to treat the referred patients. Postoperative pain was not severe in daily activities, but the final range of motion was significantly less in the referred patients compared to the primary patients.

CONCLUSIONS

This study suggests that in the treatment of uncontrolled septic arthritis of the digits, antibiotic agents covering MRSA may shorten the duration of antibiotic therapy in areas of high MRSA incidence. Besides, more number of I & D including flap surgery may be required for the referred patients compared with the primary patients. These findings can help the surgeon in setting up a treatment plan or in counseling of referred patients with uncontrolled septic arthritis of the digits.

Lipoxin A4 impairs effective bacterial control and potentiates joint inflammation and damage caused by Staphylococcus aureus infection

Staphylococcus aureus is the main cause of septic arthritis in humans, a disease associated with high morbidity and mortality. Inflammation triggered in response to infection is fundamental to control bacterial growth but may cause permanent tissue damage. Here, we evaluated the role of Lipoxin A₄ (LXA₄ ) in S aureus-induced arthritis in mice. Septic arthritis was induced by S aureus injection into tibiofemoral joints. At different time points, we evaluated cell recruitment and bacterial load in the joint, the production of pro-inflammatory molecules, and LXA₄ in inflamed tissue and analyzed joint damage and dysfunction. LXA₄ was investigated using genetically modified mice or by pharmacological blockade of its synthesis and receptor. CD11c⁺ cells were evaluated in lymph nodes by confocal microscopy and flow cytometry and dendritic cell chemotaxis using the Boyden chamber. Absence or pharmacological blockade of 5-lipoxygenase (5-LO) reduced joint inflammation and dysfunction and was associated with better control of infection at 4 to 7 days after the infection. There was an increase in LXA₄ in joints of S aureus-infected mice and administration of LXA₄ reversed the phenotype in 5-LO^-/- mice. Blockade or absence of the LXA₄ receptor FPR2 has a phenotype similar to 5-LO^-/- mice. Mechanistically, LXA₄ appeared to control migration and function of dendritic cells, cells shown to be crucial for adequate protective responses in the model. Thus, after the first days of infection when symptoms become evident therapies that inhibit LXA₄ synthesis or action could be useful for treatment of S aureus-induced arthritis.

A case of deep vein thrombosis associated with methicillin sensitive Staphylococcal aureus genu septic arthritis

Septic arthritis caused by bacteria Gram positive Staphylococcus aureus (S. aureus) infection has been widely reported from Europe and the United States. This case presentation reported the first Staphylococcal septic arthritis, preceded by systemic erythroderma skin lesions from aregional hospital in Surabaya, Indonesia. Radiology imaging was used for confirming the defect. Joint fluid aspirate from the affected knee joint lesion was sent for joint fluid analysis and microbiology culture. The analysis showed infiltration of neutrophil inflammatory cells. S. aureus was isolated on culture and demonstrated catalase positive and coagulase positive reactions. Antimicrobial susceptibility testing was performed to determine the appropriate selection of antibiotics. Clindamycin was used for treatment and the complicated occurrence of deep vein thrombosis was treated with anticoagulant. Awareness of this disease and its progression to its complication deep vein thrombosis is required to understand the burden of this disease.

Patients with surgically treated culture-negative native joint septic arthritis have less severe disease and better outcomes

Background: Patients with culture-negative septic arthritis patients are often treated surgically but might be successfully managed medically. We compared clinical characteristics and outcomes in patients with culture negative and culture positive native joint monoarticular septic arthritis.Methods: This retrospective study included all patients age ≥18 years admitted to a single, tertiary-care hospital between 1998 and 2015 with native joint monoarticular SA and treated with antibiotics and surgery.Results: Of 306 patients, 85 had negative and 221 had positive cultures. Mean C-reactive protein (p < .01) and mean percentage of peripheral polymorphonuclear cells (p = .01) were higher in culture-positive patients who had higher intensive care unit admission rates (16.7% vs. 4.7%, respectively, [p < .01]), longer length of hospital stay (11.4 vs. 7.1 days, respectively, [p < .01]) and higher mortality rates within 30 days (0% vs. 5.5%, respectively,[p = .02]). Of culture-negative patients, 28.6% received an alternative diagnosis within one year. Logistic regression models showed that culture positive patients had an adjusted odds ratio for length of stay of 4.5 (2.69, 7.51), intensive care unit admission of 5.76 (1.31, 25.22), discharge to rehabilitation of 4.7 (2.28, 9.71) and an alternative diagnosis within one year of 0.05 (0.02, 0.15) compared to culture negative patients.Conclusion: Patients with culture-negative native joint septic arthritis had less severe disease, better outcomes and higher rates of alternative diagnosis within one year than patients with positive cultures.

Two-Stage Primary Arthroplasty of Native Hips and Knees That Had Previously Failed Treatment for Septic Arthritis: A Single-Center Experience

Background

Patients with a history of degenerative joint disease secondary to an acute or remote episode of septic arthritis of the native knee or hip present a unique challenge for the orthopaedic surgeon. This study describes our experience with two-stage primary arthroplasty for such patients.

Methods

We reviewed 42 patients with a history of septic arthritis treated with two-stage primary arthroplasty between 2008 and 2018. Patients were evaluated using modified Harris Hip Score, Knee Society Score (KSS), and KSS functional component (KSSF). Paired t-tests were used to compare changes for continuous variables within cohorts. Multivariate linear and logistic regression models were constructed to determine predictors of outcomes and complications.

Results

At a mean of 3.3-year follow-up, there were 14 (33.3%) complications and the infection cure rate was 95.2%. On average, patients improved in the modified Harris Hip Score (42.9 ± 11.8 vs 83.3 ± 11.1, P < .001), KSS (35.9 ± 16.9 vs 80.1 ± 16.6, P < .001), KSSF (38.0 ± 15.1 vs 71.5 ± 24.0, P < .001), knee flexion (90.9 ± 14.9 vs 100.5 ± 17.1), and hip flexion (73.8 ± 21.2 vs 102.1 ± 11.8, P < .001). Age (β: -0.78, P = .004) was independently associated with lower Harris Hip Score in the hip cohort. There were no independent predictors of the KSS or KSSF. The erythrocyte sedimentation rate (odds ratio: 1.07, P = .043) and C-reactive protein (odds ratio: 1.43, P = .018) at stage 2 were independently associated with a higher likelihood of complications at the final follow-up.

Conclusion

Patients with a history of native septic arthritis of the hip and knee, and secondary end-stage degenerative joint disease, showed significant postoperative improvements and a high rate of complications after two-stage primary total joint arthroplasty. Despite improvements, some patients may necessitate a third operation because of the incidence of reinfection and spacer exchange. This information should be used to counsel patients who present with this challenging clinical scenario.

Arthroscopic débridement has similar 30-day complications compared with open arthrotomy for the treatment of native shoulder septic arthritis: a population-based study

HYPOTHESIS

This study aimed to determine whether there are significant differences in 30-day perioperative complications between arthroscopic and open débridement (irrigation and débridement [I&D]) for septic arthritis (SA) of the shoulder using the American College of Surgeons National Surgical Quality Improvement Program database.

METHODS

Patients undergoing arthroscopic or open I&D of the native shoulder from 2006-2016 were identified in the National Surgical Quality Improvement Program database. Those with a diagnosis of SA were included in the study. Patients with a concurrent diagnosis of osteomyelitis around shoulder (n = 25) or polyarthritis (n = 2) were excluded from the study. Patient demographics, comorbidities, and complications were compared between the groups. Poisson regression, which controlled for age and American Society of Anesthesiologists (ASA) score, was used to calculate the relative risks with 95% confidence intervals for minor adverse events, serious adverse events, total adverse events, and unplanned reoperations between the 2 treatment groups, with significance set at P < .0125 after Bonferroni correction.

RESULTS

Overall, 147 and 57 patients underwent arthroscopic and open I&D, respectively, for SA of the shoulder. Patients in the open I&D group were more likely to be smokers (P = .0213), whereas patients in the arthroscopy group had higher ASA scores (P = .0008). After controlling for age and ASA score, we found no significant differences in the risk of minor adverse events (P = .0995), serious adverse events (P = .2241), total adverse events (P = .1871), or unplanned reoperations (P = .3855).

CONCLUSION

Arthroscopic débridement appears to be a safe alternative to open débridement for SA of the native shoulder. The incidence and risk of 30-day perioperative complications are similar after arthroscopic and open I&D for SA of the shoulder.

Synovial Cell Count Poorly Predicts Septic Arthritis in the Presence of Crystalline Arthropathy

Introduction: A synovial cell count greater than 50,000/mm³ is the threshold most commonly used to diagnose septic arthritis. This lab value may be nonspecific in the setting of crystalline arthropathy. The purpose of this study was to evaluate the accuracy of diagnosing septic arthritis using a synovial cell count cut-off of 50,000/mm³ in the setting of crystalline arthropathy.

Methods: This was a retrospective review of joint aspirations performed between July 1^st, 2013 and June 30^th, 2016. Synovial fluid samples were evaluated for cell count, crystals, Gram stain, and culture. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the synovial markers were calculated.

Results: During the study period, 738 joint aspirations were sent for testing, of which 358 aspirations in 348 patients met inclusion criteria. There were 49 (13.7%) cases of culture-positive septic arthritis, and 47 patients underwent surgical irrigation and debridement. Gout and pseudogout crystals were present in 163 aspirates (45.5%). Three joints (0.8% overall rate) had concomitant crystalline arthropathy and septic arthritis, each of which had a synovial WBC ≥85,000/mm³. Increasing the WBC count cutoff to 85,000/mm³ demonstrated a specificity of 100%, but a PPV of 12.0%.

Conclusions: A cut-off of 85,000/mm³ may be more appropriate to diagnose concomitant septic arthritis and crystalline arthropathy. We recommend medical management and observation in patients with crystal-positive joint aspirations unless the synovial cell count is elevated above 85,000/mm³. Prospective studies using this treatment guideline are needed to evaluate its validity and accuracy.

Clinical Results after Arthroscopic Treatment of Septic Shoulder with Proximal Bone Involvement

BACKGROUND

If osteomyelitis is confined to the proximal humerus, arthroscopic debridement with multiple punctures at the infected bone might be sufficient to eradicate the septic shoulder with bone involvement.

MATERIALS AND METHODS

From 2005 to 2017, 15 patients received arthroscopic debridement with multiple punctures. We included patients with septic shoulder arthritis with proximal bone involvement and excluded patients with glenohumeral joint destruction or extension of bone involvement to the diaphysis of the humerus. We performed multiple punctures for drainage of proximal humerus after complete arthroscopic debridement of septic soft tissue. Infection laboratory studies and postoperative magnetic resonance image were evaluated. For clinical outcome measurements, range of motion, pain visual analog scale, functional visual analog scale, American shoulder elbow surgeon scores, constant scores, and simple shoulder test were evaluated.

RESULTS

There were 11 males and 4 females with a mean age of 53 years (range 28-73 years). Mean follow-up was 32 months (range 12-115 months). There was no reinfection case. The postoperative C-reactive protein levels were normalized in all. The postoperative magnetic resonance image showed no bony involvement of the proximal humerus in all patients except one patient. The clinical scores and range of motion were significantly improved postoperatively. Six patients underwent secondary surgery for rotator cuff tear at a mean time period of 25 months (range 4-104 months) from the index period.

CONCLUSION

Septic shoulder with proximal bone involvement can be successfully treated with arthroscopic debridement with multiple punctures.

LEVEL OF EVIDENCE

Level IV, treatment study.

[Native joint infections]

Joint infections are a great challenge for the treating physicians. Infection of a native joint can result in the rapid destruction of the joint if treatment is inadequate or delayed and is associated with severe life-threatening diseases, such as sepsis. This article presents a detailed overview of the treatment of joint infections of native joints with a focus on the diagnostic approach and treatment decisions. Infections in native joints are caused either endogenously by hematogenic spreading or are caused by exogenous factors. A relevant proportion of joint infections in native joints occur in connection with iatrogenic measures, such as operations, synovial punctures and joint infiltrations. Fundamentally, acute infections represent an orthopedic surgical emergency, which is associated with the necessity for immediate operative measures. The best possible success can only be achieved by an interaction between early diagnosis, an adequate surgical approach and a tailor-made anti-infectious treatment. This is also the case with periprosthetic infections, which will be dealt with in detail in a second article.

A Case Report of Pneumococcal Septic Arthritis Following a Respiratory and Gastrointestinal Prodrome with Accompanying Literature Review

We report an uncommon case of septic arthritis of the ankle from a Streptococcus pneumoniae infection and provide an update of the literature reported since 2002. A 58-year-old female presented to the hospital with right ankle pain and an inability to bear weight. She reported a history of productive cough, vomiting, diarrhea, and subjective fevers 4 days earlier. Streptococcus pneumonia was identified in her ankle aspirate, and she was treated urgently with operative incision and debridement, followed by postoperative intravenous antibiotics. At her 7-week follow-up, she demonstrated complete resolution of symptoms and near-complete recovery of range of motion. This case demonstrates the importance of early identification, as the majority of patients recover fully with prompt treatment. The literature review included 44 cases of pneumococcal septic arthritis and found that the knee was the most commonly affected joint, followed by the shoulder and ankle. Blood cultures were positive for S. pneumoniae in 27 of 38 adults (71%) and 4 of 6 children (67%). Comorbid conditions were present in 32 of 38 adults (84%) and 4 of 7 children (57%), the most frequent of which were alcoholism and osteoarthritis in adults and malignancy or immunosuppression in children. Additionally, roughly half of included adults had an extra-articular focus of pneumococcal disease, most frequently pneumonia. Operative treatment was undertaken in 32 of 38 adults (84%) and all 7 children. Of adults with data available, 24 of 33 (73%) recovered with complete joint function, compared with 5 of 7 children (71%).