Septic Arthritis Infection Research Articles

Putative mRNA Biomarkers for the Eradication of Infection in an Equine Experimental Model of Septic Arthritis.

Septic arthritis (SA) in horses has long-term health implications. The success of its resolution hinges on the implementation of early, aggressive treatment, which is often sustained over a prolonged period. Common diagnostic methods do not allow for the reliable detection of the eradication of joint infection. A potential alternative is the discovery and characterization of mRNA biomarkers. The purpose of this study was to identify potential mRNA biomarkers for the eradication of joint infection in equine SA and to compare their expression with our previously published proteomics data. In addition, the transcriptomics data were compared to the mRNA biomarker panel, SeptiCyte Lab, used to distinguish sepsis from non-septic shock in humans. A comparative transcriptomics analysis of synovial fluid from the SA joints of five horses with active infection and subsequent post-treatment eradicated infection in the same joints and five horses with non-septic synovitis was performed. Eight novel mRNA transcripts were identified that were significantly upregulated (>3-fold) in horses with active SA compared to horses post-eradication of infection after treatment and horses with non-septic synovitis. Two proteins in our proteomics data corresponded to these mRNA transcripts, but were not statistically different. The transcripts used in the SeptiCyte test were not differentially expressed in our study. Our results suggest that mRNA may be a useful source of biomarkers for the eradication of joint infection in horses and warrants further investigation.

Incidental findings involving the temporomandibular joint on computed tomography and magnetic resonance imaging.

The temporomandibular joint (TMJ) is frequently imaged in head and neck computed tomography (CT) and magnetic resonance imaging (MRI) studies. Depending on the indication for the study, an abnormality of the TMJ may be an incidental finding. These findings encompass both intra- and extra-articular disorders. They may also be related to local, regional or systemic conditions. Familiarity with these findings along with pertinent clinical information helps narrow the list of differential diagnoses. While definitive diagnosis may not be immediately apparent, a systematic approach contributes to improved discussions between clinicians and radiologists and better patient management.

Discovery proteomics for the detection of putative markers for eradication of infection in an experimental model of equine septic arthritis using LC-MS/MS

Septic arthritis (SA) is a life-threatening condition in horses, and identifying eradication of infection in equine SA is challenging. This study explored the discovery of putative biomarkers for the eradication of joint infection in horses. We performed proteomics analysis of synovial fluid (SF) and plasma from horses with experimental SA, non-septic lipopolysaccharide-induced arthritis, and controls. The point of eradication of infection in horses with SA was determined previously. We compared spectral intensities between groups as well as before and after the eradication of infection. Twenty-six differentially abundant proteins were identified, which were upregulated in SF of horses with SA compared to the other groups, as well as compared to the same horses post-eradication of infection. In plasma, we did not identify differentially abundant proteins. Differentially abundant proteins in SF were of cellular origin and their biological functions included ubiquitination, signal transduction, apoptosis etc. The difference in their relative abundance between experimental groups was ≥10-fold compared to the abundance expected based on the difference in cell count alone (2-fold). Since most of cells in joints with bacterial infection are neutrophils, we suggest that the variable abundance of neutrophil- and cell-associated proteins represent potential biomarkers of eradication of infection in equine SA. SignificanceSeptic arthritis is an important condition in horses, which can be life-threatening. At present, identifying eradication of infection in cases of equine septic arthritis is challenging. In this study, we performed a global proteomics analysis of synovial fluid and plasma in horses with experimental septic arthritis and identified 26 differentially abundant proteins compared to non-septic arthritis and post eradication of infection. The results of this study provide the basis for further characterization of the differentially abundant proteins and identification of clinically relevant biomarkers of septic arthritis in horses.

A comparison of tuberculous and bacterial native joint septic arthritis infections in a retrospective cohort: Presentation characteristics, outcomes and long term follow up

• Patients with bacterial versus tuberculous septic arthritis had significantly higher CRP levels and neutrophil counts. • A CRP level above 100 mg/L conferred an odds ratio of 46 for bacterial infection. • 51% of bacterial septic arthritis cases were asymptomatic at last follow up compared to 72% of tuberculous cases. This retrospective observational cohort study aimed to characterise and compare the demographics, initial laboratory tests and outcomes between patients with large-joint bacterial septic arthritis (BSA) and tuberculous septic arthritis (TBSA). All patients with a culture from a large, native joint growing either non-mycobacterial bacteria or Mycobacterium tuberculosis between 1 January 2012 and 1 October 2018 in our institution were included. Clinical details and admission laboratory values were obtained from patient records. Comparisons were made by Mann-Whitney U, chi-squared tests, and logistic regression analysis. We identified 64 BSA and 29 TBSA. On average, the BSA cases were older, had higher CRP levels and neutrophil counts and lower albumin levels. The odds ratio for having a BSA was 46 in cases with a CRP greater than 100 mg/L (95% confidence interval (CI) 8.5–850, p < 0.001) and 24 with a neutrophil count greater than 7.5x10 9 (95% CI 6.1–160, p < 0.001). 51% of BSA were asymptomatic at last follow up compared to 72% of TBSA. 14% of the BSA cases died during admission; there were no deaths in the TBSA group. Significant differences exist between patients with BSA and TBSA. Whilst no test is sufficient to exclude BSA, a raised neutrophil count or a CRP greater than 100 mg/L significantly increases the odds of a bacterial aetiology. Patients with BSA had worse long-term outcomes and higher incidence of inpatient mortality.

Native Joint Infections by Aspergillus Species.

Background: Septic arthritis due to Aspergillus spp. represents a rare, but severe disease. Nevertheless, clear guidelines regarding most effective medical treatment have not yet been established. The present study is a literature review of all reported cases of fungal septic arthritis due to Aspergillus spp, in order to clarify epidemiology, as well as the medical and operative management and their outcome. Methods: A meticulous review of all published septic arthritis infections due to Aspergillus has been conducted. Information regarding demographics, causative fungus, antifungal treatment (AFT), surgical intervention, as well as the infection’s outcome were recorded and evaluated. Results: A total of 30 Aspergillus spp. strains from 29 hosts have been studied. The patients’ mean age was 45.8 years. The most commonly affected joint was the knee (45.7%), while the predominant symptom was joint pain (62%). Most patients were immunocompromised (72.4%). Diagnosis was established through cultures and/or histopathology. Aspergillus fumigatus was the most common responsible fungi (63.3%), followed by A. flavus (16.6%) and A. terreus (10%). Regarding AFT, the preferred agent proved to be Amphotericin B (14 cases; 48.3%), followed by voriconazole (11; 37.9%), while the mean AFT duration was 5.6 months. In most cases surgical treatment was also performed (in 4 cases no surgery was reported). Treatment was effective in 20 cases (69%). Conclusions: Septic arthritis caused by Aspergillus spp. represents a severe clinical entity. It seems that, with the available data, prolonged AFT along with surgical intervention is the preferred management of this infection, while identification of the responsible fungus is of utmost importance.

The utility of echocardiography in paediatric patients with musculoskeletal infections and bacteremia.

PurposeThe clinical utility of echocardiography in the setting of a positive blood culture in paediatric patients presenting with osteomyelitis (OM) and/or septic arthritis (SA).MethodsRetrospective review between 2013 and 2019: Patients < 18 years with OM, SA or combined infection (OM+SA) were included. Patients were excluded for immunodeficiency, loss of follow-up or penetrating infection. Charts with positive blood cultures were reviewed for echocardiography on that admission. Demographic variables were compared utilizing the Student’s t-test and Fisher’s exact test. A multivariable linear regression model was constructed to examine the association between echocardiography and length of stay, controlling for age, sex, fever, white blood cell (WBC) on admission, antibiotic administration and surgery performed.ResultsOf 157 patients with OM, SA or combined infection, 44 had a positive blood culture. In all, 26 had an echocardiogram, and none showed endocarditis. Echocardiography was independently associated with a 6.2-day length of stay increase. WBC count and surgical intervention demonstrated a trend toward significance in length of stay, with each WBC unit increase associated with a 0.53-day increase. Surgical intervention was associated with an average 6.3-day length of stay decrease.ConclusionNo patient had a positive echocardiogram, and no changes in management were initiated. However, an echocardiogram increased stay by 6.2 days. In addition to costs associated with increased stay, patients were billed between $1460 and $1700 per echocardiogram. The utility of echocardiograms in the setting of bacteremia associated with musculoskeletal infections in the paediatric population should be re-examined, and guidelines should be updated to reflect the cost-benefit analysis.Level of Evidence:III

Predicting adjacent infections in pediatric septic arthritis: Do predictive criteria extrapolate across geographic regions?: Predicting Periarticular Infection in the Southeast

PurposeThis study aims to assess previously determined predictive criteria for presence of adjacent infection in septic arthritis within a Southeastern United States (US) pediatric population. ResultsThe sensitivity, specificity, positive predictive value, and negative predictive value of the Rosenfeld criteria were: 91.7%, 22.7%, 39.3%, and 83.3%, respectively. The patients with periarticular infection were more likely to have positive blood cultures than those with isolated septic arthritis. There was no difference in likelihood of secondary surgical intervention. ConclusionsPreviously defined criteria to predict adjacent infection in pediatric septic arthritis did not demonstrate external validity in a Southeastern US pediatric population.

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.MethodsA 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.ResultsTwo 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.ConclusionsThe 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.

Bacterial septic arthritis infections associated with intra-articular injection practices for osteoarthritis knee pain-New Jersey, 2017.

In March 2017, the New Jersey Department of Health received reports of 3 patients who developed septic arthritis after receiving intra-articular injections for osteoarthritis knee pain at the same private outpatient facility in New Jersey. The risk of septic arthritis resulting from intra-articular injection is low. However, outbreaks of septic arthritis associated with unsafe injection practices in outpatient settings have been reported. An infection prevention assessment of the implicated facility's practices was conducted because of the ongoing risk to public health. The assessment included an environmental inspection of the facility, staff interviews, infection prevention practice observations, and a medical record and office document review. A call for cases was disseminated to healthcare providers in New Jersey to identify patients treated at the facility who developed septic arthritis after receiving intra-articular injections. We identified 41 patients with septic arthritis associated with intra-articular injections. Cultures of synovial fluid or tissue from 15 of these 41 case patients (37%) recovered bacteria consistent with oral flora. The infection prevention assessment of facility practices identified multiple breaches of recommended infection prevention practices, including inadequate hand hygiene, unsafe injection practices, and poor cleaning and disinfection practices. No additional cases were identified after infection prevention recommendations were implemented by the facility. Aseptic technique is imperative when handling, preparing, and administering injectable medications to prevent microbial contamination. This investigation highlights the importance of adhering to infection prevention recommendations. All healthcare personnel who prepare, handle, and administer injectable medications should be trained in infection prevention and safe injection practices.

Pediatric Septic Arthritis and Osteomyelitis in the USA: A National KID Database Analysis.

Prior reports suggest that osteoarticular infections may be increasing over time. We sought to determine if incidence rates, median in-hospital costs, and length of stay (LOS) of osteomyelitis, septic arthritis (SA), and combined infections have changed over time for pediatric patients, and how they compare to previously reported rates. The Kids' Inpatient Database (KID), a US national sample of pediatric hospital discharge records from 1997, 2000, 2003, 2006, 2009, and 2012, was used to determine yearly estimated counts of infections in children 20 years of age or younger. US census data was used to calculate yearly incidence rates. Trend tests using linear contrast analysis were used to compare estimated median LOS and inflation-adjusted median costs over time for each type of infection. From 1997 through 2012, the incidence rate of osteomyelitis increased from 7.9 to 10.5 per 100,000, SA was unchanged from 5.3 to 5.2 per 100, and combined infections increased from 0.8 to 1.3 per 100,000. Median LOS from 1997 to 2012 showed no significant change for osteomyelitis (5.0 to 4.9days), SA (4.4 to 4.1days), or combined infections (6.5 to 6.8days). Median in-hospital costs from 1997 to 2012 increased for osteomyelitis ($7735 to $11,823), SA ($5041 to $10,574), and combined infections ($12,691 to $16,260). In pediatric patients, the estimated incidence rate of SA appeared stable, while rates of osteomyelitis and combined infections increased. These estimated rates fall within previously reported ranges. Despite stable LOS, costs have increased over time.

Presentation Number OI-30 - Outbreak of Bacterial Septic Arthritis Infections Associated with Intra-Articular Injections- New Jersey 2017

Background: In March 2017, the New Jersey Department of Health received reports of three patients who developed bacterial septic arthritis after receiving intra-articular injections for osteoarthritis knee pain at the same private outpatient facility in New Jersey. Bacterial septic arthritis is an uncommon but life-threatening condition; the risk of septic arthritis resulting from intra-articular injection is low. However, previous outbreaks of septic arthritis associated with unsafe injection practices in outpatient settings have been reported.

Clinical Features and Outcomes of Children with Culture-Negative Septic Arthritis.

Septic arthritis is a serious infection, but the results of blood and joint fluid cultures are often negative in children. We describe here the clinical features and management of culture-negative septic arthritis in children at our hospital and their outcomes. We performed a retrospective review of a cohort of children with septic arthritis who were hospitalized at Children's Hospital of Philadelphia between January 2002 and December 2014. Culture-negative septic arthritis was defined as a joint white blood cell count of >50000/μL with associated symptoms, a clinical diagnosis of septic arthritis, and a negative culture result. Children with pretreatment, an intensive case unit admission, Lyme arthritis, immunodeficiency, or surgical hardware were excluded. Treatment failure included a change in antibiotics, surgery, and/or reevaluation because of a lack of improvement/worsening. We identified 157 children with septic arthritis. The patients with concurrent osteomyelitis (n = 28) had higher inflammatory marker levels at presentation, had a longer duration of symptoms (median, 4.5 vs 3 days, respectively; P < .001), and more often had bacteremia (46.4% vs 6.2%, respectively; P < .001). Among children with septic arthritis without associated osteomyelitis, 69% (89 of 129) had negative culture results. These children had lower C-reactive protein levels (median, 4.0 vs 7.3 mg/dL, respectively; P = .001) and erythrocyte sedimentation rates (median, 39 vs 51 mm/hour, respectively; P = .01) at admission and less often had foot/ankle involvement (P = .02). Among the children with culture-negative septic arthritis, the inpatient treatment failure rate was 9.1%, and treatment failure was more common in boys than in girls (17.1% vs 3.8%, respectively; P = .03). We found no association between treatment failure and empiric antibiotics or patient age. No outpatient treatment failures occurred during the 6-month follow-up period, although 17% of the children discharged with a peripherally inserted central catheter line experienced complications, including 3 with bacteremia. The majority of septic arthritis infections at our institution were culture negative. Among patients with culture-negative infection, empiric antibiotics failed for 9% and necessitated a change in therapy. More sensitive diagnostic testing should be implemented to elucidate the causes of culture-negative septic arthritis in children.

Validating an Algorithm to Predict Adjacent Musculoskeletal Infections in Pediatric Patients With Septic Arthritis.

Septic arthritis is frequently associated with adjacent infections including osteomyelitis and subperiosteal and intramuscular abscesses. While often clinically indiscernible from isolated septic arthritis, the diagnosis of adjacent infections is important in determining the need for additional surgical intervention. MRI has been used as the diagnostic gold standard for assessing adjacent infection. Routine MRI, however, can be resource-intensive and delay surgical treatment. In this context, there is need for additional diagnostic tools to assist clinicians in determining when to obtain preoperative MRI in children with septic arthritis. In a previous investigation by Rosenfeld et al., an algorithm, based on presenting laboratory values and symptoms, was derived to predict adjacent infections in septic arthritis. The clinical applicability of the algorithm was limited, however, in that it was built from and applied on the same population. The current study was done to address this criticism by evaluating the predictive power of the algorithm on a new patient population. (1) Can a previously created algorithm used for predicting adjacent infection in septic arthritis among pediatric patients be validated in a separate population? Records for all pediatric patients (1-18 years old) surgically treated for suspected septic arthritis during a 3-year period were retrospectively reviewed (109 patients). Of these patients, only those with a diagnosis of septic arthritis confirmed by synovial fluid analysis were included in the study population. Patients without confirmation of septic arthritis via synovial fluid analysis, Gram stain, or culture were excluded (34 patients). Patients with absence of MRI, younger than 1 year, insufficient laboratory tests, or confounding concurrent illnesses also were excluded (18 patients), resulting in a total of 57 patients in the study population. Five variables which previously were shown to be associated with risk of adjacent infection were collected: patient age (older than 4 years), duration of symptoms (> 3 days), C-reactive protein (> 8.9 mg/L), platelet count (< 310 x 10 cells/µL), and absolute neutrophil count (> 7.2 x 10 cells/µL). Adjacent infections were determined exclusively by preoperative MRI, with all patients in this study undergoing preoperative MRI. MR images were read by pediatric musculoskeletal radiologists and reviewed by the senior author. According to the algorithm we considered the presence of three or more threshold-level variables as a "positive" result, meaning the patient was predicted to have an adjacent infection. Comparing against the gold standard of MRI, the algorithm's accuracy was evaluated in terms of sensitivity, specificity, positive predictive value, and negative predictive value. In the new population, the sensitivity and specificity of the algorithm were 86% (95% CI, 0.70-0.95) and 85% (95% CI, 0.64-0.97), respectively. The positive predictive value was determined to be 91% (95% CI, 0.78-0.97), with a negative predictive value of 77% (95% CI, 0.61-0.89). All patients meeting four or more algorithm criteria were found to have septic arthritis with adjacent infection on MRI. Critical to the clinical applicability of the above-mentioned algorithm was its validation on a separate population different from the one from which it was built. In this study, the algorithm showed reproducible predictive power when tested on a new population. This model potentially can serve as a useful tool to guide patient risk stratification when determining the likelihood of adjacent infection and need of MRI. This better-informed clinical judgement regarding the need for MRI may yield improvements in patient outcomes, resource allocation, and cost. Level II, diagnostic study.

Efficacy of arthroscopic treatment for resolving infection in septic arthritis of native joints

BackgroundSeptic arthritis is a diagnostic and therapeutic emergency that threatens both life and function. The primary objective of this study was to assess the efficacy on the infectious process of arthroscopic treatment in patients with septic arthritis of native joints. The secondary objective was to identify factors predicting failure to achieve infection resolution after arthroscopic treatment. We hypothesised that arthroscopy was the appropriate treatment strategy. Material and methodsForty-six cases of septic arthritis in 46 patients with a mean age of 46 years (range, 18–72 years) were retrospectively reviewed. The cause of the septic arthritis was haematogenous dissemination in 39.1% of patients, surgery in 34.8%, a local injection in 19.6%, and trauma in 6.5%. The involved joint was the knee in 32 patients, the shoulder in 6, the hip in 3, the ankle in 3, and the elbow in 2. All patients underwent arthroscopic joint lavage, with or without synovectomy depending on the Gächter stage. Dual antibiotic therapy was given routinely after the procedure. For each patient, we assessed time to treatment, intraoperative findings according to the Gächter classification, cultures of drainage-fluids, and whether repeat arthroscopic lavage was required. Recovery of the infection was defined as absence of clinical or laboratory signs of infection at last follow-up. ResultsMean follow-up was 42 months (range, 1–120). Mean time from symptom onset to arthroscopic treatment was 7.5 days. Full recovery of the infection was achieved in 93% of patients, although 25% required more than one arthroscopic lavage. Factors significantly associated with arthroscopic treatment failure were Gächter stage III or IV and positive drainage-fluid cultures after 24h. ConclusionArthroscopic treatment is indicated in all patients with septic arthritis on native joints. The procedure should be repeated if the initial course is unfavourable. Level of evidenceIV. Retrospective study.

Neonatal TMJ ankylosis as a complication of septic arthritis infection

Neonatal TMJ ankylosis as a complication of septic arthritis infection

Invasive Polyarticular Septic Arthritis Caused by Nontypeable Haemophilus influenzae in a Young Adult

Nontypeable Haemophilus influenzae is a rare cause of septic arthritis in adults and has been reported to be associated with underlying medical conditions. We present a case of nontypeable H. influenzae-infected severe invasive polyarticular septic arthritis in a young adult without any underlying predisposing medical conditions. Diagnosis was made from both positive blood culture and joint aspiration culture. The patient was successfully treated with employment of aggressive surgical debridement of multiple affected septic joints as well as prolonged antibiotic treatment. Further laboratory testing did not reveal significant underlying medical conditions including negative HIV, normal levels of complement and IgG subclasses, and normal-appearing spleen on computed tomography. This case illustrates that nontypeable H. influenzae can cause serious invasive septic arthritis infection in both patients with and without predisposing underlying medical conditions and that prompt diagnosis with aggressive treatment of combined surgical and medical treatment can result in optimal recovery.

Does negative microscopy mean no infection in septic arthritis?

Does negative microscopy mean no infection in septic arthritis?

Infective arthritis secondary to bladder outflow obstruction

We describe two cases of septic arthritis occurring in association with lower urinary tract infection in elderly men. In both cases the organism isolated from both the joint and the urine was Staphylococcus aureus. Further investigation of the urinary tract in both individuals identified bladder outflow obstruction secondary to benign prostatic hyperplasia predisposing them to infection. The urinary tract should be suspected as a focus of infection in septic arthritis in elderly men and further investigation of the urinary system may disclose a surgically correctable lesion.