Prospective Clinical Trial for Septic Arthritis: Cartilage Degradation and Inflammation Are Associated with Upregulation of Cartilage Metabolites

Needle arthroscopy in the surgical management of septic arthritis of the shoulder joint in neonates and infants

Septic arthritis in neonates and infants is a life-threatening condition which should be treated promptly to reduce morbidity and mortality. The chondrolytic effect of bacteria and proteolytic enzymes is well documented. Surgical management consists of repeated needle aspirations in one sitting, arthroscopic washout or arthrotomy for open washout. In very small children, it is difficult to perform arthroscopy using conventional endoscopes. Arthrotomies carry significant risks including iatrogenic injury to the key structures given the small size of patients. It can also leave unsightly scars and the approach to the joint can be challenging. We present two cases of shoulder septic arthritis managed successfully using needle arthroscopy. This technique involves a 1.9 mm Arthrex 'NanoNeedle Scope' (Naples, Fl, USA) in a 2.3 mm cannula. A second portal can be used for joint sampling, debridement and irrigation outflow. Both children recovered with no repeated washouts necessary and excellent clinical results at an average follow-up of one year.

Prior Septic Arthritis Within One Year of Knee Arthroplasty is Associated With a High Risk for Infection

BACKGROUND

A prior history of a septic knee may predispose patients to a periprosthetic joint infection (PJI) after total knee arthroplasty (TKA). We performed multivariate analyses of known risk factors that portend a periprosthetic infection for patients who have a history of septic arthritis (SA). The focus of the study was an assessment of the incidence of TKA PJIs at various time intervals after the onset of a septic knee (0 to 3 months, 3 to 6 months, 6 to 9 months, and 9 months to 1-year).

METHODS

We queried a national database to identify patients who underwent a primary TKA between 2010 and 2021 (n = 1.9 million). Patients who had a prior septic knee ipsilateral to the primary TKA were characterized (n = 4,251) and were put into four specific cohorts based on the interval between the SA diagnosis and TKA: less than 3 months; 3 to 6 months; 6 to 9 months; and 9 to 12 months. A cohort of patients who did not have history of septic knee were used for comparison (n = 5,000). The incidence of PJIs from 90 days to 1 year was identified and compared using multivariate analyses.

RESULTS

All time cohorts were more likely to require revisions due to PJI, as compared to the comparison group. Significant differences were demonstrated among all time cohorts who had prior SA compared to patients who did not have a history of SA (odds ratio [OR] range, 90.0 to 113.0, P < .001).

CONCLUSION

This study has shown an increased PJI risk in the first year after SA (P < .05). The surgeon should be aware of the increased PJI risk after SA within the first year after TKA.

Arthroscopic Treatment Yields Lower Reoperation Rates than Open Treatment for Native Knee but Not Native Shoulder Septic Arthritis

Purpose

To compare the incidence, patient demographics, complication rates, readmission rates, and reoperation rates of open and arthroscopic surgery performed for septic arthritis in native knee and shoulder joints.

Methods

Records of patients who were diagnosed with native knee or shoulder septic arthritis and underwent open or arthroscopic irrigation and debridement (I&D) between 2015 and 2018 were queried from the PearlDiver Mariner Database. International Classification of Diseases 10th (ICD-10) diagnosis and procedure codes were used to identify patients and track reoperations. Reoperation procedures, including revision open and arthroscopic I&D, were analyzed at 1 month, 1 year, and 2 years. Complications, emergency department (ED) admissions, and hospital readmissions within 30 days were analyzed and compared between the open and arthroscopic cohorts.

Results

The query resulted with 1,993 patients who underwent knee I&D (75.3% arthroscopic, 24.7% open, P < .001) and 476 patients who underwent shoulder I&D (64.8% arthroscopic, 35.2% open, P < .001). One-month complication rates (11.6-22.7%) and hospital readmission rates (15.8-19.6%) were similar for arthroscopic and open treatment for knee and shoulder septic arthritis. Reoperation rates for revision I&D of the knee were higher after open compared to arthroscopic treatment at 1 month, 1 and 2 years (20.9% vs. 16.7%, 32.5% vs 27.6% and 34.1% vs. 29.4%, P < .05, respectively). For shoulder septic arthritis 1-month, 1-year, and 2-year reoperation rates were similar for open and arthroscopic treatment (16.0% vs 11.7%, 22.0% vs 19.3%, and 22.7% vs 20.0%, P = .57, respectively). Lastly, 6.7% of patients with native septic knee arthritis underwent subsequent arthroplasty by 2 years.

Conclusion

Arthroscopic treatment carries a lower reoperation rate than open surgery for knee septic arthritis, but in the shoulder, the risk for revision I&D is similar after arthroscopic or open surgery.

The Use of Biomarkers in the Early Diagnosis of Septic Arthritis and Osteomyelitis-A Pilot Study

BACKGROUND

The diagnosis of septic arthritis (SA) and osteomyelitis (OM) has remained challenging in the pediatric population, often accompanied by delays and requiring invasive interventions. The purpose of this pilot study is to identify a novel panel of biomarkers and cytokines that can accurately differentiate SA and OM at initial presentation using serum alone.

METHODS

Twenty patients below 18 years old whose working diagnosis included SA (n=10) and OM (n=10) were identified. Serum was collected at initial evaluation. Each sample underwent seven ELISA [C1-C2, COMP, CS-846, hyaluronan, procalcitonin, PIIANP, C-terminal telopeptide of type II collagen (CTX-II)] and 65-plex cytokine panels. Principal component and Lasso regression analysis were performed to identify a limited set of predictive biomarkers.

RESULTS

Mean age was 4.7 and 9.5 years in SA and OM patients, respectively (P=0.029). 50% of SA patients presented within 24 hours of symptom onset, compared with 0% of OM patients (P=0.033). 30% of SA patients were discharged home with an incorrect diagnosis and re-presented to the emergency department days later. At time of presentation: temperature ≥38.5°C was present in 10% of SA and 40% of OM patients (P=0.12), mean erythrocyte sedimentation rate (mm/h) was 51.6 in SA and 44.9 in OM patients (P=0.63), mean C-reactive protein (mg/dL) was 55.8 in SA and 71.8 in OM patients (P=0.53), and mean white blood cells (K/mm3) was 12.5 in SA and 10.4 in OM patients (P=0.34). 90% of SA patients presented with ≤2 of the Kocher criteria. 100% of SA and 40% of OM patients underwent surgery. 70% of SA cultures were culture negative, 10% MSSA, 10% Kingella, and 10% Strep pyogenes. 40% of OM cultures were culture negative, 50% MSSA, and 10% MRSA. Four biomarkers [CTx-II, transforming growth factor alpha (TGF-α), monocyte chemoattractant protein 1 (MCP-1), B cell-attracting chemokine 1] were identified that were able to classify and differentiate 18 of the 20 SA and OM cases correctly, with 90% sensitivity and 80% specificity.

CONCLUSIONS

This pilot study identifies a panel of biomarkers that can differentiate between SA and OM at initial presentation using serum alone.

LEVEL OF EVIDENCE

Level II-diagnostic study.

Novel anti-inflammatory and chondroprotective effects of the human melanocortin MC1 receptor agonist BMS-470539 dihydrochloride and human melanocortin MC3 receptor agonist PG-990 on lipopolysaccharide activated chondrocytes

Human melanocortin MC1 and MC3 receptors expressed on C-20/A4 chondrocytes exhibit chondroprotective and anti-inflammatory effects when activated by melanocortin peptides. Nearly 9 million people in the UK suffer from osteoarthritis, and bacterial infections play a role in its development. Here, we evaluate the effect of a panel of melanocortin peptides with different selectivity for human melanocortin MC1 (α-MSH, BMS-470539 dihydrochloride) and MC3 ([DTrp⁸]-γ-MSH, PG-990) receptors and C-terminal peptide α-MSH_11-13(KPV), on inhibiting LPS-induced chondrocyte death, pro-inflammatory mediators and induction of anti-inflammatory proteins. C-20/A4 chondrocytes were treated with a panel of melanocortin peptides prophylactically and therapeutically in presence of LPS (0.1 μg/ml). The chondroprotective properties of these peptides determined by cell viability assay, RT-PCR, ELISA for detection of changes in inflammatory markers (IL-6, IL-8 and MMP-1, -3 and -13) and western blotting for expression of the anti-inflammatory protein heme-oxygenase-1. C-20/A4 expressed human melanocortin MC1 and MC3 receptors and melanocortin peptides elevated cAMP. LPS stimulation caused a reduction in C-20/A4 viability, attenuated by the human melanocortin MC1 receptor agonist BMS-470539 dihydrochloride, and MC3 receptor agonists PG-990 and [DTrp⁸]-γ-MSH. Prophylactic and therapeutic regimes of [DTrp⁸]-γ-MSH significantly inhibited LPS-induced modulation of cartilage-damaging IL-6, IL-8, MMPs -1,-3 and -13 mediators both prophylactically and therapeutically, whilst human melanocortin MC1 and MC3 receptor agonists promoted an increase in HO-1 production. In the presence of LPS, activation of human melanocortin MC1 and MC3 receptors provided potent chondroprotection, upregulation of anti-inflammatory proteins and downregulation of inflammatory and proteolytic mediators involved in cartilage degradation, suggesting a new avenue for osteoarthritis treatment.

Type II collagen peptide Coll2-1 is an actor of synovitis

OBJECTIVE

We evaluated the ability of Coll2-1, a type II collagen peptide, to activate pro-inflammatory pathways in synovial cells and to induce arthritis in Lewis rats.

METHOD

Human synoviocytes and chondrocytes from knee OA patients were cultured for 24 h with/without Coll2-1 and/or purified immunoglobulin G (AS0619) binding specifically this peptide, and/or CLI-095, a TLR-4 signaling inhibitor and/or apocynin and diphenyleneiodonium, Reactive oxygen species (ROS) production inhibitors. The Interleukin (IL)-8 and Vascular Endothelium Growth Factor (VEGF) expression, the IL-8 production, the IκB-α and p65 phosphorylation and ROS were evaluated. Coll2-1 peptide, bovine type II collagen (CIA), streptococcal cell wall (SCW) or saline solution were injected into Lewis rats. The Coll2-1 peptide was injected subcutaneously (SC; 20-200μg/100μl/animal) or intra-articularly (IA; 0.5-5μg/50μl/animal) and compared to CIA injected in SC (200μg/100μl/animal) and SCW in IA (5μg/50μl/animal). The animals were injected on day 0 and monitored for 28 days. Histological lesions assessment was performed using an arthritis score.

RESULTS

Coll2-1 peptide significantly increased IL-8 gene expression and production by synoviocytes. AS0619 and CLI-095 significantly decreased IL-8 expression. Coll2-1 induced p65 and IκBα phosphorylation and oxidative stress inhibitors decreased it. In human chondrocytes culture, Coll2-1 significantly increased MMP-3 and VEGF gene expression. In Lewis rats, CIA, SCW or Coll2-1 injection triggered arthritis. Like CIA or SCW, Coll2-1 induced synovitis, loss of cartilage proteoglycans, cartilage structure lesion and subchondral bone remodeling.

CONCLUSIONS

Coll2-1 activates synoviocytes to produce IL-8 and induces arthritis in rat. These findings suggest that neutralizing Coll2-1 could be a therapeutic approach of arthritis.