Category: potw

Paper of the week: Labeled white blood cell/bone marrow single-photon emission computed tomography with computed tomography fails in diagnosing chronic periprosthetic shoulder joint infection. Falstie-Jensen T, Daugaard H, Søballe K, Ovesen J, Arveschoug AK, Lange J; ROSA study group. J Shoulder Elbow Surg. 2019 Jan 31. pii: S1058-2746(18)30782-1. doi: 10.1016/j.jse.2018.10.024.

Summary by Dr. Sreeram Penna

This prospective cohort study assessed the diagnostic accuracy of combined labeled leukocyte (WBC) and technetium 99m sulfur colloid bone marrow imaging (WBC/BM) single-photon emission computed tomography-computed tomography in chronic shoulder prosthetic joint infection (PJI). Researchers reviewed patients with a failed shoulder arthroplasty, which was defined as any unsatisfactory result of any cause. Researchers considered shoulder infected if 3 positive tissue cultures with the same bacteria or if a sinus tract communicating to the prosthesis was present. The final cohort of 29 patients was included in the study. Of these 11 were considered positive based on infection definition criteria used. Only 2 patients in the infected group had positive WBC/BM single-photon emission computed tomography (2/11, 18.2%). There were no false positive cases in the study. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of detecting chronic shoulder PJI using this test was 0.18, 1.00, 1.00, 0.67, and 0.69 respectively. Although the study had a low sample size it has shown a lack of utility of bone scan in improving the diagnostic accuracy of chronic shoulder PJI.

Paper of the week: The Timing of Corticosteroid Injections After Arthroscopic Shoulder Procedures Affects Postoperative Infection Risk. Kew ME, Cancienne JM, Christensen JE, Werner BC. Am J Sports Med. 2019 Feb 13:363546518825348. doi: 10.1177/0363546518825348.

Commentary by Thema A. Nicholson MS, Surena Namdari MD

Arthroscopic shoulder surgery is exceedingly common and results in reliable pain relief and functional restoration. Unfortunately, there is a subset of patients that have pain or stiffness following shoulder arthroscopy that affects the quality of life and ability to participate in rehabilitation. A corticosteroid injection may be considered in these patients; however, the benefits of improved pain must be balanced by the risks of infection and/or poor tissue healing. This study sought to establish whether or not corticosteroid injections after arthroscopic surgery are a safe option to provide pain relief without predisposing patients to infection. A query of private payer and Medicare databases yielded 3946 patients that underwent an injection within 4 months after arthroscopic shoulder surgery. Patients who underwent an injection within 1 month after arthroscopic shoulder surgery had a 3.5% infection rate compared to a ≤0.5% infection rate in patients who underwent an injection at 2, 3 or 4 months. While data from large national databases can be flawed in many ways, this study supports our current practice of avoiding corticosteroid injections in the early postoperative period after shoulder arthroscopy. The influence of injections on tissue healing remains unknown.

Paper of the week: Orthopedic Implant-Associated Infection by Multidrug Resistant Enterobacteriaceae. Pfang BG, García-Cañete J, García-Lasheras J, Blanco A, Auñón Á, Parron-Cambero R, Macías-Valcayo A, Esteban J. J Clin Med. 2019 Feb 8;8(2). pii: E220. doi: 10.3390/jcm8020220.

Summary and Editorial by Sreeram Penna

This is a retrospective observational study from a single institution. Researchers reviewed all cases of orthopaedic implant-associated multidrug-resistant Enterobacteriaceae (MDREB). The overall incidence of MDREB was 6.4% (31/482). Six patients were excluded, and twenty-five patients are included in the study. Patients included ten prosthetic joints, seven osteosyntheses, six combination of prosthetic joint and osteosynthesis, and two spacers. MDREB is defined as any enterobacteria resistant to three or more antibacterial classes. Bacteria in this cohort was 12 extended spectrum beta-lactamase producing Escherichia coli, 3 OXA-48-carbapenamase producing Klebsiella pneumoniae, nine extended-spectrum beta-lactamase producing Proteus mirabilis and ten cases were polymicrobial infections. Overall 16 patients (64%) underwent implant removal. This included 7 cases of resection arthroplasty and 3 cases of Amputation. All patients with implant removal achieved 100% infection clearance. Only 33% of patients with retained implants had infection clearance. Four patients died within one year of diagnosis.

Literature review shows an increase in multidrug-resistant Gram-negative bacterial joint infections.[1] These multidrug-resistant Gram-negative bacterial infections are often difficult to control and require special antibiotics combinations to treat and also to prevent further development of antibiotic resistance.[2] Surgical procedures require implant removal for infection clearance.[3] This study provides further insights into MDREB orthopaedic implant infections and clearly shows how dangerous these are.

References

[1] Murillo O, Grau I, Lora-Tamayo J, Gomez-Junyent J, Ribera A, Tubau F, et al. The changing epidemiology of bacteraemic osteoarticular infections in the early 21st century. Clin Microbiol Infect 2015;21:254.e1-8. doi:10.1016/j.cmi.2014.09.007.
[2] Hawkey PM, Warren RE, Livermore DM, McNulty CAM, Enoch DA, Otter JA, et al. Treatment of infections caused by multidrug-resistant Gram-negative bacteria: report of the British Society for Antimicrobial Chemotherapy/Healthcare Infection Society/British Infection Association Joint Working Party. J Antimicrob Chemother 2018;73:iii2–78. doi:10.1093/jac/dky027.
[3] Papadopoulos A, Ribera A, Mavrogenis AF, Rodriguez-Pardo D, Bonnet E, Salles MJ, et al. Multidrug-resistant and extensively drug-resistant Gram-negative prosthetic joint infections: Role of surgery and impact of colistin administration. Int J Antimicrob Agents 2018. doi:10.1016/j.ijantimicag.2018.10.018.

Paper of the week: In vivo analysis of a first-in-class tri-alkyl norspermidine-biaryl antibiotic in an active release coating to reduce the risk of implant-related infection. Williams DL, Epperson RT, Ashton NN, Taylor NB, Kawaguchi B, Olsen RE, Haussener TJ, Sebahar PR, Allyn G, Looper RE. Acta Biomater. 2019 Jan 31. pii: S1742-7061(19)30077-7. doi: 10.1016/j.actbio.2019.01.055.

Summary and Editorial by Sreeram Penna

This study in a sheep model of joint space infection was conducted to assess antibacterial properties of compound CZ-01127 as the active release agent in a silicone (Si)-based implant coating to prevent periprosthetic joint infection. Researchers also studied the impact of silicone-based coating and compound CZ-01127 on bone ingrowth and integration. Bone ingrowth was studied using implanting simulated total joint replacement device with regions of porous-coated titanium and adjacent silicone polymer with and without CZ-01127. To understand ability of CZ-01127 to reduce bioburden total joint replacement devices with a silicon-based coating with the above compound was used and compared against controls without compound. And sheep were inoculated with bacteria (MRSA) during implantation procedure after that sheep was monitored to assess outcome, especially infection.

Results of the study show that the CZ-01127 coating reduced bioburden near the total joint replacement device. It also appeared to provide some protection to the joint space and synovium. However joint space ultimately succumbed and was susceptible to infection following bacterial challenge. Bone ingrowth assessment showed that both Titanium and Silicone coated surfaces had decent osseointegration at 24 weeks post procedure. Coating with CZ-01127 resulted in initial bone resorption followed by regrowth, remodeling, and recovery by 8 weeks.

Implant-related infection is associated with significant morbidity and mortality.[1] To prevent this costly complication various methods are actively researched one of this is the development of active release coatings to implants that reduce bioburden and inhibit biofilm production.[2] Antibiotics are considered as compounds for active release. However, researchers in this study identified concerns using antibiotics as it is noted that these coatings loose activity over time and there is concern over the development of antibiotic resistance due to subminimum inhibitory concentrations reached at the site of implants. They suggested using novel substances which reduce the risk of resistance. Researchers identified CZ compounds as they have broad-spectrum activity against planktonic and biofilm bacteria.[3–5] This study assesses the use of newer compound CZ-01127 with silicone polymer to create an effective active release implant to combat implant-related infection.

References

[1]   Parvizi J, Zmistowski B, Adeli B. Periprosthetic joint infection: treatment options. Orthopedics 2010;33:659. doi:10.3928/01477447-20100722-42.
[2]   Hetrick EM, Schoenfisch MH. Reducing implant-related infections: active release strategies. Chem Soc Rev 2006;35:780–9. doi:10.1039/b515219b.
[3]   Haussener TJ, Sebahar PR, Reddy HRK, Williams DL, Looper RE. A practical synthesis of N-alkyl- and N,N′-dialkyl-polyamines This work is dedicated to the memory of our dear colleague and friend Mr. Charles Edward Price. Tetrahedron Letters 2016;57:2845–8. doi:10.1016/j.tetlet.2016.05.034.
[4]   Looper R, Williams D, Jeyapalina S, Haussener T, Sebahar PR, Reddy HK. Compositions comprising a biocidal polyamine. US8853278B1, 2014.
[5]   Williams D, Looper R, Jeyapalina S, Haussener T, Sebahar PR, Reddy HK. Methods of use for compositions comprising a biocidal polyamine. US9034927B2, 2015.