Device-related infections

Habash M, Reid G. Microbial biofilms their development and significance for medical device-related infections. Journal of Clinical Pharmacology 1999, 39, 887-898. 

Switching from intravenous to oral antibiotics should be considered as soon as clinically appropriate. Prolonged intravenous therapy is associated with risk of intravascular device-related infection and delays discharge. Indicators for switch include resolution of fever, tachycardia, tachypnoea, hypotension and hypoxia and the patient should be clinically hydrated with good oral intake and no gastrointestinal absorption concerns. 

The use is discussed of antimicrobial coatings for medical devices to reduce the occurrence of device-related infections. Antimicrobial coatings provide a low cost... 

The predominant mechanism of biofilm accumulation in staphylococci involves polysaccharide intercellular adhesin (PIA) [60-66], S. epidermidis strains lacking this adhesin are also regularly isolated from biomaterial-related infections, a fact which prompted a search for an alternative, PIA-independent accumulation mechanism [51, 52, 60-62, 67, 68], The responsible molecule was identified as accumulation associated protein, Aap [69-71], and there may also be a role for additional proteinaceous intercellular adhesins [52], Aap has a similar-acting homolog, SasG, in S. aureus [72], adding to the accumulating evidence that proteinaceous intercellular adhesins are also of importance in S. aureus biofilm formation and device-related infection [52, 72-74],... 

P. Stoodley, L. Hall-Stoodley, B. Costerton, P. DeMeo, M. Shirtliff, E. Gawalt, S. Kathju, Biofilms, biomaterials, and device-related infections, in B.D. Ratner, A.S. Hoffman, FJ. Schoen, J.E. Lemons (Eds.), Biomaterial Science Introduction to Materials in Medicine, third ed.. Academic Press, Elsevier, Waltham, MA, USA, 2013. 

Baddour LM, Bettmann MA, Bolger AF et al (2003) Non-valvular cardiovascular device-related infections. AHA scientific statement. Circulation 108 2015-2031... 

Bracke FA, Meijer A, Van Gelder LM (2004) Lead extraction for device related infections a single centre experience. Europace 6 243-247... 

Fig 7 7 Diagnostic strategy in suspected cardiac-device-related infective endocarditis (CDRIE). CT, computed tomography ICE, intracardiac echocardiography IE, infective endocarditis TEE, tran-soesophageal echocardiography, TTE, transthoracic echocardiography... 

Some authors recommend contralateral reimplantation as early as 36 h after extraction in patients with local symptoms only of device-related infection [10]. In some instances, it is considered safe to perform a contralateral same-day reimplantation [11]. The reasons for a same-day reimplantation are usually pacemaker (PM) dependency or hemodynamic need for CRT in case of biventricular pacing. In fact, the risk of subsequent CIED infections and venous thrombosis increases while maintaining a transvenous temporary device, and for this reason, it cannot be used indefinitely [12]. Same-day reimplantation is considered safe if the patient is clinically proven not to have active systemic bacteremia or infection by blood culture at the time of extraction and there is a lack of transesophageal echocardiographic evidence for endocarditis and the presence of a normal white blood cell count. 

Pearson, M. L., Guideline for prevention of intravascular device-related infections. Part 1. Intravascular device-related infections An overview. Part II. Recommendations for the prevention of nosocomial intravascular device-related infections, Am. J. Infect. Control, 1996 24(4) 262-293. 

There are other areas where opportunities exist to improve allograft and xenograft performance. For example, device-related infections are a costly complication in soft tissue repair procedures such as abdominal wall repair. The local delivery of antibiotics may reduce postsurgical infections. The TYRX mesh now marketed by Medtronic/ Covidien delivers antibiotics to the subcutaneous pocket following implantation of a pacing device. The incorporation of antibiotics or other antimicrobial agents such as lysostaphin, as by Stishkumar et al., may represent an innovative approach to infection control particularly in contaminated and infected wounds. 

Biofilms have great importance for public health because of their role in certain infectious diseases and their role in a variety of device-related infections. Biofilm infections on indwelling devices or implants are difficult to eradicate because of their much better protection against macrophages and antibiotics, compared to free living cells, leading to severe clinical complications often with lethal outcome. 

Francolini I, Donelh G. Prevention and control of biofilm based medical device related infections. FEMS Immunol Med Microbiol 2010 59 227-38. 

Khardoii N, Yassien M. Biofilms in device-related infections. J Ind Microbiol 1995 15 141-7. 

Hogan S, Stevens NT, Humphreys H, O Gara JP, O Neill E. Current and future approaches to the prevention and treatment of staphylococcal medical device-related infections. Curr Pharm Des 2015 21 100-13. 

The last method of prevention represents one of the most promising strategies developed in recent years since the antimicrobial agent adsorbed on the catheters is released directly at the infection site. Recently, inhinsicaUy antimicrobial polymers have emerged as promising candidates to address biofilm-based medical device-related infections. 

This chapter will be focused on antimicrobial PUs for intravascular applications. First, a classification of the types of PU intravascular devices and their impact in the medical held will be inhoduced. Then, a survey of infections associated with intravascular devices in terms of incidence, etiology, and pathogenesis will be presented. Next, management of device-related infections and the role of modified PUs in preventing intravascular device-related infections will be discussed. Finally, the future direction of novel antimicrobial polymers as biomaterials for the development of devices preventing biofilm-based infections will be described. 

Microrganisms involved in intravascular device-related infections... 

An increasing proportion of inhavascular device-related infections are being caused by Candida spp. and the management of these infections can be challenging. Candida infections account for ca. 10% of the whole number of intravascular catheter-associated infections. Usually the management of these infections requires the device removal. 

In the following sections, antifouling and antimicrobial PUs will be presented in relation to their application for preventing intravascular device-related infections. 

A crucial feature required for a successful application of PUs as biomaterials is their ability to prevent microbial colonization. Indeed, any implanted biomaterial is known to have the potential to put the patient at high risk of infection. In case of intravascular devices, the development of device-related infections may result in life-threatening consequences for the patient. 

Dmg-releasing PUs can be considered the first milestone in the prevention of intravascular device-related infections. Already, their clinical application has contributed to decreasing infection risk, mortality rate, and patient morbidity. However, the use of these drag-releasing polymers has elicited concerns in terms of durability and possible local emergence of resistant microorganisms. 

Nery PB, Fernandes R, Nair GM, et al. Device-related infection among patients with pacemakers and implantable defibrillators incidence, risk factors, and consequences. J Cardiovasc Electrophysiol July 2010 21(7) 786-90. 

Maniar S, Kondareddy S, Topkara VK. Left ventricular assist device-related infections past, present and future. Expert Rev Med Devices September 2011 8(5) 627-34. 

O Grady NP, Alexander M, Bums LA, et al. Guidelines for the prevention of intravascular catheter-related infections. Am J Infect Control May 2011 39(4 Suppl. l) Sl-34. Francolini 1, Donelli G. Prevention and control of biofilm-based medical-device-related infections. FEMS Immunol Med Microbiol August 2010 59(3) 227-38. 

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