Germ of the Month - September 2005

This month we would like to introduce you to Elliot (Staphylococcus epidermidis). Like so many of our germie family, as long as he stays where he belongs, he’s such an asset to our lives. S. epidermidis serves to crowd the skin as a protective bacteria so that other bacteria, including those with significant adverse sequelae cannot get on board. Additionally, they also help us to slough our dry skin, allowing newer layers to surface, a constantly ongoing process. But increasingly, Elliott has been sneaking into places he doesn’t belong!

While at one time the appearance of S. epidermidis in clinical material could be dismissed as contamination, it is now one of the most important agents of hospital acquired infections.¹ Also known as coagulase negative staphylococci, S. epidermidis is a common cause of nosocomial bacteraemia. S. epidermidis is normally resident in the skin flora, the gut and upper respiratory tract. It is a true opportunistic pathogen, requiring a major breach in the host's protective systems to establish infection.² S. epidermidis is often associated with indwelling catheters and prosthetic materials, valves used to treat hydrocephalus, prosthetic heart valves, IV lines, intraperitoneal catheters and orthopaedic prostheses. It is a major cause of bacteraemia in neutropenics and in all infections there is a risk of endocarditis, particularly prosthetic valve
endocarditis. S. epidermidis, the most common CoNS pathogen, accounts for about 74% to 92% of all hospital-acquired CoNS infections³ and is a common agent in peritonitis as a consequence of continuous ambulatory peritoneal dialysis (CAPD).⁴ It is also a serious neonatal infection, particularly in very low birth weight infants.⁵

Its high recurrence rate may be related to its propensity to form a biofilm layer which coats the bacteria and protects by engulfment or by neutrophils⁶. This slime layer, or biofilm, may make antibiotic penetration and bacteria eradication more difficult. S. epidermidis treatment may require removal of line or prosthesis.⁷ About 50% of CoNS are resistant to methicillin, with high frequencies (80%) in the case of S. epidermidis. These infections are very serious and can even be fatal.⁸ The current antibiotic of choice is vancomycin.9 As always, a key component to the reduction of transmission is good hand hygiene with a product that has good persistence.

We hope you enjoy introducing your staff to Elliott this month as you continue your own efforts to educate and maintain awareness about infectious disease in your facility. This information is brought to you by Mölnlycke Health Care, maker of Hibiclens® antiseptic and Hibistat®, convenient antimicrobial towelettes with the persistence of CHG.⁹ Our reason for all that we do is to provide you with the very best in products and support, to help you control infections. We look forward to hearing from you about our Hibigeebie® campaign. Please feel free to contact us at 1-800-843-8497.

 

 

 

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1 Accessed at: http://medinfo.ufl.edu/year2/mmid/bms5300/bugs/staepid.html
2 Accessed at: http://www.surgical-tutor.org.uk
3 Martin MA, Pfaller MA, Wenzel RP. Coagulase-negative staphylococcal bacteremia. Mortality and hospital stay. Ann Intern Med 1989;110:9-16.
4 Dryden MS, Talsania H, Rodgers J, Bayston R, Phillips I. Serological response to coagulase-negative staphylococci in patients with peritonitis on continuous ambulatory peritoneal dialysis. Eur J Clin Microbiol Infect Dis 1993;12:87-92.
5 Bialkowska-Hobrzanska H, Jaskot D, Hammerberg O. Evaluation of restriction endonuclease fingerprinting of chromosomal DNA and plasmid profile analysis for characterization of multiresistant coagulase-negative staphylococci in bacteremia
neonates. J Clin Microbiol 1990;28;269-75.
6 Wheeless Textbook of Orthoapedics. Accessed at: http://www.wheelessonline.com/ortho/staph_epidermidis
7 Wheeless Textbook of Orthoapedics. Accessed at: http://www.wheelessonline.com/ortho/staph_epidermidis
8 Accessed at: http://medinfo.ufl.edu/year2/mmid/bms5300/bugs/staepid.html
9 Vannuffel P, Gigi J, Ezzedine H, et al. Specific detection of methicillin-resistant staphylococcus species by multiplex PCR. J Clin Microbiol 1995;33:2864-7.
9 Mölnlycke Health Care urges all users to read the product leaflet closely and use Hibi products only as directed.