enterobacteria resistance to the class of antibiotics called carbepenems
Who are enterobacteriaceae?
Large group of gram negative rods that inhabit human large intestine, soil, plants, and water.
They grow equally well in air (aerobic) and without air (anerobic).
Most common enterobacteri that are found in hospitalized patients and causing disease are:
eschericia coli, Enterobacter cloacae, Klebsiella pneumonia, Serratia marcesens, and roteus mirailis.
Enterobacteriacae rarely infect patients that are not immunocompromised. Which means the host defenses must be breached in order to cause infection therefore illness.
How does this occur? surgery, IVs, tube feedings, burns, ulcers, breaks in the skin, and contaminated food or beverages.
Enterobacteriacae can be resistant to first generation cephalosporins such as cefazolin and cephalexin. Cephalosporins work by killing bacterial cells by imparie cell wall synthesis. This is done by preventing the cross-binding of the peptoglycan polymers neecessary for cell wall formtion. The most comon form of antibiotic resistance from enterobacteria are the production of beta lactimase which can destroy the beta lactam ring by hydrolysis therefore prevent antimicrobial activity. Theses are known as the ESBL's.
They are a common source of infections in the hospitalized patient. Repeated use of antibiotic drug specific to the infection, and empirical Use before culutres are done) use have cause these enterobacteriaceae in some patients to become very resistant to treatment.
What are carbepenems?
They interfere with cell wall synthesis by pinding to penicillin-binding proteins (PBPs) enzymes which are essential for cell wall synthesis
Spectrum of activity;
It is due to the PBPs of bothe gram negative and gram positive bacteria.
Carbepenes are: Imipenem, merepenem, ertapenem
Why is there a concern with this class of medications?
Enterobacteriaceae are now becoming resistant to this class of drugs.
This is our last line of defense against infections in some patients. There is no other treatment.
Pharmaceutical companies are not investing time and money into antibiotics becasue resistance occurs faster than drugs are worked on.
So how to we prevent the spread of these resitant enterobacteriaceae?
Hand hygiene.
Contact precautions
Dr. Carnelli from Tel Aviv Hospital, Tel Aviv, Isreal is an epidemiologist working their. They had an outbreak several year ago. He had 2 patient floors set aside for CPC patient. He halso had dedicated staff to those floors . Which means the staff did not work anywhere else in the hosptal. Equipment did not leave the floor. There were special exceptions: such as the patient who needed ICU care. It took about 2 weeks for nonew cases of CPC to develop. (The did genotyping on all the CPC detected). The hospital remained CPC free for about 6 months. Dr, Carnelli then looked at where the patients were coming from. Those patients coming from skilled facilities where their exposure to the healthcare system was higher, had a high incidence of CPC. Therefore every patient entering Tel Aviv hospital is now screened for CPC.
At the kindred hospital where I work and our sister site, patient who develop CPC are placed in a private room, with very strict precautions.
web sites visitied for this article:
Http//:emergency.cdc.gov/cocoa/summaries/pdf/CarbepenemResistantEnterobac1709.interim.pdf
Htt//:www.aic.cuhk.edu.hk/web8/carbepenems.htm
http//:lib.bioinfo.pl/meid.23481
Kindred Hospital Antibiotic Stewardship Program
APIC Text for Infection Control: Volume II Scientific and Practice Elements
Yehuda Carmeli,MD, MPH, Chief of Epidemiology Tel AViv Sourasky Medical Center Tel Aviv, Israel, Research staff member Beth Israel Deaconess Medical Center,Boston, Ma lecture given 3/15/2010
Kenneth Lawrence, PharmD
Clinical Pharmacy Specialist - Infectious Diseases, Tufts Medical Center, Boston, Ma
Assistant Professor of MEdicine, Tufts University School of Medicine, Boston, Ma lecture given 3/15/2010
Antibiotic-Resistant Bugs in the 21st Century - A Clinical SUper-Challenge. New ENgland Journal of Medicine 360;5 January 29, 2009 pages 439-443
by Cesar Arias, MD, PhD, and Barbara Murray, MD
ored contantly and explore wayshow they can positively impact public health.
