Featured Research

from universities, journals, and other organizations

Development of two tests for rapid diagnosis of resistance to antibiotics

Date:
October 12, 2012
Source:
INSERM (Institut national de la santé et de la recherche médicale)
Summary:
Two new tests capable of rapidly diagnosing resistance to wide-spectrum antibiotics have just been developed. Thanks to these tests, it now takes only two hours to identify certain bacteria that are resistant to the most used and the most important antibiotics in hospitals. The main targeted bacteria are enterobacteriacae (such as E. Coli), that are responsible for infections.

Credit: Image courtesy of INSERM

Two new tests capable of rapidly diagnosing resistance to wide-spectrum antibiotics have just been developed by Inserm Unit 914 "Emerging resistances to antibiotics" (Bicêtre Hospital, Le Kremlin-Bicêtre) under the direction of Professor Patrice Nordmann. Thanks to these tests, it now takes only 2 hours to identify certain bacteria that are resistant to the most used and the most important antibiotics in hospitals. The main targeted bacteria are enterobacteriacae (such as E. Coli), that are responsible for infections. With their excellent sensitivity and specificity, the use of these extremely efficient tests on a world-wide scale would allow us to adapt antibiotic treatments to the individual's needs and to be more successful in controlling antibiotic resistance, particularly in hospitals.

Related Articles


These works were published in September in two international reviews: Emerging Infectious diseases and The Journal of Clinical Microbiology.

These diagnostic tests will allow rapid identification of certain bacteria that are resistant to antibiotics and hence: -- Allow us to better adapt the treatment to the infected patients -- Avoid the inappropriate use of certain antibiotics, thus avoiding the over-use of certain wide-spectrum antibiotics -- Isolate patients infected with these resistant bacteria and thus avoid the development of epidemics in hospitals

There is an ever-increasing number of emerging bacteria that cause cross-border epidemics. Researchers all agree on the fact that it is not the number of bacteria that is the problem, but their increasing resistance to antibiotics. The situation is particularly dramatic for certain species of bacteria, Gram-negative bacilli such as enterobacteriacae. (1)

A worrying situation both for banal infections and for major treatments

Whereas certain antibiotics such as wide-spectrum cephalosporins used to be reserved for the most serious cases, now there are cases where they are totally inactive against certain bacterial germs and consequently there is no effective antibiotic treatment for these. And so we are now faced with situations where the treatment of banal infection such as urinary or intra-abdominal infections has no effect. And this puts the life of the patients at risk. Every year, an estimated 25,000 deaths in Europe are due to multi-resistance to antibiotics.

Furthermore, the development of resistance to antibiotics affects an entire aspect of modern medicine that needs efficient antibiotics (grafts, transplants, major surgery, reanimation, etc.).

Undetected importation of multiresistant strains from foreign countries can also considerably accelerate the diffusion of this multiresistance phenomenon.

Two ultra-rapid tests: from Red to Yellow

In an attempt to slow down these increasing resistances, the Inserm researchers have developed a system that can rapidly detect the two enzymes responsible for causing resistance to the bacteria of two classes of common antibiotics: wide-spectrum cephalosprins and carpabenems. In these tests, the presence of an enzyme indicates the presence of a resistant bacteria.

These tests (Corba NP test and ESBL NDP test) are based on the acidification properties generated by the activity of the enzymes (ß-lactamases and carbapenemases) when they are in the presence of an antibiotic. If any one of these enzymes is present, the medium becomes acid and the acidity indicator (pH) turns from red to yellow.

At present, these tests can be performed using bacteria isolated from urine samples taken during a detected infection, or from bacteria present in stools. The result is obtained in less than 2 hours (compared to 24 to 72 hours using current techniques). These tests are highly sensitive and highly reliable (100%). They are totally inoffensive since they are carried out on bacteria isolated from patients or on biological products such as urine, etc.

Patrice Nordmann, Inserm Research Director and main author of this work, points out that "These tests are currently being assessed in order to ascertain their sensitivity directly from infected sites such as blood or urine."

The invention of these tests is an important breakthrough in the fight against the resistance to antibiotics. These tests will provide a simple, inexpensive (less than 4 to 5 euros) means of very rapidly detecting the most serious cases of resistance to antibiotics in human medicine and will contribute to limiting international diffusion.

As Patrice Normann states "We can hope, in particular in many Western countries where the situation has not yet reached endemic proportions multi-resistances (France, in particular), to be able to preserve to a certain extent the efficiency of wide-spectrum cephalosporins and carbapenems, antibiotics used as a "last resource."

Used straight at the patient's bedside, these tests will help us to optimise the use of antibiotic treatment, in particular in the developing countries where the levels of resistance are extremely high.

Two international patent applications have been filed with Insert Transfert. Their commercialisation is in the course of development and they should be available in about 12-16 months, however the techniques are available for any specialised laboratories who wish to develop them.

Footnote

(1) Enterobaceriacae, including E. coli, usualy infest the human intestine. Given their proximity to the urinary and digestive tracts, urinary and digestive infections due to these germs are the most frequent.


Story Source:

The above story is based on materials provided by INSERM (Institut national de la santé et de la recherche médicale). Note: Materials may be edited for content and length.


Journal References:

  1. Patrice Nordmann, Laurent Poirel, Laurent Dortet. Rapid Detection of Carbapenemase-producingEnterobacteriaceae. Emerging Infectious Diseases, 2012; 18 (9): 1503 DOI: 10.3201/eid1809.120355
  2. Patrice Nordmann, Laurent Dortet and Laurent Poirel. Rapid Detection of Extended-Spectrum-β-Lactamase-Producing Enterobacteriaceae. The Journal of Clinical Microbiology, 2012 DOI: 10.1128/%u200BJCM.00859-12

Cite This Page:

INSERM (Institut national de la santé et de la recherche médicale). "Development of two tests for rapid diagnosis of resistance to antibiotics." ScienceDaily. ScienceDaily, 12 October 2012. <www.sciencedaily.com/releases/2012/10/121012112420.htm>.
INSERM (Institut national de la santé et de la recherche médicale). (2012, October 12). Development of two tests for rapid diagnosis of resistance to antibiotics. ScienceDaily. Retrieved October 25, 2014 from www.sciencedaily.com/releases/2012/10/121012112420.htm
INSERM (Institut national de la santé et de la recherche médicale). "Development of two tests for rapid diagnosis of resistance to antibiotics." ScienceDaily. www.sciencedaily.com/releases/2012/10/121012112420.htm (accessed October 25, 2014).

Share This



More Plants & Animals News

Saturday, October 25, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Deep Sea 'mushroom' Could Be Early Branch on Tree of Life

Deep Sea 'mushroom' Could Be Early Branch on Tree of Life

Reuters - Innovations Video Online (Oct. 24, 2014) — Miniature deep sea animals discovered off the Australian coast almost three decades ago are puzzling scientists, who say the organisms have proved impossible to categorise. Academics at the Natural History of Denmark have appealed to the world scientific community for help, saying that further information on Dendrogramma enigmatica and Dendrogramma discoides could answer key evolutionary questions. Jim Drury has more. Video provided by Reuters
Powered by NewsLook.com
Black Bear Cub Goes Sunday Shopping

Black Bear Cub Goes Sunday Shopping

Reuters - Light News Video Online (Oct. 23, 2014) — Price check on honey? Bear cub startles Oregon drugstore shoppers. Rough Cut (no reporter narration). Video provided by Reuters
Powered by NewsLook.com
Dances With Wolves in China's Wild West

Dances With Wolves in China's Wild West

AFP (Oct. 23, 2014) — One man is on a mission to boost the population of wolves in China's violence-wracked far west. The animal - symbol of the Uighur minority there - is under threat with a massive human resettlement program in the region. Duration: 00:41 Video provided by AFP
Powered by NewsLook.com
Breakfast Debate: To Eat Or Not To Eat?

Breakfast Debate: To Eat Or Not To Eat?

Newsy (Oct. 23, 2014) — Conflicting studies published in the same week re-ignited the debate over whether we should be eating breakfast. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:

Strange & Offbeat Stories

 

Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins