Which of the following statement is false about extended spectrum beta-lactamases (ESBL)?
Extended-spectrum beta-lactamases (ESBL) are enzymes that confer resistance to most beta-lactam antibiotics, including penicillins, cephalosporins, and the monobactam aztreonam. lmipenem(carbapenem): It is an extremely potent and broad-spectrum Beta-lactam antibiotic whose range of activity includes grampositive cocci, Enterobacteriaceae, Ps. aeruginosa, Listeria as well as anaerobes like Bact. fragilis and Cl. difficile. It is resistant to most Beta-lactamases; inhibits penicillinase producing staphylococci and some MRSA. Extended-spectrum beta-lactamase (ESBL) Members of the family commonly express plasmid encoded b-lactamases (e.g., TEM-1, TEM-2, and SHV-1). which confer resistance to penicillins but not to expanded-spectrum cephalosporins. In the mid-1980s, a new group of enzymes, the extended-spectrum b-lactamases (ESBLs), was detected (first detected in 1979).The prevalence of ESBL-producing bacteria have been gradually increasing in acute care hospitals.ESBLs are beta-lactamases that hydrolyze extended-spectrum cephalosporins with an oxyimino side chain. These cephalosporins include cefotaxime, ceftriaxone, and ceftazidime, as well as the oxyimino-monobactam aztreonam. Thus ESBLs confer multi resistance to these antibiotics and related oxyimino-beta lactams. In typical circumstances, they derive from genes for TEM-1, TEM-2, or SHV-1 by mutations that alter the amino acid configuration around the active site of these b-lactamases. A broader set of b-lactam antibiotics are susceptible to hydrolysis by these enzymes. An increasing number of ESBLs not of TEM or SHV lineage have recently been described.The ESBLs are frequently plasmid encoded. Plasmids responsible for ESBL production frequently carry genes encoding resistance to other drug classes (for example, aminoglycosides). Therefore, antibiotic options in the treatment of ESBL-producing organisms are extremely limited. Carbapenems are the treatment of choice for serious infections due to ESBL-producing organisms, yet carbapenem-resistant (primarily eapenem resistant) isolates have recently been repoed. ESBL-producing organisms may appear susceptible to some extended-spectrum cephalosporins. However, treatment with such antibiotics has been associated with high failure rates. ESSENTIALS OF MEDICAL PHARMACOLOGY, en.wikipedia.org, www.uptodate.com K.D.TRIPATHI SIXTH EDITION PAGE NO:708
These can hydrolyze penicillins, cephalosporins as well as monobactams
Carbapenems are sensitive to ESBL
Amber classification of ESBL is based on structural differences
Third and fouh generation cephalosporins are used for detection of ESBL,
Chemotherapy