Isolation of Microbial Strains Producing ß-Lactamases with Extended Spectrum from Hospital Environment
Roxana Moldovan, Monica Licker, Mihaela Crãciunescu, and Crenguta Boer
Department of Microbiology, University of Medicine and Pharmacy, Timisoara, Romania
Corresponding author: Roxana Moldovan
Calea Bogdãnetilor, no.54,
RO-1900, Timisoara
Romania
Telephone: (+40) 56 142 454
Fax number: (+40) 56 192 101
E-mail: microbiolog@gmx.net
CEJOEM 2000, Vol.6. No.2-3.:176-182
Key words:
Newborns, gram-negative rods, BLSE
Abbreviations:
BLSE = ß-lactamase with extended spectrum
CTX = cefotaxime
CAZ = ceftazidime
ATM = aztreonam
KgnToNtA = phenotype resistance to aminoglycosides (kanamycin, gentamicin, tobramycin, netilmicin, amikacin)
Abstract:
256 strains of gram-negative bacilli were isolated from various pathological samples collected
from mothers and newborns hospitalized in a department of obstetrics and gynecology. The antibiotic
susceptibility of the strains was determined by the disk diffusion method. The aim of the study
was to identify the strains that were resistant to ß-lactamine due to production of
ß-lactamase with extended spectrum (BLSE), as well as to other mechanisms (penicilinase,
cephalosporinase producers). Three BLSE strains (E. coli, Enterobacter cloacae and Klebsiella
oxytoca) were found, all of them isolated from premature newborns. As this type of enzyme
detection is of high microbiological importance, new sensitive and specific methods accessible to
any laboratory are permanently searched for. In the simple susceptibility tests made by the disk
diffusion method, BLSE strains show a characteristic “champagne stopper” pattern (inhibition area
between the amoxicillin + clavulanic acid, cefotaxime, ceftazidime and aztreonam drugs).
Received: 31 July 2000
Accepted: 30 October 2000
| Back |