Neonatal intensive care unit outbreak caused by a strain of Klebsiella oxytoca resistant to aztreonam due to overproduction of chromosomal β-lactamase

Klebsiella oxytoca strains resistant to both aztreonam and ceftriaxone were isolated from six neonates in a neonatal intensive care unit and water reservoirs of two humidifiers attached to the neonatal incubators. These isolates were assumed to be of the same clone because they were characterized by...

Full description

Saved in:
Bibliographic Details
Published in:The Journal of hospital infection 2001-08, Vol.48 (4), p.281-288
Main Authors: Jeong, S.H., Kim, W.M., Chang, C.L., Kim, J.M., Lee, K., Chong, Y., Hwang, H.Y., Baek, Y.W., Chung, H.K., Woo, I.G., Ku, J.Y.
Format: Article
Language:English
Subjects:
aztreonam
Aztreonam - pharmacology
Bacterial diseases
Bacterial Proteins
beta-Lactam Resistance - genetics
beta-Lactamases - genetics
beta-Lactamases - metabolism
Biological and medical sciences
Ceftriaxone - pharmacology
Cross Infection - epidemiology
Electrophoresis, Gel, Pulsed-Field
Human bacterial diseases
Humans
Infant, Newborn
Infectious diseases
Intensive Care Units, Neonatal
Klebsiella - drug effects
Klebsiella - enzymology
Klebsiella - genetics
Klebsiella Infections - epidemiology
Klebsiella oxytoca
Medical sciences
Microbial Sensitivity Tests
Miscellaneous
Point Mutation
Polymerase Chain Reaction
Tropical medicine
β-lactamase (overproduction)
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Klebsiella oxytoca strains resistant to both aztreonam and ceftriaxone were isolated from six neonates in a neonatal intensive care unit and water reservoirs of two humidifiers attached to the neonatal incubators. These isolates were assumed to be of the same clone because they were characterized by the same antimicrobial susceptibility and pulsed field gel electrophoresis patterns. It was established that the drug resistance was attributed to overproduction of chromosomally encoded Kl β-lactamase. It was determined that an isolate (K. oxytoca H1) contained a high enzyme concentration (27mg/100mg of protein in enzyme extracts), at least 27 times higher than the control K. oxytoca N1. It was also demonstrated that isolates had a point mutation in the — 35 concensus region of the promotor gene ofblaOXY-2 leading to enzyme overproduction. Outbreaks caused by K1 hyperproducers have not previously been described.
ISSN:0195-6701
1532-2939
DOI:10.1053/jhin.2001.1018