Risk factors of nosocomial infection with extended-spectrum beta-lactamase-producing bacteria in a neonatal intensive care unit in China.
BACKGROUND
To study risk factors of neonatal nosocomial infection caused by extended-spectrum beta-lactamase (ESBL)-producing bacteria in a neonatal intensive care unit (NICU).


METHODS
A retrospective cohort study was conducted in a university hospital NICU in south China. Medical records of neonatal nosocomial infection caused by Escherichia coli or Klebsiella pneumoniae were reviewed. Twenty-two neonates infected with ESBL-producing bacteria (case patients) were compared with 17 patients infected with non-ESBL producing strains (controls). Univariable and multivariable logistic regression were performed to analyze risk factors for infection with ESBL-producing strains. The spectrum of antimicrobial resistance of ESBL-positive E. coli or K. pneumoniae was also examined.


RESULTS
Both univariable and multivariable logistic regression analysis revealed that preterm low birth weight, prolonged mechanical ventilation (> or = 7 days) and prior use of third-generation cephalosporins were risks factors for ESBL-producing E. coli or K. pneumoniae infection (p < 0.05), with an odd ratio of 6.43 (95% CI: 1.51-27.44; p = 0.017), 7.50 (95% CI: 1.38-40.88; p = 0.017) and 9.00 (95% CI: 1.65-49.14; p = 0.008) respectively. However, the length of hospital stay before isolation of pathogens, endotracheal intubation, presence of a central venous catheter, days on third-generation cephalosporins and prior use of beta-lactamase inhibitors were not statistically significant (p > 0.05). Resistance of ESBL-positive strains to piperacillin, tobramycin, aztreonam and cephalosporins was significantly higher than that of ESBL-negative ones (p < 0.05). ESBL-producing strains appeared susceptible to carbapenem, fluoroquinolones, and beta-lactamase inhibitor combination piperacillin-tazobactam.


CONCLUSIONS
Preterm low birth weight, prolonged mechanical ventilation and prior use of third-generation cephalosporins are risks factors for nosocomial infection with ESBL-producing bacteria in NICU.
Huang
Y
Y
Dept. of Pediatrics, First Affiliated Hospital, Sun Yat-sen University, Guangzhou, 510080, People's Republic of China.
Zhuang
S
S
Du
M
M
D000900:Anti-Bacterial Agents / Q000494:pharmacology / Q000627:therapeutic use; D001419:Bacteria / Q000201:enzymology* / Q000302:isolation & purification; D016022:Case-Control Studies; D002511:Cephalosporins / Q000627:therapeutic use; D002681:China / Q000453:epidemiology; D015331:Cohort Studies; D003428:Cross Infection / Q000453:epidemiology* / Q000382:microbiology*; D004926:Escherichia coli; D004927:Escherichia coli Infections / Q000453:epidemiology* / Q000382:microbiology*; D005260:Female; D006801:Humans; D007223:Infant; D007230:Infant, Low Birth Weight; D007231:Infant, Newborn; D007363:Intensive Care Units, Neonatal; D007710:Klebsiella Infections / Q000453:epidemiology* / Q000382:microbiology*; D007711:Klebsiella pneumoniae; D016015:Logistic Models; D008297:Male; D008826:Microbial Sensitivity Tests; D015999:Multivariate Analysis; D012121:Respiration, Artificial; D012189:Retrospective Studies; D012307:Risk Factors; D018440:beta-Lactam Resistance; D001618:beta-Lactamases / Q000096:biosynthesis*
D000900:Anti-Bacterial Agents; D002511:Cephalosporins; D001618:beta-Lactamases