title: An observational study on bloodstream extended-spectrum beta-lactamase infection in critical care unit: incidence, risk factors and its impact on outcome.
abstract: BACKGROUND
  The incidence of nosocomial infections caused by extended-spectrum beta-lactamase (ESBL) producing microbes is increasing rapidly in the last few years. However, the clinical significance of infections caused by ESBL-producing bacteria in ICU patients remains unclear. We did a prospective study to look for incidence, risk factors and outcome of these infections in ICU patients.
  
  
  METHODS
  Consecutive isolates of Escherichia coli and Klebsiella pneumoniae in blood cultures were included for the analysis. Patients were divided into two groups based on the production of ESBL. Primary outcome measure was ICU mortality. Logistic regression analysis was done to identify risk factors for ESBL production.
  
  
  RESULTS
  Among the 95 isolates tested, 73 (76.8%) produced ESBL. Transfer from other hospitals or wards (OR 3.65; 95% CI: 1.3-10.1 and RR 1.35; 95% CI: 1.05-1.73) and previous history of antibiotics usage (OR 3.54; 95% CI: 1.04-11.97 and RR 1.5; 95% CI: 0.89-2.5) were risk factors for ESBL production. There was no significant difference in ICU mortality (p=0.588), need for organ support between two groups.
  
  
  CONCLUSIONS
  There is a high incidence of ESBL producing organisms causing blood stream infections in critically ill patients. Transfer from other hospitals and previous antibiotic usage are important risk factors for ESBL production. However ESBL production may not be associated with a poorer outcome if appropriate early antibiotic therapy is instituted.
authors.affiliation: Department of Critical Care Medicine, Max Super Speciality Hospital, 1, Press Enclave Road, Saket, New Delhi, 110017, India. dr.prashantnasa@hotmail.com
authors.forename: Prashant
authors.initials: P
authors.lastname: Nasa
authors.forename: Deven
authors.initials: D
authors.lastname: Juneja
authors.forename: Omender
authors.initials: O
authors.lastname: Singh
authors.forename: Rohit
authors.initials: R
authors.lastname: Dang
authors.forename: Akhilesh
authors.initials: A
authors.lastname: Singh
mesh_terms: D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D016470:Bacteremia / Q000188:drug therapy / Q000453:epidemiology* / Q000382:microbiology; D003428:Cross Infection / Q000188:drug therapy / Q000453:epidemiology / Q000382:microbiology; D024901:Drug Resistance, Multiple, Bacterial; D004926:Escherichia coli / Q000201:enzymology* / Q000302:isolation & purification; D004927:Escherichia coli Infections / Q000188:drug therapy / Q000453:epidemiology* / Q000382:microbiology; D005260:Female; D006801:Humans; D015994:Incidence; D007194:India / Q000453:epidemiology; D007362:Intensive Care Units; D007709:Klebsiella / Q000201:enzymology* / Q000302:isolation & purification; D007710:Klebsiella Infections / Q000188:drug therapy / Q000453:epidemiology* / Q000382:microbiology; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D012720:Severity of Illness Index; D016896:Treatment Outcome; D001618:beta-Lactamases / Q000096:biosynthesis*
chemical_list: D000900:Anti-Bacterial Agents; D001618:beta-Lactamases