title: Alterations in the microbial flora and in the incidence of bacteremia at a university hospital after adoption of amikacin as the sole formulary aminoglycoside.
abstract: Because of the rapid emergence of resistance to gentamicin and tobramycin among isolates of aerobic and facultative gram-negative bacteria at our university hospital, we designed a prospective study to track aminoglycoside resistance, bacteremic episodes, and bacteremia-associated deaths before and after the institution of amikacin as the sole formulary aminoglycoside. From June 1984 through June 1987 (immediately before this policy change), amikacin accounted for only 20% of patient-days of aminoglycoside therapy, and rates of resistance to gentamicin, tobramycin, and amikacin among aerobic and facultative gram-negative bacterial isolates were 12.8%, 10.8%, and 5.9%, respectively. During the next 30 months (immediately after the change in policy), amikacin accounted for 98% of patient-days of aminoglycoside therapy, and rates of resistance to gentamicin, tobramycin, and amikacin were 6.3%, 5.0%, and 3.3%, respectively. Furthermore, during the latter 30 months, the incidence of both bacteremia and bacteremia-associated death decreased significantly. Hospitals at which resistance to gentamicin or tobramycin is increasing among the gram-negative flora may benefit from the use of amikacin as the principal aminoglycoside.
authors.affiliation: Section of Infectious Diseases, Louisiana State University Medical Center, Shreveport 71130.
authors.forename: J W
authors.initials: JW
authors.lastname: King
authors.forename: M C
authors.initials: MC
authors.lastname: White
authors.forename: J R
authors.initials: JR
authors.lastname: Todd
authors.forename: S A
authors.initials: SA
authors.lastname: Conrad
mesh_terms: D000583:Amikacin / Q000494:pharmacology / Q000627:therapeutic use*; D016470:Bacteremia / Q000188:drug therapy* / Q000453:epidemiology / Q000382:microbiology; D004352:Drug Resistance, Microbial; D005839:Gentamicins / Q000494:pharmacology / Q000627:therapeutic use; D006090:Gram-Negative Bacteria / Q000187:drug effects* / Q000302:isolation & purification; D016905:Gram-Negative Bacterial Infections / Q000188:drug therapy* / Q000453:epidemiology / Q000382:microbiology; D006094:Gram-Positive Bacteria / Q000302:isolation & purification; D016908:Gram-Positive Bacterial Infections / Q000188:drug therapy / Q000453:epidemiology / Q000382:microbiology; D006801:Humans; D015994:Incidence; D008145:Louisiana / Q000453:epidemiology; D011446:Prospective Studies; D014031:Tobramycin / Q000494:pharmacology / Q000627:therapeutic use
chemical_list: D005839:Gentamicins; D000583:Amikacin; D014031:Tobramycin