Association of antibiotic utilization measures and control of multiple-drug resistance in Klebsiella pneumoniae.
OBJECTIVE
To study the association of antibiotic-utilization measures and control of multidrug-resistant (MDR) Klebsiella pneumoniae after emergence in two hospitals in our medical center.


METHODS
Rates of MDR K. pneumoniae at two hospitals were compared before and after acute interventions, including emphasis on Contact Precautions and education in antibiotic utilization. Antipseudomonal beta-lactam antibiotic use was measured before and after the interventions at both hospitals. Pulsed-field gel electrophoresis of whole cell DNA was used as a marker of strain identity.


RESULTS
Clonal strain dissemination was the major mechanism of emergence at hospital A; emergence was polyclonal at hospital B. Antibiotic-utilization interventions at both institutions included physician education regarding the association of ceftazidime use and MDR K. pneumoniae. At hospital A, ceftazidime use decreased from 4,301 g in the preintervention period, to 1,248 g in the postintervention period. Piperacillin-tazobactam use increased from 12,455 g to 17,464 g. Ceftazidime resistance in K. pneumoniae decreased from 110 (22%) of 503 isolates to 61 (15%) of 407 isolates (P<.05); piperacillin-tazobactam resistance decreased from 181 (36%) of 503 to 77 (19%) of 407 isolates (P<.05). At hospital B, ceftazidime use decreased from 6,533 g in the preintervention period to 4,792 g in the postintervention period. Piperacillin-tazobactam use increased from 58,691 g to 67,027 g. Ceftazidime resistance in K. pneumoniae decreased from 42 (10%) of 415 isolates to 19 (5%) of 383 isolates (P<.05). Piperacillin-tazobactam resistance decreased from 91 (22%) of 415 isolates to 54 (14%) of 383 isolates (P<.05). Follow-up data showed continued decrease in piperacillin-tazobactam resistance despite increased use at both hospitals.


CONCLUSIONS
Antibiotic-use measures may be particularly important for control of MDR K. pneumoniae, whether emergence is clonal or polyclonal.
Department of Medicine, University of Texas Health Science Center at San Antonio, USA.
J E
JE
Patterson
T C
TC
Hardin
C A
CA
Kelly
R C
RC
Garcia
J H
JH
Jorgensen
D000900:Anti-Bacterial Agents / Q000494:pharmacology* / Q000627:therapeutic use; D003428:Cross Infection; D004269:DNA, Bacterial / Q000032:analysis; D018432:Drug Resistance, Multiple; D016521:Electrophoresis, Gel, Pulsed-Field; D006801:Humans; D017053:Infection Control / Q000379:methods; D007710:Klebsiella Infections / Q000188:drug therapy* / Q000635:transmission; D007711:Klebsiella pneumoniae / Q000187:drug effects* / Q000235:genetics / Q000472:pathogenicity; D007769:Lactams
D000900:Anti-Bacterial Agents; D004269:DNA, Bacterial; D007769:Lactams