[1st Spanish epidemic of plasmid resistance to 3d generation cephalosporins: the implication of SHV-2].
BACKGROUND
The first spanish outbreak of bacterial strains showing resistance to third generation cephalosporins and due to the presence of the extended spectrum beta-lactamase SHV-2 is reported. This outbreak was observed in Madrid during the years 1988-1990 and involved the San Carlos University Hospital with the same type of isolates at the Ramón y Cajal University Hospital.


METHODS
The screening for extended-spectrum beta-lactamases was performed by the double-disk synergy test. Analytical isoelectric focusing and susceptibility tests were performed in all the strains showing a presumptive extended-spectrum beta-lactamase.


RESULTS
Fifty-nine strains belonging to four bacterial species (Klebsiella pneumoniae, 61%; Serratia marcescens, 31%; Klebsiella oxytoca, 5%, and Escherichia coli, 3%) showed a beta-lactamase of point isoelectric 7.6; the susceptibility tests demonstrated more resistance to cefotaxime and ceftriaxone than to ceftazidime and aztreonam.


CONCLUSIONS
The biochemical, kinetic and isoelectrofocusing parameters demonstrated the presence of a SHV-2 enzyme. The blind application of NCCLS breakpoints would lead to false "susceptibility" results in over 40% of the cases.
Fernández-Rodríguez
A
A
Servico de Microbiología, Hospital Clínico San Carlos, Madrid.
Reguera
J A
JA
Pérez-Díaz
J C
JC
Picazo
J J
JJ
Baquero
F
F
D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D002511:Cephalosporins / Q000145:classification / Q000494:pharmacology*; D003428:Cross Infection / Q000453:epidemiology / Q000382:microbiology; D004196:Disease Outbreaks; D004352:Drug Resistance, Microbial / Q000235:genetics; D004755:Enterobacteriaceae / Q000187:drug effects* / Q000201:enzymology / Q000302:isolation & purification; D004756:Enterobacteriaceae Infections / Q000453:epidemiology* / Q000382:microbiology*; D006801:Humans; D015994:Incidence; D008826:Microbial Sensitivity Tests; D011815:R Factors; D013030:Spain / Q000453:epidemiology; D013045:Species Specificity; D001618:beta-Lactamases / Q000235:genetics / Q000378:metabolism*
D001426:Bacterial Proteins; D002511:Cephalosporins; C062760:beta-lactamase SHV-2; D001618:beta-Lactamases
Primera epidemia española de resistencia plasmídica a cefalosporinas de tercera generación: implicación de SHV-2.