Isolation of multidrug-resistant Klebsiella oxytoca carrying blaIMP-8, associated with OXY hyperproduction, in the intensive care unit of a community hospital in Spain.

sion were polytraumatism, brain trauma, respiratory failure, acute renal failure, peritonitis, necrotic pancreatitis, spontaneous brain haemorrhage and subarachnoid haemorrhage. Twelve of 26 strains were from patients with ,2–12 weeks of exposure to linezolid. This study describes the molecular epidemiology and the mechanism of linezolid resistance in S. epidermidis strains from Greece. Two international clones (ST2 and ST22) were identified that carried known mutations of region V of 23S rRNA. Mutations G2576T and C2534T have been previously reported in strains arising from different institutions; mutation T2504A was detected for the first time in Greece and has also been recognized in the USA. The finding that strains from the USA with the T2504A mutation belong to different STs from ours indicates a continuous potential for the emergence of linezolid-resistant staphylococci. Dissemination of two common linezolid-resistant S. epidermidis clones among hospitals located in different areas of Greece (northern, central and south-western) is most likely due to linezolid exposure and patient-to-patient spread. This is more obvious in the ICUs of two university hospitals (hospitals B and D), where linezolid-resistant S. epidermidis strains were recovered within a 2–3 month period. Clones such as ST2 and ST22 that predominate in the hospital environment become linezolid resistant under selective pressure. After linezolid treatment, such resistant staphylococci colonize the skin, becoming the dominant cutaneous flora causing infections in critically ill patients. In order to preserve the usefulness of linezolid as a therapeutic agent, judicious use of antibiotics and application of strict infection control measures are essential.