Rectal colonization and frequency of enterococcal cross-transmission among prolonged-stay patients in two Swedish intensive care units.
The aims of this study were to gain insight into the dynamics of the rectal flora during prolonged ICU stay, with a particular focus on colonization and cross-transmission with resistant pathogens, and to evaluate methods for the rapid isolation of relevant bacteria from rectal swabs. Patients admitted to a general intensive care unit (GICU) or a cardiothoracic ICU (TICU) at the University Hospital of Linköping, Sweden, between 1 November 2001 and January 2002 with a length of stay > 5 d were included (n = 20). Chromogenic UTI agar medium was used for discrimination of different species, and appropriate antibiotics were added to detect resistance. Direct plating was compared to enrichment broth for a subset of specimens. The study showed an early alteration in rectal flora, with a dramatic decrease in Gram-negative rods in favour of Gram-positive bacteria. An ampicillin- and high-level gentamicin resistant clone of Enterococcus faecium was found in 6 of 10 patients in the GICU and 2 of 11 patients in the TICU. Enrichment broth did not enhance the detection of Gram-negative bacteria compared to direct plating on Chromogenic UTI medium, but enrichment broths were needed for optimal detection of resistant Gram-positive bacteria.
Hällgren
Anita
A
Department of Clinical and Molecular Medicine, Faculty of Health Sciences, Linköping, Sweden. aniha@imk.liu.se
Burman
Lars G
LG
Isaksson
Barbro
B
Olsson-Liljeqvist
Barbro
B
Nilsson
Lennart E
LE
Saeedi
Baharak
B
Walther
Sten
S
Hanberger
Håkan
H
D000368:Aged; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D001424:Bacterial Infections / Q000188:drug therapy* / Q000635:transmission; D003428:Cross Infection / Q000188:drug therapy / Q000382:microbiology*; D016984:Enterococcus faecium / Q000302:isolation & purification*; D005260:Female; D006090:Gram-Negative Bacteria / Q000145:classification / Q000187:drug effects / Q000302:isolation & purification*; D006094:Gram-Positive Bacteria / Q000145:classification / Q000187:drug effects / Q000302:isolation & purification*; D006801:Humans; D007362:Intensive Care Units; D007902:Length of Stay; D008826:Microbial Sensitivity Tests; D012007:Rectum / Q000382:microbiology*; D013548:Sweden
D000900:Anti-Bacterial Agents