Bacterial pathogens isolated from patients with bloodstream infection

Abstract number: R2391

Nica M., Biolan T., Mozes E., Dascalu A., Caliga D., Melinte V., Ceausu E., Calistru P., Tudor A., Apostol I.

Objectives: To determine the frequency of pathogens isolated from 1483 patients with Blood Stream Infections (BSI) and to investigate their resistance patterns, between January 2005 and July 2007, in "Dr. V. Babes" Hospital of Infectious and Tropical Diseases, Bucharest.

Methods: Blood cultures were performed using the BacT/ ALERT 120 automated system. ATB/ Expression and VITEK 2 Compact automated system (bioMerieux, France) was used for identification and resistance testing of pathogens, according to NCCLS 2005–CLSI 2007. Internal quality control was provided by using S. aureus ATCC 25923, S. pneumoniae ATCC 49619, E. coli ATCC 25922, P. aeruginosa ATCC 27853.

Results: A total of 3561 blood cultures were screened for aerobic and anaerobic bacteria. Bacteraemia occurred in 176 cases (4.9%). Out of 176 isolated strains, 107 were Gram-positive (60.8%) and 69 were Gram-negative (39.2%). Among Gram-positive, the most prevalent was Coagulase-Negative Staphylococci 34.6%, followed by Staphylococcus aureus 26.2%, Streptococcus pneumoniae 14.0%, Enterococcus spp. 4.7%. The most frequent of streptococci were Streptococcus pyogenes and Streptococcus bovis (3.7% each). Among the Gram-negative Escherichia coli was 47.8%, Klebsiella pneumoniae 15.9%, Salmonella spp. 13.0%. In lower rates we found: other Enterobacteriaceae, Acinetobacter baumannii, Pseudomonas aeruginosa, Neisseria meningitidis, Haemophilus influenzae and anaerobic bacteria. All Gram-positive isolates were susceptible to glycopeptides. 20/ 37 of CoNS were MRSCN, 13/ 37 resistant to fluoroquinolone, 12/ 37 to gentamicin. 9/28 of Staphylococcus aureus were MRSA, 4/28 were resistant to aminoglycosides, 5/28 to fluoroquinolones. In S. pneumoniae isolates, 1/15 was reported with high level resistance to penicillin. E. coli and K. pneumoniae strains produced ESBL in 12.1% and 45.4% respectively. Most of A. baumannii and P. aeruginosa strains were susceptible to carbapenems.

Conclusions: 1. CoNS (21.0%) were the leading cause of BSI, followed by E. coli (18.7%), S. aureus (15.9%), S. pneumoniae (8.5%). 2. All Gram-positive isolates were susceptible to glycopeptides. 3. 45.4%K. pneumoniae was ESBL positive. 4. Carbapenems had a good activity against Gram-negative bacilli.

Session Details

Date: 19/04/2008
Time: 00:00-00:00
Session name: 18th European Congress of Clinical Microbiology and Infectious Diseases
Location: Barcelona, Spain
Presentation type:
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