A 5year retrospective review of BSI in a national bone marrow transplantation unit

Abstract number: P1470

Objectives: Blood-stream infection (bsi) is an important cause of morbidity and mortality among patients with haematological malignancy and those undergoing bone marrow transplantation. The spectrum of infections and susceptibility patterns are extremely important in determining the empiric antimicrobial choice for febrile neutropenia. We performed at 5-year retrospective review of bsi among haematology patients in order to review causative organisms and their susceptibility patterns and compare to National and European data.

Methods: St. James Hospital is a 1,000 bed tertiary referral university hospital with a 21 bed HEPA-filtered, positive pressure, purpose built Haematology ward that includes the National Bone Marrow transplantation unit.

A retrospective five-year review of all episodes of bsi between 2005 and 2009 was undertaken. An episode of bsi was defined as isolation of a micro-organism from blood cultures. All isolates recovered from a patient within 14 days of a positive blood culture were counted as a single episode. Two isolates of coagulase negative staphylococci or corynebacteria from one blood culture set were required to be considered significant.

Results: There were 623 episodes of bsi; 50% were caused by Gram-negative organisms (GNO) and 47% by Gram-positive organisms (GPO) (Table 1).

Coagulase negative staphylococci were the predominant cause of bsi (27%), followed by E. coli (19%) and Klebsiella species (10%). 14 of 39 (36%) of Staphylococcus aureus bsi were caused by Meticillin Resistant Staphylococcus aureus. 29 of 45 (64%) of Enterococcus faecium bsi were vancomycin resistant.

Ciprofloxacin resistance among GNO rose from 8% in 2005 to 33% in 2007 and decreased to 8% in 2009 with a similar trend in gentamicin resistance. Ciprofloxacin resistance rates reflected ciprofloxacin usage. Less than 1% of GNO displayed extended spectrum b-lactamase production.

Conclusion: Our study demonstrates that GNO account for slightly more bsi's than GPO which is consistent with more recent studies. Resistance to methicillin among MRSA are similar to national data, but vancomycin resistance among enterococci is higher. It is likely that quinolone resistance among GNOs reflects quinolone usage and has a similar effect on gentamicin resistance.

Table 1: Distribution of organisms 2005–2009

n (%)20052006200720082009Total
GP bacteria47 (48.4)37 (38.5%)73 (50%)69 (51%)80 (45%)306(47)
GN bacteria48 (49.4)56 (58.3%)70 (49%)60 (44%)94 (54%)328(50.4)
n = number; GP: Gram positive, GN: Gram negative.

Session Details

Date: 07/05/2011
Time: 00:00-00:00
Session name: Abstracts of 21st ECCMID / 27th ICC
Location: Milan, Italy, 7 - 10 May 2011
Presentation type:
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