What is the impact of a rapid-diagnostic test (Etest) in the treatment of patients with Gram-negative bacteraemia?

Abstract number: P1606

Moral-Escudero E., García-Vázquez E., Fernández-Rufete A., Hernández-Torres A., Ruiz J., Yagüe G., Albendín-Iglesias H., Herrero J.A., Gómez J.

Objectives: To evaluate influence of a rapid-diagnostic test (RT) in antibiotic (AB) therapeutic decisions in non-paediatric patients with Gram negative bacteraemia (GNB. Patients and Methods: A RT (validated in 5 hours)consisting in direct antibiogram (Mueller-Hinton agar) was done in blood isolates of GNB. AB used in the E-test were ciprofloxacin, cefotaxime, cefepim, cefepim-clavulanic, and imipenem. GNB were also identified and sensitivity test performed by standard criteria (McFarland). RT information was provided at the physician in a 24 hour-working routine (<24 hours after blood cultures were obtained). Data collection has been done according to a standard protocol (epidemiological, clinical, microbiological and laboratory data). Information about empirical treatment was registered (T1) as well as the AB administered once the information of RT was provided (T2) and on the ideal AB the Infectious Diseases consultant would have prescribed (considering not only sensitivity results but also clinical characteristics, localization of infection and minimum "ecological" impact) (T3). Decision about T2 was always taken by the physician in charge or the physician on duty. The economic cost of 72 hours (mean "won time" by RT compared to standard sensitivity test) of T1, T2 and T3 was calculated according to the price of AB provided by our Pharmacy Department; RT cost was 14[euro].

Results: RT was performed in 99 patients; one blood culture yield 2 different GNB; 4 patients died before RT results were available (excluded for the analysis); 5 patients died due to non-infectious complications and 9 died with septic shock (mortality 18.2%). Microbiological isolates were: E. coli (60%; 19.3% ESBL), K. pneumoniae (10.5%; 2% ESBL), P. aeruginosa (10.5%) and other enterobacteria 13.7%. Main AB used in T1 were quinolones (14%), 3rd generation cephalosporins (16%), carbapenems (15%) and piperacillin–tazobactam (28.3%). T1 was considered adequate in 26.3% and T2 in 60%. Economical cost of 72 hours of T1, T2 and T3 per patient was 70.6[euro], 69.9[euro] and 44.2[euro]; the economical cost of T3 including 14[euro] of the RT is 58.2[euro].

Conclusions: In an era of increasing MDR-GNB, RT provides early and useful information about AB treatment options; this data should be interpreted by an Infectious Diseases specialised physician to make information economically and "ecologically" profitable. New diagnostic techniques are not cost-effective if they are not properly interpreted.

Session Details

Date: 10/04/2010
Time: 00:00-00:00
Session name: Abstracts 20th European Congress of Clinical Microbiology and Infectious Diseases
Location: Vienna, Austria, 10 - 13 April 2010
Presentation type:
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