[Incidence of blood stream infections of 1265 patients with hematopoietic stem cell transplantation and analysis of pathogenic bacteria].

Objective

To analyze the incidence and microbiological features of blood stream infections (BSI) of patients with hematopoietic stem cell transplantation (HSCT) and to provide laboratory data for empirical use of antibiotic for the HSCT patients with BSI.

Methods

The incidence of bloodstream infection, the positive rate of blood culture, bacterial spectrum and drug resistance were analyzed in 1 265 HSCT recipients during 2013 and 2015 were retrospectively studied.

Results

Of 1265 patients undergoing HSCT, 1 422 cases of suspected BSI occurred in 784 patients (61.98%) , and 464 patients (59.2%) were in the stage of agranulocytosis (ANC<0.5×10(9)/L) . The detection rate of pathogens in 2013-2015 was about 20% and increase year after year. Of the 401 strains detected, 221 were Gram-negative (G(-)) bacteria (55.1%) , 165 Gram-positive (G(+)) bacteria (41.2%) and 15 fungi (3.7%) . Escherichia coli (16.0%) , Staphylococcus epidermidis (15.5%) and Klebsiella pneumoniae (11.2%) were listed the top three. The proportion of multidrug resistant Acinetobacter Bauman and Stenotrophomonas maltophilia was 64.70% and 63.64% respectively, and methicillin resistant Staphylococcus aureus (MRSA) was more than half (57.14%) . The ratio of vancomycin resistant Enterococci (VRE) and carbapenem resistant Enterobacteriaceae (CRE) was 14.29% and 6.78% respectively. More than 40% Enterobacteriaceae bacteria were resistant to three or four generation cephalosporin antibiotics, and less were resistant to the carbapenems (6.4%) . However, many non-fermentating bacteria were highly resistant to these antibiotics and showed diversity among different strains, with a rate of 47.8% resistance to carbapenems. All the Staphylococcus were sensitive to vancomycin, teicoplanin and linezolid.

Conclusions

The incidence of BSI in patients with HSCT was high, and the pathogens were mainly G(-) bacteria. In addition to Enterobacteriaceae, the proportion of non-fermentative bacteria was quite high. No Staphylococcus detected were resistant to vancomycin, teicoplanin and linezolid.