Bacteraemia in neutropenic patients

Empirical antibiotic therapy in febrile neutropenic patients should reflect local patterns of microbial isolates and antibiotic resistance. The aim of this study was to review blood culture isolates and antibiotic resistance from neutropenic cancer patients over a four year period as a guide to empiric antimicrobial therapy. All positive blood culture isolates from a mixed haematology/oncology unit between 1988 and 1991 were evaluated retrospectively. Episodes of bacteraemia rose from 9% in 1988 to 13.7% in 1991. Gram-positive organisms accounted for between 61.3% and 72.7% in each of the four years. Isolates of Gram-negative organisms were between 23.6% and 31.5% of which a significant proportion are due to a heterogeneous group of hydrophilic, non-fermentative organisms. Fungal blood culture isolates accounted for between 3% and 4% each year. All Gram positive isolates were sensitive to vancomycin. Piperacillin was the least active B-lactam antibiotic and tobramycin the least active aminoglycoside reflecting the widespread usage of these agents in the unit. In conclusion, bacteraemic episodes are increasing in this patient population and are mainly due to Gram-positive organisms probably as a result of the extensive use of surgically implanted venous access devices.