Antibiotic therapy in granulocytopenic
cancer patients, the risk factors predisposing these patients to
infection, and the signs, symptoms and types of
infections occurring in these patients are reviewed. The four most commonly isolated organism at most
cancer treatment centers are Escherichia coli, Klebsiella spp., Pseudomonas aeruginosa and Staphylococcus aureus. Early antimicrobial
therapy with broad-spectrum
antibiotics before culture results are known produces cure rates of approximately 70%, regardless of the combination used. The most important predictor of response to any antibacterial regimen is a rise in the absolute granulocyte count. The current recommended
fever regimen would be
carbenicillin (or
ticarcillin) with an
aminoglycoside. The choice of an
aminoglycoside depends on the prevailing organism sensitivities at a particular institution; in many cases,
gentamicin sulfate is suitable. Addition of a
cephalosporin to the two-
drug regimen offers little increase in cure rates, except whem
aminoglycoside-resistant Enterobacteriaceae are prevalent. Because of nephrotoxicity produced with combinations of
cephalothin sodium and the
aminoglycosides,
cefazolin sodium would be the current
cephalosporin of choice. An alternate third
drug to be considered is
co-trimoxazole, a broad-spectrum antimicrobial not yet commercially available in parenteral form. In the absence of a clinical response to appropriate antimicrobial
therapy in documented
infections, granulocyte transfusions may be indicated.