Autologous Bone Marrow Transplantation - Blog Science Connections

Newer Antibiotic Regimens in Cancer Patients
Kenneth V. I. Rolston
The use of empiric antimicrobial therapy for the management of febrile
episodes in neutropenic cancer patients is now accepted as standard
practice. Bacterial infections in this group of patients are caused by a variety
of gram-positive and gram-negative organisms that form the endogenous
flora of the skin, gastrointestinal tract, and oropharynx (1). In order to provide
broad-spectrum coverage before the identification of the causative pathogen(s),
empiric regimens have traditionally consisted of combinations of two
(or more) antimicrobial agents (2). The agents commonly used are the
aminoglycosides (gentamicin, tobramycin, amikacin), the antipseudomonal
penicillins (ticarcillin, mezlocillin, piperacillin), and the extended-spectrum or
third-generation cephalosporins (moxalactam, cefoperazone, ceftazidime).
Several prospective trials using a variety of such combinations have demonstrated
overall clinical responses in 70-80% of patients (3-6).
A number of recent developments have prompted clinical investigators
to reevaluate the empiric regimens frequently employed in neutropenic
patients. These developments include: a) the availability of several newer
agents such as the monobactams, the carbapenems, and the quinolones,
which might be equivalent or superior to older agents or combinations; b)
increasing resistance of common gram-negative and gram-positive pathogens
to older agents; c) a change in the pattern of organisms causing
infections in cancer patients; and d) the escalating cost of medical care and
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