Emerging problem pathogens: A review of resistance patterns over time

Despite the advances in chemotherapy for cancer patients, infectious complications remain an important cause of mortality and morbidity. Surveillance data report not only a shift in the aetiology of infections and resistance patterns in this patient population, but also important differences between regions and countries. Viridans streptococcal bacteraemias are common among cancer patients being second only to the coagulase-negative staphylococci. However, in certain centres in Europe Gram-negative bacilli have once again become the predominant infecting pathogens. The problems associated with emerging resistance have been widely documented in the literature. In some institutions methicillin-resistance among coagulase-negative staphylococci has reached 75%, and in others the incidence of extended-spectrum beta-lactamase producing Gram-negative bacilli has risen markedly. These shifts in antimicrobial susceptibility are important in guiding the choice of agents for febrile neutropenia. Antibiotic use and prophylaxis have both been associated with changes in susceptibility, and prescribing habits may influence emerging resistance. In this context, the choice of empirical antibiotic therapy and the use of prophylaxis should be driven by a sound understanding of local circumstances.