Blood stream infections in cancer patients: A single center experience of isolates and sensitivity pattern

Background : Up to 10% of patients who develop a nosocomial blood stream infection (BSI) in the hospital have an underlying malignancy. The treatment of infections in patients with malignancy often relies on the use of established guidelines along with the consideration of the local microbiology and antibiotic sensitivity patterns of possible etiologic agents.
AIMS: This study attempts to identify the likely etiologic agents and the antibiotic sensitivity profile of BSIs in cancer patients.
Settings and Design: This was a retrospective study.
Methods and Material: The study was conducted at a tertiary care center for cancer patients, in which samples representing blood stream infections sent from the Medical Oncology services of the hospital during the year of 2007 were analysed. The microbiological profile and antibiotic sensitivity pattern of these isolates was studied.
Results: There were 484 isolates that represented BSIs. The most common bacterial isolates from patients with cancer were Pseudomonas spp. (30.37%), Staphylococcus aureus (12.6%) and Acinetobacter spp. (11.57%). Meropenem was the most effective antibiotic with 71.2% sensitivity to the bacterial isolates it was tested against. Oxacillin resistance was seen in 18% of S. aureus isolates.
Conclusion: Gram-negative bacteria were more common as etiologic agents of BSIs in cancer patients. The poor activity of the primary empirical agents for infections in cancer namely ceftazidime and piperacillin-tazobactam is alarming.Strict regulation of vancomycin use should be considered in areas where there is a low prevalence of methicillin-resistant S. aureus (MRSA).