[Microbiological characteristics of pathogens causing bacteremia among hospitalized pediatric oncology patients with fever and neutropenia]

Abstract

Background: Bacterial infections are a major threat to pediatric oncology patients with fever and neutropenia. Current management consists of empiric broad-spectrum antibiotics and prompt medical evaluation. Local bacterial susceptibility rates were published in 2005, and the local protocol (piperacillin and amikacin) was established as an adequate empiric treatment with -100% efficiency against the common pathogens in our pediatric hemato-oncology ward.

Aim: To characterize the spectrum of bacteria isolated from blood cultures at the pediatric hemato-oncology ward between 2008- 2010, and to evaluate the current protocol.

Methods: A prospective study, conducted in the pediatric hemato-oncologic ward among hospitalized children (2 months - 18 years) with fever and neutropenia. Blood cultures from peripheral blood and central lines were obtained from all patients at admission. Bacterial resistance to various antimicrobial agents was determined.

Results: During 2008-2010, 195 admissions (105 children) due to fever and neutropenia were recorded. Approximately 30% of all blood cultures were positive for a pathogen with -50% Gram positive bacteria mostly CONS. The most prevalent Gram negative bacteria were acinetobacter and klebsiella spp. Candida species were isolated from 7% of positive cultures. Susceptibility rates for the current empiric antimicrobial regimen were about 90%. CONS bacteremia rate increased from 4% in 2000-2002 to 29% in 2008-2010 (p < 0.01).

Conclusions: The currently applied empiric antimicrobial protocol is an optimal first line regimen, considering the susceptibility of the most common pathogens. Judicious use of carbapenems for gram negative bacteria and glycopeptides or other novel antimicrobial agents in cases of CONS bacteremia is required.