RESUMEN
Empirical antimicrobial therapy is usually started in febrile neutropenic patients without having culture results. The aim of this study was to help determine the policies of empirical antibiotic usage in febrile neutropenic children by detecting the antimicrobial susceptibility profile in this group of patients. In this study 811 blood cultures taken from neutropenic children hospitalized at the Department of Oncology of Gaziantep Children Hospital November 2007 and February 2010 were retrospectively evaluated. Blood cultures were routinely collected in aerobic and anaerobic media and incubated using the BACTEC system. Identification and antimicrobial susceptibility testing of the isolates to antimicrobial agents was performed using the Vitek2(®) system according to the recommendations of the Clinical and Laboratory Standards Institute. Of 811 isolates analyzed, 128 (56.4%) were gram positive cocci, 43 (18.9%) were gram negative bacilli and fungi accounted for 56 (24.7%). The main isolated Gram-positive bacteria from blood were coagulase-negative staphylococcus (56.7%), followed by methicillin-resistant Staphylococcus aureus (14.1%). S. aureus and Streptococcus spp. were all susceptible to linezolid, vancomycin and teicoplanin. S aureus was still susceptible to few other antimicrobial agents such as tetracycline (82.4%), chloramphenicol (55.6%). Seven E. faecium, 7 E. fecalis and 1 E. hirae was isolated from blood cultures. Vancomycin resistance was detected in 6 out of 15 (40%) Enterococcus spp. isolates. Among gram-negative bacteria E. coli (30.2%) was followed by Klebsiella pneumoniae (20.9%) and Proteus spp. (18.6%). Imipenem (89.2%), meropenem (86.6%), chloramphenicol (88.9%), amicasin (82.4%) and fosfomycin (81.3%) showed highest susceptibility in vitro activity against all Gram-negative isolates. To know the antimicrobial susceptibility profile of the pathogens frequently isolated from febrile neutropenic children and to consider this profile before starting an empirical antibiotic therapy would help the clinics which have any role in the treatment of these patients to determine the empirical antibiotic usage policies.
RESUMEN
Enterococci are members of normal flora of human gastrointestinal system, and occupy the first places among the agents causing nosocomial infection. The most frequent origin of vancomycin-resistant enterococcus (VRE) is the gastrointestinal colonization in hospitalized patients. Prolonged hospitalization, long-term antibiotic use and severe underlying diseases increase the risk of VRE colonization. Routine VRE surveillance of high-risk group patients is crucial for early detection and implementation of precautions to impede the development of infection and spread of VRE. The aim of this study was to evaluate the status of VRE colonization in Oncology Department of Gaziantep Children's Hospital, Turkey, following a VRE isolation from the urine sample of a patient (index case). In the first phase of this point prevalence study VRE screening was done after positive VRE result was obtained from the index case, and in the second phase VRE colonization rate was investigated after the implementation of infection control policies. Perirectal swab samples collected from patients were cultivated into supplemented VRE agar base (Oxoid, UK) including vancomycin 6 µg/ml and 5% sheep blood agar. The isolates were identified by conventional methods together with API 20 Strep (bioMerieux, France) and VITEK2 (bioMerieux, France) identification systems. Vancomycin (30 µg) and teicoplanin (30 µg) susceptibilities of the isolates were investigated by Kirby-Bauer disc diffusion method according to CLSI criteria. In addition, VITEK2 antibiogram cards, AST-592 were used to determine antibiotic susceptibilities. In the first phase of the surveillance a total of 123 perirectal swab specimens obtained from patients staying at oncology, burn, pediatric surgery and intensive care units (ICU) were investigated and the rate of VRE colonization was determined as 14.6% (18/123). Thirteen of the VRE colonized patients were from oncology wards and five were from ICU. Upon the detection of VRE colonization, contact isolation was implemented and hospital staff was educated for hand washing and restricted antibotic use policies were established. To evaluate the efficacy of infection control implementations, perirectal swab samples were collected from 242 patients under antibiotic treatment and hospitalized in several wards and ICU for ≥ 3 days. The results of this second control surveillance revealed that VRE colonization rate declined to 3.3% (8/242), and three of these VRE colonized patients were in the ICU, three in the oncology ward and one of each in burn and pediatric wards. During the study period blood stream infection developed in three of the previously colonized oncology patients of whom one patient also had simultaneous pneumoniae due to VRE. The results of this study indicated the importance of VRE surveillance at the hospital setting. The determination of the VRE colonization in the hospital will help the implementation of appropriate infection control measures and eventually decrease the rate of nosocomial VRE infection.