Author Affiliations: Mansoura University Children's Hospital, Hematology and Oncology Unit (Al-Tonbary YA, Sarhan MM, El-Ashry RA, El-Sharkawy AA), Unit of Infectious Diseases (Soliman OE, Hegazi MA), Clinical Pathology Department (Salama OS, Yahya R), Mansoura University, Egypt

Corresponding Author: Prof. Youssef Al-Tonbary, Mansoura University Children's Hospital, Mansoura, Egypt (Tel: +20123165302; Fax: +20502262307; Email: ytonbary@gmail.com)

Background: Pediatric hematology/oncology patients are faced with an increased risk of nosocomial infections (NIs) that vary in different populations and different institutions with considerable morbidity and mortality. This study was undertaken to assess the frequency and patterns of NIs in 1564 pediatric patients and to determine the prevalence of causative organisms and their antimicrobial sensitivity.

Methods: A retrospective analysis was made in the patients admitted between January 2007 and January 2008 to the pediatric hematoloy/oncology unit of Mansoura University, Egypt. The 1564 patients showed 2084 admissions and 27 092 inpatient days. The Centers for Disease Control and Prevention criteria were used as a standard definition for NI.

Results: The overall rate of NIs in all patients and neutropenic patients was 8.6 and 25.3 per 1000 patient-days respectively. The frequent sites of NIs were blood stream (42.7%), the respiratory system (25.3%), the urinary system (22.2%) and the central nervous system (9.8%), whereas nosocomial fever of unknown origin constituted 52.9% of cases. The incidence of NIs was significantly higher during neutropenic days (P<0.001). Gram-positive organisms represented 64.5% of pathogens (Staphylococci 71.5%, Streptococci 16%, and pneumococci 7%), and Gram-negative organisms represented 30% (E. coli 48.6%, Klebsiella 15.7%, Pseudomonas 35.7%, and C. albicans 5.5%). Positive cultures were more frequent in summer (July to September). Susceptibility of isolated organisms was relatively low (cefoperazone/sulbactam 49.9%, amikacin 35.9%, imipenem/cilastin 34.4%, cefoperazone 33.6%, and vancomycin 36.5%). Methicillin-resistant S. aureus, extended spectrum beta lactamase and vancomycin resistant enterococci represented 30%, 45% and 75% of isolated S. aureus, Gram-negative organisms and Enterococci, respectively.

Conclusions: Blood stream infection and fever of unknown origin are the most common nosocomial infections in pediatric hematology/oncology patients with a higher risk during neutropenic days. Isolated organisms are multi-drug resistant, predominantly Gram-positive pathogens with a high incidence of methicillin-resistant S. aureus, extended spectrum beta lactamase and vancomycin resistant enterococci organisms.

Key words: fever of unknown origin; hematology/oncology; nosocomial infections;  pediatric