Diagnosis of bacteremia in febrile neutropenic episodes in children with cancer: microbiologic and molecular approach.
Pediatr Infect Dis J. 2011 Nov;30(11):957-61
Authors: Santolaya ME, Farfán MJ, De La Maza V, Cociña M, Santelices F, Alvarez AM, Avilés CL, Becker A, O'Ryan M, Román P, Salgado C, Silva P, Topelberg S, Tordecilla J, Varas M, Villarroel M, Viviani T, Zubieta M, Torres JP
BACKGROUND: Bacterial isolation using conventional microbiologic techniques rarely surpasses 25% in children with clinical and laboratory findings indicative of an invasive bacterial infection. The aim of this study was to determine the role of real-time polymerase chain reaction (RT-PCR) from whole blood samples compared with automated blood cultures (BC) in detection of relevant microorganisms causing bacteremia in episodes of high-risk febrile neutropenia (HRFN) in children with cancer.
METHODS: Children presenting with HRFN at 6 hospitals in Santiago, Chile, were invited to participate. Blood samples were obtained at admission for BC, and at admission and 24 hours for RT-PCR targeting DNA of Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa causing bacteremia in children with HRFN.
RESULTS: A total of 177 HRFN episodes were evaluated from May 2009 to August 2010, of which 29 (16.3%) had positive BC, 9 (5%) positive for 1 of the 3 selected bacterial species: 5 for E. coli, 3 for S. aureus, and 1 for P. aeruginosa. RT-PCR detected 39 bacteria in 36 episodes (20%): 14 E. coli, 20 S. aureus, and 5 P. aeruginosa. The sensitivity, specificity, and positive and negative predictive values of RT-PCR compared with BC were 56%, 80%, 13%, and 97%. The final clinical diagnosis was compatible with an invasive bacterial infection in 30/36 (83%) RT-PCR-positive episodes.
CONCLUSIONS: In our series, RT-PCR significantly improved detection of the most relevant bacteria associated with HRFN episodes. Large number of patients and close clinical monitoring, in addition to improved RT-PCR techniques will be required to fully recommend RT-PCR-based diagnosis for the routine workup of children with cancer, fever, and neutropenia.
PMID: 21768922 [PubMed - indexed for MEDLINE]