Search

Background Studies show a rising annual incidence of severe sepsis, with bloodstream infections continuing to impact children. Rapid identification of causative agents and timely administration of targeted therapy can positively impact patient outcomes and improve antibiotic stewardship. The BioFire® Blood Culture Identification 2 (BCID2) Panel (BioFire Diagnostics, LLC), an updated version of the FDA-cleared BioFire® FilmArray® Blood Culture Identification (BCID) Panel, designed for use on positive blood cultures (PBCs), assesses 43 analytes, including 17 novel analytes (8 bacterial, 2 fungal, and 7 antimicrobial resistance genes), with a similar turnaround time. Methods De-identified residual PBCs for which clinician-ordered testing per standard of care (SoC) had been performed were enrolled and tested with an Investigation-Use-Only version of the BCID2 Panel. Only one positive bottle per patient was enrolled. Results of BCID2 and BCID were compared. Results 116 PBCs (48 aerobic and 68 anaerobic) were evaluated using the BioFire BCID2 Panel and results were compared to the BioFire BCID Panel. Of the 116 cases, 103 were positive on both the BioFire BCID2 Panel and the BioFire BCID Panel. Ten cases were negative on both tests. While the two panels showed 97% agreement, three cases were discrepant. Using culture (SoC) as the tiebreaker, two cases were false positive and one case was false negative on the BioFire BCID Panel. In all three cases, results from culture and the BioFire BCID2 Panel were in agreement. As expected, no organisms were detected on the BioFire BCID2 Panel in PBCs from 10% (12/116) of PBC bottles where culture identified only organisms that are not part of the panel menu. With the BioFire BCID2 Panel’s expanded platform, two cases identified as Enterobacteriaceae on the BioFire BCID Panel were identified to the genus level on the BioFire BCID2 Panel; 31 cases detected to the genus level on the BioFire BCID Panel were identified to the species level on the BioFire BCID2 Panel. Conclusion Overall, the BioFire BCID2 Panel performed well against the BioFire BCID Panel for identification of bloodstream pathogens and provided additional discrimination of some pathogens to the genus or species level. Data presented are from assays that have not been cleared or approved for diagnostic use. Disclosures All Authors: No reported disclosures

BackgroundInvasive Staphylococcus aureus infections are a common cause of morbidity and mortality in children. In the early 2000's the proportion of infections due the methicillin-resistant S. aureus (MRSA) increased rapidly. We described the clinical and molecular epidemiology of invasive S. aureus disease in a pediatric population.MethodsWe prospectively identified children in Utah with invasive S. aureus infections. Medical records were reviewed to determine diagnosis and clinical characteristics. Isolates were genotyped using multi-locus sequence typing. The presence of genes encoding the Panton-Valentine leukocidin (PVL) was determined using polymerase chain reaction.ResultsOver a 4-year period between January 2009 and December 2012, we identified 357 children, hospitalized at Primary Children's Hospital, with invasive S. aureus infections and isolates available for the study. Methicillin-susceptible S. aureus (MSSA) caused 79% of disease, while MRSA caused only 21% of disease. Mortality associated with invasive S. aureus infection was 3.6%. The most common diagnoses were osteoarticular infections (38%) followed by central line associated blood stream infections (19%) and pneumonia (12%). We identified 41 multi-locus sequence types. The majority of isolates belonged to 6 predominant clonal complexes (CC5, CC8, CC15, CC30, CC45, CC59). PVL was present in a minority (16%) of isolates, of which most were ST8 MRSA.ConclusionsMSSA was the primary cause of invasive S. aureus infections at our institution throughout the study period. A limited number of predominant strains accounted for the majority of invasive disease. The classic virulence factor PVL was uncommon in MSSA isolates. Further study is needed to improve our understanding of S. aureus virulence and disease pathogenesis.

Background Following widespread use of the Haemophilus influenzae serotype b (Hib) vaccine, H. influenzae serotype a (Hia) has emerged as an important pathogen in children in some regions. We describe the clinical features and molecular epidemiology of invasive Hia disease in children in Utah over an 11-year period. Methods We identified cases of invasive Hia disease, defined as detection of Hia from a normally sterile site, in children aged Results We identified 51 children with invasive Hia. The average annual incidence was 1.7 cases per 100 000 children aged Conclusions Hia is a significant cause of severe invasive bacterial infection in Utah. The majority of infections were caused by ST62 isolates, a phylogenetic division II Hia type that lacks the IS1016-bexA duplication-deletion. Hia ST62 has not been commonly reported elsewhere, suggesting a unique molecular epidemiology in our population.

Background Following widespread use of the Haemophilus influenzaeserotype b (Hib) vaccine,H. influenzae serotype a (Hia) has emerged as an important pathogen in children. Rates of Hia disease are particularly high in Utah. We describe the clinical features and molecular epidemiology of invasive Hia disease in children in Utah over 11 years. Methods Cases of invasive Hia disease in children less than 18 years were identified through electronic clinical and microbiology records. Demographic data and clinical outcomes were abstracted from the medical record for all cases. Available Hia isolates were collected for molecular analysis. Isolates were genotyped by multi-locus sequence typing (MLST) and clonal division was determined using sodC PCR. Presence or absence of the putative virulence-associated IS1016-bexA duplication-deletion was evaluated. Results We identified 51 children with invasive Hia between 2007 and 2017. Median age was 11.3 months. The average annual incidence was 1.7 cases per 100,000 children aged Conclusion Hia is an important cause of severe invasive bacterial infection in Utah. Molecular analyses revealed that a majority of infections were caused by ST62 isolates, a clonal division II Hia type lacking the IS1016-bexA duplication-deletion. Hia ST62 has not been commonly reported in other settings, suggesting a unique molecular epidemiology in our population. Disclosures All authors: No reported disclosures.

Background Early targeted antibiotic therapy is crucial when treating pediatric patients with bacteremia. While identification (ID) and antimicrobial susceptibility testing (AST) of bloodstream pathogens are critical to optimizing therapy, conventional methods can take days resulting in inappropriate use of broad-spectrum antibiotics. The automated Accelerate Pheno™ system (AXDX) provides ID in