Class of 2017 Abstract / Objectives: The objective of this retrospective cohort chart review was to evaluate the safety and efficacy of extended infusion beta-lactam regimens as part of treatment of acute CF pulmonary exacerbations in adults and pediatric patients. Methods: Inclusion criteria: adult and pediatric patients (age 1 month or older) with CF diagnosis who were admitted to BUMC-T for acute pulmonary CF exacerbation, and who received meropenem, imipenem, aztreonam, piperacillin-tazobactam, and or cefepime during their hospitalization (between 1/1/2011 and 10/30/2015). Exclusion criteria: pregnant women and admissions less than 24 hours. The two groups evaluated were patients receiving treatment (group 1) prior to extend infusion practices (Jan 2011 – Dec 2012) and (group 2) after implementation of extend infusion practices (Jan 2013 – Oct 2015). Data was collected from medical records using both the Sunrise Clinical Manager and EPIC electronic medical record systems. The data was then analyzed for differences in efficacy outcomes (e.g., length of hospitalization, lung function, return to baseline lung function), changes in renal and hepatic function, incidence of documented adverse drug effects, and potential factors associated with increased risk for changes in renal or hepatic function with use of extended infusion beta‐lactam regimens. Results: Pending. Efficacy outcomes: - length of hospitalization - improvement in lung function - return to baseline lung function Safety outcomes: - changes in renal and hepatic function - incidence of documented adverse drug effects - potential factors associated with increased risk for changes in renal or hepatic function Conclusions: Pending. As this study is being conducted at one academic medical center, conclusions may not be generalizable to other institutions.

Cystic fibrosis (CF) is an autosomal recessive disorder affecting 70,000 individuals worldwide. This disease is characterized by the buildup of mucus in the airways leading to chronic lung infections resulting in pulmonary failure and death in 95% of CF patients. Routine surveillance of CF pathogens using traditional microbiology culture guides management and treatment of CF patients. Molecular profiling studies have revealed emerging pathogens that may play a role in CF lung disease by either directly causing infection or upregulating the virulence factors of classic CF pathogens, such as P. aeruginosa; however, routine CF culture protocols have not been modified to detect these organisms. The goal of this study was to expand the data relevant to the use of microbiology cultures for the management and treatment of CF patients at Virginia Commonwealth University Medical Center (VCUMC) by directly selecting for emerging CF pathogens in culture. This was accomplished by developing,optimizing, and implementing an agar to select for colistin-resistant non-fermenting Gram- negative rods (NF GNRS). In addition, McKay agar and anaerobic media were utilized to recover members of the Streptococcus anginosus group (SAG) and anaerobes in CF respiratory samples. The prevalences of SAG, anaerobes, and colistin-resistant NF GNRs recovered on study media from 75 adult and pediatric CF patients at VCUMC were 17.33%, 41.33%, and 4% respectively. Approximately 62% of patients culture-positive for SAG were also infected with P. aeruginosa and 53.8% of SAG recovered in culture were from CF patients experiencing PE. These findings further support the claim that interspecies interactions among emerging and classic CF pathogens may result in periods of clinical instability or PE. Twenty-eight of the 75 patients were culture-positive for Veillonella species, with the majority of samples collected during a period of surveillance. Four colistin-resistant NF GNRs were isolated on the study media alone. The selective nature of the study media prevented the mixed respiratory flora and classic CF pathogens from overgrowing and obscuring the growth of these colistin-resistant NF GNRs. The presence and role of emerging pathogens in the CF patient population at VCUMC warrants further investigation; therefore, the routine culture protocol needs to be revised to recover and select for those organisms thought to play a role in PE and lung function decline.