180. Duration of Therapy and Clinical Outcomes in Adult Oncology Patients with Uncomplicated Coagulase Negative Staphylococcal Bacteremia

Background Although they are often considered contaminants, coagulase negative staphylococci (CoNS) can be pathogens especially in immunocompromised patients. National and local guidelines recommend treatment durations of 7 to 14 days, depending on specific clinical scenarios. The objective was to characterize the duration of treatment for CoNS bacteremia and clinical outcomes at our cancer center. Methods We conducted a retrospective chart review of adult patients ≥18 years old with ≥1 blood culture with growth of CoNS between 1/1/17 and 12/31/19 at our cancer center. Patients with complicated CoNS bacteremia and polymicrobial infections were excluded. Results Among 128 patients identified during the study period, 98 met inclusion criteria (Figure 1). Most patients (N= 92; 94%) had a hematologic malignancy as the underlying oncologic diagnosis, and 68 (69%) were hematopoietic stem cell transplant recipients. The median total antibiotic duration was 13 days, and median duration from the date of 1st negative blood culture was 12 days; 29 (30%) patients were treated for a total duration of >14 days (Figure 2). The catheter was retained in 67 (68%) and exchanged in 4 (4%) of the cases. Three (3%) patients had recurrence of bacteremia within 30 days of treatment completion, and 8 (8%) patients were transferred to the ICU within 7 days of the index blood culture. The 30-day crude mortality rate was 10%. The most commonly used antibiotic for treatment was vancomycin (N= 95; 97%), and 32 (34%) patients on vancomycin had an increase in serum creatinine of ≥ 50% from baseline. Five (5%) patients discontinued vancomycin due to nephrotoxicity, and 4 (4%) patients required hemodialysis. Figure 1. Results Overview Among 128 patients identified during the study period, 98 met inclusion criteria. Of those included, 36 had one set of blood cultures that were positive for CoNS and 62 patients had at least two sets of blood cultures that were positive for CoNS. Figure 2. Duration of Antibiotic Treatment We evaluated duration of treatment based on total antibiotic duration and duration from date of 1st negative blood culture. The number of patients is noted above each bar. Conclusion Although the majority of patients were treated for ≤14 days for uncomplicated CoNS bacteremia, nearly 1/3 of patients were treated for > 14 days. Recurrent bacteremia was uncommon despite catheter retention in most patients. Relatively high rates of vancomycin associated nephrotoxicity highlight opportunities for antimicrobial stewardship to limit duration of vancomycin therapy among cancer patients with uncomplicated CoNS bacteremia. Disclosures All Authors: No reported disclosures

Impact of Pharmacist Involvement on the Utility of a Gram-Negative Blood Culture Identification Panel on Antimicrobial Usage

Background: A rapid molecular diagnostic test (MDT) is a test used to identify several different species of gram-negative bacteria and their genetic resistance markers. However, the impact of rapid MDT has not been established when combined with pharmacist involvement. Objective: To determine the impact of pharmacy involvement on patient outcomes when using rapid MDT. The primary outcome is the time from gram stain result to the first dose of the targeted antibiotic. Methods: This is a single-center, quasi-experimental, 1-group pretest-posttest design study of patients with gram-negative bacteremia in a community hospital. Hospitalized patients 18 years or older were included if they had a gram-negative blood culture. Patients were excluded if they were discharged or expired prior to culture results. Outcomes were compared between patients prior to and after implementation of the automated MDT. This research was determined to be exempt from institutional review board oversight consistent with West Florida Healthcare and in accordance with institutional policy. Results: The use of rapid MDT combined with pharmacist intervention resulted in a statistically significant decrease in the time to targeted antibiotic therapy (pre-intervention group, n = 77, 44.8 ± 17.8 hours versus post-intervention group, n= 80, 4.4 ± 5.8 hours; P ≤.001). There was no significant difference found between secondary outcomes. Limitations included small sample size as well as inconsistent documentation. Conclusions: The use of rapid MDT combined with pharmacist intervention resulted in a statistically significant decrease in the time to targeted antibiotic therapy.

Study of procalcitonin in neonatal sepsis with blood culture in suspected sepsis in North India

Background: Sepsis can occasionally be difficult to demonstrate, and its difference from non-infectious conditions in critically ill patients is often a challenge. Serum procalcitonin (PCT) assay is one of the biomarkers of sepsis. The aim of the study was to investigate the value of procalcitonin, in the early diagnosis of neonatal sepsis.Methods: A cross-sectional study was conducted at tertiary care hospital in New Delhi. It included all neonates with clinical signs of sepsis. The neonates were divided into two groups as sepsis, and healthy neonates. The PCT level was measured by using ELISA technique and compared between the two groups. Statistical analysis was performed using SPSS windows version 20.0 software.Results: In this study total number of patients included 350, out of which 175 were clinically suspected sepsis cases and 175 were healthy controls. 68 (39%) neonates were show positive blood culture and 107 (61%) neonates were representing negative blood culture report in study group. The mean serum value of PCT was significantly (p<0.001) higher in sepsis neonates. The serum PCT value was significantly increased in neonate’s sepsis with positive blood culture (p<0.001) and negative blood culture (p<0.001) as compared to healthy neonates.Conclusions: It is concluded from this study that the PCT assay was established to be a valuable biomarker of sepsis in this study. The assay might be performed and reported quickly and gave precious information before availability of culture results. This might assist in avoiding unnecessary antibiotic therapy.

[18F]FDG hypermetabolisms of the spleen and/or bone marrow: indirect signs of bacteremia

Funding Acknowledgements Type of funding sources: None. Aim Recently hypermetabolisms of the spleen and/or bone marrow has been proposed as an indirect sign of infective endocarditis (IE), useful to reinforce the suspicion of IE in the absence of any other infectious, inflammatory, or malignant disease. The purpose of this study is to determine whether hypermetabolisms of the spleen and/or bone marrow are indirect signs of bacteremia rather than of IE, specifically. Materials and Method In this work we retrospectively evaluated a series 240 patients who performed between January 2015 to December 2020 [18F]FDG PET/CT (Discovery 710 GE) for suspected infection. In particular, 80 pts had infections from different origin and a positive blood culture (PBC), 80 pts presented localized infection, but negative blood culture (IDBCN) and 80 pts were classified as definite IE (IED) according to the 2015 ESCcriteria. [18F]FDG SUVmax SUVmean in bone marrow, spleen and liver were measured drawind a 14 cm3 regions of interest (ROIs) positioned close to the centers of the spleen and of the right liver lobe, but excluding abscess and/or ischemic lesions., as previously described (Caroline Boursier et al. ; Jordy P.Pijl et al.). BM SUVmax and SUVmean was obtained from ROIs placed on the bodies of each of the five lumbar vertebrae, excluding any damaged vertebra. BM to liver SUV ratios (BLR) and spleen to liver SUV ratios (SLR) were calculated. Kruskal-Wallis tests and the Dunn’s test procedure for multiple comparison were performed using JMP Statistical Discoverytm. Results No significant difference among the three groups of SUVmax/mean or in SLR were found. Nevertheless, by grouping patients for the presence of positive blood culture (142 pts) or negative blood culture (98 pts), irrespectively from the final diagnosis a significant associations of SLR was found (p = 0.0070). No significant associations were found with BLR. Conclusions Based on our data SLR in seems to represent an indirect signs of bacteremia, rather than IE.

The Association between Prolonged Antibiotic Use in Culture Negative Infants and Length of Hospital Stay and Total Hospital Costs

Objective This study aimed to determine if prolonged antibiotic use at birth in neonates with a negative blood culture increases the total cost of hospital stay. Study design This was a retrospective study performed at a 60-bed level IV neonatal intensive care unit. Neonates born <30 weeks of gestation or <1,500 g between 2016 and 2018 who received antibiotics were included. A multivariate linear regression analysis was conducted to determine if clinical factors contributed to increased hospital cost or length of stay. Results In total, 190 patients met inclusion criteria with 94 infants in the prolonged antibiotic group and 96 in the control group. Prolonged antibiotic use was associated with an increase length of hospital stay of approximately 31.87 days, resulting in a $69,946 increase in total cost of hospitalization. Conclusion Prolonged antibiotics in neonates with negative blood culture were associated with significantly longer hospital length of stay and increased total cost of hospitalization. Key Points

Characteristics of spirochetemic patients with a solitary erythema migrans skin lesion in Europe

Neither pre-treatment characteristics, nor the outcome after antibiotic therapy, have been reported for spirochetemic European patients with Lyme borreliosis. In the present study, patients with a solitary erythema migrans (EM) who had a positive blood culture for either Borrelia afzelii (n = 116) or Borrelia garinii (n = 37) were compared with age- and sex-matched patients who had a negative blood culture, but were culture positive for the corresponding Borrelia species from skin. Collectively, spirochetemic patients significantly more often recalled a tick bite at the site of the EM skin lesion, had a shorter time interval from the bite to the onset of EM, had a shorter duration of the skin lesion prior to diagnosis, and had a smaller EM skin lesion that was more often homogeneous in appearance. Similar results were found for the subset of spirochetemic patients infected with B. afzelii but not for those infected with B. garinii. However, patients with B. garinii bacteremia had faster-spreading and larger EM skin lesions, and more often reported itching at the site of the lesion than patients with B. afzelii bacteremia. Treatment failures were rare (7/306 patients, 2.3%) and were not associated with having spirochetemia or with which Borrelia species was causing the infection.

Comparing mortality between positive and negative blood culture results: an inverse probability of treatment weighting analysis of a multicenter cohort

Background The association between blood culture status and mortality among sepsis patients remains controversial hence we conducted a tri-center retrospective cohort study to compare the early and late mortality of culture-negative versus culture-positive sepsis using the inverse probability of treatment weighting (IPTW) method. Methods Adult patients with suspected sepsis who completed the blood culture and procalcitonin tests in the emergency department or hospital floor were eligible for inclusion. Early mortality was defined as 30-day mortality, and late mortality was defined as 30- to 90-day mortality. IPTW was calculated from propensity score and was employed to create two equal-sized hypothetical cohorts with similar covariates for outcome comparison. Results A total of 1405 patients met the inclusion criteria, of which 216 (15.4%) yielded positive culture results and 46 (21.3%) died before hospital discharge. The propensity score model showed that diabetes mellitus, urinary tract infection, and hepatobiliary infection were independently associated with positive blood culture results. There was no significant difference in early mortality between patients with positive or negative blood culture results. However, culture-positive patients had increased late mortality as compared with culture-negative patients in the full cohort (IPTW-OR, 1.95, 95%CI: 1.14–3.32) and in patients with severe sepsis or septic shock (IPTW-OR, 1.92, 95%CI: 1.10–3.33). After excluding Staphylococcal bacteremia patients, late mortality difference became nonsignificant (IPTW-OR, 1.78, 95%CI: 0.87–3.62). Conclusions Culture-positive sepsis patients had comparable early mortality but worse late mortality than culture-negative sepsis patients in this cohort. Persistent Staphylococcal bacteremia may have contributed to the increased late mortality.

Clinical consequences of contaminated blood cultures in adult hospitalized patients at an institution utilizing a rapid blood-culture identification system

Objective: To assess the clinical impact of contaminated blood cultures in hospitalized patients during a period when rapid diagnostic testing using a FilmArray Blood Culture Identification (BCID) panel was in use. Design: Retrospective cohort study. Setting: Single academic medical center. Participants: Patients who had blood culture(s) performed during an admission between June 2014 and December 2016. Methods: Length of hospital stay and days of antibiotic therapy were assessed in relation to blood-culture contamination using generalized linear models with univariable and multivariable analyses. Results: Among 11,474 patients who had blood cultures performed, the adjusted mean length of hospital stay for patients with contaminated blood-culture episodes (N = 464) was 12.3 days (95% confidence interval [CI], 11.4–13.2) compared to 11.5 days (95% CI, 11.0–11.9) for patients (N = 11,010) with negative blood-culture episodes (P = .032). The adjusted mean durations of antibiotic therapy for patients with contaminated and negative blood-culture episodes were 6.0 days (95% CI, 5.3–6.7) and 5.2 days (95% CI, 4.9–5.4), respectively (P = .011). Conclusions: Despite the use of molecular-based, rapid blood-culture identification, contamination of blood cultures continues to result in prolonged hospital stay and unnecessary antibiotic therapy in hospitalized patients.

293. Influence of a Pharmacist Led Treatment Algorithm for the Management of Staphylococcus Bacteremia

Background Staphylococcus bacteremia is a major healthcare burden and currently there is no widely recommended treatment algorithm. Our institution adopts all elements of antimicrobial stewardship including rapid diagnostic testing. Despite these efforts, management of staphylococcus bacteremia continues to be problematic. The objective of this project is to evaluate implementation of a pharmacist-driven algorithm to guide treatment selection for staphylococcus bacteremia. Methods This is a single center, IRB-approved cohort study with a retrospective and prospective phase. The algorithm was designed in collaboration with the infectious disease (ID) service. Retrospective data was collected from June 2019 through September 2019. The algorithm was implemented on October 1, 2019 and prospective data was collected through January 2020. Prospectively a pharmacy resident identified positive blood cultures and recommended treatment based on the algorithm. Patients 18 years of age or older with a positive blood culture for staphylococcus were included. Patients were excluded if treatment was initiated at an outside hospital. The primary outcome is algorithm adherence. Secondary outcomes include days to negative blood culture, days to de-escalation, length of hospital stay and whether ID was consulted. Treatment Algorithm Results A total of 64 patients were identified in the retrospective cohort and 46 in the intervention group. There were no significant differences in baseline characteristics. Algorithm adherence increased from 45% to 72% upon implementation (p=0.006). The algorithm resulted in a shorter time to de-escalation from 2.1 to 1.3 days (p=0.04). There were no statistically significant differences in days to negative blood culture, 2.3 vs. 2.2 days, or in average length of stay, 12.1 vs. 10.6 days in the retrospective and intervention groups, respectively. ID was consulted on 50% of patients in the retrospective cohort and 48% in the intervention group. Conclusion Implementation of a staphylococcus bacteremia treatment algorithm optimizes management. Additional layers of pharmacy involvement also result in a shorter time to de-escalation. These results highlight the importance of continuity of antimicrobial stewardship efforts. Disclosures All Authors: No reported disclosures