A Case of Bacteremia Caused by Raoultella planticola Direct Identification from Blood Culture by Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry.

Background: Raoultella planticola is an uncommon gram-negative organism found in the environment. Patients and Methods: The patient, an 81-year-old female who had undergone total cystectomy and bilateral ureteral stoma surgery, presented to the hospital with a fever. It was determined that Raoultella planticola was responsible for the bacteremia. Results: Rapid identification of bacteria using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) in blood culture samples and appropriate antibacterial treatment was begun and the patient was discharged three days later. Conclusions: This case emphasizes the presence of a rare pathogen as the cause of bacteremia and underscores the importance of utilizing rapid methods for bacterial identification to establish an accurate diagnosis.

Hemocultivos contaminados: bundle para lograr proporciones aceptables / Blood cultures contaminated: bundle to achieve acceptable proportions

Introducción. El problema de la contaminación de los hemocultivos es muy frecuente en establecimientos de atención hospitalaria, da lugar a la administración de antibióticos innecesarios y prolonga la hospitalización. Objetivo principal. Aplicar un bundle para reducir la proporción de contaminación de hemocultivos. Objetivo secundario. Realizar una encuesta anónima para detectar oportunidades de mejora en la técnica de extracción de hemocultivos. Metodología. Diseño del estudio: Estudio cuasi experimental que evaluó la proporción de contaminación de hemocultivos antes y después de implementar un bundle propio. Se determinó la proporción basal de contaminación de hemocultivos (ene-jul 2022), se realizó la intervención (agosto 2022) y se estableció la proporción de contaminación post intervención (sep.-abril 2023). Intervención: Se analizó la estructura, procedimiento y conocimiento del personal mediante una encuesta propia para detectar áreas de mejora. Se capacitó, a los técnicos de laboratorio, sobre el procedimiento de la toma de muestra mediante una simulación utilizando un brazo artificial. Se diseñó un bundle de seis medidas, se adaptó el procedimiento de toma de hemocultivo y se capacitó al personal. Análisis estadístico. Se analizó la proporción de hemocultivos contaminados entre los periodos pre y post utilizando Chi2 y la relación entre la proporción del periodo pre y post vs la literatura (3.00% contaminación aceptable) utilizando test Z para una proporción. Se consideró un p<0.05 como estadísticamente significativa. Se utilizo el software Stata 8. Resultados. Durante el estudio se analizaron un total de 3,965 hemocultivos. De estos, 1,978 corresponden al periodo pre-intervención y 1,987 corresponden al periodo post intervención. Durante la pre-intervención se detectaron 61 hemocultivos contaminados (3.08% vs 3.00% bibliografía, p:0.5866) mientras que en la etapa post intervención fue de 30 hemocultivos contaminados (1.51% vs 3.00% bibliografía, p:0.0000). La proporción de hemocultivos contaminados se redujo a la mitad, 3.08% vs 1.51%, p: 0.001. Se realizó una encuesta anónima pre y post intervención logrando mejoras en la técnica de toma de hemocultivos. Conclusión. La implementación del bundle propio para la extracción de hemocultivos, permitió reducir la proporción de contaminación a la mitad. El análisis de la encuesta nos permitió identificar oportunidades de mejora en la técnica de recolección de muestra de hemocultivos

Introduction: Contamination of blood cultures is very common in hospital care settings and results in the administration of unnecessary antibiotics and prolongs hospitalization. Main goal: Apply a bundle to reduce the rate of contamination of blood cultures. Secondary objective: Conduct an anonymous survey to detect opportunities for improvement in the blood culture extraction technique. Methodology: Study design: Quasi-experimental study that evaluated the proportion of blood culture contamination before and after implementing its own bundle. The baseline proportion of blood culture contamination was determined (Jan-July 2022), the intervention was performed (August 2022) and the post-intervention contamination proportion was established (September-April 2023). Intervention: The structure, procedure and knowledge of the staff was analyzed through an own survey to detect areas for improvement. Laboratory technicians were trained on the sample collection procedure through a simulation using an artificial arm. A bundle of six measures was designed: (hand hygiene with alcohol gel, use of common gloves and sterile gloves during extraction, antisepsis with alcoholic chlorhexidine gluconate, marking of the blood culture bottle up to the filling level, disinfection of the bottle cap). blood culture bottle with 70% alcohol, safety-lok kit with vacuum extraction system). The procedure was adapted and staff trained. Statistic analysis: The proportion of contaminated blood cultures between the pre and post periods was analyzed using Chi2 and the relationship between the proportion of the pre and post period vs the literature (3.00% acceptable contamination) using Z test for a proportion. P<0.05 was considered statistically significant. Stata 8 software was used.Results: A total of 3,965 blood cultures were analyzed during the study. Of these, 1,978 correspond to the pre-intervention period and 1,987 correspond to the post-intervention period. During the pre-intervention, 61 contaminated blood cultures were detected (3.08%) while in the post-intervention stage there were 30 contaminated blood cultures (1.51%). The proportion of contaminated blood cultures was reduced by half, 3.08% vs 1.51%, p: 0.001. An anonymous survey was carried out pre and post intervention, achieving improvements in the technique of taking blood cultures. Conclusion: The implementation of the own bundle for the extraction of blood cultures allowed the contamination rate to be reduced by ha

Changes in clinical parameters and inflammatory markers after blood culture collection facilitate early identification of positive culture in adult patients with COVID-19 and clinically suspected bloodstream infection.

OBJECTIVE: We explored whether changes in clinical parameters and inflammatory markers can facilitate early identification of positive blood culture in adult patients with COVID-19 and clinically suspected bloodstream infection (BSI). METHODS: This single-center retrospective study enrolled 20 adult patients with COVID-19 admitted to the intensive care unit who underwent blood culture for clinically suspected BSI (February 2020-November 2021). We divided patients into positive (Pos) and negative blood culture groups. Clinical parameters and inflammatory markers were obtained from medical records between blood culture collection and the first positive or negative result and compared between groups on different days. RESULTS: Patients in the positive culture group had significantly older age and higher D-dimer, immunoglobulin 6 (IL-6), and Sequential Organ Failure Assessment score as well as lower albumin (ALB). The area under the receiver operating characteristic curve (AUC) was 0.865 for IL-6, D-dimer and ALB on the first day after blood culture collection; the AUC was 0.979 for IL-6, IL-10, D-dimer, and C-reactive protein on the second day after blood culture collection. CONCLUSION: Changes in clinical parameters and inflammatory markers after blood culture collection may facilitate early identification of positive culture in adult patients with COVID-19 and clinically suspected BSI.

[Usefulness of the MPB-INFURG-SEMES model to predict bacteremia in the patient with solid tumor in the Emergency Department]. / Utilidad del modelo MPB-INFURG-SEMES para predecir bacteriemia en el paciente con neoplasia sólida en el Servicio de Urgencias.

OBJECTIVE: To analyse a new risk score to predict bacteremia (MPB-INFURG-SEMES) in the patients with solid tumor attender for infection in the emergency departments (ED). METHODS: Prospective, multicenter observational cohort study of blood cultures (BC) obtained from adult patients with solid neoplasia treated in 63 EDs for infection from November 1, 2019, to March 31, 2020. The predictive ability of the model was analyzed with the area under the Receiver Operating Characteristic curve (AUC-ROC). The prognostic performance for true bacteremia was calculated with the chosen cut-off for getting the sensitivity, specificity, positive predictive value and negative predictive value. RESULTS: A total of 857 blood samples wered cultured. True cases of bacteremia were confirmed in 196 (22.9%). The remaining 661 cultures (77.1%) wered negative. And, 42 (4.9%) were judged to be contaminated. The model's area under the receiver operating characteristic curve was 0.923 (95% CI,0.896-0.950). The prognostic performance with a model's cut-off value of ≥ 5 points achieved 95.74% (95% CI, 94,92-96.56) sensitivity, 76.06% (95% CI, 75.24-76.88) specificity, 53.42%(95% CI, 52.60-54.24) positive predictive value and 98.48% (95% CI, 97.66- 99.30) negative predictive value. CONCLUSIONS: The MPB-INFURG-SEMES score is useful for predicting bacteremia in the adults patients with solid tumor seen in the ED.

Isolation and identification of Wickerhamiella tropicalis from blood culture by MALDI-MS.

Wickerhamiella is a genus of budding yeast that is mainly isolated from environmental samples, and 40 species have been detected. The yeast isolated from human clinical samples usually only contain three species: W. infanticola, W. pararugosa and W. sorbophila. In this study, we isolated W. tropicalis from a blood sample of a six-year-old female with a history of B-cell precursor lymphoblastic leukemia in Japan in 2022. Though the strain was morphologically identified as Candida species by routine microbiological examinations, it was subsequently identified as W. tropicalis by sequencing the internal transcribed spacer (ITS) of ribosomal DNA (rDNA). The isolate had amino acid substitutions in ERG11 and FKS1 associated with azole and echinocandin resistance, respectively, in Candida species and showed intermediate-resistant to fluconazole and micafungin. The patient was successfully treated with micafungin. Furthermore, matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) detected three novel peaks that are specific for W. tropicalis, indicating that MALDI-MS analysis is useful for rapid detection of Wickerhamiella species in routine microbiological examinations.

Plasma Microbial Cell-Free DNA Sequencing for Pathogen Detection and Quantification in Children With Musculoskeletal Infections.

BACKGROUND: Nearly half of all pediatric musculoskeletal infections (MSKIs) are culture negative. Plasma microbial cell-free DNA (mcfDNA) sequencing is noninvasive and not prone to the barriers of culture. We evaluated the performance of plasma mcfDNA sequencing in identifying a pathogen, and examined the duration of pathogen detection in children with MSKIs. METHODS: We conducted a prospective study of children, aged 6 months to 18 years, hospitalized from July 2019 to May 2022 with MSKIs, in whom we obtained serial plasma mcfDNA sequencing samples and compared the results with cultures. RESULTS: A pathogen was recovered by culture in 23 of 34 (68%) participants, and by initial mcfDNA sequencing in 25 of 31 (81%) participants. Multiple pathogens were detected in the majority (56%) of positive initial samples. Complete concordance with culture (all organisms accounted for by both methods) was 32%, partial concordance (at least one of the same organism(s) identified by both methods) was 36%, and discordance was 32%. mcfDNA sequencing was more likely to show concordance (complete or partial) if obtained prior to a surgical procedure (82%), compared with after (20%), (RR 4.12 [95% CI 1.25, 22.93], p = .02). There was no difference in concordance based on timing of antibiotics (presample antibiotics 60% vs no antibiotics 75%, RR 0.8 [95% CI 0.40, 1.46], p = .65]). mcfDNA sequencing was positive in 67% of culture-negative infections and detected a pathogen for a longer interval than blood culture (median 2 days [IQR 1, 6 days] vs 1 day [1, 1 day], p < .01). CONCLUSIONS: Plasma mcfDNA sequencing may be useful in culture-negative pediatric MSKIs if the sample is obtained prior to surgery. However, results must be interpreted in the appropriate clinical context as multiple pathogens are frequently detected supporting the need for diagnostic stewardship.

Cytokine expression in subjects with Mycobacterium avium ssp. paratuberculosis positive blood cultures and a meta-analysis of cytokine expression in Crohn's disease.

Objectives: 1) Culture Mycobacterium avium ssp. paratuberculosis (MAP)from blood, 2) assess infection persistence, 3) determine Crohn's disease (CD) cytokine expression, 4) compare CD cytokine expression to tuberculosis, and 5) perform a meta-analysis of cytokine expression in CD. Methods: The Temple University/Abilene Christian University (TU/ACU) study had a prospective case control design with 201 subjects including 61 CD patients and 140 non-CD controls. The culture methods included MGIT, TiKa and Pozzato broths, and were deemed MAP positive, if IS900 PCR positive. A phage amplification assay was also performed to detect MAP. Cytokine analysis of the TU/ACU samples was performed using Simple Plex cytokine reagents on the Ella ELISA system. Statistical analyses were done after log transformation using the R software package. The meta-analysis combined three studies. Results: Most subjects had MAP positive blood cultures by one or more methods in 3 laboratories. In our cytokine study comparing CD to non-CD controls, IL-17, IFNγ and TNFα were significantly increased in CD, but IL-2, IL-5, IL-10 and GM-CSF were not increased. In the meta-analysis, IL-6, IL-8 and IL-12 were significantly increased in the CD patients. Conclusion: Most subjects in our sample had MAP infection and 8 of 9 subjects remained MAP positive one year later indicating persistent infection. While not identical, cytokine expression patterns in MAP culture positive CD patients in the TU/ACU study showed similarities (increased IL-17, IFNγ and TNFα) to patterns of patients with Tuberculosis in other studies, indicating the possibilities of similar mechanisms of pathogen infection and potential strategies for treatment.

Improving diagnostic accuracy of blood culture-positive cases in a cancer center via an antimicrobial stewardship program and infectious disease consultations.

The direct impact of antimicrobial stewardship programs (ASP) and infectious disease (ID) consultations on patients' clinical diagnoses remains unknown. We assessed their influence on improving the diagnostic accuracy of blood culture-positive inpatients at a Japanese cancer center. Our single-center, retrospective observational study was conducted from April 1, 2018 to March 31, 2022 to evaluate two phases: pre-intervention (notification of antimicrobials by the infection control team) and post-intervention (ASP implementation and ID consultation service establishment). There were 42,514 inpatients: 22,096 during the pre-intervention and 20,418 during the intervention periods. A total of 939 blood culture-positive episodes (pre-intervention, n = 434; post-intervention, n = 505) were analyzed. During the pre-intervention period, 28.1% of the patients had an unknown diagnosis, which decreased significantly to 1.2% post-intervention. Furthermore, hepatobiliary tract and other infections increased significantly post-intervention, and the mortality rate due to Staphylococcus aureus infection decreased from 28.6% pre-intervention to 10.4% post-intervention. The trend and level of the total number of culture specimens submitted per 1000 patient days for all culture specimens increased significantly post-intervention. Notably, the two-set rate of monthly blood cultures increased significantly. In conclusion, improving the overall diagnostic process with ASP and ID consultations at cancer centers could lead to the optimization of patient care.

An emergency department intervention to improve earlier detection of community-onset bloodstream infection among hospitalized patients.

BACKGROUND: Blood cultures (BCs) are essential microbiologic tests, but blood culturing diagnostic stewardship is frequently poor. We aimed to study the process-related failures and to evaluate the effect of an emergency department (ED) intervention on BCs collection practices and yield. METHODS: We implemented an ED-quality improvement intervention including educational sessions, phlebotomists addition, promoting single-site strategy for BC-collection and preanalytical data feedback. BC-bottles collected, positive BCs, blood volumes and documentation of collection times were measured, before (December 2021-August 2022) and after (September 2022-July 2023) intervention. Results were corrected to hospitalizations admissions or days. We used interrupted-time series analyses for comparisons. RESULTS: A total of 64,295 BC bottles were evaluated, 26,261 before and 38,034 postintervention. The median ED-BCs collected per week increased from 88 to 105 BCs (P < .0001), resulting from increased early sampling (P = .0001). Solitary BCs decreased (95%-28%), documented times increased (2.8%-25%), and average blood volume increased (3 mL to 4.5 mL) postintervention. Community-onset Bloodstream infections (BSIs) increased (39.6-52 bottles/1,000 admissions, P = .0001), while Health care-associated BSIs decreased (39-27 bottles/10,000 days, P = .0042). Contamination rates did not change. CONCLUSIONS: An ED-focused intervention based on the education sessions and single-site strategy improved culturing stewardship and facilitated the early identification of BSI without an increase in contamination.

Evaluating the Proportion of Low-Value Blood Cultures Obtained in a Pediatric Emergency Department.

BACKGROUND: Existing literature suggests that for some pediatric conditions, blood cultures may be of low value in specific clinical circumstances. The goals of our study were to: 1) identify common pediatric illnesses and define criteria for low-value blood cultures in children aged from 91 days to 19 years, 2) apply these criteria retrospectively to identify the patients in our emergency department (ED) who had low-value blood cultures obtained, and 3) describe this cohort and assess the proportion of true bacteremia in low-value blood cultures. METHOD: The study team reviewed the literature and developed consensus criteria to identify conditions in which blood cultures were of low value for our study population. The criteria were applied retrospectively to well-appearing patients aged from 91 days to 19 years, without a central venous catheter, and evaluated in our ED with a peripheral blood culture from June 2018 to April 2020. Children admitted to the intensive care/hematology-oncology/cardiology/pulmonary units, those transferred from our ED to an outside facility, who transferred to our ED due to a positive blood culture from an outside facility, and repeat visits of a patient within 30 days from a previous visit were excluded from the study. After chart review, children with fever for 7 days or more, who were unvaccinated, immunosuppressed, had implanted devices, had a complex medical history, or had provider concerns for bacteremia/sepsis were excluded. RESULTS: The study population consisted of 1436 children. Children at risk for bacteremia (n = 718) were excluded. Four hundred twenty-four children had discharge diagnoses not included in our study. There were 294 (20.5%) patients who had low-value cultures per our study criteria. Nine children (9/294, 3.1%) had false-positive blood cultures, and three (3/294, 1.0%) had true-positive blood cultures. CONCLUSIONS: We identified a cohort of patients in our ED with blood cultures obtained when available literature indicates they were of low value.

COMPARISON AMONG PRESEPSIN, PROCALCITONIN, AND C-REACTIVE PROTEIN IN PREDICTING BLOOD CULTURE POSITIVITY AND PATHOGEN IN SEPSIS PATIENTS.

ABSTRACT: Background: Sepsis is caused by the invasion of the bloodstream by microorganisms from local sites of infection, leading to high mortality. This study aimed to compare the predictive ability of the biomarkers presepsin, procalcitonin (PCT), and C-reactive protein for bacteraemia. Methods: In this retrospective, multicentre study, a dataset of patients with sepsis who were prospectively enrolled between November 2017 and June 2021 was analyzed. The performances of the biomarkers for predicting positive blood cultures and infection with specific pathogens were assessed by the areas under the receiver operating characteristic curves (AUCs). The independent effects of the pathogen and foci of infection on presepsin and PCT levels were assessed by linear logistic regression models. Results: A total of 577 patients with 170 positive blood cultures (29.5%) were enrolled. The AUC achieved using PCT levels (0.856) was significantly higher than that achieved using presepsin (0.786, P = 0.0200) and C-reactive protein (0.550, P < 0.0001) levels in predicting bacteraemia. The combined analysis of PCT and presepsin levels led to a significantly higher AUC than the analysis of PCT levels alone for predicting blood culture positivity (0.877 vs. 0.856, P = 0.0344) and gram-negative bacteraemia (0.900 vs. 0.875, P = 0.0216). In a linear regression model, the elevated concentrations of presepsin and PCT were both independently related to Escherichia coli , Klebsiella species, Pseudomonas species, and Streptococcus species infections and Sequential Organ Failure Assessment score. Presepsin levels were also associated with Acinetobacter species and abdominal infection, and PCT levels were positively associated with other Enterobacteriaceae and negatively associated with respiratory infection. Combined analysis of presepsin and PCT levels provided a high sensitivity and specificity in identifying E. coli or Klebsiella species infection. Conclusions: Presepsin and PCT were promising markers for predicting bacteraemia and common pathogens at the time of sepsis onset with a synergistic effect.

Antibiotic use and outcome in patients with negative blood cultures, a new target population for antimicrobial stewardship interventions: A prospective multicentre cohort (NO-BACT).

OBJECTIVES: To evaluate the appropriateness of antimicrobial treatment and the risk factors for mortality in patients with negative blood cultures (BC), in order to evaluate whether this population would be a suitable target for antimicrobial stewardship (AMS) interventions. METHODS: A multicentre prospective cohort study of patients with negative BC in three Spanish hospitals between October 2018 and July 2019 was performed. The main endpoints were the appropriateness of antimicrobial treatment (evaluated by two investigators according to local guidelines) and 30-day mortality. Cox-regression was performed to estimate the association between variables and 30-day mortality. RESULTS: Of 1011 patients in whom BC was obtained, these were negative in 803 (79%) and were included; 30-day mortality was 9% (70 patients); antibiotic treatment was considered inappropriate in 299 (40%) of 747 patients evaluated at day 2, and in 266 (46%) of 573 at day 5-7. The variables independently associated with increased risk of 30-day mortality were higher age (HR 1.05; 95% CI 1.03-1.07), neoplasia (HR 2.73; 95% CI 1.64-4.56), antibiotic treatment in the 48 h prior to BC extraction (HR 2.06; 95% CI 1.23-3.43) and insufficient antibiotic coverage at day 2 after BC obtainment (HR 2.35; 95% CI 1.39-4.00). Urinary, catheter and biliary sources of infection were associated with lower risk (HR 0.40; 95% CI 0.20-0.81). CONCLUSIONS: Antimicrobial treatment is frequently inappropriate among patients with negative BC; insufficient antibiotic coverage at day 2 was associated with mortality. These results suggest that patients with negative BC are a suitable population for AS interventions. SUMMARY: Antimicrobial treatment in patients with negative blood culture was frequently inappropriate, and inappropriate coverage at day 2 was associated with increased risk of death. These data support the consideration of this population as a potential target for antimicrobial stewardship interventions.

[A Case of Mycobacterium abscessus Identified by Suspicious Gram Staining in the Blood Culture of a Patient with Chronic Renal Failure]. / Kronik Böbrek Yetmezlikli Hastanin Kan Kültüründe Süpheli Gram Boyamasi ile Tanimlanan Mycobacterium abscessus Olgusu.

Mycobacterium abscessus (M.abscessus), which is from the group of non-tuberculosis mycobacteria and is widely found in the natural environment, has been reported with increasing frequency as the causative agent of various infections; especially in the lower respiratory tract and in immuncompromised people. In this report, a case of M.abscessus, which developed tubular adenoma, pancytopenia and sepsis on the basis of chronic renal failure (CRF) was diagnosed by suspecting the causative agent in the Gram stain examination prepared from blood culture, was presented. A 49-year-old patient with CRF, who had complaints of weight loss, weakness, and loss of appetite for the last six months, admitted to the emergency department with a 7-8-day history of severe diarrhea and fever. Besides other tests, as the white blood cell count was 1.6 x 103/µl, neutrophil count was 80.6%, hemoglobin was 9.3 g/ dl and the platelet value was 36 x 103/µl in the blood samples, the patient was first taken into internal medicine service and then to the intensive care unit with a preliminary diagnosis of hypotension and sepsis. Meropenem and teicoplanin were started with the preliminary diagnosis of peritonitis in the internal medicine service. In addition to other tests, on the fifth day of antibiotic treatment, two consecutive sets of blood cultures were taken and sent to the microbiology laboratory. A positive signal was obtained from two aerobic blood culture samples at 42 and 45 hours of incubation in the BacT/Alert device. No bacteria were observed in the Gram staining of these samples and Erhlich Ziehl Neelsen (EZN) staining was performed because the structures considered as dye residues were noted as a result of the examination. Acid-fast bacteria were observed in the EZN-stained slide examination, and a panic report was given to the clinician. The patient died shortly after the notification was made in the evening hours. On culture plates inoculated after a positive signal, at the end of two days of aerobic incubation at 37 °C, small smooth S colonies grew on chocolate and sheep blood agar. Growing bacteria were detected as positive by EZN staining and identified as M.abscessus with 99.9% confidence by MALDI-TOF MS. After the bacterium was named as M.abscessus, the isolates were sent to the tuberculosis central laboratory of Süreyyapasa Chest Diseases and Thoracic Surgery Hospital for molecular typing. After DNA extraction from the growing colonies and polymerase chain reaction (PCR), they were typed using the GenoType NTM-DR (Hain Lifescience GmbH, Germany) kit and identified as M.abscessus, consistent with the MALDITOF MS result. After the species level identification, the erm, rrl (clarithromycin, azithromycin), and rrs (kanamycin, amikacin, and gentamicin) genes were investigated in the isolate, and it was determined that the bacteria were resistant to macrolides and sensitive to aminoglycosides. In the clinic, it should be noted that, non-tuberculous mycobacteria may play a role as an agent in immunocompromised people. On the other hand, it should be considered that non-tuberculosis bacteria may be the causative agent, with gram-positive bacilli appearing as stain residues or pale staining in Gram stains made from samples of such patients. As in this case, if the agent is seen as dye residue in blood culture Gram staining samples, it may be life-saving to suspect the agent and to report the result to the clinician accurately and quickly after EZN staining.

Optimizing Blood Culture Collection Volumes.

ABSTRACT: Infection in an immunocompromised person can be a life-threatening emergency. Collection of blood culture specimens is an important method for detecting organisms when infection is suspected. One aspect of proper blood culture collection is obtaining an accurate blood volume in the sample in accordance with the blood culture bottle manufacturer's recommendation. Underfilling the culture bottle can lead to false-negative results, while overfilling it can lead to false-positive results. At our institution, the Department of Laboratory Medicine (DLM) routinely monitors blood culture bottle volumes and notifies the nursing department of underfill/overfill events, which the department then reviews. Over several years, the DLM and the nursing department noted an increase in these events. A clinical nurse specialist and three staff nurses in the oncology/critical care services area partnered with the DLM to determine why. Upon investigation, two key issues-imprecise weighing of bottles and staff misunderstanding of the proper blood culture collection technique-were discovered. In response, the nursing standard of practice and guidance on the DLM webpage were updated and nursing education was performed. As a result, underfill/overfill events decreased by 71% in a little over a year.

The Yield, Safety, and Cost-effectiveness of Decreasing Repeat Blood Cultures Beyond 48 Hours in a Pediatric Hematology-Oncology Unit.

Clear recommendations are needed on when repeat blood cultures (BCxs) in hospitalized children with cancer should be obtained. We reviewed all BCx obtained on the Hematology-Oncology Unit at Riley Hospital for Children, regardless of reason for patient admission or neutropenia status, between January 2015 and February 2021. Patients with positive BCx within 48 hours of initial cultures, history of stem cell transplant, or admitted to the intensive care unit were excluded. Medical records of patients with new positive BCx drawn >48 hours after initial BCx were reviewed. Seven (1.2%) hospitalization episodes grew new pathogens, or commensals treated as pathogens, on cultures beyond 48 hours. All patients with new, true pathogens were hemodynamically unstable or had recurrent fever when the new positive BCx was obtained. Twenty-three (4.0%) hospitalization episodes had contaminant cultures beyond 48 hours, with 74 (5.4%) of 1362 BCx collected beyond 48 hours being contaminated, resulting in an additional cost of $210,519 from increased length of stay. In conclusion, repeat BCx beyond 48 hours in pediatric hematology-oncology patients with negative initial cultures are low yield and costly. Repeat BCx can be safely and cost-effectively ceased after 48 hours of negative cultures in hemodynamically and clinically stable patients.