Predictive scoring models for persistent gram-negative bacteremia that reduce the need for follow-up blood cultures: a retrospective observational cohort study

Abstract Background: Although the risk factors for positive follow-up blood cultures (FUBCs) in gram-negative bacteremia (GNB) have not been investigated extensively, FUBC has been routinely carried out in many acute care hospitals. We attempted to identify the risk factors and develop a predictive scoring model for positive FUBC in GNB cases.Methods: All adults with GNB in a tertiary care hospital were retrospectively identified during a 2-year period, and GNB cases were assigned to eradicable and non-eradicable groups based on whether removal of the source of infection was possible. We performed multivariate logistic analyses to identify risk factors for positive FUBC and built predictive scoring models accordingly. Results: Out of 1,473 GNB cases, FUBCs were carried out in 1,268 cases, and 122 produced positive results. In patient with eradicable source of infection, we assigned points according to the coefficients from the multivariate logistic regression analysis: Extended spectrum beta-lactamase producing microorganism (+1 point), Catheter-related bloodstream infection(+1), unfavorable treatment response (+1), and quick sequential organ failure assessment score of 2 points or more (+1), administration of effective antibiotics (-1), and adequate source control (-2). In non-eradicable source of infection, assigned points were end-stage renal disease on hemodialysis (+1), unfavorable treatment response (+1) and the administration of effective antibiotics (-2). The areas under the curves were 0.861 (95% confidence interval [95CI] 0.806-0.916) and 0.792 (95CI, 0.724-0.861), respectively. When we applied a cut-off of 0, the specificities and negative predictive values (NPVs) in the eradicable and non-eradicable sources of infection groups were 95.6/92.6% and 95.5/95.0%, respectively.Conclusions: FUBC is commonly carried out in GNB cases, but the rate of positive results is less than 10%. In our simple predictive scoring model, zero scores—which were easily achieved following the administration of effective antibiotics and/or adequate source control in both groups—had high NPVs. We expect that the model reported herein will reduce the necessity for FUBCs in GNB cases.

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Predictive scoring models for persistent gram-negative bacteremia that reduce the need for follow-up blood cultures: a retrospective observational cohort study

BMC Infectious Diseases ◽

10.1186/s12879-020-05395-8 ◽

2020 ◽

Vol 20 (1) ◽

Cited By ~ 2

Author(s):

Jongtak Jung ◽

Kyoung-Ho Song ◽

Kang Il. Jun ◽

Chang Kyoung Kang ◽

Nak-Hyun Kim ◽

...

Keyword(s):

Risk Factors ◽

Treatment Response ◽

Blood Cultures ◽

Source Control ◽

Care Hospital ◽

Gram Negative ◽

Scoring Model ◽

Source Of Infection ◽

Gram Negative Bacteremia

Abstract Background Although the risk factors for positive follow-up blood cultures (FUBCs) in gram-negative bacteremia (GNB) have not been investigated extensively, FUBC has been routinely carried out in many acute care hospitals. We attempted to identify the risk factors and develop a predictive scoring model for positive FUBC in GNB cases. Methods All adults with GNB in a tertiary care hospital were retrospectively identified during a 2-year period, and GNB cases were assigned to eradicable and non-eradicable groups based on whether removal of the source of infection was possible. We performed multivariate logistic analyses to identify risk factors for positive FUBC and built predictive scoring models accordingly. Results Out of 1473 GNB cases, FUBCs were carried out in 1268 cases, and the results were positive in 122 cases. In case of eradicable source of infection, we assigned points according to the coefficients from the multivariate logistic regression analysis: Extended spectrum beta-lactamase-producing microorganism (+ 1 point), catheter-related bloodstream infection (+ 1), unfavorable treatment response (+ 1), quick sequential organ failure assessment score of 2 points or more (+ 1), administration of effective antibiotics (− 1), and adequate source control (− 2). In case of non-eradicable source of infection, the assigned points were end-stage renal disease on hemodialysis (+ 1), unfavorable treatment response (+ 1), and the administration of effective antibiotics (− 2). The areas under the curves were 0.861 (95% confidence interval [95CI] 0.806–0.916) and 0.792 (95CI, 0.724–0.861), respectively. When we applied a cut-off of 0, the specificities and negative predictive values (NPVs) in the eradicable and non-eradicable sources of infection groups were 95.6/92.6% and 95.5/95.0%, respectively. Conclusions FUBC is commonly carried out in GNB cases, but the rate of positive results is less than 10%. In our simple predictive scoring model, zero scores—which were easily achieved following the administration of effective antibiotics and/or adequate source control in both groups—had high NPVs. We expect that the model reported herein will reduce the necessity for FUBCs in GNB cases.

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188. Which patients with gram-negative bacteremia need follow-up blood cultures?

Open Forum Infectious Diseases ◽

10.1093/ofid/ofz360.263 ◽

2019 ◽

Vol 6 (Supplement_2) ◽

pp. S114-S114

Author(s):

Jongtak Jung ◽

Song Mi Moon ◽

Eu Suk Kim ◽

Hong Bin Kim ◽

Ji Hwan Bang ◽

...

Keyword(s):

Risk Factors ◽

Treatment Response ◽

Source Control ◽

Care Hospital ◽

Predictive Values ◽

Gram Negative ◽

Negatively Associated ◽

Source Of Infection ◽

Gram Negative Bacteremia

Abstract Background Universal follow-up blood culture (FUBC) in gram-negative bacteremia (GNB) is not recommended, but it has been routinely conducted in many acute-care hospitals. In contrast with Staphylococcus aureus bacteremia, risk factors for positive FUBC in GNB have not been well investigated. Therefore, we tried to identify the risk factors for and develop predictive scores of positive FUBC. Methods All adults (≥18 years-old) with GNB were identified in a tertiary-care hospital during the 2-year period, retrospectively. Death within 2 days of GNB and polymicrobial infection with gram-positive bacteria or fungus were excluded. GNB were classified into eradicable and non-eradicable source of infection groups, according to the possibility of source removal. We performed multivariate analyses for identifying risk factors for positive FUBC and built prediction scores using the coefficients of the multivariate logistic regression models. Results Of total 1,473 GNB, FUBC was drawn in 1,268 (86%) patients and 122 (9.6%) had positive results. In patients with eradicable source of infection, ESBL-producing microorganism, catheter-related bloodstream infection, unfavorable treatment response, and quick sequential organ failure assessment (qSOFA) score (≥2) were associated. On the other hand, administration of effective antibiotics and adequate source control were negatively associated with positive FUBC. In non-eradicable source of infection, end-stage renal disease on hemodialysis, and unfavorable treatment response were related to positive FUBC and administration of effective antibiotics was negatively associated (Table 1). When we built prediction scores according to the coefficients, the areas under the curves were 0.864 (95% confidence interval [CI95] 0.816–0.912) and 0.792 (CI95, 0.721–0.861), respectively. When we applied a cutoff of 0, specificities/negative predictive values in eradicable and non-eradicable source of infection groups were 84.7%/95.6% and 95.5%/95.0%, respectively (Table 2). Conclusion Our prediction scores based on adequate source control and use of effective antibiotics showed high specificities and negative predictive values. Therefore, we could expect these score systems to contribute to reducing unnecessary FUBC in GNB. Disclosures All authors: No reported disclosures.

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The Changing Landscape of Uncomplicated Gram-Negative Bacteremia: A Narrative Review to Guide Inpatient Management

Journal of Hospital Medicine ◽

10.12788/jhm.3414 ◽

2020 ◽

Vol 15 (12) ◽

pp. 746-753 ◽

Cited By ~ 1

Author(s):

Jeannie D Chan ◽

Chloe Bryson-Cahn ◽

Zahra Kassamali-Escobar ◽

John B Lynch ◽

Anneliese M Schleyer

Keyword(s):

Cost Effective ◽

Hospital Length ◽

Antimicrobial Treatment ◽

Blood Cultures ◽

Hospital Length Of Stay ◽

Source Control ◽

Gram Negative ◽

Oral Agents ◽

Gram Negative Bacteremia

Gram-negative bacteremia secondary to focal infection such as skin and soft-tissue infection, pneumonia, pyelonephritis, or urinary tract infection is commonly encountered in hospital care. Current practice guidelines lack sufficient detail to inform evidence-based practices. Specifically, antimicrobial duration, criteria to transition from intravenous to oral step-down therapy, choice of oral antimicrobials, and reassessment of follow-up blood cultures are not addressed. The presence of bacteremia is often used as a justification for a prolonged course of antimicrobial therapy regardless of infection source or clinical response. Antimicrobials are lifesaving but not benign. Prolonged antimicrobial exposure is associated with adverse effects, increased rates of Clostridioides difficile infection, antimicrobial resistance, and longer hospital length of stay. Emerging evidence supports shorter overall duration of antimicrobial treatment and earlier transition to oral agents among patients with uncomplicated Enterobacteriaceae bacteremia who have achieved adequate source control and demonstrated clinical stability and improvement. After appropriate initial treatment with an intravenous antimicrobial, transition to highly bioavailable oral agents should be considered for total treatment duration of 7 days. Routine follow-up blood cultures are not cost-effective and may result in unnecessary healthcare resource utilization and inappropriate use of antimicrobials. Clinicians should incorporate these principles into the management of gram-negative bacteremia in the hospital.

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Does This Patient Need Blood Cultures? A Scoping Review of Indications for Blood Cultures in Adult Nonneutropenic Inpatients

Clinical Infectious Diseases ◽

10.1093/cid/ciaa039 ◽

2020 ◽

Vol 71 (5) ◽

pp. 1339-1347 ◽

Cited By ~ 4

Author(s):

Valeria Fabre ◽

Sima L Sharara ◽

Alejandra B Salinas ◽

Karen C Carroll ◽

Sanjay Desai ◽

...

Keyword(s):

Risk Factors ◽

Scoping Review ◽

Primary Source ◽

Blood Cultures ◽

Source Control ◽

High Likelihood ◽

Source Of Infection ◽

Patients At Risk ◽

High Pretest Probability

Abstract Guidance regarding indications for initial or follow-up blood cultures is limited. We conducted a scoping review of articles published between January 2004 and June 2019 that reported the yield of blood cultures and/or their impact in the clinical management of fever and common infectious syndromes in nonneutropenic adult inpatients. A total of 2893 articles were screened; 50 were included. Based on the reported incidence of bacteremia, syndromes were categorized into low, moderate, and high pretest probability of bacteremia. Routine blood cultures are recommended in syndromes with a high likelihood of bacteremia (eg, endovascular infections) and those with moderate likelihood when cultures from the primary source of infection are unavailable or when prompt initiation of antibiotics is needed prior to obtaining primary source cultures. In syndromes where blood cultures are low-yield, blood cultures can be considered for patients at risk of adverse events if a bacteremia is missed (eg, patient with pacemaker and severe purulent cellulitis). If a patient has adequate source control and risk factors or concern for endovascular infection are not present, most streptococci or Enterobacterales bacteremias do not require routine follow-up blood cultures.

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Are Follow-Up Blood Cultures Useful in the Antimicrobial Management of Gram Negative Bacteremia? A Reappraisal of Their Role Based on Current Knowledge

Antibiotics ◽

10.3390/antibiotics9120895 ◽

2020 ◽

Vol 9 (12) ◽

pp. 895

Author(s):

Francesco Cogliati Dezza ◽

Ambrogio Curtolo ◽

Lorenzo Volpicelli ◽

Giancarlo Ceccarelli ◽

Alessandra Oliva ◽

...

Keyword(s):

Critically Ill ◽

Critically Ill Patients ◽

Current Knowledge ◽

Bloodstream Infections ◽

Blood Cultures ◽

Source Control ◽

Candida Spp ◽

Gram Negative ◽

Gram Negative Bacteremia

Bloodstream infections still constitute an outstanding cause of in-hospital morbidity and mortality, especially among critically ill patients. Follow up blood cultures (FUBCs) are widely recommended for proper management of Staphylococcus aureus and Candida spp. infections. On the other hand, their role is still a matter of controversy as far as Gram negative bacteremias are concerned. We revised, analyzed, and commented on the literature addressing this issue, to define the clinical settings in which the application of FUBCs could better reveal its value. The results of this review show that critically ill patients, endovascular and/or non-eradicable source of infection, isolation of a multi-drug resistant pathogen, end-stage renal disease, and immunodeficiencies are some factors that may predispose patients to persistent Gram negative bacteremia. An analysis of the different burdens that each of these factors have in this clinical setting allowed us to suggest which patients’ FUBCs have the potential to modify treatment choices, prompt an early source control, and finally, improve clinical outcome.

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Risk Factors for Positive Follow-Up Blood Cultures in Gram-Negative Bacilli Bacteremia: Implications for Selecting Who Needs Follow-Up Blood Cultures

Open Forum Infectious Diseases ◽

10.1093/ofid/ofaa110 ◽

2020 ◽

Vol 7 (4) ◽

Cited By ~ 2

Author(s):

Hayato Mitaka ◽

Tessa Gomez ◽

Young Im Lee ◽

David C Perlman

Keyword(s):

Risk Factors ◽

Cohort Study ◽

Blood Culture ◽

Retrospective Cohort Study ◽

Retrospective Cohort ◽

Multivariate Logistic Regression Analysis ◽

Blood Cultures ◽

Gram Negative ◽

Intravascular Devices

Abstract Background The value of follow-up blood cultures (FUBCs) to document clearance of bacteremia due to Gram-negative bacilli (GNB) has not been well established. Although previous studies suggested that the yield of FUBCs for GNB bacteremia is low, it remains to be elucidated for whom FUBC may be beneficial and for whom it is unnecessary. Methods A retrospective cohort study was performed at 4 acute care hospitals to identify risk factors for positive FUBCs with GNB bacteremia and to better guide clinicians’ decisions as to which patients may or may not benefit from FUBCs. Participants included adult patients with GNB bacteremia who had FUBCs and were admitted between January 2017 and December 2018. The primary outcomes were the factors associated with positive FUBCs and the yield of FUBCs with and without the factors. Results Of 306 patients with GNB bacteremia who had FUBCs, 9.2% (95% confidence interval, 6.2%–13.0%) had the same GNB in FUBCs. In the multivariate logistic regression analysis, end-stage renal disease on hemodialysis, intravascular device, and bacteremia due to extended-spectrum β-lactamase or carbapenemase-producing organism were identified as independent predictors of positive FUBCs with GNB bacteremia. Approximately 7 FUBCs and 30 FUBCs were needed for patients with ≥1 or no risk factors, respectively, to yield 1 positive result. SummaryThis multi-site retrospective cohort study found that among patients with gram-negative bacilli (GNB) bacteremia, having ESRD on hemodialysis, intravascular devices, or bacteremia due to multi-drug resistant GNB were each independently associated with having a positive follow-up blood culture. Conclusions Follow-up blood culture may not be necessary for all patients with GNB bacteremia and has the highest yield in patients with 1 or more risk factors.

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Follow-up Blood Cultures: A 2.0 Diagnostic Tool in Patients With Gram-Negative Bacteremia and Septic Thrombophlebitis

Clinical Infectious Diseases ◽

10.1093/cid/cix949 ◽

2017 ◽

Vol 66 (7) ◽

pp. 1154-1155 ◽

Cited By ~ 7

Author(s):

Giancarlo Ceccarelli ◽

Simone Giuliano ◽

Marco Falcone ◽

Mario Venditti

Keyword(s):

Diagnostic Tool ◽

Blood Cultures ◽

Septic Thrombophlebitis ◽

Gram Negative ◽

Gram Negative Bacteremia

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290. Impact of follow up blood cultures on outcomes of patients with gram-negative bloodstream infections

Open Forum Infectious Diseases ◽

10.1093/ofid/ofaa439.333 ◽

2020 ◽

Vol 7 (Supplement_1) ◽

pp. S145-S145

Author(s):

Rajiv G Amipara ◽

Hana R Winders ◽

Julie Ann Justo ◽

P B Bookstaver ◽

Joseph Kohn ◽

...

Keyword(s):

South Carolina ◽

Blood Culture ◽

Proportional Hazards ◽

Bloodstream Infections ◽

Cox Proportional Hazards ◽

Blood Cultures ◽

Gram Negative ◽

Source Of Infection

Abstract Background Importance of follow up blood cultures (FUBC) for Staphylococcus aureus bloodstream infections (BSI) is well known, but the role of FUBC in gram-negative BSI remains controversial. This retrospective cohort study examined the association between obtaining FUBC and mortality in patients with gram-negative BSI. Methods Adults with first episodes of community-onset monomicrobial BSI due to gram-negative bacilli hospitalized at Prisma Health-Midlands hospitals in Columbia, South Carolina, USA from January 1, 2010 to June 30, 2015 were identified. Patients who died or were discharged from hospital within 72 hours of collection of index blood culture were excluded to minimize impact of survival and selection biases on results, respectively. FUBC were defined as repeat blood cultures obtained between 24 and 96 hours from initial positive blood culture. Cox proportional hazards regression model was used to examine association between obtaining FUBC and 28-day all-cause mortality. Results Among 766 patients with gram-negative BSI, 219 (28.6%) had FUBC obtained and 15 of 219 (6.8%) FUBC were persistently positive. Overall, median age was 67 years, 438 (57%) were women, 457 (60%) had urinary source of infection, and 426 (56%) had BSI due to Escherichia coli. Mortality was significantly lower in patients who had FUBC obtained than in those who did not have FUBC (6.3% vs. 11.7%, log-rank p=0.03). Obtaining FUBC was independently associated with reduced mortality (hazards ratio [HR] 0.49, 95%CI: 0.25–0.90) after adjustments for age (HR 1.35 per decade, 95% CI: 1.13–1.61), cancer (HR 5.90, 95% CI: 3.53–9.84), Pitt bacteremia score (HR 1.38 per point, 95% CI: 1.26–1.50), and inappropriate empirical antimicrobial therapy (HR 2.37, 95% CI: 1.17–4.39). Conclusion Obtaining FUBC was associated with improved survival in hospitalized patients with gram-negative BSI. These observations are consistent with the results of recent publications from Italy and North Carolina supporting utilization of FUBC in the management of gram-negative BSI. Disclosures Julie Ann Justo, PharmD, MS, BCPS-AQ ID, bioMerieux (Speaker’s Bureau)TRC Healthcare (Speaker’s Bureau)

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