Cellular host response sepsis test for risk stratification of patients in the emergency department: A pooled analysis

OBJECTIVES

Sepsis is one of the most common, costly, and misdiagnosed conditions in U.S. emergency departments (EDs). ED providers often treat on nonspecific signs, subjective suspicion, or presumption of infection, resulting in over- and undertreatment. An increased understanding of host response has opened a new direction for sepsis diagnostics. The IntelliSep test is a U.S. Food and Drug Administration-cleared cellular host response diagnostic that could help distinguish sepsis in ED settings. Our objective was to evaluate the potential of the cellular host response test to expedite appropriate care for patients who present with signs of infection.

METHODS

We performed a pooled analysis of five adult (≥18 years) cohorts enrolled at seven geographically diverse U.S. sites in separate studies. Structured blinded adjudication was used to classify presence or absence of sepsis, and only patients with high confidence in the adjudicated label were included (n = 1002), defined as patients for whom there was consensus in the determination of sepsis per the Sepsis-3 and severe sepsis per the Sepsis-2 definitions between both the independent adjudication panel and the site-level physician.

RESULTS

Among patients with signs or suspicion of infection, the test achieved similar or better performance compared to other indicators in identifying patients at high risk for sepsis (specificity > 83%) and significantly superior performance in identifying those at low risk (sensitivity > 92%; 0% sepsis-associated mortality). The test also stratified severity of illness, as shown by 30-day in-hospital mortality (p < 0.001), hospital length of stay (p < 0.01), and use of hospital resources (p < 0.001).

CONCLUSIONS

Our data suggest that the cellular host response test provides clinically actionable results for patients at both high and low risk for sepsis and provides a rapid, objective means for risk stratification of patients with signs of infection. If integrated into standard of care, the test may help improve outcomes and reduce unnecessary antibiotic use.

Validation of a Novel, Rapid Sepsis Diagnostic for Emergency Department Use

OBJECTIVES

To assess the in vitro IntelliSep test, a microfluidic assay that quantifies the state of immune activation by evaluating the biophysical properties of leukocytes, as a rapid diagnostic for sepsis.

DESIGN

Prospective cohort study.

SETTING

Five emergency departments (EDs) in Louisiana, Missouri, North Carolina, and Washington.

PATIENTS

Adult patients presenting to the ED with signs (two of four Systemic Inflammatory Response Syndrome criteria, where one must be temperature or WBC count) or suspicion (provider-ordered culture) of infection.

INTERVENTIONS

All patients underwent testing with the IntelliSep using ethylene diamine tetraacetic acid-anticoagulated whole blood followed by retrospective adjudication for sepsis by sepsis-3 criteria by a blinded panel of physicians.

MEASUREMENTS AND MAIN RESULTS

Of 599 patients enrolled, 572 patients were included in the final analysis. The result of the IntelliSep test is reported as the IntelliSep Index (ISI), ranging from 0.1 to 10.0, divided into three interpretation bands for the risk of sepsis: band 1 (low) to band 3 (high). The median turnaround time for ISI results was 7.2 minutes. The ISI resulted band 1 in 252 (44.1%), band 2 in 160 (28.0%), and band 3 in 160 (28.0%). Sepsis occurred in 26.6% (152 of 572 patients). Sepsis prevalence was 11.1% (95% CI, 7.5-15.7%) in band 1, 28.1% (95% CI, 21.3-35.8%) in band 2, and 49.4% (95% CI, 41.4-57.4%) in band 3. The Positive Percent Agreement of band 1 was 81.6% and the Negative Percent Agreement of band 3 was 80.7%, with an area under the receiver operating characteristic curve of 0.74. Compared with band 1, band 3 correlated with adverse clinical outcomes, including mortality, and resource utilization.

CONCLUSIONS

Increasing ISI interpretation band is associated with increasing probability of sepsis in patients presenting to the ED with suspected infection.

Costs and Consequences of a Novel Emergency Department Sepsis Diagnostic Test: The IntelliSep Index

Sepsis causes 270,000 deaths and costs $38 billion annually in the United States. Most cases of sepsis present in the emergency department (ED), where rapid diagnosis remains challenging. The IntelliSep Index (ISI) is a novel diagnostic test that analyzes characteristics of WBC structure and provides a reliable early signal for sepsis. This study performs a cost-consequence analysis of the ISI relative to procalcitonin for early sepsis diagnosis in the ED.

PERSPECTIVE

U.S. healthcare system.

SETTING

Community hospital ED.

METHODS

A decision tree analysis was performed comparing ISI with procalcitonin. Model parameters included prevalence of sepsis, sensitivity and specificity of diagnostic tests (both ISI and procalcitonin), costs of hospitalization, and mortality rate stratified by diagnostic test result. Mortality and prevalence of sepsis were estimated from best available literature. Costs were estimated based on an analysis of a large, national discharge dataset, and adjusted to 2018 U.S. dollars. Outcomes included expected costs and survival.

RESULTS

Assuming a confirmed sepsis prevalence of 16.9% (adjudicated to Sepsis-3), the ISI strategy had an expected cost per patient of $3,849 and expected survival rate of 95.08%, whereas the procalcitonin strategy had an expected cost of $4,656 per patient and an expected survival of 94.98%. ISI was both less costly and more effective than procalcitonin, primarily because of fewer false-negative results. These results were robust in sensitivity analyses.

CONCLUSIONS

ISI was both less costly and more effective in preventing mortality than procalcitonin, primarily because of fewer false-negative results. The ISI may provide health systems with a higher-value diagnostic test in ED sepsis evaluation. Additional work is needed to validate these results in clinical practice.

Rapid identification of sepsis in the emergency department

Objectives

Recent research has helped define the complex pathways in sepsis, affording new opportunities for advancing diagnostics tests. Given significant advances in the field, a group of academic investigators from emergency medicine, intensive care, pathology, and pharmacology assembled to develop consensus around key gaps and potential future use for emerging rapid host response diagnostics assays in the emergency department (ED) setting.

Methods

A modified Delphi study was conducted that included 26 panelists (expert consensus panel) from multiple specialties. A smaller steering committee first defined a list of Delphi statements related to the need for and future potential use of a hypothetical sepsis diagnostic test in the ED. Likert scoring was used to assess panelists agreement or disagreement with statements. Two successive rounds of surveys were conducted and consensus for statements was operationally defined as achieving agreement or disagreement of 75% or greater.

Results

Significant gaps were identified related to current tools for assessing risk of sepsis in the ED. Strong consensus indicated the need for a test providing an indication of the severity of dysregulated host immune response, which would be helpful even if it did not identify the specific pathogen. Although there was a relatively high degree of uncertainty regarding which patients would most benefit from the test, the panel agreed that an ideal host response sepsis test should aim to be integrated into ED triage and thus should produce results in less than 30 minutes. The panel also agreed that such a test would be most valuable for improving sepsis outcomes and reducing rates of unnecessary antibiotic use.

Conclusion

The expert consensus panel expressed strong consensus regarding gaps in sepsis diagnostics in the ED and the potential for new rapid host response tests to help fill these gaps. These finding provide a baseline framework for assessing key attributes of evolving host response diagnostic tests for sepsis in the ED.

Neutralizing COVID-19 Convalescent Plasma in Adults Hospitalized With COVID-19: A Blinded, Randomized, Placebo-Controlled Trial

BACKGROUND

Convalescent plasma has been one of the most common treatments for COVID-19, but most clinical trial data to date have not supported its efficacy.

RESEARCH QUESTION

Is rigorously selected COVID-19 convalescent plasma with neutralizing anti-SARS-CoV-2 antibodies an efficacious treatment for adults hospitalized with COVID-19?

STUDY DESIGN AND METHODS

This was a multicenter, blinded, placebo-controlled randomized clinical trial among adults hospitalized with SARS-CoV-2 infection and acute respiratory symptoms for < 14 days. Enrolled patients were randomly assigned to receive one unit of COVID-19 convalescent plasma (n = 487) or placebo (n = 473). The primary outcome was clinical status (disease severity) 14 days following study infusion measured with a seven-category ordinal scale ranging from discharged from the hospital with resumption of normal activities (lowest score) to death (highest score). The primary outcome was analyzed with a multivariable ordinal regression model, with an adjusted odds ratio (aOR) < 1.0 indicating more favorable outcomes with convalescent plasma than with placebo. In secondary analyses, trial participants were stratified according to the presence of endogenous anti-SARS-CoV-2 antibodies ("serostatus") at randomization. The trial included 13 secondary efficacy outcomes, including 28-day mortality.

RESULTS

Among 974 randomized patients, 960 were included in the primary analysis. Clinical status on the ordinal outcome scale at 14 days did not differ between the convalescent plasma and placebo groups in the overall population (aOR, 1.04; one-seventh support interval [1/7 SI], 0.82-1.33), in patients without endogenous antibodies (aOR, 1.15; 1/7 SI, 0.74-1.80), or in patients with endogenous antibodies (aOR, 0.96; 1/7 SI, 0.72-1.30). None of the 13 secondary efficacy outcomes were different between groups. At 28 days, 89 of 482 (18.5%) patients in the convalescent plasma group and 80 of 465 (17.2%) patients in the placebo group had died (aOR, 1.04; 1/7 SI, 0.69-1.58).

INTERPRETATION

Among adults hospitalized with COVID-19, including those seronegative for anti-SARS-CoV-2 antibodies, treatment with convalescent plasma did not improve clinical outcomes.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov; No.: NCT04362176; URL: www.

CLINICALTRIALS

gov.

Retrospective Identification of Infection in the Emergency Department: A Significant Challenge in Sepsis Clinical Trials

BACKGROUND

This study examined three methods for retrospectively identifying infection in emergency department (ED) patients: modified objective definitions of infection (MODI) from the CDC/NHSN, physician adjudication determination of infection, and ED treating physician behavior.

METHOD

This study used a subset of data from a prospective sepsis trial. We used Fleiss's Kappa to compare agreement between two physicians retrospectively adjudicating infection based on the patient's medical record, modified infection definition from the CDC/NHSN, and ED treating physician behavior.

RESULTS

Overall, there was similar agreement between physician adjudication of infection and MODI criteria (Kappa=0.59) compared to having two physicians independently identify infection through retrospective chart review (Kappa=0.58). ED treating physician behavior was a poorer proxy for infection when compared to the MODI criteria (0.41) and physician adjudication (Kappa = 0.50).

CONCLUSION

Retrospective identification of infection poses a significant challenge in sepsis clinical trials. Using modified definitions of infection provides a standardized, less time consuming, and equally effective means of identifying infection compared to having multiple physicians adjudicate a patient's chart.

Dexmedetomidine or Propofol for Sedation in Mechanically Ventilated Adults with Sepsis

BACKGROUND

Guidelines currently recommend targeting light sedation with dexmedetomidine or propofol for adults receiving mechanical ventilation. Differences exist between these sedatives in arousability, immunity, and inflammation. Whether they affect outcomes differentially in mechanically ventilated adults with sepsis undergoing light sedation is unknown.

METHODS

In a multicenter, double-blind trial, we randomly assigned mechanically ventilated adults with sepsis to receive dexmedetomidine (0.2 to 1.5 μg per kilogram of body weight per hour) or propofol (5 to 50 μg per kilogram per minute), with doses adjusted by bedside nurses to achieve target sedation goals set by clinicians according to the Richmond Agitation-Sedation Scale (RASS, on which scores range from -5 [unresponsive] to +4 [combative]). The primary end point was days alive without delirium or coma during the 14-day intervention period. Secondary end points were ventilator-free days at 28 days, death at 90 days, and age-adjusted total score on the Telephone Interview for Cognitive Status questionnaire (TICS-T; scores range from 0 to 100, with a mean of 50±10 and lower scores indicating worse cognition) at 6 months.

RESULTS

Of 432 patients who underwent randomization, 422 were assigned to receive a trial drug and were included in the analyses - 214 patients received dexmedetomidine at a median dose of 0.27 μg per kilogram per hour, and 208 received propofol at a median dose of 10.21 μg per kilogram per minute. The median duration of receipt of the trial drugs was 3.0 days (interquartile range, 2.0 to 6.0), and the median RASS score was -2.0 (interquartile range, -3.0 to -1.0). We found no difference between dexmedetomidine and propofol in the number of days alive without delirium or coma (adjusted median, 10.7 vs. 10.8 days; odds ratio, 0.96; 95% confidence interval [CI], 0.74 to 1.26), ventilator-free days (adjusted median, 23.7 vs. 24.0 days; odds ratio, 0.98; 95% CI, 0.63 to 1.51), death at 90 days (38% vs. 39%; hazard ratio, 1.06; 95% CI, 0.74 to 1.52), or TICS-T score at 6 months (adjusted median score, 40.9 vs. 41.4; odds ratio, 0.94; 95% CI, 0.66 to 1.33). Safety end points were similar in the two groups.

CONCLUSIONS

Among mechanically ventilated adults with sepsis who were being treated with recommended light-sedation approaches, outcomes in patients who received dexmedetomidine did not differ from outcomes in those who received propofol. (Funded by the National Institutes of Health; ClinicalTrials.gov number, NCT01739933.).

Passive Immunity Trial for Our Nation (PassITON): study protocol for a randomized placebo-control clinical trial evaluating COVID-19 convalescent plasma in hospitalized adults

BACKGROUND

Convalescent plasma is being used widely as a treatment for coronavirus disease 2019 (COVID-19). However, the clinical efficacy of COVID-19 convalescent plasma is unclear.

METHODS

The Passive Immunity Trial for Our Nation (PassITON) is a multicenter, placebo-controlled, blinded, randomized clinical trial being conducted in the USA to provide high-quality evidence on the efficacy of COVID-19 convalescent plasma as a treatment for adults hospitalized with symptomatic disease. Adults hospitalized with COVID-19 with respiratory symptoms for less than 14 days are eligible. Enrolled patients are randomized in a 1:1 ratio to 1 unit (200-399 mL) of COVID-19 convalescent plasma that has demonstrated neutralizing function using a SARS-CoV-2 chimeric virus neutralization assay. Study treatments are administered in a blinded fashion and patients are followed for 28 days. The primary outcome is clinical status 14 days after study treatment as measured on a 7-category ordinal scale assessing mortality, respiratory support, and return to normal activities of daily living. Key secondary outcomes include mortality and oxygen-free days. The trial is projected to enroll 1000 patients and is designed to detect an odds ratio ≤ 0.73 for the primary outcome.

DISCUSSION

This trial will provide the most robust data available to date on the efficacy of COVID-19 convalescent plasma for the treatment of adults hospitalized with acute moderate to severe COVID-19. These data will be useful to guide the treatment of COVID-19 patients in the current pandemic and for informing decisions about whether developing a standardized infrastructure for collecting and disseminating convalescent plasma to prepare for future viral pandemics is indicated.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04362176 . Registered on 24 April 2020.

Passive Immunity Trial for Our Nation (PassITON): study protocol for a randomized placebo-control clinical trial evaluating COVID-19 convalescent plasma in hospitalized adults

Background: Convalescent plasma is being used widely as a treatment for coronavirus disease 2019 (COVID-19). However, the clinical efficacy of COVID-19 convalescent plasma is unclear. Methods: The Pass ive I mmunity T rial for O ur N ation (PassITON), is a multicenter, placebo-controlled, blinded, randomized clinical trial being conducted in the United States to provide high-quality evidence on the efficacy of COVID-19 convalescent plasma as a treatment for adults hospitalized with symptomatic disease. Adults hospitalized with COVID-19 with respiratory symptoms for less than 14 days are eligible. Enrolled patients are randomized in a 1:1 ratio to 1 unit (200-399 mL) of COVID-19 convalescent plasma that has demonstrated neutralizing function using a SARS-CoV-2 chimeric virus neutralization assay. Study treatments are administered in a blinded fashion and patients are followed for 28 days. The primary outcome is clinical status 14 days after study treatment as measured on a 7-category ordinal scale assessing mortality, respiratory support, and return to normal activities of daily living. Key secondary outcomes include mortality and oxygen-free days. The trial is projected to enroll 1000 patients and is designed to detect an odds ratio ≤ 0.73 for the primary outcome. Discussion: This trial will provide the most robust data available to date on the efficacy of COVID-19 convalescent plasma for the treatment of adults hospitalized with acute moderate to severe COVID-19. These data will be useful to guide the treatment of COVID-19 patients in the current pandemic and for informing decisions about whether developing a standardized infrastructure for collecting and disseminating convalescent plasma to prepare for future viral pandemics is indicated. Trial Registration: ClinicalTrials.gov: NCT04362176. Date of trial registration: April 24, 2020, https://clinicaltrials.gov/ct2/show/NCT04362176.

Prevalence and risk factors for delirium in critically ill patients with COVID-19 (COVID-D): a multicentre cohort study

Background

To date, 750 000 patients with COVID-19 worldwide have required mechanical ventilation and thus are at high risk of acute brain dysfunction (coma and delirium). We aimed to investigate the prevalence of delirium and coma, and risk factors for delirium in critically ill patients with COVID-19, to aid the development of strategies to mitigate delirium and associated sequelae.

Methods

This multicentre cohort study included 69 adult intensive care units (ICUs), across 14 countries. We included all patients (aged ≥18 years) admitted to participating ICUs with severe acute respiratory syndrome coronavirus 2 infection before April 28, 2020. Patients who were moribund or had life-support measures withdrawn within 24 h of ICU admission, prisoners, patients with pre-existing mental illness, neurodegenerative disorders, congenital or acquired brain damage, hepatic coma, drug overdose, suicide attempt, or those who were blind or deaf were excluded. We collected de-identified data from electronic health records on patient demographics, delirium and coma assessments, and management strategies for a 21-day period. Additional data on ventilator support, ICU length of stay, and vital status was collected for a 28-day period. The primary outcome was to determine the prevalence of delirium and coma and to investigate any associated risk factors associated with development of delirium the next day. We also investigated predictors of number of days alive without delirium or coma. These outcomes were investigated using multivariable regression.

Findings

Between Jan 20 and April 28, 2020, 4530 patients with COVID-19 were admitted to 69 ICUs, of whom 2088 patients were included in the study cohort. The median age of patients was 64 years (IQR 54 to 71) with a median Simplified Acute Physiology Score (SAPS) II of 40·0 (30·0 to 53·0). 1397 (66·9%) of 2088 patients were invasively mechanically ventilated on the day of ICU admission and 1827 (87·5%) were invasively mechanical ventilated at some point during hospitalisation. Infusion with sedatives while on mechanical ventilation was common: 1337 (64·0%) of 2088 patients were given benzodiazepines for a median of 7·0 days (4·0 to 12·0) and 1481 (70·9%) were given propofol for a median of 7·0 days (4·0 to 11·0). Median Richmond Agitation–Sedation Scale score while on invasive mechanical ventilation was –4 (–5 to –3). 1704 (81·6%) of 2088 patients were comatose for a median of 10·0 days (6·0 to 15·0) and 1147 (54·9%) were delirious for a median of 3·0 days (2·0 to 6·0). Mechanical ventilation, use of restraints, and benzodiazepine, opioid, and vasopressor infusions, and antipsychotics were each associated with a higher risk of delirium the next day (all p≤0·04), whereas family visitation (in person or virtual) was associated with a lower risk of delirium (p<0·0001). During the 21-day study period, patients were alive without delirium or coma for a median of 5·0 days (0·0 to 14·0). At baseline, older age, higher SAPS II scores, male sex, smoking or alcohol abuse, use of vasopressors on day 1, and invasive mechanical ventilation on day 1 were independently associated with fewer days alive and free of delirium and coma (all p<0·01). 601 (28·8%) of 2088 patients died within 28 days of admission, with most of those deaths occurring in the ICU.

Interpretation

Acute brain dysfunction was highly prevalent and prolonged in critically ill patients with COVID-19. Benzodiazepine use and lack of family visitation were identified as modifiable risk factors for delirium, and thus these data present an opportunity to reduce acute brain dysfunction in patients with COVID-19.

Funding

None.

Translations

For the French and Spanish translations of the abstract see Supplementary Materials section.

Variability in Management of Patients With SJS/TEN: A Survey of Burn Unit Directors

Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are rare, type IV hypersensitivity reactions of the skin and mucosa. These reactions (SJS/TEN) are frequently managed in burn units; however, no standardized guidelines exist for the treatment and management of SJS/TEN. To gain insight into current SJS/TEN management practices, a survey on admission, diagnosis, and management, was conducted across accredited burn units in the United States. A 28-item question survey on SJS/TEN management, diagnosis, and treatment practices was distributed among medical directors and co-directors of American Burn Association-verified burn centers. Responses were collected over a 6-week period. In total, 31 (48% response rate) burn unit medical directors/co-directors participated in the survey. The majority of responders indicate that acceptance to their burn unit is based on clinical suspicion of SJS/TEN (74%), and biopsy or dermatological evaluation is not required (67 and 87%, respectively). More than half (61%) of the burn units have their own SJS/TEN protocol in place. No consensus was observed on different treatment aspects, such as infection control, systemic treatment, and wound care. Most directors reported their burn units to consult ophthalmology (77%) and dermatology (54%) for the management of patients with SJS/TEN. Large variability in procedures of admission, treatment, and management of SJS/TEN was identified across burn centers. This study demonstrates the urgent need for SJS/TEN standardized guidelines in the United States.

Ceftaroline-Associated Neutropenia: Case Series and Literature Review of Incidence, Risk Factors, and Outcomes

Ceftaroline is increasingly prescribed for "off-label" indications involving longer durations and higher doses. There have been postmarketing case reports of neutropenia among patients who have received extended durations of ceftaroline, but limited published data currently exist on its incidence and risk factors. We review a total of 37 published cases of ceftaroline-associated neutropenia including cases (n = 4) identified in our health care system. The median time from ceftaroline initiation to development of neutropenia (range) was 25 (8-125) days, with a median duration of neutropenia (range) of 4 (1-16) days. Agranulocytosis (absolute neutrophil count [ANC] nadir < 100 cells/mm³) developed in 49% of cases (n = 18), and there was an ANC nadir of 0 in 27% (n = 10). The overall incidence of neutropenia among cases receiving ceftaroline for ≥7-14 days (range) was 12% (7%-18% per individual study), higher than for comparator antibiotics in the literature. Risk factors for ceftaroline-associated neutropenia varied among studies and remain poorly defined.

Critical Illness in Patients With Asplenia

The critically ill, asplenic patient presents a variety of management challenges. Historically, the focus of the care of the asplenic population has been the prevention and management of infection, including the often-fatal overwhelming postsplenectomy infection with encapsulated organisms such as Streptococcus pneumoniae. Recently, however, there has been increasing recognition of the spleen's function in areas outside of immunity because the asplenic state has been identified as a risk factor for such vascular complications as thrombosis and pulmonary hypertension resulting from dysregulated inflammation and coagulation. Because of the relatively small size of this population and the relative infrequency with which critical illness occurs in it, there are few controlled trials that can serve as a basis for therapeutic maneuvers; thus, optimal management requires an astute clinician with an understanding of the pathogenetic mechanisms underlying the reported consequences of splenectomy. The purpose of this review is to explore the pathophysiology of the asplenic state-impairment in adaptive immunity, loss of blood filtration, endothelial dysfunction, and dysregulated coagulation-and how it leads to infection, thrombosis, and pulmonary hypertension as well as to discuss the implications of these conditions on the management of the critically ill, splenectomized patient.

Neutropenia Associated with Long-Term Ceftaroline Use

Ceftaroline is a fifth-generation cephalosporin with potent antimicrobial activity against Gram-positive and Gram-negative pathogens. Neutropenia is a rare serious adverse event for the class of cephalosporins; however, we observed several cases of severe neutropenia in our outpatient infectious disease practice believed to be associated with ceftaroline use. The aim of this study was to determine the incidence of neutropenia among patients receiving ceftaroline therapy for more than 7 days. We conducted a retrospective cohort analysis of patients admitted to an 800-bed regional medical center between June 2012 and December 2014 who received ceftaroline for more than 7 days to assess the incidence of developing clinically significant neutropenia. Demographic and patient care data points as well as underlying admitting and chronic diagnoses were retrospectively collected from the medical record. Clinically significant neutropenia was defined as an absolute neutrophil count (ANC) less than 1,500 cells/mm(3). Analysis was performed to determine the incidence, severity, and outcome of neutropenia following ceftaroline administration. A total of 39 patients were included in the cohort. The median duration of therapy was 27 days. Seven patients (18%) developed neutropenia while on ceftaroline therapy. Four (10%) of the neutropenic patients had an ANC of <500 cells/mm(3). The median first neutropenic day was day 17, with the median ANC nadir of 432 cells/mm(3) on day 24. We determined that extended ceftaroline infusion is associated with the development of neutropenia. We recommend obtaining a complete blood count (CBC) with differential at the onset of therapy and weekly thereafter. Should the ANC fall below 2,500 cells/mm(3), then twice-weekly CBCs should be monitored for the duration of ceftaroline therapy, and therapy should be discontinued if the ANC falls to 1,500 cells/mm(3) or less.

Treatment outcomes in patients with third-generation cephalosporin-resistant Enterobacter bacteremia

BACKGROUND

Infections with resistant Enterobacter spp. are increasingly described, yet data on outcomes associated with these infections are limited.

METHODS

A retrospective cohort study was conducted to investigate outcomes of hospitalized patients with third-generation cephalosporin-resistant (CR) Enterobacter bacteremia. Cephalosporin resistance was detected using cefotaxime and cefpodoxime. Patients with Enterobacter spp. bacteremia from January 2006 through February 2008 defined the population. We defined cases as those with CR isolates; controls were patients with bacteremia due to non-CR isolates. Treatment failure was defined as persistence of the presenting signs of infection 72 h after initial culture collection.

RESULTS

Of the 95 Enterobacter cases identified, 31 (33%) were CR. CR cases were significantly associated with treatment failure (odds ratio (OR) 2.81, 95% confidence interval (CI) 1.14-6.94). This association was not seen after adjustment for age, simplified acute physiology score (SAPS II), and inappropriate empiric antibiotic therapy. Inappropriate empiric therapy (adjusted OR 3.86, 95% CI 1.32-11.31) and SAPS II score (adjusted OR 1.09, 95% CI 1.02-1.16) were significantly associated with treatment failure in the multivariate analysis.

CONCLUSIONS

Third-generation cephalosporin-resistant Enterobacter bacteremia is associated with treatment failure due to receipt of inappropriate empiric antibiotic therapy and severity of illness.

Comparison of chest radiograph scoring to lung weight as a quantitative index of pulmonary edema in organ donors

Quantification of the degree of pulmonary edema in organ donors is useful for assessing the clinical severity of pulmonary edema, determining response to therapy, and as an endpoint for therapeutic trials. Currently, there is no accurate non-invasive method for assessing the degree of pulmonary edema. We tested the performance of a four-quadrant chest radiographic scoring system compared to quantification of pulmonary edema by excised lung weight in 84 donors whose lungs were not used for transplantation. Chest radiographs were taken 3.6 ± 3.0 h prior to organ procurement and were scored by two of the authors. Lungs were excised without perfusion and individually weighed. The chest radiographic scoring system had good performance: correlation between total radiographic score and total lung weight of 0.61, p < 0.001. Performance of the scoring system was improved when chest radiographs with atelectasis were excluded (r = 0.79, p < 0.001). The area under the receiver operator characteristic curve for the detection of moderate pulmonary edema (total lung weight >1000 g) was 0.80. This chest radiographic scoring system may potentially be used to assess the clinical severity of pulmonary edema and may be useful as part of the evaluation of donors for suitability for lung transplantation.

Comparison of pleural fluid N-terminal pro-brain natriuretic peptide and brain natriuretic-32 peptide levels

BACKGROUND

Current evidence indicates that measurement of pleural fluid N-terminal pro-brain natriuretic peptide (NT-proBNP) levels can aid in distinguishing pleural effusions of cardiac origin from those of noncardiac origin. To date, only one study, to our knowledge, has described simultaneous measurement of pleural fluid brain natriuretic-32 peptide (BNP) and NT-proBNP. The purpose of the present study was to determine pleural fluid BNP and NT-proBNP levels and analyze the relationship between these two measurements. We hypothesized that there would be a positive correlation between pleural fluid NT-proBNP and BNP, whereas NT-proBNP levels would be higher than BNP levels.

METHODS

Levels of pleural fluid NT-proBNP and BNP were measured by enzyme immunoassay in a total of 80 patients: 20 with congestive heart failure, 20 status post-coronary artery bypass graft, 20 with carcinoma, and 20 with pneumonia.

RESULTS

Comparison of NT-proBNP and BNP concentrations using the Spearman method of statistical analysis revealed a correlation coefficient of 0.572, P < .001. Evaluation of the diagnostic accuracy of BNP and NT-proBNP in patients with pleural effusions of cardiac origin demonstrated an area under the receiver operating characteristic curve of 0.700 (95% CI, 0.569-0.831) and 0.835 (95% CI, 0.721-0.949), respectively.

CONCLUSIONS

Although levels of pleural fluid BNP have a statistically significant correlation with those of NT-proBNP, this relationship only explains 32% of the variance in NT-proBNP levels. Furthermore, when compared with BNP, NT-proBNP is a more accurate diagnostic aid in the evaluation of pleural effusions of cardiac origin.