In vitro activity of ceftazidime-avibactam and comparators against OXA-48-like Enterobacterales collected between 2016 and 2020

Oxacillinases (OXA)-48-like β-lactamases are one of the most common resistance determinants among carbapenem-resistant Enterobacterales reported globally. Moreover, there is no standard treatment available against organisms producing OXA-48-like enzymes, and they are sometimes difficult to detect, making treatment challenging. The objective of this study was to evaluate the distribution and antimicrobial susceptibility of blaOXA-48-like Enterobacterales isolates against ceftazidime-avibactam (CAZ-AVI) and a panel of comparators collected worldwide from 2016 to 2020 as a part of the Antimicrobial Testing Leadership and Surveillance program. Among all the Enterobacterales isolates collected, 1.8% (1,690/94,052) carried blaOXA-48-like, and a majority of those were identified as K. pneumoniae (86.5%, 1,462/1,690). Among all the blaOXA-48-like isolates, 88.9% (1,502/1,690) were extended-spectrum β-lactamase (ESBL)-positive, 20.7% (350/1,690) were metallo-β-lactamase (MBL)-positive, and 8.9% (150/1,690) were ESBL- and MBL-negative. There were 10 different variants of the OXA-48-like family of enzymes detected, with the major variant being blaOXA-48 (50.2%, 848/1,690), blaOXA-232 (29.3%, 496/1,690), and blaOXA-181 (18.0%, 304/1,690). Overall, all the blaOXA-48-like isolates showed a susceptibility of 78.6% to CAZ-AVI. Importantly, high susceptibility to CAZ-AVI was shown by all the blaOXA-48 type, MBL-negative isolates (n = 1,380, ≥99.0%), and all the MBL-negative isolates (n = 1,300, ≥97.6%) of the major variants (blaOXA-48, blaOXA-232, and blaOXA-181) studied. Among the comparator agents, all isolates showed good susceptibility to only tigecycline (>95.0%) and colistin (>78.6%). Considering the limited treatment options available, CAZ-AVI could be considered as a potential treatment option against blaOXA-48-like Enterobacterales. However, routine surveillance and appropriate stewardship strategies for these organisms may help identify emerging resistance mechanisms and effective treatment of infections.

IMPORTANCE

Resistance to carbapenems among Enterobacterales is often due to the production of enzymes that are members of the oxacillinases (OXA)-48-like family. These organisms can also be resistant to other classes of drugs and are difficult to identify and treat. This study evaluated the activity of the drug ceftazidime-avibactam (CAZ-AVI) and other comparator agents against a global collection of Enterobacterales that produce OXA-48-like enzymes. CAZ-AVI was active against blaOXA-48-like Enterobacterales, and only colistin and tigecycline were similarly active among the comparator agents, highlighting the limited treatment options against these organisms. Continued surveillance of the distribution of these OXA 48-like producing Enterobacterales and monitoring of resistance patterns along with the implementation of antimicrobial stewardship measures to guide antibiotic use and appropriate treatment are necessary to avoid drug resistance among these organisms.

1707. In vitro Activities of Ceftazidime-Avibactam and Comparator Agents against Enterobacterales and Pseudomonas aeruginosa Collected < 48 Hours and ≥48 Hours Post-Admission from Hospitalized Adult Patients, ATLAS Global Surveillance Program 2017-2020

Background

Effective treatments for Gram-negative infections have dwindled with the emergence and dissemination of multi-drug resistant Enterobacterales (Ent) and Pseudomonas aeruginosa (Psa). Fortunately, ceftazidime-avibactam (CAZ-AVI) has activity against Ent and Psa isolates that produce Class A, C and some Class D β-lactamases. This study examined the in vitro activity of CAZ-AVI and comparators against Ent and Psa from presumed community-acquired (CA; cultured < 48 h after hospital admission) and hospital-acquired (HA; cultured ≥48 h post-admission) infections collected from adult patients as part of the ATLAS surveillance program, 2017-2020.

Methods

59,904 non-duplicate Ent and 2,504 Psa isolates from adult patients (≥18 y.o.) were collected from 271 sites in 57 countries as part of ATLAS 2017-2020 (excluding North America) for which the length of hospitalization stay was specified. Antimicrobial susceptibility testing was by broth microdilution according to CLSI guidelines and analyzed using CLSI 2022 breakpoints. Ent isolates testing with meropenem MICs >1 µg/mL and Escherichia coli, Klebsiella pneumoniae, K. oxytoca, K. variicola, and Proteus mirabilis testing with ceftazidime and/or aztreonam MICs >1 mg/L were genetically screened for β-lactamases. For Psa, meropenem MIC >2 µg/mL triggered β-lactamase screening. In 2020, approximately 25% of the meropenem non-susceptible isolates were screened.

Results

For Ent, CAZ-AVI was the most active agent examined against both the CA- and HA-infection population of isolates. The percentage of Ent isolates susceptible to CAZ-AVI was 2.6% and 5.3% higher compared to meropenem for the CA- and HA-infection sets, respectively. Considering both the CA- and HA- infection Psa isolates, CAZ-AVI was also the most active agent among comparators, showing %S rates 12.8% and 19.3% higher than meropenem, respectively.

Conclusion

Against Ent and Psa from adult patients, CAZ-AVI exhibited excellent in vitro activity regardless of whether the pathogen was isolated < 48 hrs. or ≥48 hrs. post hospital admission. The slightly decreased susceptibility to CAZ-AVI for the HA Psa isolates as compared to the CA isolates, as well as the relatively low %S rates for comparators, reinforces difficult-to-treat nature of nosocomial infections.

Disclosures

All Authors: No reported disclosures.

1710. In Vitro Activity of Cefepime-Taniborbactam and Comparators Against a Global Collection of Carbapenem-Resistant Enterobacterales and Carbapenem-Resistant Pseudomonas aeruginosa With and Without Carbapenemases

Background

Carbapenem-resistant Enterobacterales (CRE) and P. aeruginosa (CRPA) present treatment difficulties owing to numerous possible resistance mechanisms, including the carriage of carbapenemases. Taniborbactam is a novel cyclic boronate-based broad-spectrum β-lactamase inhibitor with activity against serine-, and NDM & VIM metallo-β-lactamases (Ambler Classes A, B, C and D). The activity of the investigational combination cefepime-taniborbactam (FTB) and comparator agents was evaluated against a recent global collection of carbapenemase and non-carbapenemase producing CRE and CRPA.

Methods

13,731 Enterobacterales and 4,619 P. aeruginosa isolates collected from 56 countries in 2018-2020 were a part of this study. MICs of cefepime with taniborbactam fixed at 4 µg/mL and comparators were determined according to CLSI guidelines and interpreted using 2022 CLSI breakpoints. CRE and CRPA were defined by resistance to meropenem. Organisms with FTB MIC ≥16 µg/mL were characterized by whole genome sequencing, while those resistant to meropenem were screened for acquired β-lactamase carriage by multiplex PCR followed by Sanger sequencing.

Results

Among the 637 CRE identified, 596 were found to carry a carbapenemase while the remaining 41 did not. For the carbapenemase-positive CRE, 89.8% and 94.5% of isolates were inhibited at ≤8 µg/mL and ≤16 µg/mL FTB, respectively, both values significantly greater than comparators (Table). For carbapenemase-negative CRE, 92.7% of isolates were inhibited at ≤8 µg/mL FTB, and 95.1% were inhibited at ≤16 µg/mL, again higher %s than comparators. Against carbapenemase-negative CRPA (n=703), FTB was the most active agent among the comparators, with 82.6% inhibited at ≤8 µg/mL and 94.9% inhibited at ≤16 µg/mL. Versus CRPA carrying carbapenemases (n=245), 61.9% were inhibited at ≤8 µg/mL FTB and 72.5% were inhibited at ≤16 µg/mL FTB.

Conclusion

FTB displayed substantial in vitro activity against CRE and CRPA regardless of whether they harbored carbapenemases. More isolates of each group were inhibited by FTB at ≤8 µg/mL than were susceptible to all tested β-lactam/β-lactamase inhibitor combinations. These data support the continued development of FTB as a potential new therapeutic antibacterial agent.

Disclosures

All Authors: No reported disclosures.

1708. In vitro Activities of Ceftazidime-Avibactam and Comparator Agents against Enterobacterales and Pseudomonas aeruginosa Collected < 48 Hours and ≥48 Hours Post-Admission from Hospitalized Pediatric Patients, ATLAS Global Surveillance Program 2017-2020

Background

Ceftazidime-avibactam (CAZ-AVI) is a β-lactam combined with a diazabicyclooctane-β-lactamase inhibitor for treatment of infections caused by Gram-negative pathogens. Ceftazidime-avibactam is active against Enterobacterales (Ent) and P. aeruginosa (Psa) isolates that produce Class A, C and some Class D β-lactamases. This study examined the in vitro activity of CAZ-AVI and comparators against Ent and Psa from presumed community-acquired (CA; cultured < 48 h after hospital admission) and hospital-acquired (HA; cultured ≥48 h post-admission) infections collected from pediatric patients as part of the ATLAS surveillance program, 2017-2020.

Methods

5765 non-duplicate Ent and 1987 Psa isolates from pediatric patients (≤17 y.o.) were collected from 241 sites in 54 countries as part of ATLAS 2017-2020 (excluding North America) for which the length of hospitalization stay was specified. Antimicrobial susceptibility testing was by broth microdilution according to CLSI guidelines and analyzed using CLSI 2022 breakpoints. Ent isolates testing with meropenem MICs >1 µg/mL and Escherichia coli, Klebsiella pneumoniae, K. oxytoca, K. variicola, and Proteus mirabilis testing with ceftazidime and/or aztreonam MICs >1 mg/L were genetically screened for β-lactamases. For Psa, meropenem MIC >2 µg/mL triggered β-lactamase screening. In 2020, approximately 25% of the meropenem non-susceptible isolates were screened.

Results

Against Ent, the in vitro activity of CAZ-AVI exceeded that of meropenem and other tested agents for both the presumed CA- and HA-infection sets. The addition of AVI to CAZ increased the %S from 76.1% to 97.5% for the CA-infection population, and from 62.2% to 96.1% for the HA-infection population. For Psa There was a larger difference between the %S to CAZ-AVI of the presumed CA set (93.3% S) and the HA set (89.8% S). For both Psa populations, CAZ-AVI was the most active drug among the comparators.

Conclusion

CAZ-AVI demonstrated potent in vitro activity against Enterobacterales and P. aeruginosa isolates collected globally from pediatric patients in 2017-2020, regardless of whether is infection was community-or hospital-acquired.

Disclosures

All Authors: No reported disclosures.

1709. In Vitro Activity of Ceftazidime-Avibactam and Comparator Agents Against MDR Enterobacterales and Pseudomonas aeruginosa Collected in Latin America, ATLAS Global Surveillance Program 2018-2020

Background

Multidrug-resistant (MDR) Gram-negative bacteria are an increasing worldwide problem. Ceftazidime-avibactam (CAZ-AVI) is a β-lactam/non-β-lactam β-lactamase inhibitor combination that can inhibit class A, C, and some class D β-lactamases, enzymes that contribute to MDR. This study examined the in vitro activity of CAZ-AVI and comparators against MDR Enterobacterales and Pseudomonas aeruginosa isolates collected from patients in Latin America.

Methods

9193 non-duplicate Enterobacterales (Ent) and 3225 P. aeruginosa (Psa) isolates from were collected from 36 sites in 10 Latin American countries as part of ATLAS 2018-2020. Antimicrobial susceptibility testing was by broth microdilution according to CLSI guidelines and analyzed using CLSI 2022 breakpoints. MDR was defined as resistant (R) to ≥3 of 7 sentinel drugs: amikacin (AMK), aztreonam (ATM), cefepime (FEP), colistin (CST), levofloxacin (LVX), meropenem (MEM), and piperacillin-tazobactam (TZP). Ent isolates testing with meropenem MICs >1 µg/mL and Escherichia coli, Klebsiella pneumoniae, K. oxytoca, K. variicola, and Proteus mirabilis testing with ceftazidime and/or aztreonam MICs >1 mg/L were genetically screened for β-lactamases. Psa with meropenem MIC >2 µg/mL were screened in 2018-2019. In 2020, approximately 25% of qualifying Psa were screened.

Results

The activity of CAZ-AVI and comparators against all isolates and the MDR subsets is shown in the table. CAZ-AVI was active against the full collection of Enterobacterales isolates with 96.7% of the population susceptible and an MIC90 value of 1 µg/mL, and maintained considerable activity against the MDR subset, inhibiting 86.5% of the isolates, a value higher than comparator agents. For the full collection of Psa, 86.6% of the isolates were susceptible to CAZ-AVI, again the highest %S among the comparator drugs. Versus the MDR subset of Psa, CAZ-AVI displayed a 45.8% susceptibility rate, approximately 10% higher than the nearest comparator, amikacin.

Conclusion

The in vitro data suggest that CAZ-AVI can be an effective therapeutic for infections caused by MDR Enterobacterales in Latin America. MDR among P. aeruginosa remains challenging, although a significant percentage are inhibited by CAZ-AVI.

Disclosures

All Authors: No reported disclosures.

1672. Antimicrobial Activity of Cefepime-Taniborbactam and Comparators Against Clinical Isolates from ICU and Non-ICU Patients; 2018-2020 Global Surveillance

Background

Taniborbactam is a novel cyclic boronate-based broad-spectrum β-lactamase inhibitor with selective direct inhibitory activity against both serine- and metallo-β-lactamases. Taniborbactam restores the activity of cefepime against many difficult to treat organisms, including cephalosporin- and carbapenem-resistant Enterobacterales (EB) and P. aeruginosa (PA). The activity of cefepime-taniborbactam (FTB) and comparator agents was evaluated against clinical isolates of EB and PA from a 2018-2020 global surveillance study.

Methods

16,742 isolates of EB and PA were collected from patients in wards designated ICU and non-ICU in 2018-2020. MICs of FTB and comparators were determined by the CLSI reference method. Resistant (R) phenotypes were based on 2022 CLSI breakpoints. Multidrug resistant (MDR) was defined as resistance to at least one agent from ≥3 drug classes. Provisional susceptible (S) breakpoints of ≤8 µg/mL and ≤16 µg/mL were applied for FTB for comparative purposes only.

Results

FTB had potent activity against EB, with MIC90s of 0.25 µg/mL for isolates from non-ICU patients and 0.5 µg/mL for isolates from ICU patients (Table). At least 99.2% of all EB from both wards were inhibited by ≤8 µg/mL FTB. FTB maintained activity against R phenotypes of EB in both ward types, with 90.3% to 98.1% of isolates inhibited at ≤8 µg/mL. FTB had potent activity against PA, with MIC90 values of 8 µg/mL and inhibiting ≥94.0% of isolates at ≤8 µg/mL for both ICU and non-ICU isolates. FTB maintained activity against R phenotypes of PA in both ward types, with 71.0% to 83.7% of isolates inhibited at ≤8 µg/mL and 84.7% to 92.5% inhibited at ≤16 µg/mL. %S to comparator agents against the R subsets ranged from 1.6% to 92.6% for EB, and 36.0% to 68.4% for PA. Against the particularly challenging subset of MDR PA from ICU patients, FTB was the most active agent tested as it inhibited 73.5/84.7% of isolates at ≤8/≤16 µg/mL compared to 43.1%S to CZA and 36.0%S to C/T.

Conclusion

Cefepime-taniborbactam demonstrated potent in vitro activity against EB and PA from ICU and non-ICU wards, including resistant subsets of isolates. This supports the continued development of FTB as a potential new treatment option for infections due to resistant Gram-negative pathogens.

Disclosures

All Authors: No reported disclosures.

Oh what a tangled web we weave when first we practice to deceive…

‘Oh what a tangled web we weave when first we practice to deceive’. Marmion, Sir Walter Scott 1808. Conflict is unpleasant, it is aversive, we tend to avoid it. Yet inevitably tension between individuals or between individuals and society is inevitable as the wants of one collide with the purpose of the other. Most of these tensions resolved peacefully but a societal level aggression can sometimes spill out. In the hinterlands between individuals and larger groups these can play out more safely through the courts or sometimes the avoidance of conflict can be the only tactic that the individual can use. As doctors we are used to sing medical problems with patients have true disease believe they have two disease and want to get well-the standard social model of medicine. But sometimes this plays out differently there are those who may fabricate symptoms to avoid punishment or for reward: malingering. There are those who believe they have a disease but the distress is disproportionate to any possible recognised component; somatic symptom disorder. There are those whose anxiety about whether they have a disease or not is paralysing and perhaps most distressing for all of the groups who self-harm or malinger with authentic illness or disease. In this talk Dr Wise will, using case examples, look at a couple of the tools that exist to assist psychiatrists in piloting a pathway through the stormy waters of abnormal illness in litigation.

Diagnostic dilemma’s in the new world of ICD-11 personality disorders

Personality disorders have ever been a troublesome group. From the early 90’s ICD 10 tidied up the group. DSM-IV, IV-TR, aand then DSM 5, changed the style but not substance, leaving clinicians to grapple with thorny questions of multiple diagnoses, treatment and prognosis. International views on the utility of the diagnosis often depended upon the institution or the funding mechanism. Were fears of exclusion and stigma dominated or where there was no treatment, there was under-diagnosis, such as in the United Kingdom and the Republic of Ireland. Where a label was a ticket of entry to treatment and funding, diagnostic generosity prevailed, such as in Australia, New Zealand and the United States. Gender discrepancies disappeared with structured interviews, and interest grew in the category which seem to only include the most severe forms. For many years the DSM taskforce tried to shift the construct but shied away from the cliff edge; a bold new initiative did not materialise. It was left to the ICD-11 to generate a much more adventurous and positive view of how characterological traits shift under pressure, moving from something that may at first have helped patients to ‘survive’ to something that became maladaptive and harmful. With a court tested case Dr Wise will demonstrate the differences between ICD-10 and ICD-11 highlighting the more important differences: onset, course and severity descriptors. PD’s are no longer lifelong impairments. Prepare for ‘The shock of the new’!

Molecular characterization of clinical isolates of Enterobacterales with elevated MIC values for aztreonam-avibactam from the INFORM global surveillance study, 2012-2017

OBJECTIVES

While aztreonam-avibactam is a potent β-lactam-β-lactamase-inhibitor combination, reduced in vitro activity against some Enterobacterales isolates has been reported. In this study, globally collected clinical isolates of Enterobacterales with elevated minimum inhibitory concentrations (MICs) for aztreonam-avibactam were examined for potential resistance mechanisms.

METHODS

Isolates with aztreonam-avibactam MICs ≥8 μg/mL (n = 55: Escherichia coli, n = 38; Enterobacter cloacae, n = 10; Klebsiella pneumoniae, n = 3; others, n = 4) and <8 μg/mL (n = 18) collected for the INFORM global surveillance programme were characterized by short read whole-genome sequencing. Sequences were inspected for the presence of β-lactamase genes, penicillin-binding protein (PBP) mutations, and disruptions in the coding sequences of porin genes.

RESULTS

All isolates of E. coli testing with aztreonam-avibactam MIC values ≥8 μg/mL carried a previously documented four-amino-acid insertion in PBP3 at position 333 of YRI(K/N/P). Such mutations were absent in isolates with MICs <2 μg/mL (n = 6). Among other species, carriage of PER- or VEB-type β-lactamases was identified in 10/17 (58.8%) of isolates testing with aztreonam-avibactam MICs ≥8 μg/mL, but no isolates with lower MIC values (n = 11).

CONCLUSIONS

PBP3 mutations are known to confer resistance to aztreonam in E. coli, providing a rationale for the elevated MIC values for aztreonam-avibactam in these isolates. Elevated MICs in other isolates were associated with the carriage of PER-type β-lactamases, which have been previously shown to be inhibited less effectively by avibactam than other Class A β-lactamases and may contribute to this phenotype. Other resistance mechanisms contributing to poor in vitro activity for aztreonam-avibactam in some of these isolates are not yet elucidated.

Detecting national human enteric disease outbreaks linked to animal contact in the United States of America

Enteric pathogens, such as non-typhoidal Salmonella, Campylobacter and Escherichia coli, can reside in the intestinal tract of many animals, including livestock, companion animals, small mammals and reptiles. Often, these animals can appear healthy; nonetheless, humans can become infected after direct or indirect contact, resulting in a substantial illness burden. An estimated 14% of the 3.2 million illnesses that occur in the United States of America (USA) each year from such enteric pathogens are attributable to animal contact. Surveillance for enteric pathogens in the USA includes the compilation and interpretation of both laboratory and epidemiologic data. However, the authors feel that a collaborative, multisectoral and transdisciplinary - or One Health - approach is needed for data collection and analysis, at every level. In addition, they suggest that the future of enteric illness surveillance lies in the development of improved technologies for pathogen detection and characterisation, such as genomic sequencing and metagenomics. In particular, using whole-genome sequencing to compare genetic sequences of enteric pathogens from humans, food, animals and the environment, can help to predict antimicrobial resistance among these pathogens, determine their genetic relatedness and identify outbreaks linked to a common source. In this paper, the authors describe three recent, multi-state human enteric illness outbreaks linked to animal contact in the USA and discuss how integrated disease surveillance was essential to outbreak detection and response. Additional datasharing between public health and animal health laboratories and epidemiologists at the local, national, regional and international level may help to improve surveillance for emerging animal and human health threats and lead to new opportunities for prevention.

0408 Myths About Infant, Child, and Adolescent Sleep: Addressing False Beliefs That Hinder Sleep Health During These Crucial Developmental Stages

Introduction

Sleep is vital for healthy development from infancy through adolescence. Despite its importance, false beliefs that conflict with scientific evidence (myths) may be common among caregivers and impair sleep health during these crucial stages.

Methods

Researchers compiled a list of potential myth statements using internet searches of popular press and scientific literature. We utilized a Delphi process with experts (n=12) from the fields of pediatric, sleep, and circadian research and clinical practice. Selection and refinement of myths by sleep experts proceeded in three phases, including: focus groups (Phase 1); email-based feedback to edit, add, or remove myths (Phase 2); and closed-ended questionnaires (Phase 3) where experts rated myths on two dimensions: (1) falseness and (2) public health significance using 5-point Likert scale: 1 (“not at all”) to 5 (“extremely false/important”).

Results

Thirty-two sleep myths were identified across three developmental categories: infant (14 myths), child (6 myths), and adolescent (12 myths). Mean expert ratings illuminated the most pressing myths in each developmental category: infant sleep (“Sleep training causes psychological harm, including reduced parent-child attachment:” falseness =4.7, s.d.=0.7; public health significance=4.0, s.d.=1.1); child sleep (“Heavy, loud snoring for my child means he’s sleeping deeply:” falseness=4.8, s.d.=0.6; public health significance=4.7, s.d.=0.7), and teenager sleep (“Falling asleep in class means your teenager is lazy and not motivated:” falseness=4.8, s.d.=0.5; public health significance=4.3, s.d.=0.8).

Conclusion

The current study identified commonly-held myths about infant, child, and adolescent sleep that are not supported by (or worse, counter to) scientific evidence. If unchecked, these myths may hinder sleep at a critical developmental stage. Future research may include public health education to correct myths and promote healthy sleep among infants, children, and teenagers.

Support

5T32HL007901

A radio ridge connecting two galaxy clusters in a filament of the cosmic web

Galaxy clusters are the most massive gravitationally bound structures in the Universe. They grow by accreting smaller structures in a merging process that produces shocks and turbulence in the intracluster gas. We observed a ridge of radio emission connecting the merging galaxy clusters Abell 0399 and Abell 0401 with the Low-Frequency Array (LOFAR) telescope network at 140 megahertz. This emission requires a population of relativistic electrons and a magnetic field located in a filament between the two galaxy clusters. We performed simulations to show that a volume-filling distribution of weak shocks may reaccelerate a preexisting population of relativistic particles, producing emission at radio wavelengths that illuminates the magnetic ridge.

1358. In vitro Activity of Ceftazidime–Avibactam and Comparator Agents Against Pseudomonas aeruginosa Causing Intra-Abdominal, Lower Respiratory, and Urinary Tract Infections Collected in Latin America as Part of the INFORM Global Surveillance Program, 2012–2016

Background

Methods

Results

Conclusion

Disclosures

Lactate, lactate clearance and outcome after cardiac arrest: A post-hoc analysis of the TTM-Trial

BACKGROUND

Admission lactate and lactate clearance are implemented for risk stratification in sepsis and trauma. In out-of-hospital cardiac arrest, results regarding outcome and lactate are conflicting.

METHODS

This is a post-hoc analysis of the Target Temperature Management trial in which 950 unconscious patents after out-of-hospital cardiac arrest were randomized to a temperature intervention of 33°C or 36°C. Serial lactate samples during the first 36 hours were collected. Admission lactate, 12-hour lactate, and the clearance of lactate within 12 hours after admission were analyzed and the association with 30-day mortality assessed.

RESULTS

Samples from 877 patients were analyzed. In univariate logistic regression analysis, the odds ratio for death by day 30 for each mmol/L was 1.12 (1.08-1.16) for admission lactate, P < .01, 1.21 (1.12-1.31) for 12-hour lactate, P < .01, and 1.003 (1.00-1.01) for each percentage point increase in 12-hour lactate clearance, P = .03. Only admission lactate and 12-hour lactate levels remained significant after adjusting for known predictors of outcome. The area under the receiver operating characteristic curve was 0.65 (0.61-0.69), P < .001, 0.61 (0.57-0.65), P < .001, and 0.53 (0.49-0.57), P = .15 for admission lactate, 12-hour lactate, and 12-hour lactate clearance, respectively.

CONCLUSIONS

Admission lactate and 12-hour lactate values were independently associated with 30-day mortality after out-of-hospital cardiac arrest while 12-hour lactate clearance was not. The clinical value of lactate as the sole predictor of outcome after out-of-hospital cardiac arrest is, however, limited.

Activity of Ceftazidime–Avibactam Against Respiratory Isolates of Enterobacteriaceae and Pseudomonas aeruginosa Collected in Asia/Pacific as part of the INFORM Global Surveillance Program, 2014–2016

Background

Avibactam (AVI) is a non-β-lactam β-lactamase inhibitor that restores the in vitro activity of ceftazidime (CAZ) against class A, class C, and some class D β-lactamases, including extended-spectrum β-lactamases, serine carbapenemases, and the chromosomal AmpC of Pseudomonas aeruginosa (Pae). This study evaluated the in vitro activity of CAZ-AVI and comparators against Enterobacteriaceae (Eba) and Pae collected from patients with lower respiratory tract infections (LRTI) in Asia/Pacific in 2014–2016 as part of the INFORM surveillance program.

Methods

Non-duplicate isolates from patients with LRTI were collected from 28 medical centers in Australia, Hong Kong, Japan, Malaysia, Philippines, South Korea, Taiwan, and Thailand. Susceptibility (S) testing was performed by broth microdilution and interpreted using FDA breakpoints for CAZ-AVI and CLSI breakpoints for comparators. AVI was tested at a fixed concentration of 4 µg/mL with doubling dilutions of CAZ. Multidrug resistance (MDR) phenotype was defined as resistant by CLSI breakpoints to sentinel agents from ≥3 drug classes.

Results

CAZ-AVI showed potent in vitro activity against the overall population of Eba (MIC₉₀, 0.5 µg/mL; 98.0% S) and against ceftazidime-nonsusceptible (CAZ-NS), colistin-resistant (CST-R), and MDR isolates, with >91% of these resistant subsets testing as susceptible (MIC ≤8 µg/mL). Reduced activity against meropenem-nonsusceptible (MEM-NS) Eba was attributable to the presence of class B metallo-β-lactamases (MBL); 95.7% of MEM-NS, MBL-negative isolates were susceptible to CAZ-AVI. CAZ-AVI also showed good activity against most Pae isolates (MIC₉₀, 8 µg/mL; 92.5% S), as well as CST-R isolates (MIC₉₀, 8 µg/mL; 100% S). Activity of CAZ-AVI was reduced against CAZ-NS, MEM-NS, MEM-NS MBL-negative, and MDR Pae subsets (46.9–82.3% S) but exceeded the activity of CAZ and MEM.

Conclusion

CAZ-AVI is a potential therapeutic option for treating respiratory infections in the Asia/Pacific region caused by Eba and Pae isolates resistant to commonly used and last-in-line agents.

Disclosures

G. G. Stone, Pfizer: Employee, Salary AstraZeneca: Shareholder, Capital Gains

Chemoradiotherapy for squamous cell anal carcinoma: a review of prognostic factors

AIM

Previous literature has sought prognostic factors for the survival of anal cancer patients. The present study aimed to determine prognostic factors for local disease recurrence, distant metastasis and survival for patients treated with radical chemoradiotherapy (CRT) at the Rosemere Cancer Centre, Preston, UK.

METHOD

Patients treated with CRT for nonmetastatic squamous cell anal cancer between September 2000 and January 2013 were studied. Kaplan-Meier and Cox regression analysis assessed the prognostic value of age, sex, tumour size, the proportion of the anal canal circumference involved (ACCI), nodal disease, tumour location and pretreatment haemoglobin.

RESULTS

One hundred and 48 patients with a mean age of 63 years were studied, of whom 15% suffered local disease recurrence and 10% developed distant metastasis. The 5-year overall and cancer-specific survival rates were 84% and 86%, respectively. Predictors of local recurrence were tumour size >5 cm and over two-thirds ACCI (P < 0.01). Predictors of distant metastasis and poor survival were tumour size >5 cm (P < 0.01), node positive disease on imaging (P < 0.05), over two-thirds ACCI (P < 0.01) and a pretreatment haemoglobin level below 130 g/l (P < 0.05). Multivariate analysis found large tumour size to be the most significant factor for local recurrence (P = 0.002) and survival (P = 0.02) whilst over two-thirds ACCI was most predictive of distant metastasis (P < 0.001). Age, gender, palpable lymph nodes and tumour location were not of prognostic value for local disease recurrence, distant metastasis or survival.

CONCLUSION

Tumour size, nodal disease, over two-thirds ACCI and low pretreatment haemoglobin confer poorer prognostic and survival outcomes. Use of intensity-modulated radiation therapy may allow greater radiation doses to be given for locally advanced tumours, thus improving local control and survival and reducing morbidity.

New methods to constrain the radio transient rate: results from a survey of four fields with LOFAR

We report on the results of a search for radio transients between 115 and 190 MHz with the LOw-Frequency ARray (LOFAR). Four fields have been monitored with cadences between 15 min and several months. A total of 151 images were obtained, giving a total survey area of 2275 deg². We analysed our data using standard LOFAR tools and searched for radio transients using the LOFAR Transients Pipeline. No credible radio transient candidate has been detected; however, we are able to set upper limits on the surface density of radio transient sources at low radio frequencies. We also show that low-frequency radio surveys are more sensitive to steep-spectrum coherent transient sources than GHz radio surveys. We used two new statistical methods to determine the upper limits on the transient surface density. One is free of assumptions on the flux distribution of the sources, while the other assumes a power-law distribution in flux and sets more stringent constraints on the transient surface density. Both of these methods provide better constraints than the approach used in previous works. The best value for the upper limit we can set for the transient surface density, using the method assuming a power-law flux distribution, is 1.3 × 10^-3 deg^-2 for transients brighter than 0.3 Jy with a time-scale of 15 min, at a frequency of 150 MHz. We also calculated for the first time upper limits for the transient surface density for transients of different time-scales. We find that the results can differ by orders of magnitude from previously reported, simplified estimates.

Assessment for possible healthcare-associated transmission of a new variant influenza virus--Pennsylvania, August 2011

In August 2011, one of the earliest cases of influenza A(H3N2) variant [A(H3N2)v] virus infection was hospitalized with severe illness. To investigate the potential for healthcare-associated transmission of influenza A(H3N2)v, we evaluated both healthcare providers and patient contacts of the case. We found that healthcare-associated transmission was unlikely.

MESAFace, a graphical interface to analyze the MESA output

MESA (Modules for Experiments in Stellar Astrophysics) has become very popular among astrophysicists as a powerful and reliable code to simulate stellar evolution. Analyzing the output data thoroughly may, however, present some challenges and be rather time-consuming. Here we describe MESAFace, a graphical and dynamical interface which provides an intuitive, efficient and quick way to analyze the MESA output.

NATURE OF PROBLEM

Find a way to quickly and thoroughly analyze the output of a MESA run, including all the profiles, and have an efficient method to produce graphical representations of the data.

SOLUTION METHOD

We created two scripts (to be run consecutively). The first one downloads all the data from a MESA run and organizes the profiles in order of age. All the files are saved as tables or arrays of tables which can then be accessed very quickly by Mathematica. The second script uses the Manipulate function to create a graphical interface which allows the user to choose what to plot from a set of menus and buttons. The information shown is updated in real time. The user can access very quickly all the data from the run under examination and visualize it with plots and tables.

UNUSUAL FEATURES

Moving the slides in certain regions may cause an error message. This happens when Mathematica is asked to read nonexistent data. The error message, however, disappears when the slides are moved back. This issue does not preclude the good functioning of the interface.

ADDITIONAL COMMENTS

The program uses the dynamical capabilities of Mathematica. When the program is opened, Mathematica prompts the user to "Enable Dynamics". It is necessary to accept before proceeding.

RUNNING TIME

Depends on the size of the data downloaded, on where the data are stored (hard-drive or web), and on the speed of the computer or network connection. In general, downloading the data may take from a minute to several minutes. Loading directly from the web is slower. For example, downloading a 200MB data folder (a total of 102 files) with a dual-core Intel laptop, P8700, 2 GB of RAM, at 2.53 GHz took about a minute from the hard-drive and about 23 minutes from the web (with a basic home wireless connection).

A psychotherapy program for soldiers dependents: The effect on recall rates. “They are not going for three weeks and the fighting has already begun!”

Introduction

Deployment to conflict areas poses problems for service families. These stressors pose a high cost from increased rates of marital/family break-up and the impact on operational effectiveness, through early recall from combat zones. Soldiers look forward to a mission whilst partners are more ambivalent. The time before deployment is hard on those who stay behind, who experience high levels of anxiety. Those about to be deployed feel guilty, and have to manage their own anxieties about what the mission will bring - hard work, excitement and danger. Most do not talk about this to their partners, who in turn have to manage their own inner turmoil and worst case ‘fantasies’.

Aims

The project grew from concerns about the welfare of families of deployed army personnel.

Objectives

The project aimed to help them develop a greater capacity to manage, contain and function with these worries. The program provided psychodynamic psychoanalytic practices to a previously neglected group that was not wholly army, but is essential to its well-being.

Methods

The program gave the families a greater understanding of the emotional difficulties faced by their partners before, during and after deployment and lessened the stress in their relationships; strengthening their own and their partners’ sense of self, resilience, and the marital bond.

Results

Usually 3–5% of a unit would be recalled from combat operations, over the duration of a tour, this was reduced to 1%.

Conclusion

A psychotherapy programme for the families of soldiers reduces attrition rates.