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Background:Burkholderia multivorans are gram-negative bacteria typically found in water and soil. B. multivorans outbreaks among patients without cystic fibrosis have been associated with exposure to contaminated medical devices or nonsterile aqueous products. Acquisition can also occur from exposure to environmental reservoirs like sinks or other hospital water sources. We describe an outbreak of B. multivorans among hospitalized patients without cystic fibrosis at 2 hospitals within the same healthcare system in California (hospitals A and B) between August 2021 and July 2022. Methods: We defined confirmed case patients as patients without cystic fibrosis hospitalized at hospital A or hospital B between January 2020 to July 2022 with B. multivorans isolated from any body site matching the outbreak strain. We reviewed medical records to describe case patients and to identify common exposures. We evaluated infection control practices and interviewed staff to detect exposures to nonsterile water. Select samples from water, ice, drains, and sink splash zone surfaces were collected and cultured for B. multivorans in March 2022 and July 2022 from both hospitals. Common aqueous products used among case patients were tested for B. multivorans. Genetic relatedness between clinical and environmental samples was determined using random amplified polymorphic DNA (RAPD) and repetitive extragenic palindromic polymerase chain reaction (Rep-PCR). Results: We identified 23 confirmed case patients; 20 (87%) of these were identified at an intensive care unit (ICU) in hospital A. B. multivorans was isolated from respiratory sources in 18 cases (78%). We observed medication preparation items, gloves, and patient care items stored within sink splash zones in ICU medication preparation rooms and patient rooms. Nonsterile water and ice were used for bed baths, swallow evaluations, and ice packs. B. multivorans was cultured from ice and water dispensed from an 11-year-old ice machine in the ICU at hospital A in March 2022 but no other water sources. Additional testing in July 2022 yielded B. multivorans from ice and a drain pan from a new ice machine in the same ICU location at hospital A. All products were negative. Clinical and environmental isolates were the same strain by RAPD and Rep-PCR. Conclusions: The use of nonsterile water and ice from a contaminated ice machine contributed to this outbreak. Water-related fixtures can serve as reservoirs for Burkholderia, posing infection risk to hospitalized and immunocompromised patients. During outbreaks of water-related organisms, such as B. multivorans , nonsterile water and ice use should be investigated as potential sources of transmission and other options should be considered, especially for critically ill patients.
Objectives: To address the importation of multi-drug-resistant organisms (MDROs) when a colonized or infected patient is transferred from another VA facility, the Veterans Health Administration (VHA) launched the Inpatient Pathogen Tracker (IPT) in 2020. IPT tracks MDRO-infected/colonized patients and alerts MDRO Program Coordinators (MPCs) and Infection Preventionists (IPs) when such patients are admitted to their facility to facilitate rapid identification and isolation of infected/colonized patients. IPT usage has been low during initial rollout (32.5%). The VHA and the CARRIAGE QUERI Program developed targeted implementation strategies to increase utilization of IPT’s second iteration, VA Bug Alert (VABA). Methods: Familiarity with IPT was assessed via pre-education survey (3/2022). All sites received standard VABA implementation including: 1) adaptation of VABA features based on end-user feedback (completed 4/2022), 2) development and delivery of an educational module regarding the revised tool (completed 4/2022), and 3) internal facilitation from the VHA MDRO Program Office (ongoing) (see Figure for all key timepoints). Intent to register for VABA was assessed via post-education survey (4-5/2022). Sites (125 eligible) not registered for VABA by 6/1/2022 were randomly assigned to receive one of two conditions from 6/2022–8/2022: continued standard implementation alone or enhanced implementation. Enhanced implementation added the following to standard implementation: 1) audit and feedback reports and 2) external facilitation, including interviews and education about VABA. We compared the number of sites with ≥1 MPC/IP registered for VABA to-date between implementation conditions. Results:Pre-education survey. 168 MPC/IPs across 117 sites responded (94% of eligible sites). Among respondents, 25% had used IPT, 35.1% were familiar with but had not used IPT, and 39.9% were unfamiliar with IPT. Post-education survey. 93 MPC/IPs across 80 sites responded (59% of eligible sites). Of these, 81.7% said they planned to register for VABA, 4.3% said they would not register, and 14.0% said they were unsure. Post-6/1/2022 Registrations. By 6/1/2022, 71% of sites had ≥1 registered VABA user. Of the 28 unregistered sites eligible for enhanced implementation, thirteen were assigned to receive enhanced implementation, and fifteen were assigned to receive continued standard implementation. Eight sites in the enhanced implementation condition (61.5%) registered for VABA. Seven standard-implementation-only sites (46.7%) registered. The number of registered sites did not significantly differ by implementation condition (Fisher’s exact p=0.476). Conclusions: Standard and enhanced implementation were equally effective at encouraging VABA registration, suggesting that allocating resources to enhanced implementation may not be necessary.
The relationship between pitch-naming ability and childhood onset of music training is well established and thought to reflect both genetic predisposition and music training during a critical period. However, the importance of the amount of practice during this period has not been investigated. In a population sample of twins (N = 1447, 39% male, 367 complete twin pairs) and a sample of 290 professional musicians (51% male), we investigated the role of genes, age of onset of playing music and accumulated childhood practice on pitch-naming ability. A significant correlation between pitch-naming scores for monozygotic (r = .27, p < .001) but not dizygotic twin pairs (r = −.04, p = .63) supported the role of genetic factors. In professional musicians, the amount of practice accumulated between ages 6 and 11 predicted pitch-naming accuracy (p = .025). In twins, age of onset was no longer a significant predictor once practice was considered. Combined, these findings are in line with the notion that pitch-naming ability is associated with both genetic factors and amount of early practice, rather than just age of onset per se. This may reflect a dose–response relation between practice and pitch-naming ability in genetically predisposed individuals. Alternatively, children who excel at pitch-naming may have an increased tendency to practice.
To describe national trends in testing and detection of carbapenemases
produced by carbapenem-resistant Enterobacterales (CRE) and associate
testing with culture and facility characteristics.
Retrospective cohort study.
Department of Veterans’ Affairs medical centers (VAMCs).
Patients seen at VAMCs between 2013 and 2018 with cultures positive for CRE,
defined by national VA guidelines.
Microbiology and clinical data were extracted from national VA data sets.
Carbapenemase testing was summarized using descriptive statistics.
Characteristics associated with carbapenemase testing were assessed with
Of 5,778 standard cultures that grew CRE, 1,905 (33.0%) had evidence of
molecular or phenotypic carbapenemase testing and 1,603 (84.1%) of these had
carbapenemases detected. Among these cultures confirmed as
carbapenemase-producing CRE, 1,053 (65.7%) had molecular testing for
≥1 gene. Almost all testing included KPC (n = 1,047, 99.4%), with KPC
detected in 914 of 1,047 (87.3%) cultures. Testing and detection of other
enzymes was less frequent. Carbapenemase testing increased over the study
period from 23.5% of CRE cultures in 2013 to 58.9% in 2018. The South US
Census region (38.6%) and the Northeast (37.2%) region had the highest
proportion of CRE cultures with carbapenemase testing. High complexity (vs
low) and urban (vs rural) facilities were significantly associated with
carbapenemase testing (P < .0001).
Between 2013 and 2018, carbapenemase testing and detection increased in the
VA, largely reflecting increased testing and detection of KPC. Surveillance
of other carbapenemases is important due to global spread and increasing
antibiotic resistance. Efforts supporting the expansion of carbapenemase
testing to low-complexity, rural healthcare facilities and standardization
of reporting of carbapenemase testing are needed.
Among 108 (0.05% of cohort) US veterans with a Clostridioides difficile infection (CDI) within 30 days of a dental antibiotic prescription, 80% of patients received guideline-discordant antibiotics. Half had chronic gastrointestinal illness potentially exacerbating their CDI risk. More efforts are needed to improve antibiotic stewardship.
This chapter sets out the field of terrorism studies and reviews the main issues and research directions that characterise the field today. The history of the discipline is summarised and terrorism and its ‘near neighbour’ hate crime are defined and compared before turning to the developments that have dominated the research agenda over the last ten years.
Across the Midwest, substantial funding and personnel time have been allocated to encourage farmers to adopt a wide range of conservation practices but adoption rates for many of these practices remain low. Prior research focuses largely on the influence of individual-level factors (e.g., beliefs, attitudes) on conservation practice adoption rather than on contextual factors (e.g., seasons) that might also play a role. In the present study, we considered seasonal variation and its potential influence on farmer cover crop decision-making. We first established how farmer temporal and financial resources fluctuate across the year and then compared the annual agricultural decision and cover crop decision calendars. We also considered farmer cover crop perceptions and likely behaviors. To study this, we surveyed the same Midwestern farmers in the spring, summer and winter within a 12-month period. Results indicated that farmers were generally the least busy and the most financially comfortable in the winter months. Moreover, farmers perceived the benefits of cover crops differently throughout the year. These results indicate that seasonality can be a confounding factor which should be considered when designing and conducting research and farmer engagement. As researchers, it is our responsibility to understand the specific calendar experienced by our sample and how that may influence responses so we can examine theory-supported factors of interest rather than seasonality as a driver of farmer responses. As practitioners, it is important to use research findings to engage with farmers about conservation in a way that prioritizes communicating about the most salient aspects of the practice at the time of year when farmers will be most receptive.
Ceftazidime/avibactam (C/A), ceftolozane/tazobactam (C/T), imipenem/relebactam (I/R), and meropenem/vaborbactam (M/V) combine either a cephalosporin (C/T and C/A) or a carbapenem antibiotic (M/V and I/R) with a β-lactamase inhibitor. They are used to treat carbapenem-resistant Enterobacterales (CRE) and/or multidrug-resistant Pseudomonas aeruginosa (MDRPA).
We compared the pooled clinical success of these medications to older therapies.
PubMed and EMBASE were searched from January 1, 2012, through September 2, 2020, for C/A, C/T, I/R, and M/V studies. The main outcome was clinical success, which was assessed using random-effects models. Stratified analyses were conducted for study drug, sample size, quality, infection source, study design, and multidrug-resistant gram-negative organism (MDRGNO) population. Microbiological success and 28- and 30-day mortality were assessed as secondary outcomes. Heterogeneity was determined using I2 values.
Overall, 25 articles met the inclusion criteria; 8 observational studies and 17 randomized control trials. We detected no difference in clinical success comparing new combination antibiotics with standard therapies for all included organisms (pooled OR, 1.21; 95% CI, 0.96–1.51). We detected a moderate level of heterogeneity among the included studies I2 = 56%. Studies that focused on patients with CRE or MDRPA infections demonstrated a strong association between treatment with new combination antibiotics and clinical success (pooled OR, 2.20; 95% CI, 1.60–3.57).
C/T, C/A, I/R, and M/V are not inferior to standard therapies for treating various complicated infections, but they may have greater clinical success for treating MDRPA and CRE infections. More studies that evaluate the use of these antibiotics for drug-resistant infections are needed to determine their effectiveness.
We assessed trends in treatment of patients with CRE from 2012 through 2018. We detected decreased utilization of aminoglycosides and colistin and increased utilization in extended-spectrum cephalosporins and ceftazidime-avibactam. We found significant uptake of ceftazidime-avibactam, a newly approved antibiotic, to treat CRE infections.
Background: Gram-negative bacteria cause a variety of hospital-associated infections (HAIs). Of concern is Pseudomonas aeruginosa, which is a leading cause of HAIs. Early and adequate therapy of P. aeruginosa blood stream infection (BSI) is associated with decreased mortality. Additionally, infectious disease consultation has also shown to improve health outcomes, streamline care, and decrease costs. Therefore, the goal of this study was to describe treatment of P. aeruginosa BSI and impact of infectious disease consultations on health outcomes. Methods: In this retrospective cohort study, we analyzed national VA medical, encounter, pharmacy, microbiology, and laboratory data from January 1, 2012 to December 31, 2018. The cohort included all hospitalized adult veterans (aged ≥18 years) who had a positive blood culture for P. aeruginosa. Only the first P. aeruginosa blood culture per patient was included, and duplicate cultures within 30 days were removed. Treatment was identified within −2 to +5 days of the culture date. Multidrug-resistant (MDR) cultures were identified based on resistance to at least 1 agent in at least 3 or more antimicrobial categories tested. Multivariable logistic regression models were fit to assess infectious disease consultations and adequate treatment on in-hospital mortality and 30-day mortality. Results: In total, 3,256 patients had a BSI with P. aeruginosa, of which 386 (11.5%) were MDR. Most of these patients were male (97.5%), >65 years of age (70.9%), and non-Hispanic white (63.8%). Also, 784 patients (23.3%) died during hospitalization and 870 (25.8%) died within 30 days of their culture. In multivariable regression models, infectious disease consultations were associated with decreased odds of in-hospital mortality (odds ratio [OR], 0.64; 95% confidence interval [CI], 0.53–0.77) and 30-day mortality (OR, 0.56, 95% CI, 0.48–0.67) even after adjusting for age, race, care setting, Charlson score, and prior healthcare exposures. Furthermore, inadequate definitive treatment was associated with increased odds of in-hospital mortality (OR, 2.77; 95% CI, 1.35–5.69) and 30-day mortality (OR, 2.37; 95% CI, 1.18–4.79), even after adjusting for age, Charlson score, care setting, and prior healthcare exposures. In addition, carbapenem treatment was associated with increased odds of in-hospital mortality (OR, 1.38; 95% CI, 1.12–1.70) and 30-day mortality (OR, 1.49; 95% CI, 1.22–1.81), whereas fluoroquinolone treatment was associated with lower odds of in-hospital mortality (OR, 0.49; 95% CI, 0.41–0.59) and 30-day mortality (OR, 0.60; 95% CI, 0.50–0.71). Finally, extended-spectrum cephalosporin was also associated with lower odds of in-hospital mortality (OR, 0.82; 95% CI, 0.68–0.98). Conclusions: Use of infectious disease consultations and any adequate definitive treatment for those with P. aeruginosa BSI lowered odds of in-hospital and 30-day mortality. Early consultation with infectious disease physicians regarding adequate treatment has direct positive impact on clinical outcomes for patients with P. aeruginosa BSI.
Background: Infections caused by Acinetobacter spp are often healthcare acquired and associated with high mortality. Extensively drug-resistant (XDR) Acinetobacter are nonsusceptible to at least 1 agent in all but 2 or fewer antibiotic classes. Few of the new antibiotics targeting multidrug-resistant gram-negative bacteria are effective against XDR Acinetobacter. Recent national guidelines for treatment of resistant gram-negative infections do not include Acinetobacter, leaving a knowledge gap in best practices. Methods: This retrospective cohort study included microbiology, clinical, and pharmacy data from all patients hospitalized between 2012 and 2018 at any Veterans’ Affairs medical center who had cultures that grew XDR Acinetobacter spp. Bivariate unadjusted analyses compared clinical outcomes by monotherapy versus combination therapy. Using mixed-effects ordinal logistic regression, propensity score–adjusted models accounting for severity of illness and other variables associated with treatment were fit to compare outcomes. Results: Of 11,546 patients with 15,364 cultures that grew Acinetobacter spp, 408 patients (3.5%) had 666 cultures (4.3%) with XDR Acinetobacter. Moreover, 276 of these patients (67.6%) had gram-negative targeted antibiotic treatment within −2 to +5 days from the culture. Furthermore, 118 patients (42.8%) received monotherapy, most commonly piperacillin-tazobactam (n = 54, 45.7%) or an anti-Pseudomonas cephalosporin (n = 21, 17.8%). Also, 158 (57.2%) patients received combination therapy, most commonly a carbapenem (n = 93, 58.9%) and/or polymyxin (n = 68, 43.0%). Moreover, 41 patients (25.9%) received both a carbapenem and polymyxin. In both unadjusted and adjusted analyses, there were no significant differences in the odds of 30-day mortality (aOR, 1.43; 95% CI, 0.86–2.38) or 1-year mortality (aOR, 1.04; 95% CI, 0.68–1.60) between combination therapy and monotherapy groups. Among 264 patients (96%) whose cultures occurred during an inpatient or long-term care admission, unadjusted analyses showed increased odds of in-hospital mortality (OR, 1.89; 95% CI, 1.08–3.29) and longer postculture length of stay in the combination therapy group: median, 23 days (IQR, 11–57) versus 14 days (IQR, 7–32) (P = .02). However, with propensity score adjustment, these associations were no longer significant. Furthermore, there was no significant difference in odds of 90-day readmission between groups in either unadjusted or adjusted analyses (aOR, 1.20; 95% CI, 0.74–1.95). Conclusions: In this large national cohort of patients with XDR Acinetobacter cultures, more patients received combination therapy than monotherapy, and carbapenems and polymyxins were the most-used classes. However, there were no significant differences in outcomes between patients receiving combination therapy and monotherapy, suggesting lack of clinical benefit to the common practice of treating XDR Acinetobacter infections with multiple antibiotics. Further research is needed to determine optimal treatment strategies for this pathogen.
This is an epidemiological study of carbapenem-resistant Enterobacteriaceae (CRE) in Veterans’ Affairs medical centers (VAMCs). In 2017, almost 75% of VAMCs had at least 1 CRE case. We observed substantial geographic variability, with more cases in urban, complex facilities. This supports the benefit of tailoring infection control strategies to facility characteristics.
Background: Antibiotics are the most prescribed medicines worldwide, accounting for 20%–30% of total drug expenditures in most settings. Antimicrobial stewardship activities can provide guidance for the most appropriate antibiotic use. Objective: In an effort to generate baseline data to guide antimicrobial stewardship recommendations, we conducted point-prevalence surveys at 3 hospitals in Kenya. Methods: Sites included referral hospitals located in Nairobi (2,000 beds), Eldoret (900 beds) and Mombasa (700 beds). [Results are presented in this order.] Hospital administrators, heads of infection prevention and control units, and laboratory department heads were interviewed about ongoing antimicrobial stewardship activities, existing infection prevention and control programs, and microbiology diagnostic capacities. Patient-level data were collected by a clinical or medical officer and a pharmacist. A subset of randomly selected, consenting hospital patients was enrolled, and data were abstracted from their medical records, treatment sheets, and nursing notes using a modified WHO point-prevalence survey form. Results: Overall, 1,071 consenting patients were surveyed from the 3 hospitals (n = 579, n = 263, and n = 229, respectively) of whom >60% were aged >18 years and 53% were female. Overall, 489 of 1,071 of patients (46%) received ≥1 antibiotic, of whom 254 of 489 (52%) received 1 antibiotic, 201 of 489 (41%) received 2 antibiotics, 31 of 489 (6%) received 3 antibiotics, and 3 of 489 (1%) received 4 antibiotics. Antibiotic use was higher among those aged <5 years: 150 of 244 (62%) compared with older individuals (337 of 822, 41%). Amoxicillin/clavulanate was the most commonly used antibiotic (66 of 387, 17%) at the largest hospital (in Nairobi) whereas ceftriaxone was the most common at the other 2 facilities: 57 of 184 (31%) in Eldoret and 55 of 190 (29%) in Mombasa. Metronidazole was the next most commonly prescribed antibiotic (15%–19%). Meropenem was the only carbapenem reported: 22 of 387 patients (6%) in Nairobi, 2 of 190 patients (1%) in Eldoret, and 8 of 184 patients (4%) in Mombasa. Stop dates or review dates were not indicated for 106 of 390 patients (27%) in Nairobi, 75 of 190 patients (40%) in Eldoret, and 113 of 184 patients (72%) in Mombasa receiving antibiotics. Of 761 antibiotic prescriptions, 45% had a least 1 missed dose. Culture and antibiotic susceptibility tests were limited to 50 of 246 patients (20%) in Nairobi, 17 of 124 patients (14%) in Eldoret, and 23 of 119 patients (19%) in Mombasa who received antibiotics. The largest hospital had an administratively recognized antimicrobial stewardship committee. Conclusions: The prevalence of antibiotic use found by our study was 46%, generally lower than the rates reported in 3 similar studies from other African countries, which ranged from 56% to 65%. However, these survey findings indicate that ample opportunities exist for improving antimicrobial stewardship efforts in Kenya considering the high usage of empiric therapy and low microbiologic diagnostic utilization.
Background: Ceftolozane-tazobactam (C/T) and ceftazidime-avibactam (C/A) are new β-lactam/β-lactamase combination antibiotics that were approved by the FDA in 2014 and 2015, respectively, to treat complicated intra-abdominal and urinary tract infections. They are commonly used to treat multidrug-resistant Pseudomonas aeruginosa (MDRPA) and carbapenem-resistant Enterobacteriaceae (CRE) infections at any site. Both medications are also often used as salvage therapy when empiric therapy has failed or when the infectious organism tests resistant to all other available antibiotics. The purpose of this review is to present the clinical experience and reported clinical success rates of C/T and C/A. Methods: PubMed, EMBASE, and Google Scholar were searched from January 1, 2013, through October 1, 2019, for publications detailing clinical experience with C/T and C/A in patients with CRE and MDRPA infections. Included study designs were extended cases series and clinical observational studies. Information on infection type, bacterial agent, salvage therapy uses, clinical success, and resistance development during treatment were abstracted. Meta-regression analysis was used to determine the pooled effectiveness of C/T and C/A among included studies. Results: The literature search returned 1,645 publications. After exclusion criteria were applied, 16 publications representing 769 patients were retained. The study population was mostly male (pooled average, 62%). The major comorbidities represented in the pooled population were solid organ transplantation (20.0%), kidney disease (19.5%), cardiovascular disease (15.3%), and diabetes (15.3%). Pneumonia was the predominant infection type (41.4%) and MDRPA was the pathogen most frequently evaluated (57.7%). The pooled clinical success rate was 70.2% (95% CI, 64.5%–75.3%). Also, 10 studies explicitly evaluated C/A or C/T as salvage therapy. The pooled clinical success rate for salvage therapy studies was 75.2% (95% CI, 69.7%–80.0%). Development of resistance to C/T or C/A during or after treatment was reported for 2.0% of the population. Conclusion: Overall, these medications have a high clinical success rate in patients with severe and complicated infections and limited treatment options. Pooled clinical success rates were high (70.2%) and the medications were particularly effective as salvage therapy. Resistance rates were low, although this could have been biased by the small percentage of studies that reported on this outcome. More longitudinal studies comparing the effectiveness of C/T and C/A against other antibiotic regimens are needed.
Background: Infections caused by Acinetobacter spp are often healthcare acquired, difficult to treat, and associated with high mortality. Extensively drug-resistant (XDR) Acinetobacter are nonsusceptible to at least 1 agent in all but 2 or fewer antimicrobial classes. Epidemiologic and outcome data for XDR Acinetobacter are limited and have largely been reported outside the United States. This national cohort study describes epidemiology, clinical characteristics, and outcomes for patients with XDR Acinetobacter in VA health care. Methods: This was a retrospective cohort study including microbiology and clinical data from all patients hospitalized between 2012 and 2018 at any VA medical center who had cultures that grew XDR Acinetobacter spp. Performance and reporting of bacterial speciation and antibiotic susceptibility testing were performed by each VA laboratory according to their protocol. Descriptive statistics were used to summarize data. Results: Of 11,541 unique patients with 15,358 cultures that grew Acinetobacter spp during the study period, 410 (3.6%) patients had 670 (4.4%) cultures that grew XDR Acinetobacter. Mean age was 68 years (SD, 12.2 years) and the median Charlson comorbidity index was 3 (IQR, 1–5). The greatest proportion of isolates were from the respiratory tract (n = 235, 35%) followed by urine (n = 184, 28%). The South had the greatest proportion of patients with XDR Acinetobacter (n = 162, 40%); almost all patients were seen at urban VA medical centers (n = 406, 99%). Most patients (n = 335, 82%) had had antibiotic exposure in the prior 90 days, most commonly vancomycin (n = 238, 65%) and third- or fourth-generation cephalosporins (n = 155, 38%). Most patients (n = 334, 81%) also had a hospital or long-term care admission in the prior 90 days. Fig. 1 shows antibiotic susceptibilities of XDR Acinetobacter isolates; polymyxins, tigecycline, and minocycline demonstrated the highest susceptibility. In-hospital mortality occurred in 90 patients (22%), 30-day mortality in 97 patients (24%), and 1-year mortality in 198 patients (48%). Of 93 patients, 23% were readmitted to the hospital within 90 days. Conclusions: Providers should maintain a heightened suspicion for infection with XDR Acinetobacter spp in older patients seen at urban medical centers who have had recent healthcare and antibiotic exposures, particularly if they have respiratory or urinary tract infections. Isolation of XDR Acinetobacter is associated with high in-hospital and 30-day mortality. New antibiotics targeting MDR gram-negative bacteria generally lack activity against Acinetobacter, leaving polymyxins, tigecycline, and minocycline as the only limited treatment options. Therefore, novel antibiotics for XDR Acinetobacter are urgently needed.
Background: Carbapenem-resistant Enterobacteriaceae (CRE) are gram-negative bacteria resistant to at least 1 carbapenem and are associated with high mortality (50%). Carbapenemase-producing CRE (CP-CRE) are particularly serious because they are more likely to transmit carbapenem resistance genes to other gram-negative bacteria and they are resistant to all carbapenem antibiotics. Few studies have evaluated risk factors associated with CP-CRE colonization. The goal of this study was to determine the risk factors associated with CP-CRE colonization in a cohort of US veterans. Methods: We conducted a retrospective cohort study of patients seen at VA medical centers between 2013 and 2018 who had positive cultures for CRE from any site, defined by resistance to at least 1 of the following carbapenems: imipenem, meropenem, doripenem, or ertapenem. CP-CRE was defined via antibiotic sensitivity data that coded the culture as being ‘carbapenemase producing,’ being ‘Hodge test positive,’ or ‘KPC producing.’ Only the first positive culture for CRE was included. Patient demographics (year of culture, age, sex, race, major comorbidities, infectious organism, culture site, inpatient status, and CP-CRE status) and facility demographics (rurality, geographic region, and facility complexity) were collected. Bivariate analysis and multiple logistic regression were performed to determine variables associated with CP-CRE versus non–CP-CRE. Results: In total, 3,322 patients were identified with a positive CRE culture: 546 (16.4%) with CP-CRE and 2,776 (83.63%) with non–CP-CRE. Most patients were men (95%) and were older (mean age, 71; SD, 12.5) and were diagnosed at a high-complexity VA medical center (65%). Most of the cultures were urine (63%), followed by sputum (13%), and blood (7%). Most were from inpatients (46%), followed by outpatients (42%), and long-term care facilities (12%). Multivariable analysis showed the following variables to be associated with CP-CRE positive cultures: congestive heart failure (P = .0136), African American (P = .0760), Klebsiella spp (P < .0001), GI cancers (P = .0087), culture collected in 2017 (P = .0004), and culture collected in 2018 (P < .0001). There were also significant differences CP-CRE frequencies by geographic region (P < .001). Discussion: CP-CRE diagnoses are relatively rare; however, the serious complications associated make them important infections to investigate. In our analysis, we found that congestive heart failure and gastric cancer were comorbidities strongly associated with CP-CRE. In 2017, the VA formalized their CP-CRE definition, which led to more accurate reporting. Conclusions: After the guideline was implemented, CP-CRE detection dramatically increased in noncontinental US facilities. More work should be done in the future to determine the different risk factors between non–CP-CRE and CP-CRE infections.
Although infections caused by Acinetobacter baumannii are often healthcare-acquired, difficult to treat, and associated with high mortality, epidemiologic data for this organism are limited. We describe the epidemiology, clinical characteristics, and outcomes for patients with extensively drug-resistant Acinetobacter baumannii (XDRAB).
Retrospective cohort study
Department of Veterans’ Affairs Medical Centers (VAMCs)
Patients with XDRAB cultures (defined as nonsusceptible to at least 1 agent in all but 2 or fewer classes) at VAMCs between 2012 and 2018.
Microbiology and clinical data was extracted from national VA datasets. We used descriptive statistics to summarize patient characteristics and outcomes and bivariate analyses to compare outcomes by culture source.
Among 11,546 patients with 15,364 A. baumannii cultures, 408 (3.5%) patients had 667 (4.3%) XDRAB cultures. Patients with XDRAB were older (mean age, 68 years; SD, 12.2) with median Charlson index 3 (interquartile range, 1–5). Respiratory specimens (n = 244, 36.6%) and urine samples (n = 187, 28%) were the most frequent sources; the greatest proportion of patients were from the South (n = 162, 39.7%). Most patients had had antibiotic exposures (n = 362, 88.7%) and hospital or long-term care admissions (n = 331, 81%) in the prior 90 days. Polymyxins, tigecycline, and minocycline demonstrated the highest susceptibility. Also, 30-day mortality (n = 96, 23.5%) and 1-year mortality (n = 199, 48.8%) were high, with significantly higher mortality in patients with blood cultures.
The proportion of Acinetobacter baumannii in the VA that was XDR was low, but treatment options are extremely limited and clinical outcomes were poor. Prevention of healthcare-associated XDRAB infection should remain a priority, and novel antibiotics for XDRAB treatment are urgently needed.