Carbapenem-resistant Acinetobacter baumannii complex in the United States - an epidemiological and molecular description of isolates collected through the Emerging Infections Program, 2019

BACKGROUND

Understanding the epidemiology of carbapenem-resistant A. baumannii complex (CRAB) and the patients impacted is an important step towards informing better infection prevention and control practices and improving public health response.

METHODS

Active, population-based surveillance was conducted for CRAB in 9 U.S. sites from January 1-December 31, 2019. Medical records were reviewed, isolates were collected and characterized including antimicrobial susceptibility testing and whole genome sequencing.

RESULTS

Among 136 incident cases in 2019, 66 isolates were collected and characterized; 56.5% were from cases who were male, 54.5% were from persons of Black or African American race with non-Hispanic ethnicity, and the median age was 63.5 years. Most isolates, 77.2%, were isolated from urine, and 50.0% were collected in the outpatient setting; 72.7% of isolates harbored an acquired carbapenemase gene (aCP), predominantly blaOXA-23 or blaOXA-24/40; however, an isolate with blaNDM was identified. The antimicrobial agent with the most in vitro activity was cefiderocol (96.9% of isolates were susceptible).

CONCLUSIONS

Our surveillance found that CRAB isolates in the U.S. commonly harbor an aCP, have an antimicrobial susceptibility profile that is defined as difficult-to-treat resistance, and epidemiologically are similar regardless of the presence of an aCP.

Trends in Incidence of Carbapenem-Resistant Enterobacterales in 7 US Sites, 2016─2020

Background

We described changes in 2016─2020 carbapenem-resistant Enterobacterales (CRE) incidence rates in 7 US sites that conduct population-based CRE surveillance.

Methods

An incident CRE case was defined as the first isolation of Escherichia coli, Klebsiella spp., or Enterobacter spp. resistant to ≥1 carbapenem from a sterile site or urine in a surveillance area resident in a 30-day period. We reviewed medical records and classified cases as hospital-onset (HO), healthcare-associated community-onset (HACO), or community-associated (CA) CRE based on healthcare exposures and location of disease onset. We calculated incidence rates using census data. We used Poisson mixed effects regression models to perform 2016─2020 trend analyses, adjusting for sex, race/ethnicity, and age. We compared adjusted incidence rates between 2016 and subsequent years using incidence rate ratios (RRs) and 95% confidence intervals (CIs).

Results

Of 4996 CRE cases, 62% were HACO, 21% CA, and 14% HO. The crude CRE incidence rate per 100 000 was 7.51 in 2016 and 6.08 in 2020 and was highest for HACO, followed by CA and HO. From 2016 to 2020, the adjusted overall CRE incidence rate decreased by 24% (RR, 0.76 [95% CI, .70-.83]). Significant decreases in incidence rates in 2020 were seen for HACO (RR, 0.75 [95% CI, .67-.84]) and CA (0.75 [.61-.92]) but not for HO CRE.

Conclusions

Adjusted CRE incidence rates declined from 2016 to 2020, but changes over time varied by epidemiologic class. Continued surveillance and effective control strategies are needed to prevent CRE in all settings.

Epidemiology of Pulmonary and Extrapulmonary Nontuberculous Mycobacteria Infections at 4 US Emerging Infections Program Sites: A 6-Month Pilot

BACKGROUND

Nontuberculous mycobacteria (NTM) cause pulmonary (PNTM) and extrapulmonary (ENTM) disease. Infections are difficult to diagnose and treat, and exposures occur in healthcare and community settings. In the United States, NTM epidemiology has been described largely through analyses of microbiology data from health departments, electronic health records, and administrative data. We describe findings from a multisite pilot of active, laboratory- and population-based NTM surveillance.

METHODS

The Centers for Disease Control and Prevention's Emerging Infections Program conducted NTM surveillance at 4 sites (Colorado, 5 counties; Minnesota, 2 counties; New York, 2 counties; and Oregon, 3 counties [PNTM] and statewide [ENTM]) from 1 October 2019 through 31 March 2020. PNTM cases were defined using published microbiologic criteria. ENTM cases required NTM isolation from a nonpulmonary specimen, excluding stool and rectal swabs. Patient data were collected via medical record review.

RESULTS

Overall, 299 NTM cases were reported (PNTM: 231, 77%); Mycobacterium avium complex was the most common species group. Annualized prevalence was 7.5/100 000 population (PNTM: 6.1/100 000; ENTM: 1.4/100 000). Most patients had signs or symptoms in the 14 days before positive specimen collection (ENTM: 62, 91.2%; PNTM: 201, 87.0%). Of PNTM cases, 145 (62.8%) were female and 168 (72.7%) had underlying chronic lung disease. Among ENTM cases, 29 (42.6%) were female, 21 (30.9%) did not have documented underlying conditions, and 26 (38.2%) had infection at the site of a medical device or procedure.

CONCLUSIONS

Active, population-based NTM surveillance will provide data for monitoring the burden of disease and characterize affected populations to inform interventions.

Carbapenem-Resistant enterobacterales in individuals with and without health care risk factors -Emerging infections program, United States, 2012-2015

BACKGROUND

Carbapenem-resistant Enterobacterales (CRE) are usually healthcare-associated but are also emerging in the community.

METHODS

Active, population-based surveillance was conducted to identify case-patients with cultures positive for Enterobacterales not susceptible to a carbapenem (excluding ertapenem) and resistant to all third-generation cephalosporins tested at 8 US sites from January 2012 to December 2015. Medical records were used to classify cases as health care-associated, or as community-associated (CA) if a patient had no known health care risk factors and a culture was collected <3 days after hospital admission. Enterobacterales isolates from selected cases were submitted to CDC for whole genome sequencing.

RESULTS

We identified 1499 CRE cases in 1194 case-patients; 149 cases (10%) in 139 case-patients were CA. The incidence of CRE cases per 100,000 population was 2.96 (95% CI: 2.81, 3.11) overall and 0.29 (95% CI: 0.25, 0.35) for CA-CRE. Most CA-CRE cases were in White persons (73%), females (84%) and identified from urine cultures (98%). Among the 12 sequenced CA-CRE isolates, 5 (42%) harbored a carbapenemase gene.

CONCLUSIONS

Ten percent of CRE cases were CA; some isolates from CA-CRE cases harbored carbapenemase genes. Continued CRE surveillance in the community is critical to monitor emergence outside of traditional health care settings.

Extensively Drug-Resistant Carbapenemase-Producing Pseudomonas aeruginosa and Medical Tourism from the United States to Mexico, 2018-2019

Carbapenem-resistant Pseudomonas aeruginosa (CRPA) producing the Verona integron‒encoded metallo-β-lactamase (VIM) are highly antimicrobial drug-resistant pathogens that are uncommon in the United States. We investigated the source of VIM-CRPA among US medical tourists who underwent bariatric surgery in Tijuana, Mexico. Cases were defined as isolation of VIM-CRPA or CRPA from a patient who had an elective invasive medical procedure in Mexico during January 2018‒December 2019 and within 45 days before specimen collection. Whole-genome sequencing of isolates was performed. Thirty-eight case-patients were identified in 18 states; 31 were operated on by surgeon 1, most frequently at facility A (27/31 patients). Whole-genome sequencing identified isolates linked to surgeon 1 were closely related and distinct from isolates linked to other surgeons in Tijuana. Facility A closed in March 2019. US patients and providers should acknowledge the risk for colonization or infection after medical tourism with highly drug-resistant pathogens uncommon in the United States.

Compliance with statewide regulations for communication of patients' multidrug-resistant organism and Clostridium difficile status during transitions of care

In 2014, Oregon implemented an interfacility transfer communication law requiring notification of multidrug-resistant organism status on patient transfer. Based on 2015 and 2016 statewide facility surveys, compliance was 77% and 87% for hospitals, and 67% and 68% for skilled nursing facilities. Methods for complying with the rule were heterogeneous, and fewer than half of all facilities surveyed reported use of a standardized interfacility transfer communication form to assess a patient's multidrug-resistant organism status on transfer.

Carbapenem-Resistant Pseudomonas aeruginosa at US Emerging Infections Program Sites, 2015

Pseudomonas aeruginosa is intrinsically resistant to many antimicrobial drugs, making carbapenems crucial in clinical management. During July–October 2015 in the United States, we piloted laboratory-based surveillance for carbapenem-resistant P. aeruginosa (CRPA) at sentinel facilities in Georgia, New Mexico, Oregon, and Tennessee, and population-based surveillance in Monroe County, NY. An incident case was the first P. aeruginosa isolate resistant to antipseudomonal carbapenems from a patient in a 30-day period from any source except the nares, rectum or perirectal area, or feces. We found 294 incident cases among 274 patients. Cases were most commonly identified from respiratory sites (120/294; 40.8%) and urine (111/294; 37.8%); most (223/280; 79.6%) occurred in patients with healthcare facility inpatient stays in the prior year. Genes encoding carbapenemases were identified in 3 (2.3%) of 129 isolates tested. The burden of CRPA was high at facilities under surveillance, but carbapenemase-producing CRPA were rare.

Outbreak of Nontuberculous Mycobacteria Joint Prosthesis Infections, Oregon, USA, 2010-2016

We investigated a cluster of Mycobacterium fortuitum and M. goodii prosthetic joint surgical site infections occurring during 2010–2014. Cases were defined as culture-positive nontuberculous mycobacteria surgical site infections that had occurred within 1 year of joint replacement surgery performed on or after October 1, 2010. We identified 9 cases by case finding, chart review, interviews, surgical observations, matched case–control study, pulsed-field gel electrophoresis of isolates, and environmental investigation; 6 cases were diagnosed >90 days after surgery. Cases were associated with a surgical instrument vendor representative being in the operating room during surgery; other potential sources were ruled out. A tenth case occurred during 2016. This cluster of infections associated with a vendor reinforces that all personnel entering the operating suite should follow infection control guidelines; samples for mycobacterial culture should be collected early; and postoperative surveillance for <90 days can miss surgical site infections caused by slow-growing organisms requiring specialized cultures, like mycobacteria.

486. Epidemiology of Carbapenem-Resistant Pseudomonas aeruginosa Identified through the Emerging Infections Program (EIP), United States, 2016–2018

Background

Pseudomonas aeruginosa is intrinsically resistant to many commonly used antimicrobials, and carbapenems are often required to treat infections. We describe the crude incidence, epidemiology, and molecular characteristics of carbapenem-resistant P. aeruginosa (CRPA) in the EIP catchment area.

Methods

From August 1, 2016 through July 31, 2018, we conducted laboratory- and population-based surveillance for CRPA in selected areas in eight sites. We defined a case as the first isolate of P. aeruginosa resistant to imipenem, meropenem, or doripenem from the lower respiratory tract, urine, wounds, or normally sterile sites identified from a resident of the EIP catchment area in a 30-day period. Patient charts were reviewed. Analysis excluded cystic fibrosis patients. A random sample of isolates was collected. Real-time PCR to detect carbapenemase genes and whole-genome sequencing are in progress.

Results

We identified 4,209 cases in 3373 patients. The annual incidence was 14.50 (95% CI, 14.07–14.94) per 100,000 persons and varied among sites from 4.89 in OR to 25.21 in NY. The median age of patients was 66 years (range: < 1–101), 42.1% were female, and nearly all (97.5%) had an underlying condition. Most cases were identified from urine (42.8%) and lower respiratory tract (35.7%) cultures. Nearly all (93.3%) occurred in patients with inpatient healthcare facility stay, surgery, chronic dialysis, or indwelling devices in the prior year; death occurred in 7.2%. Among 937 isolates tested, 847 (90.4%) underwent PCR; six (0.7%) harbored a carbapenemase, from four sites (CO, MD, NY, and OR): bla_VIM (3), bla_KPC (2), and bla_IMP (1). Of 612 (65.3%) isolates sequenced, the most common ST types were ST235 (9.2%) and ST298 (4.9%).

Conclusion

Carbapenemases were rarely the cause of carbapenem resistance but were found at EIP sites with high and low CRPA incidence. The emergence of mobile carbapenemases in P. aeruginosa has the potential to increase the incidence of CRPA. Increased detection and early response to carbapenemase-producing CRPA is key to prevent further emergence.

Disclosures

All authors: No reported disclosures.

2340. Diagnostic Stewardship: Survey of Urine Culturing and C. difficile Testing Practices Amongst Oregon Microbiology Labs

Background

Testing for urinary tract infection (UTI) and Clostridiodes difficile infection (CDI) poses diagnostic and antimicrobial stewardship challenges. Both diagnoses hinge on local microbiology laboratory algorithms. For UTI testing, the definition of “abnormal” urinalysis and the use of reflex urine cultures, both of which alter the frequency of bacteriuria detection, likely differs between laboratories. For CDI, pretest probability, choice and sequence of diagnostic tests are likely variable and impact the chances of accurate diagnosis.

Methods

To understand laboratory practices and determine variations in local testing algorithms, we deployed a self-administered survey to microbiology laboratories serving Oregon healthcare facilities via SurveyMonkey in September 2018. Responses were collected through April 2019. We analyzed a subset of questions focused on UTI and CDI diagnosis.

Results

Of 51 surveyed laboratories, response rate was 86% (n = 44). 91% of respondents (n = 40) process bacterial cultures. 47.5% (n = 19) primarily perform urine culture when ordered, whereas the remainder primarily perform cultures in a reflex algorithm when ordered (n = 12; 30%) or a reflex algorithm automatically (n = 9; 22.5%) (Figure 1). The definition of an abnormal urinalysis varied widely (Figure 2). 15% (n = 6) of laboratories reported considering changes to their workflow; two cited a goal of reducing unnecessary testing. Of the 32 laboratories that perform in-house C. difficile testing, the assays and sequence in which they were implemented in testing algorithms varied substantially (Figure 3) and most commonly included NAAT testing. Seven (21.8%) laboratories reported recently changed practices; these changes did not favor any particular algorithm. 84.2% (n = 32) reported stool rejection criteria to limit unnecessary testing, but these criteria varied (Figure 4).

Conclusion

Wide variation exists in laboratory workflows for UTI and CDI diagnoses in Oregon, suggesting lack of consensus on optimal practices. Encouragingly, multiple labs described recently implemented or planned interventions to reduce unnecessary testing for both infections. This snapshot will inform statewide education and interventions to optimize testing and help prevent patient and population harm.

Disclosures

All authors: No reported disclosures.

Carbapenem-Nonsusceptible Acinetobacter baumannii, 8 US Metropolitan Areas, 2012-2015

In healthcare settings, Acinetobacter spp. bacteria commonly demonstrate antimicrobial resistance, making them a major treatment challenge. Nearly half of Acinetobacter organisms from clinical cultures in the United States are nonsusceptible to carbapenem antimicrobial drugs. During 2012–2015, we conducted laboratory- and population-based surveillance in selected metropolitan areas in Colorado, Georgia, Maryland, Minnesota, New Mexico, New York, Oregon, and Tennessee to determine the incidence of carbapenem-nonsusceptible A. baumannii cultured from urine or normally sterile sites and to describe the demographic and clinical characteristics of patients and cases. We identified 621 cases in 537 patients; crude annual incidence was 1.2 cases/100,000 persons. Among 598 cases for which complete data were available, 528 (88.3%) occurred among patients with exposure to a healthcare facility during the preceding year; 506 (84.6%) patients had an indwelling device. Although incidence was lower than for other healthcare-associated pathogens, cases were associated with substantial illness and death.

1761. Effect of Carbapenem-Resistant Enterobacteriaceae (CRE) Surveillance Case Definition Change on CRE Epidemiology—Selected US Sites, 2015–2016

Background

Carbapenem-resistant Enterobacteriacae (CRE) are an urgent US public health threat. CDC reported CRE incidence to be 2.93/100,000 population in 2012–2013 in selected sites but changed the CRE surveillance case definition in 2016 to improve sensitivity for detecting carbapenemase-producing (CP) CRE. We describe CRE epidemiology before and after the change.

Methods

Eight CDC Emerging Infections Program sites (CO, GA, MD, MN, NM, NY, OR, TN) conducted active, population-based CRE surveillance in selected counties. A case was defined as having an isolate of E. coli, Enterobacter, or Klebsiella meeting a susceptibility phenotype (figure) at a clinical laboratory from urine or a normally sterile body site in a surveillance area resident in a 30-day period. We collected data from medical records and defined cases as community-associated (CA) if no healthcare risk factors were documented. A convenience sample of isolates were tested for carbapenemase genes at CDC by real-time PCR. We calculated incidence rates (per 100,000 population) by using US Census data. Case epidemiology and the proportion of CP-CRE isolates in 2015 versus 2016 were compared.

Results

In total, 442 incident CRE cases were reported in 2015, and 1,149 cases were reported in 2016. Most isolates were cultured from urine: 87% in 2015 and 92% in 2016 (P < .001). The crude overall pooled mean incidence in 2015 was 2.9 (range by site: 0.45–7.19) and in 2016 was 7.48 (range: 3.13–15.95). The most common CRE genus was Klebsiella (51%) in 2015, and in 2016 was Enterobacter (41%, P < 0.001). Of the subset of CRE isolates tested at CDC, 109/227 (48%) were CP-CRE in 2015 and 109/551 (20%) were CP-CRE in 2016. In 2015, 52/442 (12%) of cases were CA CRE, and in 2016, 267/1,149 (23%) were CA CRE (P < 0.001). In 2016, 3/111 (2.7%) of CA CRE isolates tested were CP-CRE.

Conclusion

A large increase in reported CRE incidence was observed after the change in the case definition. The new case definition includes a substantially larger number of Enterobacter cases. A decrease in CP-CRE prevalence appears to be driven by an increase in non-CP-CRE cases. Although CP-CRE in the community still appear to be rare, a substantial proportion of phenotypic CRE appear to be CA, and CDC is undertaking efforts to further investigate CA CRE, including CP-CRE.

Disclosures

G. Dumyati, Seres: Scientific Advisor, Consulting fee.

1162. Epidemiology of Carbapenem-Resistant Pseudomonas aeruginosa Identified Through the Emerging Infections Program (EIP), United States, 2016–2017

Background

Pseudomonas aeruginosa is intrinsically resistant to many commonly used antimicrobials and carbapenems are often required to treat infections. We describe the epidemiology and crude incidence of carbapenem-resistant P. aeruginosa(CRPA) in the EIP catchment area.

Methods

From August 1, 2016 through July 31, 2017, we conducted laboratory- and population-based surveillance for CRPA in selected metropolitan areas in Colorado, Georgia, Maryland, Minnesota, New Mexico, New York, Oregon, and Tennessee. We defined an incident case as the first isolate of P. aeruginosa-resistant to imipenem, meropenem, or doripenem from the lower respiratory tract, urine, wounds, or normally sterile sites identified from a resident of the EIP catchment area in a 30-day period. Patient charts were reviewed. A random sample of isolates was screened at CDC for carbapenemases using the modified carbapenem inactivation method (mCIM) and real-time PCR.

Results

During the 12-month period, we identified 3,042 incident cases among 2,154 patients. The crude incidence rate was 21.2 (95% CI, 20.4–21.9) per 100,000 persons and varied by site (range: 7.7 in Oregon to 31.1 in Maryland). The median age of patients was 64 years (range: <1–101) and 41.2% were female. Nearly all (97.1%) had at least one underlying condition and 10.2% had cystic fibrosis (CF); 17.8% of cases were from CF patients. For most cases, isolates were from the lower respiratory tract (49.2%) or urine (35.3%) and occurred in patients with recent hospitalization (87.2%) or indwelling devices (70.3%); 8.7% died. At the clinical laboratory, 84.7% of isolates were susceptible to an aminoglycoside and 66.4% to ceftazidime or cefepime. Among the 391 isolates tested, nine (2.3%) were mCIM-positive; one had a carbapenemase detected by PCR (bla_VIM-4).

Conclusion

The burden of CRPA varied by EIP site. Most cases occurred in persons with healthcare exposures and underlying conditions. The majority of isolates were susceptible to at least one first-line antimicrobial. Carbapenemase producers were rare; a more specific phenotypic definition would greatly facilitate surveillance for these isolates.

Disclosures

All authors: No reported disclosures.

Extrapulmonary Nontuberculous Mycobacterial Disease Surveillance - Oregon, 2014-2016

Nontuberculous mycobacteria (NTM), ubiquitous in soil and water, usually infect immunocompromised persons. However, even healthy persons are susceptible to infection through percutaneous inoculation. Although 77% of NTM diseases manifest as primarily pulmonary illnesses (1), NTM also infect skin, bones, joints, the lymphatic system, and soft tissue. NTM infections can have incubation periods that exceed 5 years (2), often require prolonged treatment, and can lead to sepsis and death. Extrapulmonary NTM outbreaks have been reported in association with contaminated surgical gentian violet (3), nail salon pedicures (4), and tattoos received at tattoo parlors (5), although few surveillance data have been available for estimating the public health burden of NTM.* On January 1, 2014, the Oregon Health Authority designated extrapulmonary NTM disease a reportable condition. To characterize extrapulmonary NTM infection, estimate resources required for surveillance, and assess the usefulness of surveillance in outbreak detection and investigation, 2014–2016 extrapulmonary NTM surveillance data were reviewed, and interviews with stakeholders were conducted. During 2014–2016, 134 extrapulmonary NTM cases (11 per 1 million persons per year) were reported in Oregon. The age distribution was bimodal, with highest incidence among persons aged <10 years (20 per 1 million persons per year) and persons aged 60–69 years (18 per 1 million persons per year). The most frequently reported predisposing factors (occurring within 14–70 days of symptom onset) were soil exposure (41/98; 42%), immunocompromised condition (42/124; 34%), and surgery (32/120; 27%). Overall, 43 (33%) patients were hospitalized, 18 (15%) developed sepsis, and one (0.7%) died. Surveillance detected or helped to control two outbreaks at low cost. Jurisdictions interested in implementing extrapulmonary NTM surveillance can use the Council of State and Territorial Epidemiologists (CSTE) standardized case definition (6) for extrapulmonary NTM reporting or investigative guidelines maintained by the Oregon Health Authority (7).

Wide Range of Carbapenem-resistant Enterobacteriaceae Incidence and Trends in Emerging Infections Program Surveillance, 2012–2015

Background

Carbapenem-resistant Enterobacteriaceae (CRE) are an urgent threat in the United States because of high morbidity and mortality, few treatment options, and potential for rapid spread among patients. To assess for changes in CRE epidemiology and risk among populations, we analyzed CDC Emerging Infections Program (EIP) 2012–2015 surveillance data for CRE.

Methods

Active, population-based CRE surveillance was initiated in January 2012 at 3 EIP sites (GA, MN, OR) and expanded to 5 additional sites (CO, MD, NM, New York, TN) by 2014. An incident case was the first Escherichia coli, Enterobacter, or Klebsiella isolate (non-susceptible to at least one carbapenem and resistant to all third-generation cephalosporins tested) collected from urine or a normally sterile body site from a patient during a 30-day period. Data were collected from patients’ medical records. Cases were hospital-onset (HO) or long-term care facility (LTCF) onset if patients were in the respective facility ≥3 days prior to culture or at the time of culture; and community-onset (CO) otherwise. We calculated incidence rates based on census data for EIP sites and described by type of infection onset.

Results

A total of 1,582 incident CRE cases were reported in 2012–2015. Most cases (88%) were identified through urine cultures; 946 (60%) were female, and median age was 66 years (interquartile range: 55–77). The median incidence by site was 2.95 per 100,000 population (range: 0.35–8.98). Among the three sites with four full years of data, a different trend was seen in each (Figure). Trends in GA and MN were statistically significant, and no significant trend was seen in OR. Overall, 480 cases (30%) were HO, 524 (33%) were LTCF onset, and 578 (37%) were CO. Of CO cases, 308 (53%) had been hospitalized, admitted to a long- term acute care hospital or were a LTCF resident in the prior year.

Conclusion

CRE incidence varied more than 20-fold across surveillance sites, with evidence of continued increases in MN. Measuring impact of programs aimed at reducing CRE transmission in other regions will require obtaining local data to identify cases occurring during and after healthcare facility discharge. Further study of changes in incidence in some settings and areas might offer opportunities to refine and expand effective control strategies.

Disclosures

All authors: No reported disclosures.

Epidemiology of Carbapenem-Resistant Enterobacteriaceae in 7 US Communities, 2012-2013

IMPORTANCE

Carbapenem-resistant Enterobacteriaceae (CRE) are increasingly reported worldwide as a cause of infections with high-mortality rates. Assessment of the US epidemiology of CRE is needed to inform national prevention efforts.

OBJECTIVE

To determine the population-based CRE incidence and describe the characteristics and resistance mechanism associated with isolates from 7 US geographical areas.

DESIGN, SETTING, AND PARTICIPANTS

Population- and laboratory-based active surveillance of CRE conducted among individuals living in 1 of 7 US metropolitan areas in Colorado, Georgia, Maryland, Minnesota, New Mexico, New York, and Oregon. Cases of CRE were defined as carbapenem-nonsusceptible (excluding ertapenem) and extended-spectrum cephalosporin-resistant Escherichia coli, Enterobacter aerogenes, Enterobacter cloacae complex, Klebsiella pneumoniae, or Klebsiella oxytoca that were recovered from sterile-site or urine cultures during 2012-2013. Case records were reviewed and molecular typing for common carbapenemases was performed.

EXPOSURES

Demographics, comorbidities, health care exposures, and culture source and location.

MAIN OUTCOMES AND MEASURES

Population-based CRE incidence, site-specific standardized incidence ratios (adjusted for age and race), and clinical and microbiological characteristics.

RESULTS

Among 599 CRE cases in 481 individuals, 520 (86.8%; 95% CI, 84.1%-89.5%) were isolated from urine and 68 (11.4%; 95% CI, 8.8%-13.9%) from blood. The median age was 66 years (95% CI, 62.1-65.4 years) and 284 (59.0%; 95% CI, 54.6%-63.5%) were female. The overall annual CRE incidence rate per 100<000 population was 2.93 (95% CI, 2.65-3.23). The CRE standardized incidence ratio was significantly higher than predicted for the sites in Georgia (1.65 [95% CI, 1.20-2.25]; P < .001), Maryland (1.44 [95% CI, 1.06-1.96]; P = .001), and New York (1.42 [95% CI, 1.05-1.92]; P = .048), and significantly lower than predicted for the sites in Colorado (0.53 [95% CI, 0.39-0.71]; P < .001), New Mexico (0.41 [95% CI, 0.30-0.55]; P = .01), and Oregon (0.28 [95% CI, 0.21-0.38]; P < .001). Most cases occurred in individuals with prior hospitalizations (399/531 [75.1%; 95% CI, 71.4%-78.8%]) or indwelling devices (382/525 [72.8%; 95% CI, 68.9%-76.6%]); 180 of 322 (55.9%; 95% CI, 50.0%-60.8%) admitted cases resulted in a discharge to a long-term care setting. Death occurred in 51 (9.0%; 95% CI, 6.6%-11.4%) cases, including in 25 of 91 cases (27.5%; 95% CI, 18.1%-36.8%) with CRE isolated from normally sterile sites. Of 188 isolates tested, 90 (47.9%; 95% CI, 40.6%-55.1%) produced a carbapenemase.

CONCLUSIONS AND RELEVANCE

In this population- and laboratory-based active surveillance system in 7 states, the incidence of CRE was 2.93 per 100<000 population. Most CRE cases were isolated from a urine source, and were associated with high prevalence of prior hospitalizations or indwelling devices, and discharge to long-term care settings.

Distinguishing tuberculosis from nontuberculous mycobacteria lung disease, Oregon, USA

To determine whether tuberculosis (TB) and nontuberculous mycobacteria (NTM) infection patients could be distinguished from one another with limited information, we compared pulmonary TB and NTM patients during 2005–2006. Our finding that age, birthplace, and presence of chronic obstructive pulmonary disease could differentiate TB and NTM disease could assist tuberculosis control efforts.

Isolation of non-tuberculous mycobacteria from the sputum of patients with active tuberculosis

We looked for non-tuberculous mycobacteria (NTM) in the sputum of patients diagnosed with pulmonary tuberculosis (TB) in Oregon in 2005-2006 (n = 141). Twenty (14%) patients had NTM isolated from sputum during TB treatment. Compared to those without NTM, TB patients with NTM were more likely to have cavitary disease (RR 2.7, 95%CI 1.2-6.0) and were more likely to be born in the United States (RR 2.4, 95%CI 1.1-5.3). Further study is needed to determine the clinical significance of simultaneous isolation of NTM and TB.

Nontuberculous mycobacterial disease prevalence and risk factors: a changing epidemiology

BACKGROUND

Nontuberculous mycobacteria (NTM) are important human pathogens, yet little is known about disease prevalence in the United States. Reports suggest prevalence has increased, particularly in women, but population-based data to substantiate this are lacking. We sought to estimate NTM disease prevalence in Oregon, and describe disease by site, species, and patient demographic characteristics.

METHODS

We contacted laboratories that performed mycobacterial cultures on Oregon residents in 2005-2006. For each isolate, we obtained source, collection date, species, and patient demographics. We used the microbiologic component of the American Thoracic Society/Infectious Diseases Society of America's pulmonary NTM disease criteria to define cases of pulmonary NTM, and patients with isolates from a normally sterile site were classified as having extrapulmonary disease.

RESULTS

We identified 933 patients with > or =1 NTM isolate. Of these, 527 (56%) met the case definition (annualized prevalence, 7.2 cases per 100,000 persons). Pulmonary cases predominated (5.6 cases per 100,000 persons), followed by skin/soft-tissue cases (0.9 cases per 100,000 persons). Mycobacterium avium complex was the most common species identified in pulmonary cases (4.7 cases per 100,000 persons). Pulmonary disease prevalence was significantly higher in women (6.4 cases per 100,000 persons) than men (4.7 cases per 100,000 persons) and was highest in persons aged >50 years (15.5 cases per 100,000 persons).

CONCLUSIONS

NTM are frequently isolated from Oregon residents; more than one-half of all isolates likely represent true disease. Pulmonary NTM is most common among elderly women, and M. avium causes most disease. Future efforts to monitor disease trends should be undertaken, and efforts made to validate the use of the ATS/IDSA microbiologic criteria alone to predict pulmonary NTM disease.

Aggregated antibiograms and monitoring of drug-resistant Streptococcus pneumoniae

Community-specific antimicrobial susceptibility data may help monitor trends among drug-resistant Streptococcus pneumoniae and guide empiric therapy. Because active, population-based surveillance for invasive pneumococcal disease is accurate but resource intensive, we compared the proportion of penicillin-nonsusceptible isolates obtained from existing antibiograms, a less expensive system, to that obtained from 1 year of active surveillance for Georgia, Tennessee, California, Minnesota, Oregon, Maryland, Connecticut, and New York. For all sites, proportions of penicillin-nonsusceptible isolates from antibiograms were within 10 percentage points (median 3.65) of those from invasive-only isolates obtained through active surveillance. Only 23% of antibiograms distinguished between isolates intermediate and resistant to penicillin; 63% and 57% included susceptibility results for erythromycin and extended-spectrum cephalosporins, respectively. Aggregating existing hospital antibiograms is a simple and relatively accurate way to estimate local prevalence of penicillin-nonsusceptible pneumococcus; however, antibiograms offer limited data on isolates with intermediate and high-level penicillin resistance and isolates resistant to other agents.

Life History Patterns of Discorsopagurus schmitti, a Hermit Crab Inhabiting Polychaete Tubes

Discorsopagurus schmitti is a hermit crab that inhabits empty polychaete tubes in the North Pacific. Here we describe some aspects of its life history (relative growth, population structure, reproductive biology, and incidence of parasitism) and discuss the relationships among them. Unlike most hermits, the two sexes of this species have similar size distributions. In both sexes, larger body size is accompanied by a higher reproductive output (larger clutch size in females and more intrasex competitive potential in males). The energy the females expend in egg production might be equaled in this species by the energy the males expend in supporting parasites. In fact, the extent of infestation by two rhizocephalans [Peltogaster boschmae and Thilacoplethus (=Thompsonia) reinhardi] is more pronounced in males, especially those in the larger size classes. However, rhizocephalans have little effect on their hosts; growth and secondary sexual characters are not influenced. The only morphological modification is the more frequent loss of the second pleopod. Infected hermits also showed a mock parental behavior, fanning the externae with the pleopods as ovigerous females fan their eggs. Larvae are released in sequential bursts, and hatching occurs exclusively at night, possibly to minimize predation by diurnal fishes. Hatching is also synchronized with neap tides, which might keep the larvae from being flushed out into open waters. In a species whose habitat (sabellarian bioherms) is rare and quite unpredictable, it is beneficial to retain larvae near the parental population.