bluuebunny/crossref_metadata_2025_split huggingface dataset:
405. Serum Antibody Responses Against Carbapenem-Resistant Klebsiella pneumoniae in Infected Patients
Authors: Banerjee Kasturi , Motley Michael , Diago-Navarro Elizabeth , Fries Bettina C 
Published: October 2019

Abstract

Background
Capsular polysaccharide (CPS) of Carbapenem-resistant K. pneumoniae ST258 (CR-Kp) is a potential vaccine target. CPS of these isolates generally falls within 2 homology groups named clade 1 and clade 2. We and others have made antibodies (Abs) that act against clade2 CR-Kp but failed to make therapeutic Abs against clade1 CR-Kp. Previous studies had shown that studying patient’s antibody responses could help in identifying suitable candidates for developing immunotherapies. Thus, we sought to identify potential vaccine candidates by investigating the humoral response CPS in CR-Kp-infected patients.

Methods
24 CR-Kp isolates and corresponding serums were collected from inpatients at Stony Brook Hospital. CPS was isolated and purified by size-exclusion column chromatography from CR-Kp strains 34 (clade 2), 36 (clade 1), and 38 (clade-Other). Anti-CPS Abs in patient’s serum were detected by enzyme-linked immunosorbent assay (ELISA) and bulk Abs from positive serum were purified using an affinity column. These Abs were tested for activity against CR-Kp by serum bactericidal and agglutination assays.

Results
50% of clade2 CR-Kp-infected patients had humoral responses against CPS34. 77% of clade 1-infected patients sera cross-reacted wtih CPS34, but none of them developed Abs against CPS36. Interestingly, 90% of clade1 and 60% of clade 2-infected patients, respectively, showed Abs binding to CPS38. Thus, we selectively purified Anti-CPS Abs from two clade-Other-infected patients and observed that they were cross-reactive with all three CPS. Further, these Anti-CPS Abs agglutinated all tested CR-Kp isolates (34, 36, and 38) when compared with control human IgG (P < 0.005). Additionally, these Anti-CPS Abs promoted killing of clade2 bacteria and inhibited the growth of clade1 bacteria in Ab-mediated serum bactericidal assay. These data elucidate that humoral responses developed in clade-Other CR-Kp-infected patients have therapeutic potential.

Conclusion
With the unavailability of effective antimicrobials for CR-Kp, approaches like developing novel anti-CPS vaccine could serve as an alternate therapy. Our data suggest that developing immunotherapies targeting CPS38 could potentially provide protection across both clade1 and clade2 bacteria in clinical settings.

Disclosures
All authors: No reported disclosures.
428. Lower Incidence Rates of Neisseria gonorrhoeae and Chlamydia trachomatis in Pre- Exposure Prophylaxis Patients Over Fifty Years Old Than in Younger Quartiles.
Authors: Morris-Haris Deborah Gail 
Published: October 2019

Abstract

Background
While Pre-Exposure Prophylaxis (PrEP) has been shown to be effective in preventing the acquisition of HIV, the cost of care is considerable. Public health efforts should be directed to those at highest risk to minimize the cost of a quality-adjusted life-year (QALY).
Given that sexually transmitted illnesses (STIs) increase the risk of acquiring HIV from 5–8 fold, their incidence rates can serve to define populations at highest risk for HIV within the community of men who have sex with men (MSM).

Methods
A retrospective cohort of PrEP patients with STI screening visits in two clinics in Dallas, Texas from January 2016 through April 2019 were reviewed. Three-site genital and extra-genital testing was routinely performed. Categorical variables were compared using Chi-Square. A binomial regression model was used to evaluate the odds of STI acquisition.

Results
201 PrEP patients had 999 screening visits. 17 were in the first quartile, ages (18–24) 35.3% were Black, 70.6% MSM; 105 were in the second quartile, ages (25–37) 23.8% Black, 58.1% MSM; 56 third quartile, ages (38–49) 17.9% Black, 62.5% MSM; 23 patients in the fourth quartile, age ≥50, 8.7% were Black, 47.8% MSM. The younger age group, first quartile contributed 16 person-years (py); the second quartile, 102 py; third quartile, 48 py; fourth quartile, ≥50, 25 py. The incidence rates for Neisseria gonorrhoeae (GC) or Chlamydia trachomatis (CT) from any site were higher in the first quartile, 166/100 py, CI 150–174; second quartile, 92/100 py, CI- 85–96; third quartile, 62/100 py, CI 48–75 than in those in the fourth quartile, ≥50 years old, 44/100 py, CI 27–63. The incidence of any rectal GCor CT in the first quartile, 86/100 py, CI 63–98; second quartile, 53/100 py, CI 43–62; third quartile, 29/100 py, CI 18–43 and those in the fourth quartile, ≥50, 32/100 py, CI 17–52. In a binomial regression model, the odds of acquiring any GC or CT for a PrEP patient ≥50 revealed an adjusted OR of 0.40, CI, 0.20–0.79 (adjusted for race and sexual orientation) P = 0.009 when compared with patients less than 50.

Conclusion
PrEP patients fifty and older have the lowest odds of acquiring STIs. Younger age groups with higher incidences of STIs may represent those with more episodes of condomless sex, at higher risk for HIV.

Disclosures
All authors: No reported disclosures.
429. Ocular gonorrhea infections in New York City, 2006–2017
Authors: Sfeir Maroun M , Johnson Kimberly , Klingler Ellen , Schillinger Julia 
Published: October 2019

Abstract

Background
Ocular gonorrhea infections (OGI) have been rarely reported in United States adults. Unlike other bacterial eye infections which may be treated with topical antibiotics, OGI is typically characterized by purulent conjunctivitis with profuse exudate and requires treatment with systemic antibiotics. Genital gonorrhea infections are increasing nationally and in New York City (NYC). New York State mandates prophylactic antibiotic treatment of newborns to prevent purulent conjunctivitis. We describe the number and characteristics of OGI case-patients diagnosed among NYC residents over a 12-year period.

Methods
We examined data from two different sources: (1) the NYC Health Department sexually transmitted infections (STI) surveillance registry (January 2006-October 2017) in which OGI cases were defined as laboratory-confirmed infection of the eye or eye appendages; and (2) a hospital discharge database (inpatient and emergency room) for NYC residents admitted to any New York State hospital (inpatient or emergency room discharges, January 2006–December 2016) in which cases of OGI were identified using diagnostic codes corresponding to OGI. We characterized de-duplicated OGI cases identified across these data sources for 2006–2017 and calculated the OGI rate/100,000 reported gonorrhea cases.

Results
Thirty-six OGI cases were identified in STI surveillance data and 55 additional cases in the hospital discharge database. Out of the total of 91 OGI cases, 20 (22%) were ≤1 year (11 males, 9 females), 3 (3.3%) were 2–14 years (all males), and 68 (74.7%) were ≥15 years old. Among the 68 adolescent/adult case-patients, the mean age was 29.04 ± 13.4 years. The majority were males (69.1%, 47/68,) and African American (42.6%, 29/68). The OGI rate in adolescents/adults was 39.95/100,000 gonorrhea cases (females, 35.76; males, 42.31); the rate remained almost constant since 2006 despite the increases in gonorrhea over the past decade. Conjunctivitis was the most common presentation (90.1% of all cases; 82/91), followed by eye appendage infections (2.2%; 2/91). The STI surveillance data revealed the diagnosis of OGI was made mainly by ocular culture (86.1%; 31/36), followed by nucleic acid amplification test (NAAT) (8.3%), or both culture and NAAT (5.6%).

Conclusion
OGI appear to be a rare disease in NYC. The majority of infections occurred among adolescents and adults, likely due to mandated newborn prophylaxis.

Disclosures
All authors: No reported disclosures.
441. Factors Associated with a Change of Antimicrobial Therapy in Patients with Cellulitis Who Started with Amoxicillin–Clavulanate (A/C) Monotherapy
Authors: Collazos Julio , De la Fuente Belén , De la Fuente Javier , Garcia Alicia , Gomez Helena , Suárez-Zarracina Tomás , Rivas-Carmenado Maria , Enriquez Hector , Sánchez Paula , Alonso María , López-Cruz Ian , Martin-Regidor Manuel , Martinez-Alonso Ana , Guerra José , Artero Arturo , Blanes Marino , Asensi Victor 
Published: October 2019

Abstract

Background
Cellulitis is a frequent cause of admission of adult patients to medical wards and A/C monotherapy is commonly used as the initial regimen. Studies evaluating the factors associated with the change of this regimen are lacking.

Methods
Data were extracted from a prospective and observational study of 606 adult patients with cellulitis admitted to several Spanish hospitals. Comorbidities, microbiological, clinical, lab, diagnostic, and treatment data were analyzed and compared according to the continuation/change of A/C. Multiple logistic regression modeling was performed to determine the variables independently associated with A/C switching.

Results
Overall 259 (42.7%) patients started A/C monotherapy, 56 (21.6%) of which were switched to other antimicrobials. Patients switched from A/C developed sepsis (19.6% vs. 8.4%, P = 0.02) and underwent imaging methods (P < 0.01) more commonly than those kept on A/C. These A/C switched patients had higher serum glucose (P = 0.04), creatinine (P < 0.0001), leukocyte (P = 0.006) and neutrophil counts (P < 0.0001). Regarding microbiological data, patients switched from A/C had more frequently pus (P < 0.0001) and blood cultures (P = 0.002) available, a microorganism identified (P < 0.0001) and higher rates of Gram-negative bacilli infections (P = 0.003). Patients switched from initial A/C had also longer hospitalization stays (10.5 vs. 5.2 days, P < 0.00019, longer duration of IV (10.0 vs. 4.3 days, P < 0.0001), and overall antibiotic treatment (16.5 vs. 10.4 days, P < 0.0001) and needed more frequently surgical treatment (25.0 vs. 4.9%, P < 0.0001), specialized follow-up after discharge (36.4 vs. 17.3%, P = 0.0009) and combination therapy after discharge (35.9% vs. 1.1%, P < 0.0001).The variables independently asociated with A/C switch in the multivariate analysis were higher serum creatinine (P = 0.03), neutrophil counts (P = 0.003), days on IV antibiotics (P < 0.0001) and the needed for surgical treatment (P = 0.004)

Conclusion
Patients switched from the initial A/C regimen do not have differences in the predisposing factors, but seem to have more serious cellulitis, characterized by higher neutrophil counts and serum creatinine, needing extended IV antibiotic therapy and additional surgical debridement.

Disclosures
All authors: No reported disclosures.
453. High Burden of Invasive and Severe Group A Streptococcus Disease Among Native Americans on the White Mountain Apache Tribal Lands
Authors: Sutcliffe Catherine , Close Ryan M , Davidson Anne M , Reid Angelina , Quay Dianna , Nicolet Katherine , Brown Laura B , Grant Lindsay , Weatherholtz Robert , McAuley James , Hammitt Laura 
Published: October 2019

Abstract

Background
Native Americans are overrepresented in outbreaks of Group A Streptococcus (GAS) in the United States (US). In 2016, several invasive cases of GAS were detected at the Whiteriver Indian Health Service (IHS) Hospital in Arizona that primarily serves the White Mountain Apache (WMA) Tribe. The objective of this study was to determine the burden of invasive and severe GAS disease among Native Americans on the WMA Tribal lands.

Methods
Prospective population and laboratory-based surveillance for invasive and severe GASinfections was conducted for two years from March 2017 through February 2019. A case was defined as a Native American individual living on or around WMA Tribal lands with GAS isolated from a normally sterile body site (invasive) or from a non-sterile site (e.g., wound, throat, ear) requiring hospitalization (severe). Incidence rates were calculated using the IHS User Population as the denominators. Age-standardized incidence rates were calculated using US Census data from 2015 as the reference group.

Results
157 cases were identified (Year 1: 85; Year 2: 72), including 42 (27%) invasive and 115 (73%) severe cases. Most cases were adults (88.5%; median age: 40.5 years) and had ≥1 underlying medical condition (99.4%), including alcoholism (57.1%), hypertension (37.2%), and diabetes (34.0%). 47.8% of cases had a trigger in the past two weeks, including penetrating trauma (31.8%) and blunt force trauma (14.0%). For 72.9% of cases, a co-infection was detected (most commonly Staphylocccus aureus: 96.8%). 4.5% of cases required amputation and 1.9% died within 30 days of initial culture. The incidence of invasive and severe GAS was 460.9 per 100,000 persons (95% confidence interval: 394.3, 538.8), with no significant difference by year. The incidence was highest among adults ≥65 and lowest among children 5–17 years of age. Age-standardized incidence rates of invasive and severe GAS and invasive only GAS are presented in the Figure.

Conclusion
The WMA community has experienced disproportionately high rates of invasive and severe GAS for over two years. Studies to determine the reservoirs for transmission are urgently needed, as are interventions to reduce the morbidity and mortality associated with these infections.

Disclosures
All authors: No reported disclosures.
456. Dalbavancin, a Long-Acting Lipoglycopeptide Antimicrobial Agent, Reduces Length of Stay and Improves Patient Work Productivity in a Hospital Critical Pathway for Acute Bacterial Skin and Skin Structure Infections (ABSSSI)—the ENHANCE ABSSSI Trial
Authors: McCarthy Matthew W , Keyloun Katelyn R , Gillard Patrick , Choi Justin J , Copp Ronald , Walsh Thomas J 
Published: October 2019

Abstract

Background
Prolonged admissions for acute bacterial skin and skin structure infections (ABSSSI) present an opportunity to improve efficiency and quality of care. A primary reason for admission for ABSSSI is to receive intravenous (IV) antibiotics, where multiple guidelines support shifting care to outpatient settings for appropriate patients. A hospital pathway for ABSSSI that leverages long-acting IV antibiotic therapy, such as dalbavancin, may reduce the length of stay (LOS). The ENHANCE ABSSSI trial (NCT03233438) sought to quantify LOS vs. that of usual care after implementing a new ABSSSI pathway.

Methods
A single-center, pre- vs. post-period pragmatic trial at Weill-Cornell Medical Center assessed usual care for consecutively enrolled ABSSSI patients during an observational period (pre-period). A new ABSSSI pathway was implemented in the post-period, which included (1) identification of eligible admitted ABSSSI patients and (2) treatment with dalbavancin. Those with life-threatening infections, requiring multiple antibiotics/intensive care, or with unstable comorbidities were excluded. Outcomes were assessed over a 44-day follow-up period.

Results
Of 48 and 43 patients enrolled in pre- and post-periods (Figure 1), mean infection-related LOS was reduced in the post-period (3.2 days vs. 4.8 days; P = 0.003; Figure 2 and 3). Similar results were found in an adjusted LOS analysis. Work productivity and activity impairment outcomes significantly improved in the post-period, apart from absenteeism, while quality of life was similar between periods (Figure 4). Complete response to treatment was similar between periods: 50% (pre-period) and 57% (post-period). A greater proportion of total adverse events (AEs) occurred in the post-period (n = 20; 48%) vs. pre-period (n = 3; 6%) with most AEs being mild in severity and not related to antibiotic use; few AEs were serious (7% [n = 3] post-period vs. 2% [n = 1] pre-period). The most common AEs were unrelated infection in the pre-period and fever in the post-period.

Conclusion
After implementing the ENHANCE ABSSSI pathway among eligible patients, LOS was significantly reduced by almost 2 days, with potential improvements in work productivity and the ability to complete daily activities.

Disclosures
All authors: No reported disclosures.
461. Management of ABSSSIs: An Assessment of Knowledge, Competence and Clinical Practices among ID Specialists
Authors: Hurst Simi Thomas , Maeglin John 
Published: October 2019

Abstract

Background
One of the most common bacterial infections overall and among the most common causes for ED referral and/or hospital admission, ABSSSIs continue to impart a significant public health burden. The rising tide of MDROs has limited the clinical utility of many traditional antibiotics and increasing age and comorbid conditions such as diabetes, impaired renal or hepatic function, and CVD disease further complicate patient management strategies, putting patients at increased risk for treatment failure.

Methods
A continuing medical education (CME)-certified clinical practice assessment comprising 25 multiple choice questions that measured ID specialists’ knowledge, competence, confidence and current practices in the management of ABSSSIs. The survey instrument was launched on a website dedicated to continuous professional development on July 27/18. Respondent confidentiality was maintained and responses were de-identified and aggregated prior to analyses.

Results
To date, 2921HCPs, including 2,380 physicians have participated in the activity. Data for ID specialists who had participated as of April 17, 2019 are presented; data collection are ongoing. The majority of ID specialists (68%; n = 268) practiced in the inpatient setting. Despite a relatively high level of confidence in several areas (Table 1 and data not shown), the data identified several knowledge and competence gaps with regard to antimicrobial agent selection, treatment duration, and management of complicated ABSSSIs (Table 2). The most frequently cited barriers to optimal care included: (i) logistical challenges in arranging for appropriate patient follow-up (33%; n = 122); (ii) knowledge about appropriate duration of antibiotic therapy (19%; n = 71); and (iii) access to more expensive antibiotic therapies that may be more effective (19%; n = 71).

Conclusion
This activity identified knowledge and competency gaps in the management of patients with ABSSSIs. These findings will be used to inform the development of educational programs that may help narrow these gaps and improve patient care.

Disclosures
All authors: No reported disclosures.
467. Antimicrobial Resistance and Molecular Analysis of Staphylococcus aureus in Staphylococcal Scalded Skin Syndrome among Children in Korea
Authors: Hong Choi Jae , Lee Hyunju , Hwa Choi Eun 
Published: October 2019

Abstract

Background
Staphylococcal scalded skin syndrome (SSSS) is a blistering and desquamative skin disease caused by the exfoliative toxins of Staphylococcus aureus. SSSS mainly affects children younger than 5 years of age. Although many countries show a predominance of methicillin-susceptible S. aureus (MSSA), recently an increase in cases due to methicillin-resistant S. aureus (MRSA) has been reported. We investigated the molecular characteristics of S. aureus isolated from the children with SSSS in Korea.

Methods
From January 2010 to December 2017, children clinically diagnosed as SSSS under the age of 5 years were enrolled. Cases from 3 different university hospitals in Korea were included. S. aureus isolated from nasal, axillary, or inguinal area of the children were analyzed for multilocus sequence type and exfoliative toxins (eta, etb). Medical records were retrospectively reviewed for clinical characteristics and antimicrobial susceptibility patterns of S. aureus.

Results
A total of 26 cases were enrolled. The mean age was 2.3 years (range, 0–4.8 years). Twenty-two (84.6%) patients were hospitalized. Skin manifestations were classified as follows; generalized (n = 10, 38.5%), intermediate (n = 11, 42.3%), and abortive (n = 5, 19.2%). Twenty-five isolates (96.2%) were resistant to methicillin and macrolide-resistance was found in 92.3% (n = 24). ST89 (n = 21, 80.8%) was the most prevalent clone, with single clones of ST1, ST5, ST72, ST121, and ST1507. The eta gene was detected in 1 (3.8%) MSSA isolate. The etb gene was detected in 14 (53.8%) isolates all of which were ST89. All patients were treated with antibiotics, and the mean duration was 8.3 days regardless of the administration route. Nafcillin or first cephalosporin was most commonly prescribed (n = 20, 76.9%), clindamycin was administered in combination in 9 patients (34.6%) and vancomycin in 4 patients (15.4%). Among the 25 MRSA cases, only 6 (24.0%) were treated with susceptible antibiotics. However, there was no difference in treatment duration according to antimicrobial susceptibility (8.43:8.22 days, P > 0.05).

Conclusion
The molecular epidemiology of S. aureus isolated from the Korean children with SSSS demonstrated the high prevalence of methicillin-resistant ST89 clone that harbors the etb gene.

Disclosures
All authors: No reported disclosures.
480. Molecular Characterization of Multidrug-Resistant Gram-Negative Pathogens in Three Tertiary Care Hospitals in Egypt
Authors: Kholy Amani , Girgis Samia A , Elmanakhly Arwa R , Shetta Mervat A F , El- Kholy Dalia , Zahran Mariam 
Published: October 2019

Abstract

Background
High rates of AMR among Gram-negative bacilli (GNB) have been reported from Egypt for almost 2 decades. Surveillance and identifying the genetic basis of AMR provide important information to optimize patient care. As there is no adequate data on the genetic basis of AMR in Egypt, we aimed to identify the molecular characterization of multi-drug-resistant (MDR) Gram-negative pathogens (GNP).

Methods
Three major tertiary-care hospitals in Egypt participated in the “Study for Monitoring Antimicrobial Resistance Trends” (SMART) from 2014 to 2016. Consecutive GNPs were identified and their susceptibility to antimicrobials were tested. Molecular identification of ESBL, AmpC, and carbapenemase resistance genes was conducted on MDR isolates.

Results
We enrolled 1,070 consecutive Gram-negative isolates; only one isolate per patient according to the standard protocol of (SMART). During 2014–2015, 578 GNP were studied. Enterobacteriaceae comprised 66% of the total isolates. K. pneumoniae and E. coli were the most common (29.8% and 29.4%). K. pneumoniae and E. coli were the predominant organisms in IAI (30.5% and 30.1%, respectively) and UTI (and 38.9% and 48.6%, respectively), while Acinetobacter baumannii was the most prevalent in RTI (40.2%). ESBL producers were phenotypically detected in 53% of K. pneumoniae, and 68% of E. coli. During 2016, 495 GNP were studied. ESBL continued to be high. For E. coli and K. pneunomiea, the most active antimicrobials were amikacin (≥93%), imipenem/meropenem (≥87%) and colistin (97%). Genetic study of ertapenem-resistant isolates and 50% of isolates with ESBL phenotype revealed ESβL production in more than 90% of isolates; blaCTXM-15 was detected in 71.4% and 68.5% in K. pneumoniae and E. coli, respectively, blaTEM-OSBL in 48.5% and47.5% of K. pneumoniae and E. coli, respectively. Carbapenem resistance genes were detected in 45.4% of isolates. In K. pneumoniae, OXA-48 dominated (40.6%), followed by NDM1 (23.7%) and OXA-232 (4.5%).

Conclusion
Our study detected alarming rates of resistance and identified many resistance mechanisms in clinical isolates from Egyptian hospitals. These high rates highlight the importance of continuous monitoring of the resistance trend and discovering the novel resistant mechanisms of resistance, and the underscores a national antimicrobial stewardship plan in Egypt.

Disclosures
All authors: No reported disclosures.