Prevalence and characterization of antimicrobial resistance among gram-negative bacteria isolated from febrile hospitalized patients in central Ethiopia

Background Infectious diseases are among the leading causes of death in many low-income countries, such as Ethiopia. Without reliable local data concerning causative pathogens and antimicrobial resistance, empiric treatment is suboptimal. The objective of this study was to characterize gram-negative bacteria (GNB) as pathogens and their resistance pattern in hospitalized patients with infections in central Ethiopia. Methods Patients ≥ 1 year of age with fever admitted to the Asella Referral and Teaching Hospital from April 2016 to June 2018 were included. Blood and other appropriate clinical specimens were collected and cultured on appropriate media. Antibiotic susceptibility testing (AST) was performed using the Kirby–Bauer method and VITEK® 2. Species identification and detection of resistance genes were conducted using MALDI-ToF MS (VITEK® MS) and PCR, respectively. Results Among the 684 study participants, 54.2% were male, and the median age was 22.0 (IQR: 14–35) years. Blood cultures were positive in 5.4% (n = 37) of cases. Among other clinical samples, 60.6% (20/33), 20.8% (5/24), and 37.5% (3/8) of swabs/pus, urine and other body fluid cultures, respectively, were positive. Among 66 pathogenic isolates, 57.6% (n = 38) were GNB, 39.4% (n = 26) were gram-positive, and 3.0% (n = 2) were Candida species. Among the isolated GNB, 42.1% (16/38) were Escherichia coli, 23.7% (9/38) Klebsiella pneumoniae and 10.5% (4/38) Pseudomonas aeruginosa. In total, 27/38 gram-negative isolates were available for further analysis. Resistance rates were as follows: ampicillin/sulbactam, 92.6% (n = 25); cefotaxime, 88.9% (n = 24); ceftazidime, 74.1% (n = 20); cefepime, 74.1% (n = 20); gentamicin, 55.6% (n = 15); piperacillin/tazobactam, 48.1% (n = 13); meropenem, 7.4% (n = 2); and amikacin, 3.7% (n = 1). The blaNDM-1 gene was detected in one K. pneumoniae and one Acinetobacter baumannii isolate, which carried an additional blaOXA-51 gene. The ESBL enzymes were detected in 81.5% (n = 22) of isolates as follows: TEM, 77.2% (n = 17); CTX-M-1 group, 68.2% (n = 15); SHV group, 27.3% (n = 6); and CTX-M-9 group, 9.1% (n = 2). Based on the in vitro antimicrobial susceptibility results, empiric treatment initiated in 13 of 18 (72.2%) patients was likely ineffective. Conclusion We report a high prevalence of ESBL-producing bacteria (81.5%) and carbapenem resistance (7.4%), with more than half of GNB carrying two or more ESBL enzymes resulting in suboptimal empiric antibiotic therapy. These findings indicate a need for local and national antimicrobial resistance surveillance and the strengthening of antimicrobial stewardship programs.

A Practical Approach to Screening for Strongyloides stercoralis

Strongyloides stercoralis, causative agent of a neglected tropical disease, is a soil-transmitted helminth which may cause lifelong persisting infection due to continuous autoinfection. In the case of immunosuppression, life-threatening hyperinfection and disseminated strongyloidiasis can develop. We propose a pragmatic screening algorithm for latent strongyloidiasis based on epidemiologic exposure and immunosuppression status that can be applied for any kind of immunosuppressive therapy. The algorithm allows the diagnosis of latent strongyloidiasis with optimal accuracy in a well-equipped setting, while for endemic settings where the complete testing array is unavailable, an empiric treatment is generally recommended. Accurate diagnosis and extensive empiric treatment will both contribute to decreasing the current neglect of strongyloidiasis.

Evaluation of the Empiric Treatment of Peritoneal Dialysis-Related Peritonitis

Peritonitis is a serious complication of Peritoneal Dialysis (PD). At our hospital, PD- related peritonitis is treated empirically with intraperitoneal cefazolin plus ceftazidime.

Extensively Drug-Resistant Typhoid Fever in the United States

Cases of extensively drug-resistant (XDR) typhoid fever have been reported in the United States among patients who did not travel internationally. Clinicians should consider if and where the patient travelled when selecting empiric treatment for typhoid fever. XDR typhoid fever should be treated with a carbapenem, azithromycin, or both.

706. Effect of the Covid-19 Pandemic on Rates of Recurrent Clostridiodes difficile Infection in the Veterans Affairs System

Background Clostridiodes difficile infection (CDI) is common and classified as an urgent threat by the US Centers for Disease Control and Prevention. Recurrence (rCDI) occurs in 30% of cases and increases with subsequent episodes. As part of a trial of fecal microbiota transplantation vs. placebo for the prevention of rCDI, rCDI is identified using a case-finding algorithm that screens for potential cases across all Veterans Affairs facilities, a key component of which is a stool test confirming the presence of C. difficile. With the emergence of Covid-19 in the Unites States in early 2020, study personnel observed a decreasing number of rCDI cases. We hypothesized that Covid restrictions and fear of transmission prevented patients from coming to a VA facility to submit a confirmatory stool sample, the standard method of diagnosing rCDI. Accordingly, the algorithm was modified to also identify cases where rCDI was empirically treated, without confirmatory testing. Here we report on the prevalence of empiric treatment of rCDI during the Covid pandemic and changes in lab-conformed cases over time. Methods Cases of potentially rCDI are identified by a weekly query of VA data, using an algorithm that includes laboratory testing results, diagnostic codes, and prescriptions. The ource database is updated daily from every VA facility, encompassing over 8 million Veterans. Potential cases are reviewed by research coordinators using the medical record to determine study eligibility. Beginning June 2020, the algorithm was adjusted to also identify patients with lab confirmation of their first CDI episode but none for their recurrence and identified those who were prescribed treatment for rCDI. Results We observed a reduction in both the number of weekly cases (22.2 vs. 17.4; P < 0.001) which is a 22% decrease after the Covid-19 emergency declaration (figure). Post-declaration, empiric treatment was prescribed to 159 Veterans (mean, 3.3/week). Potential cases of rCDI/week pre- and post Covid-19 pandemic declaration Conclusion There was a significant drop in laboratory-confirmed rCDI associated with Covid-19. Recurrent CDI was frequently empirically treated during the Covid-19 pandemic, potentially exposing many patients with non-CDI diarrhea to unnecessary antimicrobial use and its attendant risks. Disclosures All Authors: No reported disclosures

1425. Revisiting β-Lactams for Treatment of Uncomplicated Urinary Tract Infections: Evaluation of Twice-daily Cephalexin for Empiric Treatment of UTIs

Background Current IDSA guidelines for the treatment of UTIs discourage oral β-lactams based on lack of adequately powered studies to assess efficacy compared to fluoroquinolones or TMP-SMX. However, increasing E. coli and Klebsiella spp. resistance to first-line antibiotics has necessitated the need for alternative agents. Methods This was a single-center retrospective chart review of adult patients discharged from the University of New Mexico ED with twice-daily cephalexin for the treatment of uncomplicated UTIs from January 1, 2019 to December 31, 2019. Patients were excluded if < 18 years of age, received ≥ 10 days of cephalexin, received antibiotics for other indications, received antibiotics within 60 days prior to ED visit, or had structural abnormalities. The primary outcome of this study was the proportion of patients with clinical success 30 days after discharge from the ED. Patients not meeting criteria for clinical failure were classified as clinical success. Clinical failure was defined as return of patient within 30 days due to non-resolving or worsening UTI symptoms or change in antibiotic therapy after discharge based on urine culture and susceptibilities. Results A total of 264 patients were included for evaluation. The average age was 56.0 ± 20.2 years and 82.6% were female. Patients received an average 5.6 ± 0.9 days of antibiotic therapy including IV therapy. Of the 264 patients included for evaluation, 81.1% met criteria for clinical success. Of the patients with clinical failure, 29 (13.6%) required a change in antibiotics based on cultures and sensitivities, 17 (6.4%) returned for non-resolving or worsening symptoms, and 4 (1.5%) required both a change in antibiotics and returned for non-resolving or worsening symptoms. Conclusion Short courses of twice-daily cephalexin appear to be safe and effective for empiric treatment of uncomplicated UTIs. Adding β -lactams back to the antibiotic armamentarium for UTI treatment may delay the development of resistance to non- β -lactam antibiotics, ensuring their future utility. Disclosures All Authors: No reported disclosures

1349. How Anchored is the Chancre? A Chart Review of Syphilis Treatment by a Safety Net Emergency Department in Atlanta, GA

Background Since reaching its nadir in 2000, syphilis has re-emerged as a public health threat in the U.S. The incidence of syphilis is disproportionately high in Atlanta, the epicenter of the HIV epidemic in the U.S. South. Given that syphilis infection is a strong predictor of HIV infection, identifying patients with syphilis is an important and underutilized method for connecting patients to HIV prevention and care services. Emergency departments (EDs) act as a critical access point to care in safety net health systems. We describe the recognition and empiric treatment of syphilis in the ED of Grady Healthcare System, a safety net hospital serving Atlanta. Methods We performed a retrospective chart review on all reactive rapid plasma reagin (RPR) tests collected from patients 18 years and older at the Grady ED from 5/1/20 to 10/31/20. We abstracted reported reason for testing, diagnosis, treatment administered, and location of treatment from the electronic health record. Results From 5/1/20 to 10/31/20, 148 patients with reactive RPR tests were identified. Reasons for testing were broad and included the evaluation of neurologic symptoms (47), genital/anal lesions (31), and a history of syphilis (18) (Table 1). 74 patients had presumed active syphilis (50%), 34 had previously treated syphilis (23%), 12 had false positives (8%), and 28 had an unclear diagnosis (19%) (Table 2). Of those with presumed primary syphilis who were discharged from the ED, 53% (8/15) received empiric treatment in the ED; 59% (10/17) of those with secondary syphilis received empiric treatment prior to discharge. Of the patients discharged from the ED, clinical follow up was indicated for 52% (31/59) given lack of empiric treatment or of confirmed prior treatment. Contact was attempted for 39% (12/31), but only 29% (9/31) were ultimately treated at Grady. Table 1: Abstracted Reasons for Testing for Syphilis in the ED For ED patients from 5/1/20-10/31/20 who had reactive RPRs, reasons for syphilis testing were taken from the chief complaint, history, or medical decision making documentation of ED providers, admitting providers, or consultants. Table 2: Syphilis Diagnoses of ED patients with reactive RPRs ED patients with a positive RPR from 5/1/20-10/31/20 were chart reviewed to determine their diagnosis. Previous RPR, treponemal antibodies, CSF results, media images, progress notes, and descriptions by medical staff were reviewed to attempt to retroactively determine the most likely syphilis diagnosis. Conclusion Reactive RPRs were common in this acute care setting and most represented active syphilis infection. Empiric treatment was most likely to be provided for patients with clear syphilis syndromes. However, a majority of patients who were discharged without empiric treatment did not receive follow up. Institutional protocols for following up reactive tests after discharge represent an opportunity to connect patients with syphilis treatment and HIV prevention services. Disclosures All Authors: No reported disclosures