Third-Generation Cephalosporin Resistance and Associated Discordant Antibiotic Treatment in Emergency Department Febrile Urinary Tract Infections.

STUDY OBJECTIVE: Third-generation cephalosporin-resistant (3GCR) Escherichia coli, Klebsiella pneumoniae, and Proteus mirabilis (EKP) are an increasingly common cause of community-onset urinary tract infections (UTIs) in the United States. The 3GCR antimicrobial resistance pattern in these Enterobacterales species is most commonly due to production of extended-spectrum ß-lactamases. We sought to provide contemporary, emergency department (ED)-focused data on 3GCR-EKP UTI regional prevalence, presentation, antibiotic susceptibility, and empiric treatment patterns, and outcomes. METHODS: We performed a retrospective cohort study of all adults admitted with a febrile UTI at 21 Kaiser Permanente Northern California EDs between January 2017 and June 2019. Inclusion criteria included fever; admitting diagnosis of UTI, pyelonephritis, or sepsis; and ED urine culture with greater than 100,000 colony-forming units/mL of an EKP species. 3GCR was defined as in vitro resistance to ceftriaxone, ceftazidime, or both. 3GCR-EKP cases were compared with non-3GCR-EKP controls for the following: demographics, comorbidities, presenting clinical features, urinary isolate antimicrobial susceptibility, treatment, and clinical outcomes. The primary outcome measure was the rate of discordant initial empiric antibiotic treatment (administered within 6 hours of ED arrival) when compared with antimicrobial susceptibility testing. Secondary outcomes included hospital length of stay and 90-day mortality, adjusted for comorbidities and severity of illness. RESULTS: There were 4,107 patients (median age 73 years and 35% men) who met study inclusion criteria. Of these patients, 530 (12.9%) had a 3GCR-EKP urinary tract infection. The proportion of subjects possessing risk factors for a health care-associated or extended-spectrum ß-lactamase infection was 92.8% of case patients and 86.1% of controls. When comparing 3GCR-EKP case and non-3GCR-EKP control isolates, ciprofloxacin susceptibility rates were 21% versus 88%, and piperacillin/tazobactam susceptibility rates were 89% versus 97%, respectively. Initial empiric antibiotic therapy was discordant with antimicrobial susceptibility testing results in 63% of case patients versus 7% of controls (odds ratio 21.0; 95% confidence interval 16.9 to 26.0). The hospital length of stay was longer for 3GCR-EKP case patients, with an adjusted mean difference of 29.7 hours (95% CI 19.0 to 40.4). Ninety-day mortality was 12% in case patients versus 8% in controls (adjusted odds ratio 1.56; 95% confidence interval 1.07 to 2.28). CONCLUSION: In this large, 2017 to 2019 Northern California ED study, nearly 13% of febrile EKP UTIs requiring hospitalization were caused by 3GCR-EKP, and in these cases, initial empiric therapy was often discordant with antimicrobial susceptibility testing. 3GCR-EKP infections were associated with a longer hospital length of stay and higher 90-day mortality. Similar data from other regions and for outpatient UTIs are needed.

A Nonopioid, Nonbenzodiazepine Treatment Approach for Intractable Nausea and Vomiting in the Emergency Department.

GOAL: We sought to assess the feasibility and efficacy of a treatment protocol for nausea and vomiting using the combination of chlorpromazine, a dopamine antagonist antiemetic, and ketamine, a nonopioid analgesic. BACKGROUND: Increasing numbers of patients with cannabis use disorder are presenting to emergency departments with a poorly understood syndrome characterized by intractable nausea and vomiting. METHODS: This is a prospective, observational study involving a convenience sample of patients with unexplained nausea and vomiting. Subjects were given ketamine 15 mg slow intravenous push and chlorpromazine 12.5 mg intravenous over 15 minutes. Outcomes were number of episodes of emesis after study drug administration; change in nausea severity; change in pain severity; adverse events; and patient satisfaction. RESULTS: We enrolled 28 subjects on 30 emergency department visits. Twenty-three subjects (82%) reported at least weekly cannabis use with 19 reporting daily use. Initial symptoms were severe, with median pain and nausea scores both 10. After receiving study medication, the mean decrease in pain score over 120 minutes was 4.1 (95% confidence interval: 3.2, 5.0) and the mean decrease in nausea score was 4.9 (95% confidence interval: 4.0, 5.8). There were no adverse events. All 28 subjects who were asked reported they would want to receive these medications again. CONCLUSION: In this single-center study, the majority of patients presenting with intractable nausea and vomiting reported heavy cannabis use, and symptoms were severe. The combination of chlorpromazine plus ketamine resulted in rapid, definitive cessation of symptoms in most of these patients without the need for opioids or benzodiazepines.

Emergency Department Urinary Tract Infections Caused by Extended-Spectrum ß-Lactamase-Producing Enterobacteriaceae: Many Patients Have No Identifiable Risk Factor and Discordant Empiric Therapy Is Common.

STUDY OBJECTIVE: Community-onset urinary tract infections (UTIs) caused by extended-spectrum ß-lactamase (ESBL)-producing Enterobacteriaceae, which are resistant to ceftriaxone and usually coresistant to fluoroquinolones, are increasing worldwide. We investigate and describe in detail UTIs caused by ESBL-producing Enterobacteriaceae in our emergency department (ED), and determine the proportion that occurred in patients without health care-associated risk factors and who received discordant initial antibiotic therapy. METHODS: At an urban public hospital in Northern California, microbiology staff prospectively reviewed ED urine culture results weekly for 1 year and presumptively identified ESBL-producing isolates by ceftriaxone plus ceftazidime resistance. For isolates associated with a clinical UTI, patient demographic and case clinical features were abstracted retrospectively. Health care-associated infections were defined by standard risk factors plus aged 65 years or older, bladder catheter, urologic procedure, functional dependence, or antibiotics in the previous 90 days. Community-associated infections were defined by absence of these. A subset of community-associated ESBL-producing Escherichia coli isolates underwent genotyping. Electronic health record query was used to determine the denominator of ED UTI patients who underwent urine culture during the study period. RESULTS: Between August 2016 and July 2017, there were 1,045 unique ED patients diagnosed with a UTI, whose specimens underwent culture. There were 62 ESBL-producing isolates (5.9%; 95% confidence interval [CI] 4.6% to 7.5%). Selected characteristics of the entire ESBL UTI cohort were median age 50 years, 37 (60%) patients were women, 28 (44%) Hispanic, 11 (18%) had been hospitalized in the previous 3 months, 19 (31%) had pyelonephritis, 49 (79%) of isolates were E coli, 44 (71%) were levofloxacin-resistant, and 24 (23%) nitrofurantoin-resistant. Initial antibiotic choice was discordant with isolate susceptibility in 26 of 56 cases (46%; 95% CI 33% to 60%), and the initial oral antibiotic prescred was discordant in 19 of 41 cases (46%; 95% CI 31% to 63%). Twenty-seven infections (44%; 95% CI 31% to 57%) were categorized as community-associated. Eight patients with community-associated infection were women younger than 50 years, with no comorbidities and no more than 1 UTI in the previous year. Of 12 community-associated E coli isolates tested, all were confirmed to harbor ESBL genes; the CTX-M1 ß-lactamase gene was found in 8 (67%); 4 belong to genotype ST131. CONCLUSION: At this single Northern California ED, greater than 5% of culture-proven UTI were caused by ESBL-producing Enterobacteriaceae, and in nearly half of cases there was no identifiable health care-associated risk factor. Levofloxacin co-resistance and discordant antibiotic therapy were common.

Accuracy and Discomfort of Different Types of Intranasal Specimen Collection Methods for Molecular Influenza Testing in Emergency Department Patients.

STUDY OBJECTIVE: While development is under way of accurate, point-of-care molecular tests for influenza infection, the optimal specimen type for molecular tests remains unclear. Compared with standard nasopharyngeal swab specimens, less invasive nasal swab and midturbinate swab specimens may cause less patient discomfort and be more suitable for routine emergency department (ED) testing, although possibly at the expense of diagnostic accuracy. We compare both the accuracy of a polymerase chain reaction molecular influenza test and discomfort between these 3 intranasal specimen types. METHODS: A convenience sample of adult and pediatric patients with influenza-like illness and presenting to 2 Northern California EDs and 2 EDs in Santiago, Chile, was prospectively enrolled during the 2015 to 2016 influenza season. Research nurses collected nasopharyngeal swab, midturbinate swab, and nasal swab specimens from each subject and assessed discomfort on a validated 6-point scale. Specimens were tested for influenza A and B by real-time polymerase chain reaction at reference laboratories. Outcome measures were comparison of test performance between nasal swab and midturbinate swab, when compared with a reference standard nasopharyngeal swab; and comparison of discomfort between all 3 specimen types. RESULTS: Four hundred eighty-four subjects were enrolled, and all 3 swabs were obtained for each subject; 14% were children. The prevalence of influenza (A or B) was 30.0% (95% confidence interval [CI] 26.0% to 34.8%). The sensitivity for detecting influenza was 98% (95% CI 94.25% to 99.65%) with the midturbinate swab versus 84.4% (95% CI 77.5% to 89.8%) with the nasal swab, difference 13.6% (95% CI 8.2% to 19.3%). Specificity was 98.5% (95% CI 96.6% to 99.5%) with the midturbinate swab versus 99.1% (95% CI 97.4% to 99.8%) with the nasal swab, difference -0.6% (95% CI -1.8% to 0.6%). Swab discomfort levels correlated with the depth of the swab type. Median discomfort scores for the nasal swab, midturbinate swab, and nasopharyngeal swab were 0, 1, and 3, respectively; the median differences were nasopharyngeal swab-midturbinate swab 2 (95% CI 1 to 2), nasopharyngeal swab-nasal swab 3 (95% CI 2 to 3), and midturbinate swab-nasal swab 1 (95% CI 1 to 2). CONCLUSION: Compared with the reference standard nasopharyngeal swab specimen, midturbinate swab specimens provided a significantly more comfortable sampling experience, with only a small sacrifice in sensitivity for influenza detection. Nasal swab specimens were significantly less sensitive than midturbinate swab. Our results suggest the midturbinate swab is the sampling method of choice for molecular influenza testing in ED patients.

Low-Dose Ketamine Infusion for Emergency Department Patients with Severe Pain.

OBJECTIVE: Use of low-dose ketamine infusions in the emergency department (ED) has not previously been described, despite routine use in perioperative and other settings. Our hypothesis was that a low-dose ketamine bolus followed by continuous infusion would 1) provide clinically significant and sustained pain relief; 2) be well tolerated; and 3) be feasible in the ED. METHODS: We prospectively administered 15 mg intravenous ketamine followed immediately by continuous ketamine infusion at 20 mg/h for 1 hour. Optional morphine (4 mg) was offered at 20, 40, and 60 minutes. Pain intensity, vitals signs, level of sedation, and adverse reactions were assessed for 120 minutes. RESULTS: A total of 38 patients were included with a median initial numerical rating scale (NRS) pain score of 9. At 10 minutes, the median reduction in pain score was 4, with 7 patients reporting a score of 0. At 60 and 120 minutes, 25 and 26 patients, respectively, reported clinically significant pain reduction (decrease NRS score > 3). Heart rate, blood pressure, respiratory rate, and oxygen saturation remained stable. Mild or moderate side effects including dizziness, fatigue, and headache were common. Patient satisfaction was high; 85% reported they would have this medication again for similar pain. CONCLUSION: A low-dose ketamine infusion protocol provided significant pain relief with mostly mild side effects and no severe adverse events.

The first 500: initial experience with widespread use of low-dose ketamine for acute pain management in the ED.

OBJECTIVES: The objective of this study is to describe the clinical use and safety profile of low-dose ketamine (LDK) (0.1-0.3 mg/kg) for pain management in the emergency department (ED). METHODS: This was a retrospective case series of consecutive patients given LDK for pain at a single urban ED between 2012 and 2013. Using a standardized data abstraction form, 2 physicians reviewed patient records to determine demographics, indication, dose, route, disposition, and occurrence of adverse events. Adverse events were categorized as minor (emesis, psychomimetic or dysphoric reaction, and transient hypoxia) and serious (apnea, laryngospasm, hypertensive emergency, and cardiac arrest). Additional parameters measured were heart rate and systolic blood pressure. RESULTS: Five hundred thirty patients received LDK in the ED over a 2-year period. Indications for LDK were diverse. Median patient age was 41 years, 55% were women, and 63% were discharged. Route of administration was intravenous in 93% and intramuscular in 7%. Most patients (92%) received a dose of 10 to 15 mg. Comorbid diseases included hypertension (26%), psychiatric disorder (12%), obstructive airway disease (11%), and coronary artery disease (4%). There was no significant change in heart rate or systolic blood pressure. Thirty patients (6%) met our criteria for adverse events. Eighteen patients (3.5%) experienced psychomimetic or dysphoric reactions. Seven patients (1.5%) developed transient hypoxia. Five patients (1%) had emesis. There were no cases of serious adverse events. Agreement between abstractors was almost perfect. CONCLUSION: Use of LDK as an analgesic in a diverse ED patient population appears to be safe and feasible for the treatment of many types of pain.

Abnormal urinalysis results are common, regardless of specimen collection technique, in women without urinary tract infections.

BACKGROUND: Voided urinalysis to test for urinary tract infection (UTI) is prone to false-positive results for a number of reasons. Specimens are often collected at triage from women with any abdominal complaint, creating a low UTI prevalence population. Improper collection technique by the patient may affect the result. At least four indices, if positive, can indicate UTI. OBJECTIVE: We examine the impact of voided specimen collection technique on urinalysis indicators of UTI and on urine culture contamination in disease-free women. METHODS: In this crossover design, 40 menstrual-age female emergency department staff without UTI symptoms collected urine two ways: directly in a cup ("non-clean") and midstream clean catch ("ideal"). Samples underwent standard automated urinalysis and culture. Urinalysis indices and culture contamination were compared. RESULTS: The proportion of abnormal results from samples collected by "non-clean" vs. "ideal" technique, respectively, were: leukocyte esterase (>trace) 50%, 35% (95% confidence interval for difference -6% to 36%); nitrites (any) 2.5%, 2.5% (difference -2.5 to 2.5%); white blood cells (>5/high-powered field [HPF]) 50%, 27.5% (difference 4 to 41%); bacteria (any/HPF) 77.5%, 62.5%, (difference -7 to 37%); epithelial cells (>few) 65%, 30% (difference 13 to 56%); culture contamination (>1000 colony-forming units of commensal or >2 species) 77%, 63% (difference -5 to 35%). No urinalysis index was positively correlated with culture contamination. CONCLUSION: Contemporary automated urinalysis indices were often abnormal in a disease-free population of women, even using ideal collection technique. In clinical practice, such false-positive results could lead to false-positive UTI diagnosis. Only urine nitrite showed a high specificity. Culture contamination was common regardless of collection technique and was not predicted by urinalysis results.

Diabetic Foot Infections in the Emergency Department.

Diabetic foot infection (DFI) is among the most common diabetic complications requiring hospitalization. Prompt emergency department diagnosis and evidence-based management can prevent eventual amputation and associated disability and mortality. Underlying neuropathy, arterial occlusion, immune dysfunction, and hyperglycemia-associated dehydration and ketoacidosis can all contribute to severity and conspire to make DFI diagnosis and management difficult. Serious complications include osteomyelitis, necrotizing infection, and sepsis. Practice guidelines are designed to assist frontline providers with correct diagnosis, categorization, and treatment decisions. Management generally includes a careful lower extremity examination and plain x-ray, obtaining appropriate tissue cultures, and evidence-based antibiotic selection tailored to severity.

The Intersection of Substance Use Disorders and Infectious Diseases in the Emergency Department.

Substance use disorders (SUDs) intersect clinically with many infectious diseases, leading to significant morbidity and mortality if either condition is inadequately treated. In this article, we will describe commonly seen SUDs in the emergency department (ED) as well as their associated infectious diseases, discuss social drivers of patient outcomes, and introduce novel ED-based interventions for co-occurring conditions. Clinicians should come away from this article with prescriptions for both antimicrobial medications and pharmacotherapy for SUDs, as well as an appreciation for social barriers, to care for these patients.

Effective analgesia with low-dose ketamine and reduced dose hydromorphone in ED patients with severe pain.

OBJECTIVE: We assessed the analgesic effect and feasibility of low-dose ketamine combined with a reduced dose of hydromorphone for emergency department (ED) patients with severe pain. METHODS: This was a prospective observational study of adult patients with severe pain at an urban public hospital. We administered 0.5 mg of intravenous (IV) hydromorphone and 15 mg of IV ketamine, followed by optional 1 mg hydromorphone IV at 15 and 30 minutes. Pain intensity was assessed at 12 intervals over 120 minutes using a 10-point verbal numerical rating scale (NRS). Patients were monitored throughout for adverse events. Dissociative side effects were assessed using the side effects rating scale for dissociative anesthetics. RESULTS: Of 30 prospectively enrolled patients with severe pain (initial mean NRS, 9), 14 reported complete pain relief (NRS, 0) at 5 minutes; the mean reduction in NRS pain score was 6.0 (SD, 3.2). At 15 minutes, the mean reduction in NRS pain score was 5.0 (SD, 2.8). The summed pain intensity difference and percent summed pain intensity difference scores were 25 (95% confidence interval [CI], 21-30) and 58% (95% CI, 49-68) at 30 minutes and 41 (95% CI, 34-48) and 50% (95% CI, 42-58) at 60 minutes, respectively. Most patients (80%) reported only weak or modest side effects. Ninety percent of patients reported that they would have the medications again. No significant adverse events occurred. CONCLUSIONS: Low-dose ketamine combined with a reduced dose hydromorphone protocol produced rapid, profound pain relief without significant side effects in a diverse cohort of ED patients with acute pain.

Methicillin-resistant Staphylococcus aureus and Pseudomonas aeruginosa community acquired pneumonia: Prevalence and locally derived risk factors in a single hospital system.

Objectives: Current American Thoracic Society/Infectious Disease Society of America (ATS/IDSA) community-acquired pneumonia (CAP) guidelines expand the CAP definition to include infections occurring in patients with recent health care exposure. The guidelines now recommend that hospital systems determine their own local prevalence and predictors of Pseudomonas aeruginosa and methicillin-resistant Staphylococcus aureus (MRSA) among patients satisfying this new broader CAP definition. We sought to carry out these recommendations in our system, focusing on the emergency department, where CAP diagnosis and initial empiric antibiotic selection usually ooccur. Methods: We performed a retrospective cohort study of patients admitted with CAP through any of 3 EDs in our hospital system in Northern California between November 2019 and October 2021. Inclusion criteria included an ED admission diagnosis of pneumonia or sepsis, fever or hypothermia, leukocytosis or leukopenia, and consistent chest imaging result. SARS-CoV-2-positive cases were excluded. We abstracted variables historically associated with P. aeruginosa and MRSA. Outcome measures were prevalence of P. aeruginosa and MRSA in the overall clinically defined cohort and among microbiologically confirmed cases and predictors of P. aeruginosa or MRSA isolation, as determined by univariate logistic regression, bootstrapped least absolute shrinkage and selection operator, and random forest analyses. Additionally, we describe the iterative process used and challenges encountered in carrying out the new ATS/IDSA guideline recommendations. Results: There were 1133 unique patients who satisfied our definition of clinically defined CAP, of whom 109 (9.6%) had a bacterial pathogen isolated. There were 24 P. aeruginosa isolates and 11 MRSA isolates in 33 patients. Thus, the prevalence P. aeruginosa and MRSA was 2.9% in the overall CAP cohort, but 30.3% in the microbiologically confirmed cohort. The most important predictors of either P. aeruginosa or MRSA isolation were tracheostomy (odds ratio [OR] 22.08; 95% confidence interval [CI] 10.39-46.96) and gastrostomy tube (OR 14.7; 95% CI 7.14-30.26). Challenges included determining the suspected infection type in patients admitted simply for "sepsis"; interpreting dictated radiology reports; determining functional status, presence of indwelling lines and tubes, and long-term care facility residence from the electronic health record; and correctly attributing culture results to pneumonia. Conclusion: Prevalence of MRSA and P. aeruginosa was low among patients admitted in our medical system with CAP - now broadly defined - but high among those with a microbiologically confirmed bacterial etiology. Our locally derived predictors of MRSA and P. aeruginosa can be used to aid our emergency physicians in empiric antibiotic selection for CAP. Findings from this project might inform efforts at other institutions.

Low rate of syphilis screening among high-risk emergency department patients tested for gonorrhea and chlamydia infections.

BACKGROUND: Implementing national recommendations for syphilis screening is not feasible in the emergency department (ED) setting. The purpose of this study was to determine the syphilis screening rate among ED patients tested for gonorrhea and chlamydia (GC/CT) and the syphilis prevalence among those who were tested. METHODS: A 1-year retrospective cohort study in an urban ED. At the time of this study, there were no explicit syphilis screening guidelines and testing was at the discretion of the treating physician. We determined the proportion of all GC/CT-tested patients who also underwent syphilis screening and the prevalence of syphilis among this group. Predictors of syphilis screening among patients tested for GC/CT were identified. RESULTS: GC/CT tests were performed in 3951 (4.7%) of the 83,988 ED visits, of which 332 (8.4%) were reactive. The mean age of GC/CT-tested patients was 22.6 ± 12 years, most were female (67%), black (47%), and English speaking (74%). Syphilis screening was completed in 1218 (31%) of the GC/CT-tested patients, 17 tests (1.4%) were reactive, which included 8 (0.7%) unique patients with newly diagnosed syphilis. In multivariable analysis, the following variables were predictive of syphilis screening: empirical GC/CT treatment (odds ratio [OR]: 1.9, 95% confidence interval [CI]: 1.6-2.3), evaluation in the low acuity section of the ED (OR: 1.8, 95% CI: 1.4-2.3), a reactive GC/CT test (OR: 1.3, 95% CI: 1.0-1.6), and age ≤25 years (OR: 1.2, 95% CI: 1.0-1.4). CONCLUSION: Among ED patients tested for GC/CT, less than one-third were screened for syphilis. Failure to screen these patients likely resulted in missed opportunities for syphilis diagnosis.

Antimicrobial resistance in uncomplicated urinary tract infections in 3 California EDs.

BACKGROUND: Increased trimethoprim/sulfamethoxazole (TMP/SMX) resistance has led to changes in empiric treatment of female urinary tract infections (UTI) in the emergency department (ED), particularly increased use of fluoroquinolones (Acad Emerg Med.2009;16(6):500-507). Whether prescribing changes have affected susceptibility in uropathogens is unclear. Using narrow-spectrum agents and therapy tailored to local susceptibilities remain important goals. OBJECTIVE: The primary goal of this study is to characterize the susceptibility patterns of uropathogens among ambulatory female ED patients with UTI. Its secondary goal is to identify demographic or clinical factors predictive of resistance to narrow-spectrum agents. METHODS: This was a cross-sectional study of women with suspected UTI referred to a trial of computer kiosk-aided treatment of UTI in 3 Northern California EDs. Demographic and clinical data were gathered from the kiosk and chart, and features associated with resistance were identified by bivariate and multivariable regression analysis. RESULTS: Two hundred eighty-three participants, aged 15 to 84 years, were diagnosed with UTI and cultured. One hundred thirty-five (48%) of cultures were positive, with full susceptibilities reported (81% Escherichia coli). Only 2 isolates (1.5%) were fluoroquinolone resistant. Resistance to TMP/SMX was 18%, to nitrofurantoin 5%, and to cefazolin 4%. Seventy-four percent were sensitive to all 3 narrow-spectrum agents. Resistance to narrow-spectrum agents did not vary significantly by diagnosis, age, recent UTI, or any clinical or demographic factors; but overall, there was a trend toward lower resistance rates in our population than in our hospitals' published antibiograms. CONCLUSION: In our population of ambulatory female ED patients, resistance to TMP/SMX is just below the 20% threshold that the Infectious Disease Society of America recommends for continued empiric use (Clin Infect Dis.1999;29(4):745-758, Clin Infect Dis.2011;52(5):e103-120), whereas resistance to other narrow-spectrum agents, such as nitrofurantoin and cephalexin, may be lower than published antibiograms for our sites. Fluoroquinolone resistance remains very low.

Genetic Predictive Factors for Nonsusceptible Phenotypes and Multidrug Resistance in Expanded-Spectrum Cephalosporin-Resistant Uropathogenic Escherichia coli from a Multicenter Cohort: Insights into the Phenotypic and Genetic Basis of Coresistance.

Antimicrobial resistance in urinary tract infections (UTIs) is a major public health concern. This study aims to characterize the phenotypic and genetic basis of multidrug resistance (MDR) among expanded-spectrum cephalosporin-resistant (ESCR) uropathogenic Escherichia coli (UPEC) causing UTIs in California patient populations. Between February and October 2019, 577 ESCR UPEC isolates were collected from patients at 6 clinical laboratory sites across California. Lineage and antibiotic resistance genes were determined by analysis of whole-genome sequence data. The lineages ST131, ST1193, ST648, and ST69 were predominant, representing 46%, 5.5%, 4.5%, and 4.5% of the collection, respectively. Overall, 527 (91%) isolates had an expanded-spectrum ß-lactamase (ESBL) phenotype, with blaCTX-M-15, blaCTX-M-27, blaCTX-M-55, and blaCTX-M-14 being the most prevalent ESBL genes. In the 50 non-ESBL phenotype isolates, 40 (62%) contained blaCMY-2, which was the predominant plasmid-mediated AmpC (pAmpC) gene. Narrow-spectrum ß-lactamases, blaTEM-1B and blaOXA-1, were also found in 44.9% and 32.1% of isolates, respectively. Among ESCR UPEC isolates, isolates with an ESBL phenotype had a 1.7-times-greater likelihood of being MDR than non-ESBL phenotype isolates (P < 0.001). The cooccurrence of blaCTX-M-15, blaOXA-1, and aac(6')-Ib-cr within ESCR UPEC isolates was strongly correlated. Cooccurrence of blaCTX-M-15, blaOXA-1, and aac(6')-Ib-cr was associated with an increased risk of nonsusceptibility to piperacillin-tazobactam, cefepime, fluoroquinolones, and amikacin as well as MDR. Multivariate regression revealed the presence of blaCTX-M-55, blaTEM-1B, and the ST131 genotype as predictors of MDR. IMPORTANCE The rising incidence of resistance to expanded-spectrum cephalosporins among Escherichia coli strains, the most common cause of UTIs, is threatening our ability to successfully empirically treat these infections. ESCR E. coli strains are often MDR; therefore, UTI caused by these organisms often leads to treatment failure, increased length of hospital stay, and severe complications (D. G. Mark, Y.-Y. Hung, Z. Salim, N. J. Tarlton, et al., Ann Emerg Med 78:357-369, 2021, https://doi.org/10.1016/j.annemergmed.2021.01.003). Here, we performed an in-depth analysis of genetic factors of ESCR E. coli associated with coresistance and MDR. Such knowledge is critical to advance UTI diagnosis, treatment, and antibiotic stewardship.

Emergency department ultrasonographic probe contamination and experimental model of probe disinfection.

STUDY OBJECTIVE: We evaluate the frequency of emergency department (ED) ultrasonographic probe contamination and the bacterial species involved and evaluate probe cleaning and disinfection methods. METHODS: This was a 3-part observational cross-sectional study. Surveillance cultures were taken of linear and curvilinear probes on 3 ultrasonographic machines between patient encounters. Cultures of uncovered probes were taken immediately after scanning of skin and soft tissue infections. After experimental probe contamination with methicillin-resistant Staphylococcus aureus (MRSA), we assessed 3-step disinfection by sequential cleaning with a dry towel, saline solution-moistened towel, and quaternary ammonia germicidal wipe and 1-step disinfection by germicidal wipe alone. Cultures were obtained by applying the probe to a blood agar plate. RESULTS: In part 1, of 164 surveillance cultures obtained from 6 probes on 29 sampling days during 11 months, 111 (67%; 95% confidence interval [CI] 60% to 74%) grew normal skin flora or environmental flora, 52 had no growth (32%; 95% CI 25% to 39%), and 2 (1.2%; 95% CI 0.3% to 4.3%) grew a clinically important pathogen. In part 2, 14 of 20 (70%; 95% CI 48% to 85%) cultures taken after skin and soft tissue infection scanning produced heavy growth of a clinically important pathogen, including 13 S aureus (5 MRSA). In part 3, cleaning with a dry and moist towel reduced but did not eliminate MRSA. The germicidal wipe step resulted in no growth in 15 of 15 (100%; 95% CI 80% to 100%) cultures in 3-step disinfection and in 9 of 10 (90%; 95% CI 60% to 98%) when used alone. CONCLUSION: Skin and environmental flora are commonly present on ultrasonographic probes between patient encounters in our ED; however, clinically important pathogens are uncommon. S aureus (including MRSA) frequently contaminates uncovered probes during skin and soft tissue infection scanning, but in an experimental model, MRSA appears to be reliably removed by a quaternary ammonia germicidal wipe if the probe is partially cleaned first.

Physician-initiated rapid HIV testing in an urban emergency department: comparison of testing using a point-of-care versus a laboratory model.

STUDY OBJECTIVE: We compare the outcomes of 2 models of physician-initiated rapid HIV testing in an emergency department (ED). METHODS: One-year retrospective cohort comparing 2 6-month models of physician-initiated rapid HIV testing, point-of-care versus laboratory. Patients aged 12 years or older and able to give verbal consent were eligible for physician-initiated rapid HIV testing if their treating physician believed testing was clinically indicated. During the point-of-care phase, nursing staff performed oral fluid testing. During the laboratory phase, the laboratory performed whole-blood testing. The proportion of potentially eligible patients who had physician-initiated rapid HIV testing ordered (order rate), proportion of ordered tests completed (test completion rate), and proportion of potentially eligible patients who completed testing (overall testing rate) during each phase were assessed. ED length of stay and testing times were also compared. RESULTS: For the point-of-care versus laboratory phase, respectively, there were 24,345 potentially eligible patients versus 26,363; order rate was 3.3% versus 2.4% (P<.001); test completion rate was 75.3% versus 86.8% (P<.001); overall testing rate was 2.5% versus 2.1% (P=.009). Eighteen (3.0%) of the point-of-care-tested patients and 15 (2.7%) of the laboratory-tested patients had reactive tests (P=0.02). The total testing time was greater in the laboratory phase (88 versus 66 minutes; P<.001); however, there was no significant difference in the length of stay between phases (6.2 versus 6.9 hours; P=.15). CONCLUSION: Relatively few ED patients undergo physician-initiated rapid HIV testing regardless of whether a point-of-care or laboratory approach is used. Differences exist in most outcome measures when point-of-care and laboratory models are compared, which should be considered when testing is implemented.

HIV screening in an urban emergency department: comparison of screening using an opt-in versus an opt-out approach.

OBJECTIVE: We compare outcomes of opt-in and opt-out HIV screening approaches in an urban emergency department. METHODS: This was a 1-year prospective observational study comparing 2 6-month screening approaches. Eligibility for opt-in and opt-out screening was identical: aged 15 years or older, medically stable, and able to complete general consent. During the opt-in phase, triage nurses referred patients to HIV testers stationed at triage, who obtained separate opt-in written consent and performed rapid oral fluid tests. During the opt-out phase, registration staff conducted integrated opt-out consent and then referred patients to HIV testers. We assessed the proportion of potentially eligible patients who were offered screening (screening offer rate), the proportion offered screening who accepted (screening acceptance rate), the proportion who accepted screening and subsequently completed testing (test completion rate), and the proportion of potentially eligible patients who completed testing (overall screening rate) during each phase. RESULTS: For the opt-in versus the opt-out phases, respectively, there were 23,236 potentially eligible patients versus 26,757, screening offer rate was 27.9% versus 75.8% (P<.001), screening acceptance rate was 62.7% versus 30.9% (P<.001), test completion rate was 99.8% versus 74.6% (P<.001), and overall screening rate was 17.4% versus 17.5% (P = .90). CONCLUSION: A significantly higher proportion of patients were offered HIV screening with an opt-out approach at registration. However, this was offset by much higher screening acceptance and test completion rates with the opt-in approach at triage. Overall screening rates with the 2 approaches were nearly identical.

A Dual Enzyme-Based Biochemical Test Rapidly Detects Third-Generation Cephalosporin-Resistant CTX-M-Producing Uropathogens in Clinical Urine Samples.

Extended-spectrum ß-lactamase (ESBL)-producing Gram-negative bacteria (GNB) are increasingly identified as the cause of both community and healthcare-associated urinary tract infections (UTIs), with CTX-Ms being the most common ESBLs identified. CTX-M-producing GNB are resistant to most ß-lactam antibiotics and are frequently multidrug-resistant, which limits treatment options. Rapid diagnostic tests that can detect ESBL-producing GNB, particularly CTX-M producers, in the urine of patients with UTIs are needed. Results from such a test could direct the selection of appropriate antimicrobial therapy at the point-of-care (POC). In this study, we show that a chromogenic, dual enzyme-mediated amplification system (termed DETECT [dual-enzyme trigger-enabled cascade technology]) can identify CTX-M-producing GNB from unprocessed urine samples in 30 minutes. We first tested DETECT against a diverse set of recombinant ß-lactamases and ß-lactamase-producing clinical isolates to elucidate its selectivity. We then tested DETECT with 472 prospectively collected clinical urine samples submitted for urine culture to a hospital clinical microbiology laboratory. Of these, 118 (25%) were consistent with UTI, 13 (11%) of which contained ESBL-producing GNB. We compared DETECT results in urine against a standard phenotypic method to detect ESBLs, and polymerase chain reaction and sequencing for CTX-M genes. DETECT demonstrated 90.9% sensitivity and 97.6% specificity (AUC, 0.937; 95% confidence interval, 0.822-1.000), correctly identifying 10 of 11 urine samples containing a clinically significant concentration of CTX-M-producing GNB (including Escherichia coli, Klebsiella pneumoniae, and Proteus mirabilis). Our results demonstrate the clinical potential of DETECT to deliver diagnostic information at the POC, which could improve initial antibiotic selection.

The benefit of empiric treatment for methicillin-resistant Staphylococcus aureus.

Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) has emerged as a major pathogen causing skin and soft tissue infections (SSTI). It is unclear whether treatment with antibiotics active in vitro against CA-MRSA improves patient outcomes. At our institution, where there is a high rate of CA-MRSA SSTI, we have adopted an empiric treatment algorithm that promotes both the use of antibiotics likely active against CA-MRSA and early incision and drainage of abscesses. The objective of this research was to study the effectiveness of an empiric treatment algorithm for SSTI directed against CA-MRSA. The study was a retrospective chart review. Treatment was categorized as either conforming or not conforming to the algorithm. Outcomes were categorized as worsening of infection or improvement, according to predefined criteria. There were 50 consecutive Emergency Department patients treated as outpatients for MRSA SSTI. Treatment conformed to the algorithm in 29 of 50 cases. Clinical failure occurred in 3% of cases treated according to the algorithm, compared with 62% of those not treated according to the algorithm (p < 0.001). Among 37 cases that underwent immediate incision and drainage, initial treatment with antibiotics active in vitro against the MRSA isolate was associated with a decreased clinical failure rate when compared to those treated with inactive antibiotics (0% vs. 67%, p < 0.001). Empiric treatment of CA-MRSA SSTI according to an algorithm that promotes use of antibiotics active in vitro against CA-MRSA is associated with improved clinical outcomes.

A comparison of HIV testing in the emergency department and urgent care.

BACKGROUND: Although national guidelines recommend universal human immunodeficiency virus (HIV) testing, emergency departments (EDs) may choose to limit testing to certain patients, such as those triaged to urgent care (UC). OBJECTIVE: To compare the results of rapid HIV testing in an urban ED with an affiliated UC. METHODS: This was a retrospective analysis of an HIV testing program that included screening, which was initiated by triage nurses, and diagnostic testing, which was initiated by clinicians. Eligible patients were ≥ 12 years old and medically stable. RESULTS: From April 2005 through December 2006, HIV tests were completed in 6196 (8.3%) of the 74,331 ED visits and 3256 (8.8%) of the 37,169 UC visits. Screening accounted for 5009 (80.8%) of the ED tests and 2914 (89.5%) of the UC tests, and diagnostic testing accounted for the remainder. Eighty (1.3%) of the ED tests and 21 (0.6%) of the UC tests were positive (p = 0.0024). Compared with newly diagnosed HIV-positive ED patients, HIV-positive UC patients were less likely to have CD4 counts < 200 cells/µL (adjusted odds ratio 0.19, 95% confidence interval 0.05-0.65). CONCLUSION: Although the yield of HIV testing is greater among ED patients, UC patients are diagnosed at a less advanced stage of illness.