Urinary Source Research Articles

131. Duration of Therapy for the Treatment of Gram-Negative Bloodstream Infections

BackgroundWhile current guidelines suggest a total treatment duration of 7 to 14 days for gram-negative bloodstream infections (GN-BSI), there is mounting evidence to suggest that shorter durations may be sufficient. This study compared the treatment outcomes of patients who received short duration therapy (6–10 days) with those who received long durations (11–15 days).MethodsThis was a retrospective study of adult patients who grew an aerobic gram-negative organism from a blood culture while admitted at Strong Memorial Hospital between May 2016 and May 2018. The primary outcome was a composite of mortality and relapsed GN-BSI with the same organism within 90 days of index culture. Secondary outcomes included clinical resolution at end of therapy (EOT), length of stay (LOS), 30-day readmission rate, Clostridoides difficile infection (CDI), development of recurrent GN-BSI resistant to prior antibiotic therapy, and development of multi-drug-resistant (MDR) GN-BSI within 90 days. Appropriate therapy was defined as an antibiotic with confirmed in vitro susceptibility that was either parenteral or a highly bioavailable oral antibiotic (fluoroquinolones or sulfamethoxazole–trimethoprim).ResultsOf 600 patients screened, 116 were included in the long duration group and 34 patients in the short-duration group. The majority of patients had a urinary source of infection (59.3%). The primary composite outcome occurred in 11.8% of the short duration group compared with 10.3% in the long (P > 0.999). There was no difference in clinical resolution at EOT, LOS, or rates of CDI, MDR GN-BSI, recurrent GN-BSI resistant to prior therapy, or 30-day readmission. Patients in the long duration group were discharged with longer appropriate outpatient courses (8 days vs. 0.5 days, P < 0.001), which remained significant when including lower bioavailability agents (e.g., oral β lactams) (8 days vs. 5 days, P < 0.001).ConclusionThere was no difference in clinical outcomes between the long and short duration therapy for treatment of GN-BSI. This study may support shorter treatment durations for uncomplicated GN-BSI, but should be interpreted cautiously given the smaller sample size.Disclosures All authors: No reported disclosures.

1114. Oral β-lactams for the Treatment of Escherichia coli Bacteremia Secondary to Complicated Urinary Tract Infections Including Pyelonephritis

BackgroundComplicated urinary tract infections (cUTI) including pyelonephritis may result in bacteremia, increasing the rate of morbidity and mortality. The Infectious Diseases Society of America recommends a fluoroquinolone as empiric therapy or trimethoprim/sulfamethoxazole as definitive therapy for acute pyelonephritis (AP). Oral β-lactams (BL) are considered sub-optimal based on historical efficacy data with aminopenicillins and variable bioavailability. Increasing resistance and toxicity with preferred agents, justifies further evaluation of oral BL for E. coli bacteremia secondary to urinary source.MethodsThis was a single-center, retrospective cohort study of patients with E. coli bacteremia secondary to AP or cUTI who received oral step-down therapy with a BL or non-BL. The primary outcome was the rate of clinical success defined by microbiological cure, clinical cure, and infection-related readmission. Secondary outcomes were time to oral step-down, total days of therapy, length of hospital stay, incidence of therapy escalation, 30-day readmissions, and antibiotic-associated adverse events.ResultsA total of 46 patients were included, with 23 patients in each group. The difference in clinical success between the BL and non-BL groups was not statistically significant (91.3% vs. 100%, P = 0.489). The most frequent oral step-down agents prescribed were cephalexin and ciprofloxacin. The median time to oral step-down was significantly lower in the non-BL group (4.39 vs. 3.41 days, P = 0.038), and the median duration of therapy in each group was 15 days. No patients required therapy escalation after oral step-down or had infection-related readmission within 30 days of discharge.ConclusionThe observed clinical success rate of 91.3% remains consistent with previous studies evaluating oral BL as step-down therapy for Enterobacteriaceae bloodstream infections. The results of this study support the safety and efficacy of oral BL as step-down therapy for E. coli bacteremia due to cUTI, although larger studies may be beneficial.Disclosures All authors: No reported disclosures.

165. Comparative Effectiveness of Oral Fluoroquinolones vs. β-Lactams for the Treatment of Patients with Enterobacteriaceae Bloodstream Infections

BackgroundFluoroquinolones (FQ) are associated with unacceptable rates of adverse drug events (ADE) and drug resistance. Safe and effective alternative oral agents are needed for definitive treatment of Enterobacteriaceae bloodstream infections (BSI). This study aims to determine whether treatment failure rates were similar in patients who received FQ or β-lactams (BL) for stepdown treatment of Enterobacteriaceae BSI.MethodsWe conducted a retrospective cohort study comparing oral BL vs. FQ as definitive therapy for patients with BSI due to Escherichia coli, Klebsiella spp., or Proteus spp. Eligible patients were ≥18 years old with a monomicrobial BSI treated with a single definitive oral antibiotic. Patients with a total antibiotic treatment duration of <6 or >21 days were excluded. Groups were matched based on age and gender. The primary outcome was treatment failure defined as recurrence or all-cause mortality within 90 days with a 10% non-inferiority margin. Secondary outcomes were death or recurrence within 30 and 90 days, symptomatic urinary tract infection (UTI) or BSI within 30 days, and the safety outcome of antibiotic-related ADE.ResultsThe average age was 68 years, with 94% males. In the BL group, 80% had a urinary source of infection vs. 69% of the FQ group. The majority of patients had source control (88% of BL group vs. 83% of FQ group). The most common pathogens were E. coli (66%) and K. pneumoniae (24%). Cefpodoxime (71%) and ciprofloxacin (85%) were the most commonly used oral antibiotics. The average duration of oral therapy was 9.2 vs. 9.6 days and total duration was 14.4 vs. 13.9 days in the BL vs. FQ group, respectively. The primary outcome occurred in 15.4% of the BL group vs. 12.3% of the FQ group (P = 0.8002, RR = 0.80, 95% CI = 0.33–1.90). No deaths were directly attributed to infection. Symptomatic UTI or BSI within 30 days occurred in 20% of BL patients vs. 21.5% of FQ patients (P = 1.0000, RR = 1.07, 95% CI = 0.55–2.11). Mortality or recurrence at 30 days were similar between groups (4.6% of BL group vs. 9.2% of FQ group, P = 0.4920, RR = 2.00, 95% CI = 0.52–7.66). One FQ patient experienced an antibiotic-related ADE (C. difficile infection).ConclusionBL are non-inferior to FQ and appear to be as effective for oral step-down treatment of Enterobacteriaceae BSI without the associated risks.Disclosures All authors: No reported disclosures.

Inpatient healthcare-associated bloodstream infections in older people.

This retrospective study describes inpatient healthcare-associated bloodstream infections (HABSI) in older adults and explores whether urinary catheters (presence/insertion/removal) were related to HABSI events. One hundred and sixty-seven HABSI events were identified, predominantly (124, 74%) with Gram-negative bacteria. HABSI was attributed to a urinary source in 110 patients (66%), with over half (63, 57%) of these associated with urinary catheters. Catheter-associated HABSI may be avoidable and potential preventative strategies are discussed.

Prevalence of Catheter-Associated Urinary Tract Infections in Neurosurgical Intensive Care Patients - The Overdiagnosis of Urinary Tract Infections.

Background: Hospital-acquired infections (HAIs) are profound causes of prolonged hospital stay and worse patient outcomes. HAIs pose serious risks, particularly in neurosurgical patients in the intensive care unit, as these patients are seldom able to express symptoms of infection, with only elevated temperatures as the initial symptom. Data from Center for Disease Control (CDC) and the Infectious Disease Society of America (IDSA) have shown that of all HAIs, urinary tract infections (UTIs) have been grossly over-reported, resulting in excessive and unnecessary antibiotic usage.Methods: We conducted a retrospective analysis of 686 adult patients that were evaluated by the neurosurgery service at Arrowhead Regional Medical Center between July 2018 and March 2019. Inclusion criteria were adults greater than 18 years of age with neurosurgical pathology requiring a minimum of one full day admission to the intensive care unit (ICU), and an indwelling urinary catheter. Exclusion criteria were patients under the age of 18, those who did not spend any time in the ICU, or with renal pathologies such as renal failure.Results: We reviewed 686 patients from the neurosurgical census. In total, 146 adult patients with indwelling urinary catheters were selected into the statistical analysis. Most individuals spent an average of 8.91 ± 9.70 days in the ICU and had an indwelling catheter for approximately 8.14 ± 7.95 days. Forty-two out of the 146 individuals were found to have a temperature of 100.4°F or higher. Majority of the patients with an elevated temperature had an infectious source other than urine, such as sputum (22 out of 42, 52.38%), blood (three out of 42, 7.14%) or CSF (one out of 42, 2.38%). We were able to find only two individuals (4.76%) with a positive urine culture and no evidence of other positive cultures or deep vein thrombosis.Conclusions: Our analysis shows evidence to support the newest IDSA guidelines that patients with elevated temperatures should have a clinical workup of all alternative etiologies prior to testing for a urinary source unless the clinical suspicion is high. This will help reduce the rate of unnecessary urine cultures, the over-diagnosis of asymptomatic bacteriuria, and the overuse of antibiotics. Based on our current findings, all potential sources of fever should be ruled out prior to obtaining urinalysis, and catheters should be removed as soon as they are not needed. Urinalysis with reflex to urine culture should be reserved for those cases where there remains a high index of clinical suspicion for a urinary source.

Incidence and Risk Factors Associated with Multi-Drug-Resistant Pathogens in a Critically Ill Trauma Population: A Retrospective Cohort Study.

Background: Multi-drug resistance is considered a serious health threat particularly in the intensive care unit (ICU) setting. Studies evaluating multi-drug-resistant (MDR) pathogens in critically ill trauma patients are limited. The objectives were to describe the incidence of MDR, extensive-drug-resistant (XDR), and pan-drug-resistant (PDR) organism growth in ICU patients admitted with traumatic injuries and to identify any risk factors associated with MDR growth. Patients and Methods: This was a retrospective single-center cohort study of all ICU adult patients identified via the institution's trauma registry from January 1, 2016 to August 31, 2017. Patients were included if they had positive culture growth with susceptibility data taken during the index hospitalization. Patients were excluded if their cultures were drawn within 48 hours of emergency department triage. Study groups were defined based on the presence of at least one MDR pathogen during the index hospitalization. Results: A total of 2,578 charts were reviewed and 95 patients (mean age, 60 years; 66 males [69%]) with 201 total cultures were included. The majority of positive cultures were from respiratory (69%) and urinary (16%) sources. Of the 201 positive cultures, the majority of species identified was Enterobacteriaceae (47%), Staphylococcus (32%), Enterococcus (7%), Acinetobacter (5%), and Pseudomonas (3%). Of the 95 patients with positive cultures, the incidence of MDR, XDR, and PDR organisms was found to be 31%, 17%, and 0%, respectively. Augmented renal clearance (ARC) was the only risk factor associated with an increased risk for MDR organism growth (adjusted odds ratio 9.78, 95% confidence interval [CI] 2.56-37.41; p = 0.001). Conclusions: In this cohort of critically ill trauma patients, the incidence of an MDR pathogen occurred in 31% of patients. This is the first study to find an association of ARC and multi-drug resistance, which should be further validated as a potential cause for MDR organisms.

Mitral Valve Endocarditis with Perforation from a Urinary Source: An Unusual Case and Literature Review

Aerococcus urinae (AU) is a rare pathogen, identified as gram-positive, catalase-negative coccus that grows in pairs and clusters which has been reported to mainly cause urinary tract infections (UTI), especially in elderly males. Treatment for this microorganism is usually with beta-lactams although cultures with antibiotic susceptibility testing are imperative. We present a case of AU endocarditis initially treated with IV antibiotics; nevertheless, the patient required emergent mitral valve replacement due to severe mitral insufficiency and perforation. We also present an analysis with high-yield points summarizing epidemiology, risk factors, microbiology, clinical features, diagnostic workup, and management of AU in general and AU endocarditis. Finally, we post a literature review of relevant cases and the impact of different variables associated with it.

Risk factors for treatment failure in patients receiving β-lactam/β-lactamase inhibitor combinations for Enterobacteriaceae bloodstream infection: A retrospective, single-centre, cohort study

The aim of this study was to investigate risk factors for treatment failure in patients receiving in vitro-active therapy with β-lactam/β-lactamase inhibitor (BL/BLI) for Enterobacteriaceae bloodstream infection (E-BSI). This was a retrospective, single-centre study of patients diagnosed with E-BSI at an Italian centre over a 4-year period. Exclusion criteria were age <18 years, clinical data unavailable, polymicrobial BSI, failure to receive in vitro-active therapy and death within 72 h from drawing the index blood culture. Patients who received BL/BLI as appropriate empirical and/or definitive therapy for ≥50% of the total treatment duration were selected. The primary endpoint was all-cause 30-day mortality. The secondary endpoint was 90-day relapse. Of 1319 eligible patients, 835 were selected. A total of 714 received BL/BLI as appropriate empirical therapy, of whom 522 remained on BL/BLI as definitive therapy and 192 shifted to another antibiotic for <50% of the treatment duration; 121 received BL/BLI as definitive therapy only. Non-susceptibility to extended-spectrum cephalosporins (NS-ESCs) was detected in 207 episodes (24.8%). All-cause 30-day mortality was 6.8%. In multivariate analysis adjusted for NS-ESC, independent predictors of mortality were Charlson comorbidity index, septic shock, Proteus spp. and CVC-related BSI, whilst urinary source was a protective factor. The 90-day relapse rate was 4.2%. Immunosuppression was the main independent predictor for relapse. BL/BLI was the most common antibiotic administered to patients with E-BSI in this cohort. Among patients appropriately treated with BL/BLI, failure rates were low and were primarily associated with underlying diseases, clinical severity at BSI onset and infection source.

Impact of Pseudomonas aeruginosa bacteraemia in a tertiary hospital: Mortality and prognostic factors

Background and objectivesPseudomonas aeruginosa bacteraemia is associated with a very high mortality, conditioned by comorbidity, source, severity of the episode and lack of adequate treatment. The aim of the study is to know the mortality and prognostic factors of bacteraemia by P. aeruginosa in our hospital. Patients and methodsWe conducted a retrospective study of P. aeruginosa bacteraemia detected between 2009 and 2014. Epidemiological, clinical and microbiological characteristics were described. A risk factor analysis for mortality was performed. ResultsWe analysed 110 episodes of bacteraemia, which was more frequent in men of advanced age and with a history of hospitalisation, comorbidity and immunosuppression. Most of the bacteraemias were secondary (mainly of respiratory or urinary source) and led to a significant clinical deterioration. The presence of antibiotic resistance was very high, with 27.3% of multiresistant strains. Empirical treatment was adequate in 60.0% and 92.3% for definite treatment. Overall mortality was 37.3% and attributable mortality was 29.1%. The most important prognostic factors were Charlson index ≥3, history of haematologic malignancy, neutropenia and previous use of corticosteroids, source of bacteraemia, Pitt index ≥4, renal insufficiency, adequate definite treatment, empiric treatment with piperacillin/tazobactam in severe episodes and focus control. ConclusionP. aeruginosa bacteraemia is associated with a very high mortality, possibly more related to previous comorbidity and severity of the episode than to the treatment chosen. However, the main goal in management remains to optimise treatment, including focus control.

1072. Streamlining to Oral β-Lactam vs. Fluoroquinolone as Definitive Therapy for Enterobacteriaceae Bacteremia

BackgroundOral treatment strategies for Enterobacteriaceae bacteremia (EB) are controversial, with both β-lactams (BL) and fluoroquinolones (FQ) used in clinical practice. FQ may be preferred for their high bioavailability, but other oral antibiotics are needed due to concerns of resistance and adverse effects. As an effort to facilitate antibiotic stewardship, BL should be explored as an additional oral option for EB treatment.MethodsThis retrospective study compared clinical characteristics and outcomes in patients with EB treated with BL vs. FQ as definitive oral therapy between January 2013 and July 2017. Adult patients diagnosed with their first incidence of EB and transitioned from IV antibiotics to either study antibiotic class were included. Primary and secondary outcomes assessed recurrence, collateral damage, readmission, and all-cause mortality.ResultsA total of 173 patients were included (BL n = 59, FQ n = 114). Median age was 70 years, Pitt bacteremia score was 2 (range 0–7), and Charlson Comorbidity Index was 5 (0–12); all were comparable between groups. Urinary source of infection was most common (57%). The majority of oral BL courses used cefpodoxime (63%). More patients in FQ vs. BL had a prior transplant (9% vs. 0%, P = 0.05), presence of abscess (11% vs. 0%, P = 0.01), and Infectious Diseases consultation (63% vs. 34%, P = 0.0001). Onset of EB in an intensive care unit was more common in BL vs. FQ (24% vs. 10%, P = 0.01). Median duration of IV and oral therapy was 5 vs. 4 days, P = 0.22 and 11 vs. 12 days, P = 0.17 in BL and FQ, respectively. Recurrence within 90 days was 7% in BL and 4% in FQ, P = 0.49 (adjusted OR 1.44, 95% CI 0.31–6.66; P = 0.64). Multivariate analysis identified liver cirrhosis (OR 16.89, 95% CI 1.06–268.32; P = 0.05) as an independent predictor of recurrence within 90 days. All secondary outcomes were similar between BL vs. FQ: superinfection within 90 days (10% vs. 9%, P = 0.76), C. difficile infection within 90 days (3% vs. 1%, P = 0.27), 30-day readmission (15% vs. 20%, P = 0.43), all-cause 30-day mortality (0% vs. 3%, P = 0.55).ConclusionIn our cohort of patients with EB, clinical outcomes were similar between those treated with oral BL compared with FQ. Oral BL may be considered for definitive treatment of EB, although further investigation in larger studies is needed.Disclosures All authors: No reported disclosures.

Collaborative Method Performance Study of the Measurement of Nicotine, Its Metabolites, and Total Nicotine Equivalents in Human Urine.

Background: Biomarkers of tobacco exposure have a central role in studies of tobacco use and nicotine intake. The most significant exposure markers are nicotine itself and its metabolites in urine. Therefore, it is important to evaluate the performance of laboratories conducting these biomarker measurements.Methods: This report presents the results from a method performance study involving 11 laboratories from 6 countries that are currently active in this area. Each laboratory assayed blind replicates of seven human urine pools at various concentrations on three separate days. The samples included five pools blended from smoker and nonsmoker urine sources, and two additional blank urine samples fortified with pure nicotine, cotinine, and hydroxycotinine standards. All laboratories used their own methods, and all were based on some form of liquid chromatography/tandem mass spectrometry.Results: Overall, good agreement was found among the laboratories in this study. Intralaboratory precision was good, and in the fortified pools, the mean bias observed was < + 3.5% for nicotine, approximately 1.2% for hydroxycotinine, and less than 1% for cotinine (1 outlier excluded in each case). Both indirect and direct methods for analyzing the glucuronides gave comparable results.Conclusions: This evaluation indicates that the experienced laboratories participating in this study can produce reliable and comparable human urinary nicotine metabolic profiles in samples from people with significant recent exposure to nicotine.Impact: This work supports the reliability and agreement of an international group of established laboratories measuring nicotine and its metabolites in urine in support of nicotine exposure studies. Cancer Epidemiol Biomarkers Prev; 27(9); 1083-90. ©2018 AACR.

Gram-negative bloodstream infections in hemodialysis patients: A retrospective study .

Bloodstream infections (BSIs) are an important cause of hospitalizations and mortality among hemodialysis (HD) patients. Epidemiology of these infections is changing, with increasing rates of Gram-negative pathogens, including resistant ones. Few studies have focused on the characteristics and outcomes of these infections. We aimed to document the causative pathogens of BSIs in HD patients and their clinical outcomes during 2008-2015, and to compare risk factors, clinical features, appropriateness of therapy, and outcomes between patients with Gram-negative vs. Gram-positive BSIs. A single-center retrospective cohort study. Charts of 120 HD patients hospitalized with first BSI were reviewed. A total of 120 patients were included, 61 episodes of Gram-negative (51.8%) and 59 episodes of Gram-positive bacteria (49.2%). Source of infection was significantly more likely to be urinary or abdominal among patients with Gram-negative infection. Otherwise, no statistically significant differences were documented between groups in terms of baseline characteristics, presentation of infection and outcomes. Most Gram-negative BSIs were caused by enterobacteriaceae, followed by Pseudomonas spp. Previous clinical or surveillance cultures added little to accurate prediction of the causative organism. In a cohort of HD patients with BSI, no significant differences were found between Gram-negative and Gram-positive BSIs, besides source of infection. A urinary or abdominal source strongly suggests a Gram-negative pathogen. Otherwise, patient's characteristics, clinical presentation, and previous cultures, all cannot accurately predict the causative pathogen of BSI, and broad-spectrum antibiotics should be used empirically. .

Planning to halve Gram-negative bloodstream infection: getting to grips with healthcare-associated Escherichia coli bloodstream infection sources

A thorough understanding of the local sources, risks, and antibiotic resistance for Escherichia coli bloodstream infection (BSI) is required to focus prevention initiatives and therapy. To review the sources and antibiotic resistance of healthcare-associated E.coli BSI. Sources and antibiotic resistance profiles of all 250 healthcare-associated (post 48 h) E.coli BSIs that occurred within our secondary and tertiary care hospital group from April 2014 to March 2017 were reviewed. Epidemiological associations with urinary source, gastrointestinal source, and febrile neutropenia-related BSIs were analysed using univariable and multivariable binary logistic regression models. E.coli BSIs increased 9% from 4.0 to 4.4 per 10,000 admissions comparing the 2014/15 and 2016/17 financial years. Eighty-nine cases (36%) had a urinary source; 30 (34%) of these were classified as urinary catheter-associated urinary tract infections (UTIs). Forty-five (18%) were related to febrile neutropenia, and 38 (15%) had a gastrointestinal source. Cases were rarely associated with surgical procedures (11, 4%) or indwelling vascular devices (seven, 3%). Female gender (odds ratio: 2.3; 95% confidence interval: 1.2-4.6) and older age (1.02; 1.00-1.05) were significantly associated with a urinary source. No significant associations were identified for gastrointestinal source or febrile neutropenia-related BSIs. Forty-seven percent of the isolates were resistant to ciprofloxacin, 37% to third-generation cephalosporins, and 22% to gentamicin. The gastrointestinal tract and febrile neutropenia together accounted for one-third of E.coli BSI locally but were rare associations nationally. These sources need to be targeted locally to reduce an increasing trend of E.coli BSIs.

Association Between Carbapenem Resistance and Mortality Among Adult, Hospitalized Patients With Serious Infections Due to Enterobacteriaceae: Results of a Systematic Literature Review and Meta-analysis.

This study quantified mortality associated with serious infections caused by carbapenem-resistant (CRE) and carbapenem-susceptible Enterobacteriaceae (CSE). A systematic literature review was conducted, evaluating outcomes in hospitalized patients with CRE infections from a blood, urinary, pulmonary, or intra-abdominal source. A meta-analysis (MA) calculating odds ratios (ORs) for mortality was performed. Twenty-two studies met the criteria for inclusion in the MA: 12 included mortality data for CRE vs CSE populations. Compared with CSE, CRE was associated with a significantly higher risk of overall mortality (OR, 3.39; 95% confidence interval [CI], 2.35–4.89), as was monotherapy (vs combination therapy) treatment of patients with CRE infections (OR, 2.19; 95% CI, 1.00–4.80). These results document the increased mortality associated with serious CRE infections compared with CSE infections among hospitalized adults. It will be important to reevaluate the mortality in CRE and CSE populations, especially among patients who receive early appropriate therapy, as new antibiotics become available.

Impacto de la bacteriemia por Pseudomonas aeruginosa en un hospital de tercer nivel: mortalidad y factores pronósticos

Background and objectivesPseudomonas aeruginosa bacteraemia is associated with a very high mortality, conditioned by comorbidity, source, severity of the episode and lack of adequate treatment. The aim of the study is to know the mortality and prognostic factors of bacteraemia by P.aeruginosa in our hospital. Patients and methodsWe conducted a retrospective study of P.aeruginosa bacteraemia detected between 2009 and 2014. Epidemiological, clinical and microbiological characteristics were described. A risk factor analysis for mortality was performed. ResultsWe analysed 110 episodes of bacteraemia, which was more frequent in men of advanced age and with a history of hospitalisation, comorbidity and immunosuppression. Most of the bacteraemias were secondary (mainly of respiratory or urinary source) and led to a significant clinical deterioration. The presence of antibiotic resistance was very high, with 27.3% of multiresistant strains. Empirical treatment was adequate in 60.0% and 92.3% for definite treatment. Overall mortality was 37.3% and attributable mortality was 29.1%. The most important prognostic factors were Charlson index ≥3, history of haematologic malignancy, neutropenia and previous use of corticosteroids, source of bacteraemia, Pitt index ≥4, renal insufficiency, adequate definite treatment, empiric treatment with piperacillin/tazobactam in severe episodes and focus control. ConclusionP.aeruginosa bacteraemia is associated with a very high mortality, possibly more related to previous comorbidity and severity of the episode than to the treatment chosen. However, the main goal in management remains to optimise treatment, including focus control.

Aerococcus urinae, Alloscardovia omnicolens, and Actinotignum schaalii: the AAA Minor League Team of Urinary Tract Infection Pathogens

In clinical microbiology laboratories, advancements in the methods used for routine organism identification have facilitated more accurate species level resolution. This, along with increasing knowledge regarding “new” pathogens, has provided new insights into biology and has revealed clinical associations not previously known. Aerococcus urinae, Alloscardovia omnicolens, and Actinotignum schaalii are Gram-positive bacteria associated with urinary tract infections but can also be members of the urinary tract microbiota. In addition, invasive infections have been reported for the three bacteria, usually with a urinary tract source. Importantly, the use of routine biochemical testing methods for identification of these bacteria can result in misidentification or the incorrect determination that they are not clinically significant. Of these bacteria, only A. urinae has antimicrobial susceptibility testing criteria and interpretative breakpoints. Microbiologists and clinicians need to be aware of these urinary tract pathogens and how to correctly identify them.

Epidemiology and impact of bloodstream infections among kidney transplant recipients: A retrospective single-center experience.

Bloodstream infection (BSI) represents an important source of morbidity and mortality, as well as an increasing therapeutic challenge, among solid organ transplant recipients. Understanding the epidemiological and microbiological characteristics of BSI following renal transplantation is paramount to the implementation of appropriate preventative and therapeutic measures. We conducted a retrospective review of all BSI episodes occurring between July 2009 and April 2016 in adult patients, who received a renal transplant at Royal Free London hospital. A total of 116 episodes of BSI occurred in 87 patients, 43 (49.4%) of them men. The mean age at BSI was 54.37±12.81years. Late-onset BSI (>12months post transplant) represented 55.2%, with the median time to BSI being 16.28month. Sixty-seven patients had single BSI and 20 had recurrent episodes. Enterobacteriaceae were responsible for 73.7% of BSI, with Escherichia coli the commonest causative organism (46.6%). The urinary tract was the most frequent source of infection in 56.9%. Among the E.coli infections, 100% of the tested isolates were sensitive to meropenem, ertapenem, tigecycline, and fosfomycin, and >90% were sensitive to piperacillin-tazobactam, amikacin, and colistin. Lower susceptibility rates were encountered for ceftriaxone (70.6%), amoxicillin-clavulanic acid (48.1%), cotrimoxazole (40.4%), trimethoprim (37.3%), and amoxicillin (21.6%). During BSI, the median serum creatinine increased from a reference of 131μmol/L to a peak of 219μmol/L. Acute kidney injury (AKI) complicated 75/116 BSI episodes (64.7%)-stage 1: 34, stage 2: 31, and stage 3 AKI: 10 episodes. After 3months, the median creatinine remained elevated at 146μmol/L. The 3-month mortality rate was 8% (7/87), and the death-censored graft loss was 6.9% (6/87). No significant difference was seen between BSI of urinary and non-urinary sources in the incidence of AKI (χ2 =0.24, P=.6) or the percentage of creatinine change between baseline and peak and 3-month creatinines (P=.2 and .7 respectively). Urinary tract infection remains the commonest source of systemic infection among kidney transplant recipients and resistance to commonly used frontline antibiotics is common; thus, prevention and early detection are paramount. The appropriate choice of initial empirical antibiotic is vital to improve the outcome. Each unit needs to understand the epidemiology of organisms causing BSI in their transplant patients and their antibiotic susceptibilities.

Prophylactic antibiotics following radical cystectomy reduces urinary tract infections and readmission for sepsis from a urinary source

IntroductionUrinary tract infections (UTI) and sepsis contribute significantly to the morbidity associated with cystectomy and urinary diversion in the first 30 days. We hypothesized that continuous antibiotic prophylaxis decreased UTIs in the first 30 days following radical cystectomy. MethodsPatients with urothelial carcinoma of the bladder who underwent a radical cystectomy with urinary diversion for bladder cancer at Oregon Health and Science University from January 2014 to May 2015 were included in the study. The ureteral stents were kept for 3 weeks in both groups. In October 2014, we enacted a Department Quality Initiative to reduce UTIs. Following the initiative, all radical cystectomy patients were discharged home on antibiotic prophylaxis following a postoperative urine culture obtained during hospitalization. To evaluate the effectiveness of the initiative, the last 42 patients before the initiative were compared to the first 42 patients after the initiative with regard to the rate of UTI in the first 30 days following surgery. We used a combination of comprehensive chart review and the American College of Surgeons′ National Surgical Quality Improvement Program (NSQIP) to determine UTI and readmission for urosepsis in the first 30 days following surgery. This ensured accurate capture of all patients developing a UTI. ResultsA total of 12% in the prophylactic antibiotic group had a documented UTI, whereas 36% in the no antibiotic group had a urinary tract infection (P<0.004). A total of 1 (2%) patient in the antibiotic group was readmitted for urosepsis whereas 7 (17%) patients in the no antibiotic group were admitted for urosepsis (P = 0.02). There was no association noted between urine culture at discharge and the development of UTI in the 30-day postdischarge period (P = 0.75). The median time to UTI was 19 days and the most common organism was Enterococcus (32%). Thirty-percent of patients not receiving prophylaxis developed a UTI 1 day after ureteral stent removal. No patients had a UTI following stent removal in the prophylaxis group. No adverse antibiotic related events were noted. ConclusionProphylactic antibiotics in the 30 days following radical cystectomy is associated with a significant decrease in urinary tract infections and readmission from urosepsis after surgery.

Whole genome analysis of cephalosporin-resistant Escherichia coli from bloodstream infections in Australia, New Zealand and Singapore: high prevalence of CMY-2 producers and ST131 carrying blaCTX-M-15 and blaCTX-M-27.

To characterize MDR Escherichia coli from bloodstream infections (BSIs) in Australia, New Zealand and Singapore. We collected third-generation cephalosporin-resistant (3GC-R) E. coli from blood cultures in patients enrolled in a randomized controlled trial from February 2014 to August 2015. WGS was used to characterize antibiotic resistance genes, MLST, plasmids and phylogenetic relationships. Antibiotic susceptibility was determined using disc diffusion and Etest. A total of 70 3GC-R E. coli were included, of which the majority were ST131 (61.4%). BSI was most frequently from a urinary source (69.6%), community associated (62.9%) and in older patients (median age 71 years). The median Pitt score was 1 and ICU admission was infrequent (3.1%). ST131 possessed more acquired resistance genes than non-ST131 (P = 0.003). Clade C1/C2 ST131 predominated (30.2% and 53.5% of ST131, respectively) and these were all ciprofloxacin resistant. All clade A ST131 (n = 6) were community associated. The predominant ESBL types were blaCTX-M (80.0%) and were strongly associated with ST131 (95% carried blaCTX-M), with the majority blaCTX-M-15. Clade C1 was associated with blaCTX-M-14 and blaCTX-M-27, whereas blaCTX-M-15 predominated in clade C2. Plasmid-mediated AmpC genes (mainly blaCMY-2) were frequent (17.1%) but were more common in non-ST131 (P < 0.001) isolates from Singapore and Brisbane. Two strains carried both blaCMY-2 and blaCTX-M. The majority of plasmid replicon types were IncF. In a prospective collection of 3GC-R E. coli causing BSI, community-associated Clade C1/C2 ST131 predominate in association with blaCTX-M ESBLs, although a significant proportion of non-ST131 strains carried blaCMY-2.

A unique case of bilateral hydronephrosis caused by a fecalith.

Key Clinical MessageThis is a unique case that signifies the importance to look beyond the genitourinary system for causes of hydronephrosis. In addition, we outline the manner in which a fecalith should be addressed.