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A novel Bayesian method was developed to interpret serum vancomycin concentrations (SVCs) following the administration of one or more vancomycin doses with potential varying doses and intervals based on superposition principles. The method was evaluated using retrospective data from 442 subjects from three hospitals.

Purpose Creatinine-based estimates of glomerular filtration rate (GFR) have been the standard for classifying kidney function and guiding drug dosing for over 5 decades. There have been many efforts to compare and improve different methods to estimate GFR. The National Kidney Foundation recently updated the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equations without race for creatinine (CKD-EPIcr_R) and creatinine and cystatin C (CKD-EPIcr-cys_R), and the 2012 CKD-EPI equation based on cystatin C (CKD-EPIcys) remains. The focus of this review is to highlight the importance of muscle atrophy as a cause for overestimation of GFR when using creatinine-based methods. Summary Patients with liver disease, protein malnutrition, inactivity, denervation, or extensive weight loss may exhibit markedly lower creatinine excretion and serum creatinine concentration, leading to overestimation of GFR or creatinine clearance when using the Cockcroft-Gault equation or CKD-EPIcr (deindexed). In some cases, estimated GFR appears to exceed the physiological normal range (eg, >150 mL/min/1.73 m2). Use of cystatin C is recommended when low muscle mass is suspected. One would expect discordance between the estimates such that CKD-EPIcys < CKD-EPIcr-cys < CKD-EPIcr ≈ Cockcroft-Gault creatinine clearance. Clinical evaluation can then occur to determine which estimate is likely accurate and should be used for drug dosing. Conclusion In the setting of significant muscle atrophy and stable serum creatinine levels, use of cystatin C is recommended, and the resulting estimate can be used to calibrate interpretation of future serum creatinine measurements.

Purpose Prior to the 2020 release of a joint consensus guideline on monitoring of vancomycin therapy for serious methicillin-resistant Staphylococcus aureus (MRSA) infections, clinicians had escalated vancomycin doses for 2 decades while targeting trough concentrations of 15 to 20 µg/mL, leading to an increased frequency of nephrotoxicity. For MRSA infections, the 2020 guideline recommends adjusting doses to achieve a 24-hour area under the concentration-time curve (AUC) of 400 to 600 µg · h/mL; however, monitoring of trough concentrations has been entrenched for 3 decades. Calculating dose regimens based on AUC will require obtaining an increased number of vancomycin serum concentrations and, possibly, advanced software. The aim of this investigation was to determine the relationship between AUC and trough concentration and the influence of dosing regimen on goal achievement. Methods The relationship between trough concentration and AUC was explored through derivation of an equation based on a 1-compartment model and simulations. Results 24-hour AUC is related to dosing interval divided by half-life in a nonlinear fashion. The target trough concentration can be individualized to achieve a desired AUC range, and limiting use of large doses (>15-20 mg/kg) can protect against excessive 24-hour AUC with trough-only monitoring. Conclusion After initially determining pharmacokinetic parameters, subsequent monitoring of AUC can be accomplished using trough concentrations only. Trough concentration may be used as a surrogate for AUC, although the acceptable target trough concentration will vary depending on dosing interval and elimination rate constant. This work included development of an AUC-trough equation to establish a patient-specific target for steady-state trough concentration.

The confounding effects of next-generation sequencing (NGS) noise on detection of low frequency circulating tumor DNA (ctDNA) without a priori knowledge of solid tumor mutations has limited the applications of circulating cell-free DNA (ccfDNA) in clinical oncology. Here, we use a 118 gene panel and leverage ccfDNA technical replicates to eliminate NGS-associated errors while also enhancing detection of ctDNA from pancreatic ductal adenocarcinomas (PDACs). Pre-operative ccfDNA and tumor DNA were acquired from 14 patients with PDAC (78.6% stage II-III). Post-operative ccfDNA was also collected from 11 of the patients within 100 days of surgery. ctDNA detection was restricted to variants corresponding to pathogenic mutations in PDAC present in both replicates. PDAC-associated pathogenic mutations were detected in pre-operative ccfDNA in four genes (KRAS, TP53, SMAD4, ALK) from five patients. Of the nine ctDNA variants detected (variant allele frequency: 0.08%-1.59%), five had a corresponding mutation in tumor DNA. Pre-operative detection of ctDNA was associated with shorter survival (312 vs. 826 days; χ 2 =5.4, P = 0.021). Guiding ctDNA detection in pre-operative ccfDNA based on mutations present in tumor DNA yielded a similar survival analysis. Detection of ctDNA in the post-operative ccfDNA with or without tumor-informed guidance was not associated with outcomes. Therefore, the detection of PDAC-derived ctDNA during a broad and untargeted survey of ccfDNA with NGS may be a valuable, non-invasive, prognostic biomarker to integrate into the clinical assessment and management of patients prior to surgery.

Urothelial carcinoma (UC) presents most frequently as bladder cancer and is the most common cancer of the urinary system in the United States. UC relapse and progression are common and impose a significant negative impact on the lives of patients and healthcare resources. To elucidate the biological mechanisms of UC and find novel biomarkers, we analyzed the clinical and genomic data in the Oncology Research Information Exchange Network (ORIEN). We conducted gene-based and gene-set based association tests on rare germline variants comparing the exome sequencing of 336 UC patients and genome sequencing of 366 healthy controls (42 unrelated individuals from the Centre d'Etudes du Polymorphisme Humain [CEPH] families and 324 from the University of Utah Heritage 1000 [H1K] Projects). The analysis of loss-of-function (LoF) variants revealed that the forkhead box (FOX) J2 gene set was significantly associated with UC at the genome-wide level (Bonferroni-corrected p-value=0.01). Genes in this gene set contain a motif that matches the FOXJ2 transcription factor binding site. Firth-penalized Cox proportional hazard regression on overall survival identified LoF variants in genes down-regulated in naive CD8 T cells to be associated with worse prognosis (Bonferroni-corrected p-value=0.032, hazard ratio=28.2, and 95% confidence interval 6.66 to 119.0). In exome sequencing of tumor tissues, we searched for driver genes and pathways by testing for higher variant allelic fractions than the genome average. The tests yielded eleven genes with genome-wide significance (Table 1). By gene set analysis using the MSigDB Hallmark database, significant pathways included the P53 pathway (p Table 1. Genes with high allelic fractions Gene P-value Number of Variants TP53 Citation Format: Bing-Jian Feng, Wendy Kohlmann, David A. Nix, Aaron Atkinson, Kenneth M. Boucher, Courtney Carroll, Jill Kolesar, Eric A. Singer, Stephen B. Edge, Kamal Sahu, Alejandro Sanchez, Mikaela Larson, Michelle L. Churchman, Laura Graham, John D. Carpten, Yousef Zakharia, Lindsey Byrne, Rohit K. Jain, Kenneth G. Nepple, Ahmad Shabsigh, Jad Chahoud, Sumati Gupta. Germline and somatic genomic profiling of urothelial carcinoma. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6074.

Objective: This article critically evaluates common Pseudomonas aeruginosa resistance mechanisms and the properties newer β-lactam antimicrobials possess to evade these mechanisms. Data Sources: An extensive PubMed, Google Scholar, and ClinicalTrials.gov search was conducted (January 1995 to July 2020) to identify relevant literature on epidemiology, resistance mechanisms, antipseudomonal agents, newer β-lactam agents, and clinical data available pertaining to P aeruginosa. Study Selection and Data Extraction: Relevant published articles and package inserts were reviewed for inclusion. Data Synthesis: Therapeutic options to treat P aeruginosa infections are limited because of its intrinsic and acquired resistance mechanisms. The goal was to identify advances with newer β-lactams and characterize improvements in therapeutic potential for P aeruginosa infections. Relevance to Patient Care and Clinical Practice: Multidrug-resistant (MDR) P aeruginosa isolates are increasingly encountered from a variety of infections. This review highlights potential activity gains of newer β-lactam antibacterial drugs and the current clinical data to support their use. Pharmacists will be asked to recommend or evaluate the use of these agents and need to be aware of information specific to P aeruginosa, which differs from experience derived from Enterobacterales infections. Conclusions: Newer agents, including ceftazidime-avibactam, ceftolozane-tazobactam, imipenem-relebactam, and cefiderocol, are useful for the treatment of MDR P aeruginosa infections. These agents offer improved efficacy and less toxicity compared with aminoglycosides and polymyxins and can be used for pathogens that are resistant to first-line antipseudomonal β-lactams. Selection of one agent over another should consider availability, turnaround of susceptibility testing, and product cost. Efficacy data specific for pseudomonal infections are limited, and there are no direct comparisons between the newer agents.

Objectives: To discuss the evidence and caveats associated with estimated and measured creatinine clearance (eClCr and mClCr) and glomerular filtration rate (eGFR and mGFR) assessments of kidney function in patients with more extreme forms of obesity. Data Sources: PubMed (1976 to mid-May 2020) was used, with bibliographies of retrieved articles searched for additional articles. Study Selection and Data Extraction: Articles using gold standard mGFR to evaluate eClCr, mClCr, and eGFR assessments of kidney function in patients with more extreme forms of obesity were included. Data Synthesis: The overestimation of GFR by mClCr is well established, but mClCr is an alternative to mGFR assessments for determining medication dosing in patients with extremes of body size or muscle mass, or in patients receiving narrow therapeutic index medications when eGFR is likely to be inaccurate. The vast majority of studies comparing eGFR assessments with gold standard indicators of kidney function were attempts to validate eGFR equations for diagnosing and staging chronic kidney disease (CKD). Relevance to Patient Care and Clinical Practice: For dosing medications in patients with stable kidney function and extreme obesity, a deindexed 4-variable Modification of Diet in Renal Disease or CKD Epidemiology Collaboration equation is an alternative to Cockcroft-Gault. Consistent use of the same equation by provider and between providers within any given setting is of paramount importance. Conclusions: In patients with extreme obesity and stable kidney function, eClCr or eGFR using deindexed values provides estimates of function for dosing adjustments of medications with elimination by the kidneys, but more research is needed with respect to the best size descriptor to use with estimating equations.

Personal genomic educational testing (PGET) has been suggested as a strategy to improve student learning for pharmacogenomics (PGx), but no randomized studies have evaluated PGET’s educational benefit. We investigated the effect of PGET on student knowledge, comfort, and attitudes related to PGx in a nonblinded, randomized controlled trial. Consenting participants were randomized to receive PGET or no PGET (NPGET) during 4 subsequent years of a PGx course. All participants completed a pre‐survey and post‐survey designed to assess (1) PGx knowledge, (2) comfort with PGx patient education and clinical skills, and (3) attitudes toward PGx. Instructors were blinded to PGET assignment. The Wilcoxon Rank Sum test was used to compare pre‐survey and post‐survey PGx knowledge, comfort, and attitudes. No differences in baseline characteristics were observed between PGET (n = 117) and NPGET (n = 116) participants. Among all participants, significant improvement was observed in PGx knowledge (mean 57% vs. 39% correct responses; p

Background There are conflicting recommendations between organizations regarding aminoglycoside use for the prophylaxis of type III open fractures. Study question To compare cefazolin monotherapy versus cefazolin plus aminoglycoside therapy for prophylaxis of type III open fractures in trauma patients. Study design This was a multicenter, retrospective, cohort study conducted in 3 academic medical centers in the United States. Consecutive adult trauma patients with type III open fractures between January 2014 and September 2016 were included. Patients were divided into 2 groups: (1) cefazolin monotherapy versus (2) cefazolin plus aminoglycoside. Measures and outcomes The primary outcome measure was the occurrence of infection at the open fracture site. The secondary outcome measure was the occurrence of acute kidney injury. Results There were 134 patients included in the study cohort. Of these, 39 received cefazolin monotherapy and 95 received cefazolin plus aminoglycoside. Overall, the mean age was 39 ± 15 years, 105 (78%) were male, and the most common fracture location was tibia/fibula (n = 74, 56%). Infection at the open fracture site occurred in 6 of 39 patients (15%) in the cefazolin monotherapy group and 15 of 95 patients (16%) in the cefazolin plus aminoglycoside group (P = 1.000). Acute kidney injury occurred in 0 of 39 (0%) in the cefazolin monotherapy group and 1 of 95 (1%) in the cefazolin plus aminoglycoside group (P = 1.000). Conclusions Cefazolin monotherapy may be appropriate for antimicrobial prophylaxis of type III open fractures in trauma patients.

Purpose: We aimed to assess factors associated with therapy failure in patients with community-acquired pneumonia in the intensive care unit (ICU). Methods: Electronic charts of patients with International Classification of Diseases, Ninth Revision, codes of pneumonia who were admitted to the ICU at a tertiary academic medical center in Southern Arizona were reviewed. Results: Antipseudomonal coverage and anti-methicillin-resistant Staphylococcus aureus (MRSA) coverage were often prescribed (58.4% and 54.1%, respectively). Antipseudomonal coverage was rarely necessary as pseudomonal pneumonia was found in only one case (0.9%). Antipseudomonal and anti-MRSA coverage was not associated with improved outcomes. Conclusion: Overprescription of antibiotics in this population remains a significant problem. More work is needed to further limit unnecessary antibiotic use.

Alpacas residing in the region endemic for Coccidioides spp. are susceptible to serious, disseminated coccidioidomycosis that may result in death. There is currently no oral antifungal dose recommendation for this species. We used a steady-state study design to assess the pharmacokinetics of oral generic fluconazole in alpacas dosed q 24 h for 14 days. Cohorts of 2-3 animals received fluconazole from 6 to 15 mg/kg/day, and pharmacokinetic analysis was performed after each group of animals in order to make dose adjustments for the next group. The final three animals were used as confirmation of our dose recommendation. The median Tmax was 7 h, and the median Cmax was 1.25 µg/ml per mg/kg dose. The mean dose-normalized 24-h AUC was 41.7 µg h/ml per mg/kg dose (CV = 72%). Based on these results, we recommend alpacas receive a starting dose of oral fluconazole at 10-15 mg/kg/day based on the fluconazole AUC in humans (313-625 µg h/ml). Testing to ascertain putative therapeutic plasma concentrations and monitoring of serum transaminases should be performed.

Objectives: To discuss methods for the assessment of creatinine clearance (Clcr) when serum creatinine (SCr) is not at steady state in order to estimate kidney function and apply the estimate to kidney function staging for clinical assessment or drug dosing. Data Sources: A PubMed search was conducted from 1976 to mid-January 2021 with other articles identified through review of bibliographies of retrieved articles and citations in Scopus. Study Selection and Data Extraction: Articles assessing Clcr under non–steady-state conditions and studies evaluating predictive equations were selected. Data Synthesis: When SCr is systematically changing (ie, trending up or down), kinetic methods to estimate Clcr are appropriate. Estimates from kinetic methods should be individual based and not indexed to body surface area, and careful monitoring is required to confirm predictions as the situation evolves. Standard methods intended for steady-state conditions should not be used to estimate Clcr in patients with unstable SCr. Relevance to Patient Care and Clinical Practice: Creatinine continues to be a monitoring parameter of choice and is an important variable in all the commonly used equations for estimating Clcr and most important for estimating glomerular filtration rate. However, standard methods of estimating Clcr for medication dosing are not accurate under non–steady-state conditions. Conclusion: The methods for kinetic clearance estimation and standards methods for clearance estimation, such as the Cockcroft-Gault equation, are mutually exclusive. There are no benefits of using the kinetic method in patients with stable SCr concentrations, and standard equations are not appropriate with unstable SCr concentrations.

Background Coccidioidomycosis, ie, Valley fever, is an important fungal infection in the Southwest, with half to two thirds of all cases occurring in Arizona. This endemic respiratory disease can range from primary uncomplicated pneumonia to disseminated infection such as meningitis with chronic pulmonary complications. Valley fever diagnoses have risen over recent years and cause substantial morbidity and economic burden in Arizona. Methods We estimated the lifetime cost-of-illness associated with all cases of Valley fever diagnosed in 2019 in Arizona. Natural history of the disease was determined from literature and expert opinion and assigned costs from national data sources to determine lifetime direct and indirect costs (work loss). Results Total lifetime costs of $736 million were estimated for the 10 359 cases of Valley fever diagnosed in Arizona in 2019. Direct costs of $671 million accounted for over 90% of expenditures, with $65 million in indirect costs. Disseminated infection produces the highest economic burden at $1.26 million direct and $137 400 indirect costs per person. The lowest Valley fever lifetime costs were for cases of primary uncomplicated pneumonia with $23 200 in direct costs and $1300 in lost wages. The average lifetime direct costs across all Valley fever manifestations are $64 800 per person diagnosed in Arizona in 2019 and $6300 for indirect costs. Conclusions Valley fever is responsible for substantial economic burden in Arizona. Our estimates underscore the value of supporting research into developing more rapid diagnostic tests, better therapies, and ultimately a preventative vaccine to address this important public health problem in Arizona., Valley fever is an important disease in Arizona causing substantial morbidity and cost. We estimated lifetime costs for newly diagnosed cases of Valley fever in Arizona in 2019 at $671 million in direct costs and $65 million in indirect costs.

This article critically evaluates commonAn extensive PubMed, Google Scholar, and ClinicalTrials.gov search was conducted (January 1995 to July 2020) to identify relevant literature on epidemiology, resistance mechanisms, antipseudomonal agents, newer β-lactam agents, and clinical data available pertaining toRelevant published articles and package inserts were reviewed for inclusion.Therapeutic options to treatMultidrug-resistant (MDR)Newer agents, including ceftazidime-avibactam, ceftolozane-tazobactam, imipenem-relebactam, and cefiderocol, are useful for the treatment of MDR

In this prospective study, we examined the pharmacokinetics of 1 and 2 mg/kg liposomal amphotericin B in 16 morbidly obese individuals (104–177 kg). Body size had no effect on clearance. We recommend a fixed dose in patients ≥100 kg (ie, 300 or 500 mg rather than the current dose of 3 and 5 mg/kg, respectively). Clinical Trials Registration NCT02320604.

Challenges with distinguishing circulating tumor DNA (ctDNA) from next-generation sequencing (NGS) artifacts limits variant searches to established solid tumor mutations. Here we show early and random PCR errors are a principal source of NGS noise that persist despite duplex molecular barcoding, removal of artifacts due to clonal hematopoiesis of indeterminate potential, and suppression of patterned errors. We also demonstrate sample duplicates are necessary to eliminate the stochastic noise associated with NGS. Integration of sample duplicates into NGS analytics may broaden ctDNA applications by removing NGS-related errors that confound identification of true very low frequency variants during searches for ctDNA without a priori knowledge of specific mutations to target.

Crohn’s disease is a complex genetic trait characterized by chronic relapsing intestinal inflammation. Genome wide association studies (GWAS) have identified more than 170 loci associated with the disease, accounting for ∼14% of the disease variance. We hypothesized that rare genetic variation in GWAS positional candidates also contribute to disease pathogenesis. We performed targeted, massively-parallel sequencing of 101 genes in 205 children with Crohn’s disease, including 179 parent-child trios and 200 controls, both of European ancestry. We used the gene burden test implemented in VAAST and estimated effect sizes using logistic regression and meta-analyses. We identified three genes with nominally significant p-values: NOD2, RTKN2, and MGAT3. Only NOD2 was significant after correcting for multiple comparisons. We identified eight novel rare variants in NOD2 that are likely disease-associated. Incorporation of rare variation and compound heterozygosity nominally increased the proportion of variance explained from 0.074 to 0.089. We estimated the population attributable risk and total heritability of variation in NOD2 to be 32.9% and 3.4%, respectively, with 3.7% and 0.25% accounted for by rare putatively functional variants. Sequencing probands (as opposed to genotyping) to identify rare variants and incorporating phase by sequencing parents can recover a portion of the missing heritability of Crohn’s disease.

Background Siglec-8 is a CD33 subfamily cell-surface receptor selectively expressed on human eosinophils. After cytokine priming, Siglec-8 mAb or glycan ligand binding causes eosinophil apoptosis associated with reactive oxygen species (ROS) production. Most CD33-related Siglecs function as inhibitory receptors, but the ability of Siglec-8 to stimulate eosinophil ROS production and apoptosis suggests that Siglec-8 might instead function as an activating receptor. Objective We sought to determine the role of IL-5 priming and identify the signaling molecules involved in Siglec-8 function for human eosinophils. Methods We used an mAb and/or a multimeric synthetic sulfated sialoglycan ligand recognizing Siglec-8 in combination with integrin blocking antibodies, pharmacologic inhibitors, phosphoproteomics, and Western blot analysis to define the necessity of various proteins involved in Siglec-8 function for human eosinophils. Results Cytokine priming was required to elicit the unanticipated finding that Siglec-8 engagement promotes rapid β 2 -integrin–dependent eosinophil adhesion. Also novel was the finding that this adhesion was necessary for subsequent ROS production and apoptosis. Siglec-8–mediated ROS was generated through reduced nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activation because pretreatment of eosinophils with catalase (an extracellular superoxide scavenger) or NSC 23766 (a Rac GTPase inhibitor) completely inhibited Siglec-8–mediated eosinophil apoptosis. Finally, engagement of Siglec-8 on IL-5–primed eosinophils resulted in increased phosphorylation of Akt, p38, and c-Jun N-terminal kinase 1 that was also β 2 -integrin dependent; pharmacologic inhibition of these kinases completely prevented Siglec-8–mediated eosinophil apoptosis. Conclusions These data demonstrate that Siglec-8 functions uniquely as an activating receptor on IL-5–primed eosinophils through a novel pathway involving regulation of β 2 -integrin–dependent adhesion, NADPH oxidase, and a subset of protein kinases.

Background Fluconazole (fluc) is a common antifungal used at hospitals and is an important target for antimicrobial stewardship (AS). Fluc is also used for management of coccidioidomycosis (C). The objective of our study was to describe fluc prescribing patterns at two academic centers in Arizona. Methods We conducted a retrospective analysis of fluc usage in adult patients. One month from each quarter in a one-year period (November 2017-November 2018) was selected (4 months in total). All adult patients that received fluc at Hospital A and Hospital B in the selected months were identified. Patient demographic information and Charlson comorbidity index (CCI) to quantify the degree of comorbidity were collected. We then analyzed patients in the study by defining the fluc usage as directed towards C management or non-C management (e.g., candidiasis). In the C management group, we characterized the initial fluc dose during the patient’s course as directed for empiric, targeted, or prophylaxis treatment. Finally, we performed further analysis of the empiric C group. The study received IRB approval from our institution. Results During our study period, 1239 patients were included in the analysis. Patient information is shown in Table 1. Overall, most of the fluc usage was directed towards C management (63.5%, 787/1239). A significant amount of that usage was directed towards C prophylaxis at both Hospital A and B (67.4% (234/347) and 75% (330/440), respectively). In addition, fluc usage directed towards empiric C management was higher at Hospital A versus Hospital B (18.4% (64/347) versus 9.5% (42/440), respectively). Further patient data for the empiric C group is shown in Table 2. Conclusion We report the results of a descriptive study that demonstrate that 63.5% of fluc usage in adults at two academic medical centers in Arizona was directed for C management. In addition to traditional fluc targets for AS, our study highlights C prophylaxis in solid organ transplant recipients and empiric C management as AS targets in endemic regions. These targets are especially important due to the risk for selection of azole-resistant Candida species and invasive molds with increased antifungal exposure. Disclosures All Authors: No reported disclosures

Creatinine is an endogenous waste product resulting from the breakdown of creatine phosphate, a compound largely stored in skeletal muscle. The amount and rate of creatinine excretion (mg per 24 hours) are related to muscle mass; in fact, these measures have been used to estimate muscle mass.[1][1

To assess the severity of inflammation associated with diabetic foot infection (DFI), values of inflammatory markers such as white blood count (WBC), C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), and neutrophil to lymphocyte ratio (NLR) are often measured and tracked over time. It remains unclear if these markers can aid the clinician in the diagnosis and management of DFI, and ensure more rational use of antibiotics. Hospitalized adult patients (n = 379) with DFI were retrospectively assessed for abnormal inflammatory markers, correlation between values of inflammatory markers, and clinical diagnosis on initial admission and on last follow-up. At admission, WBC, ESR and NLR were each elevated in patients with osteomyelitis and only ESR was significantly elevated in patients with soft tissue infection only. Only WBC was significantly elevated in patients with osteomyelitis compared with uninfected diabetic feet on last follow-up. Considering the predictive performance of these inflammatory markers, they demonstrated excellent positive predictive value at admission, and excellent negative predictive value at the last follow-up visit. Moreover, the number of elevated markers was further associated with probability of infection both at admission and last follow-up.

Heme catabolism is an important biochemical process that many bacterial pathogens utilize to acquire iron. However, tetrapyrrole catabolites can be reactive and often require further processing for transport out of the cell or conversion to another useful cofactor. In previous work, we presented in vitro evidence of an anaerobic heme degradation pathway in Escherichia coli O157:H7. Consistent with reactions that have been reported for other radical S-adenosyl-L-methionine methyltransferases, ChuW transfers a methyl group to heme by a radical-mediated mechanism and catalyzes the β-scission of the porphyrin macrocycle. This facilitates iron release and the production of a new linear tetrapyrrole termed “anaerobilin”. In this work, we describe the structure and function of ChuY, an enzyme expressed downstream from chuW within the same heme utilization operon. ChuY is structurally similar to biliverdin reductase and forms a dimeric complex in solution that reduces anaerobilin to the product we have termed anaerorubin. Steady state analysis of ChuY exhibits kinetic cooperativity that is best explained by a random addition mechanism with a kinetically preferred path for initial reduced nicotinamide adenine dinucleotide phosphate binding.

Objectives The purpose of this study is to describe the clinical history leading up to and the outcomes after vaginal mesh removal surgery at an academic hospital. Methods A retrospective case series of patients who underwent vaginal mesh removal from 2008 to 2015 was conducted. Demographics, clinical history, physical examination, pre- and postoperative symptoms, and number and type of reoperations were abstracted. Results Between February 2008 and November 2015, 83 patients underwent vaginal mesh removal surgery at our hospital. The median time interval from initial mesh placement to removal was 58 months (range, 0.4-154 months). The most common preoperative symptoms were vaginal pain (n = 52, 62%), dyspareunia (n = 46, 55%), and pelvic pain (n = 42, 50%). Intraoperative complications were infrequent (n = 3, 4%). Of patients presenting for follow-up within 4 to 6 weeks postoperatively, the most common symptoms were urinary incontinence (n = 15, 28%), vaginal pain (n = 7, 13%), buttock pain (n = 5, 9%), and urinary tract infection (n = 5, 9%). There were no identifiable risk factors to predict which patients would have persistent postoperative symptoms or who would require more than 1 mesh removal surgery. After vaginal mesh removal, 29 patients (35%) required 1 or more reoperations, with 3 being the highest number of reoperations per patient. The total number of reoperations was 43, with a total of 63 individual procedures performed. Forty-four percent (n = 28) of the procedures were graft removals, 40% (n = 25) were pelvic organ prolapse surgeries (only native tissue repairs), and 16% (n = 10) were stress incontinence surgeries. More than 1 procedure was performed in 49% (n = 21) of the reoperations. Conclusions Vaginal mesh removal surgery is safe; however, some patients require more than 1 procedure, and the risk factors for reoperations are unclear.

Background: Implementing robust antimicrobial stewardship programs within long-term care facilities (LTCFs) presents unique challenges not typically seen in other healthcare settings. These facilities tend to care for older adults, rely on limited on-site clinician availability and experience higher-than-normal staff turnover. Many LTCFs lack the resources and expertise to track and analyze antibiotics usage. Through a collaborative effort between the Arizona Department of Health Services and the University of Arizona College of Pharmacy, support for carrying out stewardship activities was provided to these healthcare facilities. Our objective was to assess the viability of using pharmacy prescribing data to evaluate antibiotics usage among LTCFs throughout Arizona to assist in development of antimicrobial stewardship interventions. Methods: We invited interested LTCFs to participate in the development and enhancement of antimicrobial stewardship programs. We analyzed antibiotic prescribing data from November 2017 through November 2018 to assess the types and quantities of antibiotics prescribed. We worked with pharmacies to obtain a deidentified dataset that included unique patient identifiers, transaction (start) date, agent name, directions for use, route of administration, quantity dispensed, and stop dates. We estimated duration of treatment by assessing antibiotic starts using the number of transaction dates and unique patient identifiers for repeat prescriptions. Each agent was evaluated individually and assigned to an antibiotic category to better assess cumulative prescribing. Results: Through assistance from our community partners, we recruited 11 facilities to participate and worked with 5 servicing pharmacies to obtain a complete dataset for 6 LTCFs. For the facilities evaluated, there were a total of 4,654 antibiotic prescriptions. The most commonly prescribed antibiotic categories were fluroquinolones (24.3% of prescriptions) and oral β-lactams (17.8% of prescriptions). The third most commonly prescribed antibiotics were agents utilized against methicillin-resistant Staphylococcus aureus (MRSA) (13.7% of prescriptions). Antibiotic duration ranged from 1 to 304 days of therapy. Conclusions: Working directly with servicing pharmacies is an efficient way to obtain antibiotic prescribing data for LTCFs. During the 1-year period evaluated, antibiotic prescription rates varied between LTCFs. Despite numerous warnings, the fluroquinolone class continue to be among the most commonly prescribed antibiotics. Visualizing trends in LTCFs antibiotic data is an optimal way to develop and enhance antimicrobial stewardship programs in LTCFs. This fundamental information can help identify areas in which a facility can focus their stewardship efforts and provide a baseline for monitoring progress over time.Funding: NoneDisclosures: None

We surveyed urgent care centers (UCCs) in the state of Arizona to determine whether they offered the influenza vaccine during the 2016-2017 influenza season. Overall vaccine availability was 80.3% at these facilities. During this season, one-third of the UCCs offered influenza vaccination to children 6 months or older; approximately two-thirds offered influenza vaccination to children and young adults 16 years or older. This is the first study of influenza vaccine availability at UCCs.

Skin and soft-tissue infections (SSTIs) are commonly encountered by medical students, residents, and trainees. The Infectious Diseases Society of America (IDSA) has updated its recommendations regarding SSTI diagnosis and management in June 2014. We assessed knowledge, attitude, and practices toward diagnosis and management of SSTIs using an online survey. We disseminated the survey to medical students, residents, and attending physicians practicing in family and internal medicine department at a university-based hospital. A total of 103 surveys were completed out of 121 sent (85.1%) between July 2015 and March 2016. There were nine medical questions in the survey. The mean of correct answers was 4.5/9 ± 2.0. Medical knowledge correlated with the level of education (P < 0.001) but not with subspecialty (P = 0.97). Around 35% were familiar with the updated IDSA guidelines pertaining to SSTIs. The majority (85%) responded that the hospital staff would benefit from additional training and 75% agreed that more antibiotic stewardship education is needed. Our study shows that there are significant opportunities for development among students and physicians who encounter SSTIs.

Patient-Derived Xenografts (PDXs) are tumor-in-mouse models for cancer. PDX collections, such as those supported by the NCI PDXNet program, are powerful resources for preclinical therapeutic testing. However, variations in experimental design and analysis procedures have limited interpretability. To determine the robustness of PDX studies, the PDXNet tested temozolomide drug response for three pre-validated PDX models (sensitive, resistant, and intermediate) across four blinded PDX Development and Trial Centers (PDTCs) using independently selected SOPs. Each PDTC was able to correctly identify the sensitive, resistant, and intermediate models, and statistical evaluations were concordant across all groups. We also developed and benchmarked optimized PDX informatics pipelines, and these yielded robust assessments across xenograft biological replicates. These studies show that PDX drug responses and sequence results are reproducible across diverse experimental protocols. Here we share the range of experimental procedures that maintained robustness, as well as standardized cloud-based workflows for PDX exome-seq and RNA-Seq analysis and for evaluating growth.

HSUR2 is a viral non-coding RNA (ncRNA) that functions as a microRNA (miRNA) adaptor. HSUR2 inhibits apoptosis in infected cells by recruiting host miRNAs miR-142–3p and miR-16 to mRNAs encoding apoptotic factors. HSUR2’s target recognition mechanism is not understood. It is also unknown why HSUR2 utilizes miR-16 to downregulate only a subset of transcripts. We developed a general method for individual-nucleotide resolution RNA-RNA interaction identification by crosslinking and capture (iRICC) to identify sequences mediating interactions between HSUR2 and target mRNAs in vivo. Mutational analyses confirmed identified HSUR2-mRNA interactions and validated iRICC as a method that confidently determines sequences mediating RNA-RNA interactions in vivo. We show that HSUR2 does not display a ‘seed’ region to base-pair with most target mRNAs, but instead uses different regions to interact with different transcripts. We further demonstrate that this versatile mode of interaction via variable base-pairing provides HSUR2 with a mechanism for differential miRNA recruitment.

Muco-obstructive lung diseases (MOLDs), like cystic fibrosis and chronic obstructive pulmonary disease, affect a spectrum of subjects globally. In MOLDs, the airway mucus becomes hyperconcentrated, increasing osmotic and viscoelastic moduli and impairing mucus clearance. MOLD research requires relevant sources of healthy airway mucus for experimental manipulation and analysis. Mucus collected from endotracheal tubes (ETT) may represent such a source with benefits, e.g., in vivo production, over canonical sample types such as sputum or human bronchial epithelial (HBE) mucus. Ionic and biochemical compositions of ETT mucus from healthy human subjects were characterized and a stock of pooled ETT samples generated. Pooled ETT mucus exhibited concentration-dependent rheologic properties that agreed across spatial scales with reported individual ETT samples and HBE mucus. We suggest that the practical benefits compared with other sample types make ETT mucus potentially useful for MOLD research.

Our recent study demonstrated that the histone methyltransferase Smyd1 positively regulates cardiac metabolism through transcriptional control of PGC-1α, a key regulator of mitochondrial energetics. However, it is largely unknown whether Smyd1 plays a role in adaptive responses to metabolic stress in cardiomyocytes. Here, we hypothesized that Smyd1 is required for cell survival during metabolic stress through maintaining energetic balance. To address this hypothesis, neonatal rat ventricular myocytes (NRVMs) were cultured in glucose-free media for 24 hours and real-time quantitative PCR was performed. We found that Smyd1 and its downstream target PGC-1α were upregulated during glucose starvation, concurrent with the significant increase of mRNA levels of PPARα and CPT1b , the key regulators of fatty acid β-oxidation (all pSmyd1 knockdown (siSmyd1) prior to glucose starvation led to massive cell death, evidenced by the dissipation of MIMP and the uptake of the normally cell-impermeable indicator YO-PRO. To better understand the mechanism of siSmyd-NRVMs vulnerability to glucose starvation, we examined the expression of genes involved in metabolism and apoptosis at the early stage of glucose starvation (3 hr), when autophagy was activated as evidenced by upregulation of LC3 and FoxO1. We found that the upregulation of PGC-1α, PPARα, CPT1b, as well as LC3 and FoxO1, adaptively induced by glucose starvation in control NRVMs, were all abolished by Smyd1 knockdown, concomitant with a significant increase in gene expression of tumor necrosis factor receptor type 1-associated DEATH domain protein (Tradd). Moreover, RNA-seq analysis revealed that Smyd1 -knockdown per se led to upregulation of the genes involved in regulation of apoptosis and cell death (i.e. Tradd, Casp8, Ripk3, Smad1). These data suggest that upregulation of Smyd1 in response to metabolic stress is a critical adaptive mechanism for cell survival, operating via enhancement of fatty acid metabolism, activation of autophagy, and suppression of cell death signaling.

To evaluate the epidemiology, management, and outcomes associated with candiduria in intensive care unit (ICU) and medical ward (MW) patients. This was a retrospective cohort study conducted in a tertiary care academic medical center. Adult patients aged between 18 and 75 years who were admitted for at least 5 days with a urinary culture that grew a Candida species between July 2010 and June 2011 were included. Medical records were retrospectively reviewed. Laboratory data, urinary symptoms, risk factors for urinary and invasive candidiasis, treatment, and patient outcomes were collected and evaluated. Sixty-seven ICU and 65 MW patients met the inclusion criteria. ICU patients were more likely to have risk factors for invasive candidiasis and candiduria. Candida albicans and Candida glabrata were the most frequently identified urinary isolates. Antifungal therapy was commonly initiated despite rapid replacement or removal of urinary drainage devices and a lack of patient reported symptoms. Fluconazole was the most commonly used antifungal agent, followed by micafungin. Hospital length of stay did not vary significantly between the ICU and MW groups (P = 0.0628). All-cause mortality was higher in the ICU patients compared with that of the MW patients (22.4% vs. 3.1%, P = 0.0012). Differences exist between ICU and MW patients that develop candiduria with respect to risk factors, and outcomes. Antifungals, including fluconazole and micafungin, were often used inappropriately (ie, asymptomatic patients) in this patient cohort. Efforts to improve healthcare provider awareness of the contemporary recommendations to manage candiduria are necessary to improve patient care and antifungal use.