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Bayless, David

https://orcid.org/0009-0009-8837-1044

Mayo Clinic

Mayo Clinic

Citations 4

P-1935. Persistent Candidemia: Predictors and Outcomes in a Multicenter Matched Analysis
Bayless, David, Saleh, Omar M Abu, Bayless, David , McHugh, Jack , Saleh, Omar Abu , Vergidis, Paschalis , Challener, Douglas W.

Open Forum Infectious Diseases | January 12, 2026 | Volume: 13 | Issue: Supplement_1 | Pages: No page available

10.1093/ofid/ofaf695.2103 Get It

Abstract Background Persistent candidemia (PC) occurs in a minority of Candida bloodstream infections (BSIs) but is associated with increased morbidity. Comparative data on patient profile, species distribution and outcomes are limited.Table 1Clinical profile and outcomes of patients with persistent candidemia in the primary study cohort. ANC = absolute neutrophil count. SD = standard deviation.Table 2Comparative analysis of persistent candidemia and non-persistent candidemia cases. Methods All candidemia episodes at three academic medical centers (2018-2025) were reviewed. Persistence was defined as ≥72 hours of positive blood cultures after appropriate antifungal initiation. Each PC case was matched 1:2 to non-PC controls who survived ≥72 hours. Demographics, Charlson Comorbidity Index (CCI), Candida species distribution, and outcomes were used for comparative analysis. Continuous variables were summarized as median (interquartile range [IQR]) and compared with Wilcoxon rank-sum, while categorical data (n%) were analyzed by Fisher’s exact test (species by χ²), yielding odds ratios (ORs) with 95% confidence intervals (CIs). Two-tailed p < 0.05 denoted significance. Results Each PC case (n = 46) was matched 1:2 to non-PC controls (n = 92). Clinical profiles and outcomes of PC cases are presented in Table 1. Most PC patients (54.3%) had an immunocompromising condition, and non-urinary intra-abdominal sources were the most frequently suspected infection source (21/46; 45.7%). All but one of 46 PC cases had antibiotic exposure within the preceding 90 days. Comparative demographics and outcomes for PC cases and non-PC controls are displayed in Table 2. PC patients were younger (median 62 yr, IQR 45–69 vs 68 yr, 57–76; p = 0.01), more often female (59% vs 30%; OR 3.3, 95% CI 1.5–7.1; p = 0.002), and had higher comorbidity (CCI 5, IQR 3–8 vs 3, 1–4; p < 0.001). Species distribution differed (χ² p = 0.04), driven by C. guilliermondii over-representation in PC cases (9% vs 0%) (Figures 1 and 2). Hospital stay was longer in PC cases (median 36 d, 24–54 vs 16 d, 8–28; p < 0.001) and time from admission to first culture greater (12 d, 3–26 vs 3 d, 1–10; p = 0.003). 90-day mortality was 54.3% (25/46) in PC cases versus 31.5% (29/92) in controls (OR 2.57, 95% CI 1.17–5.71; p = 0.016). Conclusion In this 7-year multicenter study, there were significant differences in demographics, microbiology, and clinical outcomes between PC and non-PC cases, including higher short-term mortality rates with PC in univariate analysis. Disclosures Paschalis Vergidis, MD, MSc, Current Fungal Infection Reports: Honoraria|F2G: Grant/Research Support|Merck Manuals: Honoraria|Mundipharma: Grant/Research Support|Scynexis: Advisor/Consultant|Scynexis: Grant/Research Support
Clinical and microbiologic features of Achromobacter species: a 10-year, multicenter experience
Bayless, David , Dumais, Mitchell , McHugh, Jack , Ranganath, Nischal , Chesdachai, Supavit , Saleh, Omar M. Abu, Bayless, David R , Dumais, Mitchell G , McHugh, Jack , Chesdachai, Supavit , Abu Saleh, Omar M, Ranganath, Nischal , Fida, Madiha , Saleh, Omar Abu

Journal of Clinical Microbiology | September 19, 2025 | Volume: 63 | Issue: 10 | Pages: No page available

10.1128/jcm.00724-25 Get It

ABSTRACT Achromobacter species are Gram-negative bacilli that predominantly affect individuals with cystic fibrosis or those with immunocompromising conditions. Clinical and microbiologic data on Achromobacter species are limited due to the rarity of these organisms and challenges with species-level identification. We conducted a 10-year retrospective analysis (1 January 2013 to 14 March 2023) of all bloodstream and non-bloodstream Achromobacter isolates identified at three tertiary-care Mayo Clinic locations (Minnesota, Arizona, and Florida). Additionally, we examined clinical characteristics of adult patients with Achromobacter bloodstream isolates. A total of 1,598 Achromobacter isolates, encompassing 1,545 non-bloodstream isolates and 53 bloodstream isolates, were identified. The most frequently identified species was Achromobacter xylosoxidans , though species-level identification was not possible for many isolates. Among adult patients with Achromobacter bloodstream infection, the mean age was 58.3 years (standard deviation ± 16.7), 73.1% had a central venous catheter, and 59.6% were immunocompromised. All-cause mortality was 10.2% at 30 days and 18.4% at 90 days. Bloodstream isolates exhibited greater than 90% susceptibility to meropenem, piperacillin-tazobactam, and trimethoprim-sulfamethoxazole. The respiratory tract was the most common source of non-bloodstream isolates (57.5%). Non-bloodstream isolates showed high susceptibility to imipenem (94.6%), piperacillin-tazobactam (92.8%), trimethoprim-sulfamethoxazole (92.1%), and meropenem (87.5%) while demonstrating significant resistance to fluoroquinolones and aminoglycosides. Our findings support the use of piperacillin-tazobactam, carbapenems, or trimethoprim-sulfamethoxazole as initial therapy for Achromobacter infections. Further research is needed to better define the clinical and microbiologic characteristics of Achromobacter infections. IMPORTANCE Achromobacter is a rare but important genus of bacteria that tends to cause infection in those with cystic fibrosis, recurrent healthcare exposures, and/or an immunocompromising condition. There is limited data on the clinical profile of Achromobacter infections as well as optimal antibiotic selection for affected patients. We conducted a retrospective study to improve understanding of the microbiologic and clinical characteristics of Achromobacter . Our study consists of a 10-year survey of all Achromobacter isolates processed by three Mayo Clinic tertiary-care centers in Minnesota, Florida, and Arizona from 2013 to 2023. We report multiple findings, including the clinical characteristics of patients with Achromobacter bloodstream infection, the number of different Achromobacter species identified, and the sources of isolates not obtained from blood cultures. We additionally present antimicrobial susceptibility results for Achromobacter isolates. Our study provides guidance to clinicians treating Achromobacter infections and, it is hoped, will facilitate ongoing study of Achromobacter .
A 5-Year Epidemiological Study of Monomicrobial Enterococcal Bloodstream Infection in a Population-Based Cohort
Bayless, David , Baddour, Larry M. , Lahr, Brian D. , Hagan, Grace , Cao, Jenny Jia Ling , DeSimone, Daniel C. , Bayless, David R , Hagan, Grace A , Cao, Jenny J , Baddour, Larry , DeSimone, Daniel C

Open Forum Infectious Diseases | August 20, 2025 | Volume: 12 | Issue: 9 | Pages: No page available

10.1093/ofid/ofaf506 Get It

Abstract Background The incidence, epidemiology, and clinical characteristics of enterococcal bloodstream infection (BSI) have not previously been studied on a population-based level in the United States. Methods We utilized the Expanded Rochester Epidemiology Project medical records linkage system to conduct a contemporary 5-year, retrospective, population-based study of monomicrobial enterococcal (ME) BSI among adult residents of 8 counties in southeast Minnesota from January 1, 2018 to December 31, 2022. Results A total of 109 cases of ME-BSI were identified. The overall age- and sex-adjusted incidence rate was 6.7 per 100 000 person-years (95% confidence interval, 5.4–7.9). Multivariable analysis revealed that male sex (P < .001) and older age (P < .001) were each independently associated with increased incidence, whereas no temporal association was demonstrated (year effect, P = .475). The median age of incident cases was 76.8 years (interquartile range, 65.0–83.3). Urinary tract source was the most common presumed source (42.2%), and Enterococcus faecalis was the predominant (83.5%) pathogen. Overall, 14.4% of patients met modified Duke criteria for definite infective endocarditis. Cumulative mortality was 28.4% at 12 weeks and 43.1% at 1 year. Conclusions In this population-based study, ME-BSI was significantly associated with older age and male sex. There was a high rate of mortality at 12 weeks and 1 year, with ∼1 out of 7 cases complicated by definite infective endocarditis. These findings underscore the importance of ongoing investigation of this syndrome.
Tirzepatide-Associated Colonic Ischemia
Bayless, David , Singh, Jasraj, Sweetser, Seth , Park, Byoung Uk , Bayless, David R , Singh, Jasraj

ACG Case Reports Journal | November 6, 2024 | Volume: 11 | Issue: 11 | Pages: e01551

10.14309/crj.0000000000001551 Get It

ABSTRACT The use of the glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) receptor agonist tirzepatide has markedly increased for the treatment of weight loss and management of diabetes mellitus. Gastrointestinal adverse effects of GLP-1/GIP agonist therapy, including nausea, vomiting, and constipation, are common. We report a case of colonic ischemia in a 62-year-old woman which developed in association with the use of tirzepatide for weight loss. This report highlights a potential risk relationship between GLP-1/GIP agonist therapy and colonic ischemia and identifies risk factors that should be considered before prescribing tirzepatide.