Stevens, Ryan W.

Abstract This publication represents the first part of an update to the clinical practice guideline on the diagnosis and management of group A streptococcal (Streptococcus pyogenes or GAS) pharyngitis, developed by the Infectious Diseases Society of America (IDSA). Diagnosis of GAS pharyngitis by clinician judgment alone is unreliable, and unselective testing incurs cost and inconvenience for individuals at low risk of having GAS infection. Clinical scoring systems have been used to quantify the probability of a positive GAS throat culture based on standardized criteria such as the presence of fever; tonsillar enlargement or exudate; tender and enlarged anterior cervical lymph nodes; and the absence of cough. The goal of this article is to determine whether a scoring system should be used to decide which patients should have a diagnostic test performed by rapid antigen detection test, molecular methods, and/or throat culture. We performed a systematic review of randomized and nonrandomized studies that compared the use of a clinical scoring system to clinician judgment alone in predicting the outcome of a throat culture. Evidence from studies in children and adults suggests the diagnostic accuracy of a clinical scoring system is comparable to or slightly higher than clinician judgment alone. However, the studies are limited due to small size, lack of uniformity in outcome measures, and incomplete data. The consensus of the panel is that the balance of benefits and harms favors use of a clinical scoring system as part of the evaluation of patients with sore throat. The principal utility of using a scoring system is to identify patients with low probability of GAS pharyngitis and to reduce unnecessary testing.

Abstract Background Posaconazole immediate release (IR) suspension is the standard product for enteral feeding tube (EFT) administration but has erratic pharmacokinetic behaviour, often resulting in subtherapeutic concentrations. Limited evidence suggests that posaconazole oral delayed-release (DR) tablets may be crushed. Methods This was a retrospective cohort study of hospitalized adults who received EFT administration of posaconazole IR suspension or crushed DR tablets between 2018 and 2024. Patients were eligible if they had at least one serum drug concentration drawn ≥5 days after posaconazole initiation. The primary outcome was attainment of therapeutic drug concentrations. Secondary outcomes included time to therapeutic serum concentration, adverse drug events, and frequency of occluded EFT. Results Of the included patients, 48 received IR suspension and 100 received DR tablets. Baseline characteristics and severity of illnesses were well balanced. Among IR suspension and crushed DR tablet recipients, 39% and 80% achieved therapeutic concentrations, respectively (P = 0.002). After adjusting for age, sex, BMI, drug interactions, posaconazole indication and malabsorptive conditions, crushed DR tablets were significantly more likely than IR suspension to achieve therapeutic posaconazole concentrations within 30 days (HR 5.22, 95% CI 2.35–11.61). Occluded EFTs were more frequent among crushed DR tablet recipients (27% versus 10%, P = 0.022), while no differences were observed in the occurrence of hepatotoxicity or hypokalaemia. Conclusions With EFT administration, crushed posaconazole DR tablets were associated with a greater likelihood of achieving therapeutic concentrations compared with IR suspension. The optimal technique for administering crushed DR tablets to prevent EFT complications warrants investigation.

This study aimed to determine if extended infusion (EI; over > 3 hr) beta-lactam therapy increased IV access requirements compared with traditional dosing (TD; over 30 min). Eighty-six adult ICU patients treated with TD anti-pseudomonal beta-lactams who underwent therapeutic drug monitoring (TDM) were included. Patients who transitioned from TD to EI after TDM (EI group) were matched 1:1 to patients who remained on TD. In the primary analysis, the median (interquartile range) total number of lumens in the 24 hours before TDM compared with the 48 hours after TDM were similar between groups (pre: TD 3 [2–5] vs. EI 4 [3–5]; p = 0.22 and post: TD 3 [2–4] vs. EI 4 [3–5]; p = 0.05). Delivery of beta-lactams via EI was not associated with a need for more IV access. Practical challenges such as access should not limit use of EI beta-lactams when indicated.

Abstract Background We investigated the relationship between cumulative, historical antibiotic therapy and the presence of ceftriaxone-resistant (CRO-R) Enterobacterales bloodstream infections (BSI) from urinary sources. Methods Adult patients established with primary care at Mayo Clinic with a first episode of monomicrobial Escherichia coli, Klebsiella pneumoniae, Klebsiella oxytoca, or Proteus mirabilis BSI from a urinary source from May 2019 to May 2023 were included. Antibiotic therapy over the year prior to BSI was quantified as days of therapy (DOT), cumulative modified Antibiotic Spectrum Index (mASI), and cumulative Days of Antibiotic Spectrum Coverage (DASC) using prescription data. Patients with CRO-R urinary pathogens prior to antibiotic therapy assessment were excluded. Results In total, 721 adults had monomicrobial gram-negative BSI, including 70 patients (9.7%) with a CRO-R pathogen and 651 patients (90.3%) with a ceftriaxone-susceptible (CRO-S) pathogen. In the 12 months prior to BSI, levels of antibiotic DOT, mASI, and DASC were significantly greater among patients with CRO-R BSI than CRO-S BSI (P < .001). The median time from blood culture collection to appropriate antibiotic therapy was significantly longer in the CRO-R group (24 hours, interquartile range [IQR] 16–48) than the CRO-S group (1 hour, IQR 0–2) (P < .001). Increasing cumulative antibiotic therapy prior to BSI, as quantified by the mASI, was significantly associated with increased risk of 1-year CDI after BSI (P = .027). Conclusions Patients with first episode CRO-R Enterobacterales BSI had significantly greater prior antibiotic exposure than patients with CRO-S BSI and experienced significant delay of appropriate therapy. Routine quantitation and reporting of prior antibiotic therapy may improve empiric prescribing.

Abstract Objectives To compare the efficacy and safety of antibiotic lock therapy (ALT) versus catheter removal in managing central vascular catheter–associated bloodstream infection (CVC-BSI). Methods We conducted a single-centre, retrospective cohort study of adult patients treated with ALT or catheter removal for management of CVC-BSI between 2018 and 2022. The primary outcome was a composite of 90 day microbiological relapse or recurrent BSI. Secondary outcomes included 30 day mortality, CVC-associated complications and Clostridioides difficile infection (CDI). Logistic regression with propensity score-adjustment was used to evaluate differences in outcomes and identify predictors of relapse. Results During the study period, 106 participants received ALT and 181 underwent catheter removal. Patients treated with ALT received shorter courses of systemic antimicrobials (11 versus 14 days; P < 0.001) and had shorter hospital stays (4 versus 10 days; P < 0.001). Median duration of catheter salvage in patients receiving ALT was 28 days (IQR 7–80). Primary composite outcome was similar between both groups, but ALT was associated with a significantly higher risk of microbiological relapse within 90 days (20% versus 7%; adjusted odds ratio 3.93, 95% CI 1.64–9.40; P = 0.002). No significant difference in 30 day mortality, CVC-related complications or CDI was observed. CoNS BSI was an independent predictor of microbiological relapse in patients treated with ALT (OR 2.28; P = 0.05). Conclusions Although ALT offers a non-invasive catheter salvage strategy, its association with higher relapse rates, particularly in CoNS BSI, suggests catheter removal should remain the preferred approach when feasible. ALT could be considered a short-term catheter salvage strategy for pathogens with low virulence when used with close surveillance.

Abstract Objective: Patients with Opioid Use Disorder (OUD) are prone to Multidrug-Resistant Organism (MDRO) colonization and infections, thus at risk for worse outcomes during critical illness. Understanding the prevalence and predictors of MDRO infections is essential to optimize interventions and treatments. Design: Retrospective cohort study. Methods: The study evaluated the prevalence of MDRO isolation among adults with OUD admitted to an intensive care unit (ICU) between January 1, 2018, and July 31, 2023. It included adults admitted to an ICU with bacterial infections and positive cultures obtained within 48 hours of admission. Demographics, clinical traits, and MDRO isolation rates were analyzed using descriptive statistics, univariate methods, and Least Absolute Shrinkage and Selection Operator (LASSO) regression. Results: MDRO isolation occurred in 178 of 790 patients (22.5%), with methicillin-resistant Staphylococcus aureus as the most frequently isolated organism. LASSO regression identified housing insecurity (OR: 1.79, 95% CI 1.09–2.93, P = .022), no receipt of medications for OUD treatment (OR: 1.56, 95% CI 1.06–2.29, P = .023), positive hepatitis C virus (HCV) status (OR: 2.19, 95% CI 1.19–4.03, P = .012), and intravenous antibiotic use in the prior 90 days (OR: 1.04 per 24 h, 95% CI 1.01–1.07, P = .007) as significant predictors of MDRO isolation. Conclusions: The study highlights a high prevalence of MDRO isolation in critically ill OUD patients admitted for infection-related issues with positive cultures obtained within 48 hours of admission, influenced by factors like housing insecurity, no receipt of medications for OUD treatment, HCV status, and prior antibiotic use.

Abstract Objective: To retrospectively observe procalcitonin (PCT) and antibiotic ordering practices in patients hospitalized with community-acquired pneumonia (CAP). Design: Retrospective, exact matched, multicenter cohort study from October 1, 2018 – March 31, 2023. Setting: All hospitals across the Mayo Clinic Enterprise. Participants: Adult patients with CAP, identified using pneumonia diagnosis codes and receipt of systemic antibiotics with an indication of “respiratory tract infection” within 48 hours of hospitalization. Methods: PCT testing within the first 7 days of hospitalization was compared to non-PCT care (nPCT). The primary outcomes were treatment duration, antibiotic days of therapy (DOT), and length of stay (LOS). Results: 15364 patients met inclusion criteria. PCT testing occurred in 42.4% (6515/15364) of encounters, totaling 8214 PCT results. 12880 unique patient encounters were matched 1:1, 6440 in each group. Treatment duration was longer in the PCT group compared to the nPCT group (5.1 vs 4.6 days, respectively, P < 0.001). Patients in the PCT group also received more DOT (8.6 vs 7.6 DOT, P < 0.001) and had a longer LOS (6.8 vs 5.9 days, P < 0.001), respectively. There was no difference in 30-day all-cause mortality or C. difficile infection between groups. In a sensitivity analysis of nPCT patients compared to those with a peak value <0.25 ng/mL (i.e. normal result) there was no difference in treatment duration (4.6 days nPCT vs 4.7 days normal PCT, P = 0.104) or LOS (5.9 days nPCT vs 6.0 days normal PCT, P = 0.134). Conclusion: PCT testing in patients hospitalized with CAP was not associated with reduced antimicrobial utilization, LOS, or 30-day all-cause mortality.

Abstract Reducing antimicrobial exposure by limiting the duration of therapy is an effective antimicrobial stewardship strategy. In this article, we describe the impact of modification of the electronic health record to remove default durations of therapy on ambulatory antibiotic prescriptions issued from emergency departments in a large, multicenter health system.

Abstract Background The opioid crisis and the increasing prevalence of multi-drug resistant organism (MDRO) infections pose a threat to public health. Opioid Use Disorder (OUD) patient are prone to MDRO colonization and infections, thus potentially leading to adverse outcomes during periods of critical illness. Understanding the prevalence and predictors of MDRO infections within this vulnerable population is critical to improving patient outcomes by optimizing interventions and treatment plans. Methods We conducted a retrospective, multicenter, cohort study to evaluate the prevalence of MDRO isolation among adults with OUD admitted to an intensive care unit (ICU) with an infection across four Mayo Clinic regions. Patients were classified to the MDRO cohort if an MDRO was isolated from standard cultures or rapid diagnostic testing within 48 hours of admission. We utilized descriptive statistics, univariate and multivariate least absolute shrinkage and selection operator (LASSO) regression analysis including random effect to account for site variability, to analyze demographic data, clinical characteristics, and outcomes. Results 790 critically ill adult OUD patients with infection-related admission were included in the study cohort. The prevalence of MDRO isolation was 22.5% (n=178), with MRSA being the predominant isolated MDRO. In LASSO regression analyses, we identified homelessness (OR: 1.79, p = 0.022), no Medications for OUD (MOUD) treatment (OR: 1.56, p=0.023), and positive Hepatitis C Virus (HCV) status (OR: 2.19, p = 0.012) as significant predictors for isolation of an MDRO. Intravenous (IV) antibiotic use in the preceding 90 days was also positively associated (OR: 1.04 per 24 hours, p = 0.007), alongside mental health disorders (OR: 2.03, p &lt; 0.001) and diabetes (OR: 1.54, p = 0.023). Conclusion The high prevalence of MDRO isolation in critically ill OUD patients with infection is associated with complex social and clinical factors. Disclosures All Authors: No reported disclosures