Abstract Background Outpatient antibiotic stewardship programs (ASP) are recommended by the CDC and Joint Commission. We analyzed the impact of annual, focused syndrome-specific ASP interventions on trends in long-duration antibiotic prescribing (LDAP). Methods This was a retrospective, observational, multicenter cohort study from November 2020 through June 2025. All ambulatory encounters generating systemic antibiotic prescriptions within the healthcare enterprise were screened. Hospitalizations, emergency department visits, and infectious diseases encounters were excluded. Encounters generating ≥1 systemic antibiotic with >7 days duration were categorized as long-duration. Targeted departments (primary and urgent care) received direct intervention (eg, education, peer-comparison reporting, data tracking). LDAP was modeled over time by month and compared by diagnosis group (ASP-priority diagnoses vs nonpriority) and provider specialty department (ASP-targeted vs nontargeted) using linear regression models. Results Of 642 579 encounters included, 42.2% were long duration. LDAP in ASP-targeted departments dropped from 46.8% to 34.8% (difference −12 percentage points [pp]), whereas nontargeted departments dropped from 45.5% to 39.1% (difference −6.4 pp). The estimated annual LDAP decrease was 3.4 pp in targeted versus 2.4 pp in nontargeted departments (difference 1.0 pp, P = .009). Within targeted departments, significant LDAP decreases were seen both in priority and nonpriority diagnoses, whereas nontargeted departments showed no change in LDAP in priority diagnoses. In a sensitivity analysis of nonpriority diagnoses, ASP-targeted departments had a larger estimated annual decrease in LDAP versus nontargeted (difference 1.4 pp, P < .001). Conclusions Annual syndrome-specific ASP interventions correlated with improvements in LDAP, including outside of priority syndromes in targeted departments. LDAP is a viable metric for evaluating ambulatory ASPs.
Antibiotic Prophylaxis in Dermatologic Surgery: Advisory Statement 2025 (APDSAS 2025)
BACKGROUND Guidelines and evidence related to antibiotic prophylaxis in dermatologic surgery have evolved since the authors' previously published advisory statement. OBJECTIVE To provide an updated advisory statement on antibiotic prophylaxis in dermatologic surgery as guided by updated recommendations from the American Heart Association and the American Dental Association with the American Academy of Orthopaedic Surgeons guidelines. METHODS A structured literature review was performed. A multidisciplinary team of specialists from dermatologic surgery, infectious diseases, and pharmacy were convened to review up-to-date data and develop updated comprehensive evidence-based recommendations. RESULTS Consistent with the previous advisory statement, prophylactic antibiotics are recommended for patients with high-risk cardiac or prosthetic joint conditions, when the dermatologic surgical site is infected or if the procedure breaches the mucosa. Significant changes were made for prophylaxis of surgical site infection. Updated recommendations were made regarding antibiotic selection in penicillin-allergic patients and intraoperative use of intraincisional clindamycin in the local anesthetic. LIMITATIONS Reviewed data are predominantly limited to retrospective data. CONCLUSION Recommendations regarding antibiotic prophylaxis around dermatologic surgery are evolving as new data and practices are introduced. The 2025 advisory statement provides the latest recommendations for appropriate use of antibiotic prophylaxis in dermatologic surgery.
Long-term cellular and humoral responses to SARS-CoV-2 vaccinations in patients with solid malignancies undergoing chemotherapy
Background While SARS-CoV-2 vaccines are highly effective in healthy individuals, the magnitude and durability of humoral and cellular responses in patients with solid malignancies receiving chemotherapy remain understudied. Previous reports suggest that patients with cancer may not mount adequate immune response after SARS-CoV-2 vaccination. Additionally, most studies focused on humoral responses, while data regarding cellular immune responses are scarce. In this study, we evaluated humoral and cellular responses in patients with solid tumors receiving chemotherapy compared to healthy individuals up to one year after vaccinations. Methods Patients aged ≥18 who were willing to receive the SARS-CoV-2 vaccine were enrolled. Anti-SARS-CoV-2 immunoassays were used to detect antibodies against nucleocapsid and spike proteins. Human IFN-γ Fluorospot assay was used to determine antigen−specific T-cell responses. Data were compared between groups using Mann−Whitney test for continuous variables and Fisher’s exact test for categorical variables. Results A total of 67 subjects (47 patients with cancer and 20 healthy individuals) were included. 1–3 months following the second vaccine doses, 96% of patients with cancer and 100% of healthy individuals demonstrated a positive humoral response. While the positivity rate was not significantly different, patients with cancer had significantly lower spike IgG antibodies than healthy individuals. However, this difference diminished at 6 months when patients with cancer had increased antibodies compared to decreased antibodies in the healthy cohort and no difference was noticed at 12-month. Patients with cancer developed a similar antigen-specific T-cell response as healthy individuals at 1–3 months, 6 months and 12 months. There were no significant differences when comparing patients aged ≤ 55 years vs. >55 years, stages I-III vs. IV, single vs. multiple chemotherapy, and BNT162b2 vs. mRNA-1273 vaccines. There was a significant moderate correlation between neutralization and antibody levels at 12 months. However, despite patients with cancer having a significantly higher COVID risk score, there were no significant differences in COVID-19 infection and hospitalization between patients with cancer and healthy individuals. Conclusion Despite initial impaired antibody responses to SARS-CoV-2 vaccinations, patients with solid malignancies receiving chemotherapy effectively generated long-term cellular and humoral responses by 6 and 12 months, leading to similar infection and hospitalization rates compared to healthy individuals.
P-1867. Electronic Delivery of an OPAT Patient Education Video: Enhancing Accessibility and Clinician Satisfaction
Abstract Background Outpatient parenteral antimicrobial therapy (OPAT) has been shown to have numerous benefits including lower costs, increased patient satisfaction, and decreased healthcare associated infections. Patient education is a crucial part of the OPAT process, as lack of understanding may lead to adverse drug events, emergency department visits, or hospital re-admission. A baseline survey of OPAT clinicians at a large multi-state health system revealed low awareness of existing OPAT education resources and consensus that the materials needed improvement. We hypothesized that an OPAT education video would improve OPAT staff satisfaction with the educational offerings.Figure 1.OPAT Video Link Engagement (2024)Figure 2.Patient Electronic Chart Message Methods Adult patients ( > 18 years of age) enrolled in OPAT programs at 4 sites within Mayo Clinic throughout Minnesota and Wisconsin from 5/1/23 - 8/1/24 were included. A standardized OPAT patient education video was developed using voice over PowerPoint slides. Video content included lab monitoring requirements, signs and symptoms of adverse effects including alarm symptoms, and intravenous catheter care. The video was available as a link for delivery via patient electronic chart message, to be played on clinic and hospital room computers, and accessed by patients via QR code on rack cards. We implemented inclusion rules built within our electronic health record which automated the delivery of these patient chart messages. The primary outcome was staff satisfaction with OPAT education materials. Secondary metrics included number of video patient accesses in hospital and clinic rooms, number of message deliveries, and frequency of message opening. Staff satisfaction with OPAT education was compared pre- and post-intervention using the Pearson chi-square test. Results The patient education video was accessed 73 times in hospital and clinic rooms and was delivered by automated patient chart message 157 times during the study period. Patient chart messages were opened 91.5% of the time. The percentage of staff who felt OPAT education materials needed improvement decreased from 90% pre-intervention to 38.1% post-intervention (p=0.05). Conclusion A standardized OPAT patient education video allowed for efficient electronic delivery of educational information to patients and improved OPAT staff satisfaction. Disclosures All Authors: No reported disclosures
P-1774. Clinical presentation of Cutaneous Leishmaniasis (CL) in returning travelers
Abstract Background Leishmaniasis is a rare protozoan parasitic disease transmitted through the bite of infected Phlebotomus and Lutzomyia sandflies. Clinical presentation is variable due to numerous species and host immunity differences. We present our clinical experiences with CL to guide timely diagnosis and treatment in returning travelers. Methods We retrospectively analyzed a cohort of adult patients 18+ years old who were diagnosed with CL from 2005 and 2025. We describe the demographic, clinical, and diagnostic features of CL. Results Biopsy-confirmed CL was diagnosed in 20 returning travelers (Table 1) from various endemic regions, most commonly Costa Rica (Fig. 1). The median time from travel to symptom onset was 36.5 days (SD 102), with an additional 75.5 days (SD 87) prior to biopsy diagnosis. All patients were evaluated by dermatology and 70% were evaluated by infectious disease (n=14). On initial presentation, lesions were described as ulcerated (50%, n=10), nodular (30%, n=6), painful (20%, n=4), and necrotic (10%, n=2; Fig. 2). Most lesions were located on the upper extremity (55%, n=11), followed by the face (35%, n=7), lower extremity (30%, n=6), and trunk (15%, n=3). 15% of individuals (n=3) had constitutional symptoms. No patients had definitive mucosal involvement, however, 10% (n=2) endorsed lip edema. No patients had visceral involvement. Species level identification occurred in 14 cases (70%), of which the most common was L.V. panamensis (50%), L.L. mexicana (21%), L. V. guyanensis (14%), L. L. tropica (7%), and L. V. braziliensis (7%). Initial treatments included azoles, liposomal amphotericin B (AmBisome), and miltefosine (each 20%); cryotherapy and parenteral pentamidine (each 10%); with compounded topical paromomycin added in 15% of cases. 35% of individuals (n=7) failed initial treatment and required additional treatment courses due to persistent lesions (57%) or relapse following initial resolution (14%). 10% (n=2) required a third treatment course due to persistent/recurrent lesions. Conclusion While CL in travelers has a variety of clinical manifestations, travel history, knowledge of key clinical features, and lesion patterns can aid in early diagnosis and treatment. CL is associated with early treatment failure rate for uncertain reasons. Disclosures All Authors: No reported disclosures
Assessment of Clinical Significance of Molecular
Streptococcus agalactiae
Detection in Patients With Suspected Pneumonia
Abstract Background Streptococcus agalactiae (group B Streptococcus [GBS]) may cause pneumonia or may colonize the respiratory tract, making its clinical significance uncertain when detected in respiratory specimens. This study aimed to assess whether clinicians interpreted GBS detected by the BIOFIRE Pneumonia Panel (BF-PP) as a pathogen implicated in pneumonia. Methods This retrospective cohort study included adult patients hospitalized with suspected pneumonia at Mayo Clinic, Rochester, between September 2020 and February 2025. Cases were independently classified into pathogen and nonpathogen groups by 2 infectious diseases (ID) specialists, with a third reviewer resolving disagreements. Clinical characteristics and outcomes of both groups were recorded. A subgroup analysis of patients who had an ID consultation was performed. Results A total of 109 cases were included. GBS was considered a pneumonia pathogen in 47.7% of cases and a nonpathogen in 52.3%. ID consultation was performed in 33.0% of cases, with GBS considered a pathogen in 30.6% of those. Common comorbid conditions included pulmonary, gastrointestinal, neurologic, and cardiovascular disease and obesity. Rates of endotracheal intubation were similar in the pathogen and nonpathogen groups (51.9% vs 50.9%, respectively), with the in-hospital mortality rate being numerically but not significantly higher in the former versus the latter (21.2% vs 14.0%; P = .33); findings were similar in the ID-assessed subgroup. In 76.1% of GBS detections, other microorganisms—most commonly Staphylococcus aureus—were codetected. Only 10.2% of BF-PP GBS-positive specimens were culture positive for GBS. Conclusions While GBS is not an uncommon pneumonia pathogen, the clinical significance of its detection by BF-PP is uncertain in many cases.
The Use of Perioperative Cephalexin in Penicillin Allergic Patients in Dermatologic Surgery: An Advisory Statement
BACKGROUND Approximately 10% of patients report penicillin allergy. Based on historical guidelines, patients with a penicillin allergy should receive an alternative to cephalexin for prophylaxis in dermatologic surgery. OBJECTIVE To determine, based on evidence, if cephalexin should be used as a first-line prophylactic antibiotic in dermatologic surgery for patients with penicillin allergy. METHODS Systematic review of the literature was performed with defined search terms. RESULTS Less than 5% of those with penicillin allergy labels have a true penicillin allergy. For patients with true, persistent penicillin allergy, there is an overall low cross-reactivity with cephalosporins, especially with cephalosporins that do not share identical R1 side chain. The first-generation cephalosporins, including cephalexin, have a slightly higher risk of cross-reactivity in patients with reported allergy to amino-penicillins (amoxicillin, ampicillin) but not other penicillins. The risk of severe cross-reactivity of cephalosporins in patients with low-risk penicillin allergies is extremely low. Cephalexin has a superior side effect profile and efficacy compared to alternatives. CONCLUSION Cephalexin should be used as the first-line prophylactic antibiotic in dermatologic surgery for patients with documented penicillin allergy, including anaphylaxis. There may be a higher risk of cross-reactivity with cephalexin in patients with a confirmed amino-penicillin allergy.
Performance of BIOFIRE FILMARRAY pneumonia panel in suspected pneumonia: insights from a real-world study
ABSTRACT Pneumonia may be caused by a diverse group of microorganisms; however, a microbiologic diagnosis is not universally made. Molecular tests such as the BIOFIRE FILMARRAY Pneumonia Panel (BF-PP) offer the possibility of rapid identification of potential pneumonia pathogens. This retrospective analysis was conducted as a sub-study of a recently published randomized controlled trial. Specimens from patients with suspected pneumonia were tested by the BF-PP, with results compared to cultures. The overall BF-PP positivity rate was 44.8% (252/563), and was higher [64.6% (164/254)] in specimens from patients ultimately diagnosed with pneumonia. Discrepancies between the BF-PP and cultures were most common for Streptococcus pneumoniae , Haemophilus influenzae , Moraxella catarrhalis, and Streptococcus agalactiae . Positive percent agreement (PPA) and negative percent agreement (NPA) between the BF-PP and culture were 91.4% (CI 86.3%–94.9%) and 83.6% (CI 79.5%–87.2%), respectively. For most bacteria, a correlation between high genomic abundance (genomic copies/mL) reported from the BF-PP and culture growth abundance was found. In specimens from patients ultimately diagnosed with pneumonia, clinical consistency—assessed based on whether BF-PP results aligned with associated culture results—was 79.9% and was highest for bronchoalveolar lavage fluid specimens. The BF-PP has reliable analytical performance and offers the potential advantage over conventional cultures of providing higher detection rates and more rapid results. Interestingly, despite the use of this advanced molecular diagnostic tool, one-third of pneumonia cases remained without a microbiologic etiology. IMPORTANCE This study evaluates the BIOFIRE FILMARRAY Pneumonia Panel by comparing its performance to conventional cultures in a real-world patient population (including patients ultimately diagnosed as not having pneumonia) using different types of specimens. Findings show a higher detection rate of microorganisms with the panel compared to cultures, suggesting that this test could aid in tailoring treatments for pneumonia. However, challenges remain and require further study, including distinguishing true pathogens from colonizing microorganisms and determinig why one-third of patients diagnosed with pneumonia still lacked a microbiologic etiology.
Antimicrobial-induced neutropenia in patients receiving OPAT or COpAT: A large multisite retrospective cohort study
Abstract Purpose Data regarding the incidence, onset, and management of complex outpatient antimicrobial therapy–induced neutropenia (COIN) are limited, and pharmacist involvement in COIN management has not been reported. This report describes the incidence, onset, and management of COIN at a large academic medical center. Methods This multisite retrospective cohort study examined adult patients undergoing serum laboratory monitoring for antimicrobials over a 4-year period. Patients receiving chemotherapy or immunosuppressants were excluded. Data collected included the antimicrobial regimen, complete blood count, duration of antimicrobial therapy until outcome occurrence, infectious syndrome, type of intervention, outcome, and pharmacist involvement. Logistic regression was used to assess risk factors for COIN incidence. The primary outcome was the incidence of COIN by antimicrobial drug. Results From 4,261 treatment episodes, 161 cases of COIN were identified (3.8% COIN incidence). The most common antimicrobials associated with COIN were intravenous piperacillin/tazobactam, cefepime, and meropenem. The majority of COIN events were attributed to a combination of at least 2 antimicrobials. Piperacillin/tazobactam was significantly associated with higher odds of developing COIN (odds ratio [OR], 1.86; 95% confidence interval [CI], 1.04-3.34; P = 0.038), whereas ertapenem was associated with significantly lower odds of COIN (OR, 0.43; 95% CI, 0.24-0.77; P = 0.005). The median time to neutropenia diagnosis was 22 days (interquartile range, 14-29 days) from the time of inpatient antimicrobial start. Intervention for COIN occurred in 66.5% of cases, with neutrophil count recovering in 96.9% of these patients. Clinical pharmacists initiated 74.8% of interventions. Conclusion COIN can be effectively identified and managed by a multidisciplinary team reviewing routine laboratory monitoring, enabling most patients to safely complete antimicrobial treatment.
P-1713. Impact of an Evidence-Based Order Panel on Antimicrobial Prescribing in Ambulatory Patients with Complicated and Uncomplicated Cystitis
Abstract Background Optimizing antimicrobial prescribing for urinary tract infections (UTI) represents an area of opportunity for ambulatory antimicrobial stewardship programs. A pre-populated, ambulatory antibiotic order panel for UTI was implemented in the Mayo Clinic Enterprise on 5/16/2022. The order panel provides antimicrobial regimens which align with both institutional and national treatment guidelines based on patient comorbidities, complicating factors, and beta-lactam allergy status. We aimed to assess the impact of panel use on antibiotic prescribing for complicated and uncomplicated cystitis in the ambulatory setting. Methods This retrospective review included ambulatory encounters from the Mayo Clinic Enterprise in 2022 and 2023. Eligible encounters were randomly selected and included those with a primary ICD-10 code of cystitis performed by primary care or urgent care clinicians. Encounters were excluded if patients had symptoms indicative of pyelonephritis, underwent urinary instrumentation within 30 days, or had a urinary pathogen isolated within 90 days. The primary outcome was concordance with institutional guidelines. Secondary outcomes included repeat healthcare contact and therapy duration. Outcomes were analyzed with Pearson's chi-squared and Wilcoxon rank sum tests (α level = 0.05). Results 793 encounters (397 panel vs. 396 non-panel) were included. Prescribing was guideline concordant in 79.3% and 64.9% (p< 0.001) of panel and non-panel encounters, respectively. Inappropriate duration was the most common reason for non-concordance in the panel use cohort. There was no difference between groups for repeat healthcare contact incidence. Antimicrobials prescribed differed between panel and no-panel groups (Table 1), with higher use of sulfamethoxazole/trimethoprim and lower use of cefdinir in the panel cohort. Numerically shorter durations were seen in the panel group, with more 3- and 5-day regimens than the no-panel group. Conclusion Use of a pre-populated antimicrobial order panel for outpatient cystitis encounters resulted in greater adherence to institutional guideline recommendations, particularly in terms of antimicrobial selection, without adversely impacting repeat healthcare contact. Disclosures Paschalis Vergidis, MD, MSc, AbbVie: Advisor/Consultant|Ansun Biopharma: Grant/Research Support|Cidara Therapeutics: Grant/Research Support|F2G: Grant/Research Support|Scynexis: Advisor/Consultant|Scynexis: Grant/Research Support