Chesdachai, Supavit

Abstract Vascular graft infection (VGI) is one of the most serious complications following arterial reconstructive surgery. VGI has received increasing attention over the past decade, but many questions remain regarding its diagnosis and management. In this review, we describe our approach to VGI through multidisciplinary collaboration and discuss decision making for challenging presentations. This review will concentrate on VGI that impacts both aneurysms and pseudoaneurysms excluding the ascending thoracic aorta.

Abstract Vascular graft infection (VGI) is one of the most serious complications following arterial reconstructive surgery. VGI has received increasing attention over the past decade, but many questions remain regarding its diagnosis and management. In this review, we describe our approach to VGI through multidisciplinary collaboration and discuss decision-making for challenging presentations. This document will concentrate on VGI that impacts both aneurysms and pseudoaneurysms excluding the ascending thoracic aorta.

Abstract Background Nocardia tends to cause infection in immunocompromised patients or those with chronic pulmonary disease. Nocardia is known to recur, prompting the practice of secondary prophylaxis in patients perceived at high risk. However, few data exist regarding the epidemiology of recurrent nocardiosis or the effectiveness of secondary prophylaxis. Methods We performed a multicenter, retrospective cohort study of adults diagnosed with nocardiosis from November 2011 to April 2022, including patients who completed primary treatment and had at least 30 days of posttreatment follow-up. Propensity score matching was used to analyze the effect of secondary prophylaxis on Nocardia recurrence. Results Fifteen of 303 (5.0%) patients developed recurrent nocardiosis after primary treatment. Most recurrences were diagnosed either within 60 days (N = 6/15, 40.0%) or between 2 to 3 years (N = 4/15, 26.7%). Patients with primary disseminated infection tended to recur within 1 year, whereas later recurrences were often nondisseminated pulmonary infection. Seventy-eight (25.7%) patients were prescribed secondary prophylaxis, mostly trimethoprim-sulfamethoxazole (N = 67/78). After propensity-matching, secondary prophylaxis was not associated with reduced risk of recurrence (hazard ratio, 0.96; 95% confidence interval, .24–3.83), including in multiple subgroups. Eight (53.3%) patients with recurrent nocardiosis required hospitalization and no patients died from recurrent infection. Conclusions Recurrent nocardiosis tends to occur either within months because of the same Nocardia species or after several years with a new species. Although we did not find evidence for the effectiveness of secondary prophylaxis, the confidence intervals were wide. However, outcomes of recurrent nocardiosis are generally favorable and may not justify long-term antibiotic prophylaxis for this indication alone.

AbstractBackgroundGiven the challenges of conventional therapies in managing right‐sided infective endocarditis (RSIE), percutaneous mechanical aspiration (PMA) of vegetations has emerged as a novel treatment option. Data on trends, characteristics, and outcomes of PMA, however, have largely been limited to case reports and case series.Aims:The aim of the current investigation was to provide a descriptive analysis of PMA in the United States and to profile the frequency of PMA with a temporal analysis and the patient cohort.MethodsThe International Classification of Diseases, 10th Revision codes were used to identify patients with RSIE in the national (nationwide) inpatient sample (NIS) database between 2016 and 2020. The clinical characteristics and temporal trends of RSIE hospitalizations in patients who underwent PMA was profiled.ResultsAn estimated 117,955 RSIE‐related hospital admissions in the United States over the 5‐year study period were estimated and 1675 of them included PMA. Remarkably, the rate of PMA for RSIE increased 4.7‐fold from 2016 (0.56%) to 2020 (2.62%). Patients identified with RSIE who had undergone PMA were young (medial age 36.5 years) and had few comorbid conditions (median Charlson Comorbidity Index, 0.6). Of note, 36.1% of patients had a history of hepatitis C infection, while only 9.9% of patients had a cardiovascular implantable electronic device. Staphylococcus aureus was the predominant (61.8%) pathogen. Concomitant transvenous lead extraction and cardiac valve surgery during the PMA hospitalization were performed in 18.2% and 8.4% of admissions, respectively. The median hospital stay was 19.0 days, with 6.0% in‐hospital mortality.ConclusionsThe marked increase in the number of PMA procedures in the United States suggests that this novel treatment option has been embraced as a useful tool in select cases of RSIE. More work is needed to better define indications for the procedure and its efficacy and safety.

AbstractIn this clinicopathological conference, invited experts discussed a previously published case of a patient with nonischemic cardiomyopathy who underwent heart transplantation from a genetically modified pig source animal. His complex course included detection of porcine cytomegalovirus by plasma microbial cell‐free DNA and eventual xenograft failure. The objectives of the session included discussion of selection of immunosuppressive regimens and prophylactic antimicrobials for human xenograft recipients, description of infectious disease risk assessment and mitigation in potential xenograft donors and understanding of screening and therapeutic strategies for potential xenograft‐related infections. image

Abstract Background The treatment of invasive fungal infections (IFI) is often complicated by drug-drug interactions, toxicities, and host comorbidities. Isavuconazole (ISA) has a favorable side effect profile and has FDA approval for invasive aspergillosis and mucormycosis, but there are fewer data on its efficacy for other microbes and non-pulmonary infections. We report our experience of ISA in IFI treatment, with a particular focus on non-pulmonary sites and other microbial etiologies. Methods We identified patients who received ISA as part of IFI treatment from 1/1/2015–4/1/2020 at Mayo Clinic. We categorized them by organ involvement and by pathogens, and identified patterns of ISA use and clinical outcomes. Results A total of 131 patients were identified. Similar to the existing literature, the majority were pulmonary infections (60%), with 12% invasive sinus infection, 12% central nervous system (CNS) infection, and 7% fungemia. Aspergillus was the most common pathogen (39%), yeast comprised 19%, dimorphic fungi 15%, Mucormycosis 12%, phaeohyphomycosis 5%, and other molds 3%. ISA was used as secondary/salvage therapy in 89% of cases. The response rate varied by organ involvement and pathogen. ISA had complete/partial resolution or achieved stability in 57% of fungemia cases, 63% of invasive sinus infections, 64% of pulmonary infections, and 73% of CNS infections. Aspergillus species had a 67% response rate, with 72% response in yeast infections, 65% rate in dimorphic fungi, 53% for mucormycosis, and 86% in dematiaceous molds. Conclusion Although limited by a small sample size, the subgroup review based on organ site and microbial etiology did seem to show roughly similar results to approved uses. The CNS infections treated with ISA were particularly of interest, given the limited options available with reliable CNS penetration. The current available literature has little to say on the efficacy of ISA in these off-label uses, with the majority being similar case series. This report highlights the importance of prospective trials comparing ISA to other antifungals in a greater variety of indications to better identify when this better-tolerated agent can be safely used. Disclosures Courtney E. Harris, MD, Dynamed: Advisor/Consultant

Abstract Background Two independent placebo-controlled clinical trials conducted prior to SARS-CoV-2 Omicron demonstrated that sotrovimab and remdesivir reduced hospitalization among high-risk outpatients with mild to moderate COVID-19. However, their effectiveness have not been directly compared. Methods This retrospective study examined all high-risk outpatients with mild to moderate COVID-19 who received either remdesivir or sotrovimab at Mayo Clinic during the Omicron BA.1 surge from January to March 2022. COVID-19-related hospitalization or death within 28 days were compared between the two treatment groups. Results Among 3,257 patients, 2,158 received sotrovimab and 1,099 received remdesivir. Patients treated with sotrovimab were younger (median age, 60 vs. 69 years) and had lower comorbidity (Monoclonal Antibody Screening Score, 5 vs. 6; Charlson Comorbidity Index, 3 vs. 4), but were more likely to be immunocompromised (47.3% vs. 30.2%) than remdesivir-treated patients. The majority (89%) had received at least one dose of COVID-19 vaccine (median, 3 doses [IQR 2-3] for both groups). COVID-19-related hospitalization (1.5% and 1.0% in remdesivir and sotrovimab groups, respectively, p=.15) and mortality within 28 days (0.4% in both groups, p=.82) were similarly low. A propensity score weighted analysis demonstrated no significant difference in the rates of COVID-related hospitalization and death within 28 days between the two groups. Conclusion This study demonstrated favorable outcomes that were not significantly different between patients treated with remdesivir or sotrovimab. As sotrovimab is no longer authorized, these results support the continued use of remdesivir for treating high-risk patients with COVID-19 during the current Omicron-predominant epoch. Disclosures Christina G. Rivera (O'Connor), Pharm.D, Gilead Sciences: Advisor/Consultant|Gilead Sciences: Board Member|Gilead Sciences: Grant/Research Support|Gilead Sciences: Honoraria Maria Gonzalez Suarez, M.D., Ph.D., Gilead: Grant/Research Support Ravindra Ganesh, M.B.B.S., M.D., Alpaca Health: Advisor/Consultant Raymund R. Razonable, MD, Allovir: Endpoint Adjudication Committee|American Society of Transplantation: Board Member|Gilead: Grant/Research Support|Novartis: DSMB|Regeneron: Grant/Research Support|Roche: Grant/Research Support

Abstract Background Remdesivir is FDA-approved for the treatment of hospitalized patients with severe COVID-19. Many patients improve clinically to allow for hospital dismissal before completing the 5-day course. In prior work, those who continued remdesivir in an outpatient setting had better outcomes. Here, we assessed patients’ perspectives and the economic impact of this outpatient practice. Methods During a one-year period, 3,029 patients received remdesivir for COVID-19 in the hospital; of them, 542 were dismissed to continue remdesivir in the outpatient setting and were surveyed. The cost of care was compared between those who remained in the hospital vs. those who were dismissed. Results 470 of 542 patients were surveyed, and 93 (19.8%) responded. Responders were older than non-responders (median, 63 vs. 58 years). The majority (70.5%) had symptoms resolved by the time of the survey. Ten patients (11.4%) had persistent symptoms attributed to long COVID-19, including fatigue (30.1%), brain fog (23.7%), and insomnia (18.3%). 73.8% were excited to learn about the outpatient remdesivir program. The majority (81.0%) felt that receiving therapy at home was the right decision; 79.5% had support and felt the benefits of completing treatment at home. The majority were satisfied with communication before (75.6%) and during (80.5%) the outpatient appointment, information on benefits (80.3%) and risks (58.5%), time spent at the infusion center (88.6%), quality of care (82.3%) and overall experience (76.0%). The benefits of treatment were high-value (82.6%), while the infusions' cost, inconvenience, and discomfort were unimportant for most responders. After adjusting for gender, comorbidity score, and WHO scale, the predicted costs for the groups were $16,544 (inpatient) and $9,097 (outpatient) per patient (difference of $7,447; p< .01). During this study, we estimated a total of 1,077 hospital room-days were made available to other patients. Conclusion An outpatient remdesivir program that allowed for early dismissal was perceived favorably by patients hospitalized for COVID-19. The program resulted in significant cost and resource savings, the latter in terms of the availability of hospital rooms for other patients needing critical services. Disclosures Christina G. Rivera (O'Connor), Pharm.D, Gilead Sciences: Advisor/Consultant|Gilead Sciences: Board Member|Gilead Sciences: Grant/Research Support|Gilead Sciences: Honoraria Bijan J. Borah, Ph.D., Boehringer Ingelheim: Advisor/Consultant|Exact Sciences: Advisor/Consultant Ravindra Ganesh, M.B.B.S., M.D., Alpaca Health: Advisor/Consultant Raymund R. Razonable, MD, Allovir: Endpoint Adjudication Committee|American Society of Transplantation: Board Member|Gilead: Grant/Research Support|Novartis: DSMB|Regeneron: Grant/Research Support|Roche: Grant/Research Support

Abstract Background Staphylococcus aureus bacteriuria (SABU) represents 0.2–4% of all positive urine cultures. While asymptomatic colonization or infection of the urinary tract is possible, hematogenous seeding from S. aureus bacteremia (SAB) represents a potentially life-threatening condition. The rate of concomitant SAB is estimated to be 6.9–17.2% among those with SABU, and these patients are at higher risk of in-hospital mortality, infective endocarditis, embolic events, and vertebral osteomyelitis. Detection of SABU represents an opportunity for early detection and intervention in SAB. Methods We conducted a retrospective analysis of clinical and microbiological characteristics of adult patients with SABU as our pre-intervention baseline. We then implemented a comment with the urine culture result in the electronic medical record (EMR) advising providers about the possibility of concomitant bacteremia. We conducted an interim analysis of early post-intervention data. Figure 1: Study Workflow Figure 1: Study workflow depicting case recruitment and blood culture results. Figure 2: Intervention Flag Figure 2: Example of intervention comment displayed with the urine culture result in the EMR. Results 250 adult patients developed SABU from January 1, 2021, to January 31, 2023. Of these, 87 (34.8%) had urinary tract symptoms, and 91 (36.4%) had a chronic indwelling urinary catheter. 74 (29.6%) patients had blood cultures collected within 7 days of positive urine culture. The presence of urinary symptoms or indwelling catheter was not associated with blood culture collection. Only 22 patients (8.8%) had SAB with SABU. One patient was diagnosed with SAB 20 days after detection of SABU with infective endocarditis and disseminated infection, representing a delay in diagnosis. Following implementation of the intervention, an additional 86 patients with SABU had the result comment displayed in the EMR. Blood cultures were collected in 19 (22.1%) patients, and 2 (2.3%) were positive for S. aureus. There were no significant differences in rates of blood culture collection or SAB after implementation of the EMR result comment. Conclusion Our results show a similar rate of SABU associated SAB to that previously reported in the literature. Delayed diagnosis of SAB in SABU is uncommon but does occur rarely with significant morbidity. The addition of a result comment is a simple and cost-effective intervention; however, evaluation of its efficacy is presently limited by a short follow-up duration. Disclosures All Authors: No reported disclosures

Abstract Background Human granulocytic anaplasmosis (HGA) is an emerging tick-borne illness endemic to the northeastern and midwestern United States. Risk factors for the severity of infection, predictors for hospitalization, temporal trends, co-infections, and outcomes are poorly studied. Methods We conducted a retrospective review of HGA at Mayo Clinic, Rochester, between 2011-2021. Cases were identified by positive Anaplasma PCR at our reference laboratory. Variables included patients’ characteristics, symptoms, risk factors for tick-borne illness, laboratory parameters, co-infections, treatment, and clinical outcomes. Results We identified 471 cases with a positive Anaplasma PCR, and 146 cases were included in this interim analysis. Table 1 shows a summary of the baseline characteristics. An increasing annual trend in diagnosis of HGA was noted from 2014 to 2016 with lower rates observed during COVID-19 pandemic (2020 to 2022) (Figure 1). Of the 146 patients, 19 (13%) were immunocompromised secondary to hematologic malignancies, solid organ malignancies, and pharmacological immunosuppression. Frequently reported symptoms included fever (79.5%), malaise (68.5%), chills (51.4%), and myalgia (50%). Tick exposure was documented in 79.2 % of cases. Forty-seven (33%) patients were hospitalized; older patients were more likely to be hospitalized (Table 2). The most common complications among the hospitalized patients included respiratory failure (50%), encephalopathy (44.4%) and renal failure (37.5%). One patient required ICU admission. Twenty-five patients (17.5%) and one patient (0.7%) were co-infected with Lyme and Ehrlichiosis, respectively. Higher rates of leukopenia and thrombocytopenia were associated with mono-infection with Anaplasma (p < 0.001). Follow up data was available for 136 patients; all of them had favorable response to doxycycline.Table 1:Summary of baseline characteristics, labs and treatment.Table 2:Predictors of HospitalizationFigure 1:Annual Trends in Anaplasmosis from 2011-2021. Conclusion Our study demonstrated comprehensive clinical characteristics of patients with HGA. Interestingly, tick exposure history was common, yet most patients did not have other tick-borne co-infections. Furthermore, only a minority of patients developed severe diseases and required hospitalization. The recent decline in cases during the early part of the COVID-19 pandemic is worth further investigation. Disclosures All Authors: No reported disclosures