Sohail, M. Rizwan

Background: Aortic endograft infection (AEGI) is a rare complication of abdominal endovascular aortic repair (EVAR) and thoracic endovascular aortic repair (TEVAR). Surgical explantation with reconstruction is recommended, but data on medical management remain limited. We present our institutional experience with AEGI. Objective: To describe the clinical presentation, microbiology, management strategies, and outcomes of patients with AEGI, with the aim of addressing current gaps in the literature and informing future research to improve patient outcomes. Design: Retrospective descriptive study. Methods: Adult patients admitted with AEGI at our institution between January 2017 and August 2024 were identified using ICD-10 codes and confirmed using the Management of Aortic Graft Infection Collaboration (MAGIC) diagnostic criteria. Clinical, microbiological, radiographic, treatment, and outcome data were collected and analyzed. Results: We screened 517 patients, and 46 met AEGI criteria (EVAR 54%, TEVAR 46%). Most (63%) presented with late-onset infections (⩾3 months). Fever (54%) and sepsis (48%) were common presenting symptoms. Computed tomography (CT) (85%) was the primary imaging modality. Blood cultures were positive in 54% of the cases, with Staphylococcus aureus being the most common monomicrobial pathogen (24%), and 24% of cases were polymicrobial. The majority (67%) received combined medical and surgical therapy. Chronic antibiotic suppressive therapy was used in 34 (74%), most often tetracyclines (33%). Overall, treatment success rates were similar between surgical and medical groups (58% vs 60%, p = 0.250) with comparable mortality. However, relapses were more frequent in the medical-only group (33% vs 16%, p = 0.185). Conclusion: Most patients presented with late-onset AEGI. Fever was absent in nearly half of cases, and blood cultures were positive in only 54%. Overall, surgical and medical therapy had similar success, though relapses were more frequent in those treated medically alone.

Background: Preventing infections associated with cardiac implantable electronic devices (CIED) and neurostimulators is essential to optimizing patient outcomes. This study aimed to evaluate the antimicrobial performance of a biologic CIED envelope incorporating a bioabsorbable disc infused with rifampin and minocycline. Methods: The antimicrobial activity was evaluated in a rabbit model and in vitro elution tests. Based on in vivo–in vitro correlation studies, a modified AATCC-100 method was used to quantitatively assess antibacterial activity across seven bacterial strains relevant to CIED infections. Results: Pharmacokinetic analysis showed a biphasic elution profile, with rapid initial release followed by more gradual elution over 14 days. The AATCC results showed no bacterial recovery for any tested species, with complete eradication in all replicates. Conclusions: These results support the use of antibiotic-eluting bioenvelopes as an effective strategy for preventing bacterial infections associated with CIED. The modified AATCC-100 test and in vivo–in vitro correlation studies provide new tools for the evaluation of the antibiotic activity of implantable biomaterials.

Abstract Based on expert consensus, the American Society of Transplantation recommends 7–14 days of preventive antibiotic therapy for solid organ transplant recipients from donors with positive blood cultures. We evaluated management and outcomes of kidney transplant recipients from these donors.

Abstract Cardiac implantable electronic device infection in the context of corynebacterial bloodstream infection (BSI) remains poorly understood. From 2012 to 2023 at Mayo Clinic, 4 of 12 patients with corynebacterial BSI had cardiac implantable electronic device infection: 1 patient was diagnosed during a relapsing BSI episode. Undefined source, persistent BSI, and the presence of a prosthetic cardiac valve were common characteristics.

Introduction: Implantable cardioverter-defibrillators (ICDs) reduce morbidity and mortality in appropriately selected patients, but device-related infections are associated with significant mortality that can mitigate this benefit. Women are at higher risk for adverse events during ICD procedure admissions, but there are limited data on the mortality associated ICD infection in women. Objective: To compare the clinical characteristics and mortality rate of men and women who have an infection associated with ICD procedure. Methods: Retrospective cohort study of 64,903 Medicare fee-for-service patients admitted for ICD generator implantation, replacement, or revision from January 1, 2007 to December 31, 2007. Primary outcome measures were unadjusted and risk-adjusted longer-term mortality associated with ICD infection. Results: There were a total of 1,855 (2.89%) admissions with an ICD infection. Longer-term mortality (death during admission quarter and subsequent 4 quarters) was significantly higher with ICD infection than without (28.4% vs. 16.7%, P<0.001). While longer-term mortality without ICD infection was significantly lower for women (hazard ratio=0.89 [95%CI 0.85-0.93]), longer-term mortality with ICD infection was significantly higher for women, compared to men (hazard ratio=1.20 [95%CI 1.03-1.41]. Multivariate regression analysis adjusting for age, gender, race/ethnicity and 28 comorbidities demonstrated a significant interaction between gender and ICD infection associated short and, and longer-term mortality. The risk-adjusted longer-term mortality with ICD infection was significantly higher for women compared to men (hazard ratio = 1.25 [95% CI 1.02-1.53]). Conclusions: Women have significantly higher rate of death, compared to men, following infection associated with ICD procedures. Further studies to determine the underlying causes of this disparity are warranted.

Abstract Background In contrast to bloodstream infection due to a variety of bacteria in patients with cardiovascular implantable electronic devices (CIED), there are limited data regarding candidemia and risk of CIED infection. Methods All patients with candidemia and a CIED at Mayo Clinic Rochester between 2012 and 2019 were reviewed. Cardiovascular implantable electronic device infection was defined by (1) clinical signs of pocket site infection or (2) echocardiographic evidence of lead vegetations. Results A total of 23 patients with candidemia had underlying CIED; 9 (39.1%) cases were community onset. None of the patients had pocket site infection. The duration between CIED placement and candidemia was prolonged (median 3.5 years; interquartile range, 2.0–6.5). Only 7 (30.4%) patients underwent transesophageal echocardiography and 2 of 7 (28.6%) had lead masses. Only the 2 patients with lead masses underwent CIED extraction, but device cultures were negative for Candida species. Two (33.3%) of 6 other patients who were managed as candidemia without device infection subsequently developed relapsing candidemia. Cardiovascular implantable electronic device removal was done in both patients and device cultures grew Candida species. Although 17.4% of patients were ultimately confirmed to have CIED infection, CIED infection status was undefined in 52.2%. Overall, 17 (73.9%) patients died within 90 days of diagnosis of candidemia. Conclusions Although current international guidelines recommend CIED removal in patients with candidemia, the optimal management strategy remains undefined. This is problematic because candidemia alone is associated with increased morbidity and mortality as seen in this cohort. Moreover, inappropriate device removal or retention can both result in increased patient morbidity and mortality.

Abstract Background Cardiovascular implantable electronic devices (CIED) infection carries significant morbidity, mortality, and financial burden. Bacteremia in patients with CIED increases risk of CIED infection. While several investigations have examined Staphylococcus aureus bacteremia and risk of CIED infection, data regarding non-S. aureus gram-positive coccal (non-SA GPC) bacteremia in patients with CIED has been both limited and dated. The current study examined the clinical characteristics of patients with CIED who developed non-SA GPC bacteremia and their proclivity of CIED infection. Methods We reviewed all patients with CIED who developed non-SA GPC bacteremia at Mayo Clinic between 2012–2019. Cases with a left ventricular assist device, non-hospitalization, and contaminated blood culture were excluded. The 2019 European Heart Rhythm Association International Consensus Document was used to define CIED infection. Results A total of 160 patients with CIED developed non-SA GPC bacteremia during the period. Ninety (56.2%) patients had CIED infection, with 60 (37.5%) classified as definite and 30 (18.8%) possible. This included 41/64 (64.1%) patients with coagulase-negative Staphylococcus (CoNS), 30/41 (73.2%) patients with Enterococcus, 13/19 (68.4%) patients with viridans group streptococci (VGS), and 6/36 (16.6%) patients with other non-SA GPC. The odds of CIED infection (with 95% CI) for CoNS, Enterococcus, and VGS bacteremia were 8.9 (3.2–24.6), 13.6 (4.5–41.6), and 10.8 (2.9–40.0) -fold higher, respectively, as compared to other non-SA GPC. Among those with infected CIED, 51 (56.7%) patients underwent complete device extraction after a median of 6 (IQR 3.5–10) days. In an unadjusted analysis of patients with CIED infection, the reduction in one-year mortality following device removal was not statistically significant (HR 0.59, 95% CI 0.26–1.33, p=0.198). Conclusion The overall prevalence of CIED infection following non-SA GPC bacteremia was higher than previously reported, particularly that due to CoNS, Enterococcus, and VGS. Further study with a larger cohort is needed to demonstrate the survival benefit from CIED extraction in patients with infected CIED due to non-SA GPC. Disclosures Larry M. Baddour, M.D., Boston Scientific: Advisor/Consultant|Botanix Pharmaceuticals: Advisor/Consultant|Roivant Sciences: Advisor/Consultant|UpToDate, Inc.: Royalty payments - authorship duties Rizwan Sohail, M.D., Aziyo Biologics: Advisor/Consultant|Boston Scientific: Advisor/Consultant|Medtronic: Advisor/Consultant|Philips: Advisor/Consultant|Philips: Honoraria Malini Madhavan, M.B.B.S., Biosense Webster: Advisor/Consultant|Biotronik Inc: Advisor/Consultant|Boston Scientific: Grant/Research Support|Convatec: Advisor/Consultant.

Abstract Background Fungal infections following pancreas transplantation carry significant morbidity and mortality with an estimated incidence of 3 to 28%. The American Society of Transplantation (AST) suggests considering fluconazole prophylaxis in pancreas transplant recipients (PTR) at high-risk of invasive candidiasis (IC). However, optimal dosage and duration of prophylaxis is unclear. Weekly fluconazole for prevention of IC has been previously reported in liver and bone marrow transplant recipients. We analyzed outcomes of once weekly fluconazole prophylaxis in PTR. Methods We retrospectively reviewed all pancreas transplants performed at our institution from January 2017 through September 2021. PTR at high-risk for IC were defined per AST criteria as those with enteric drainage, vascular thrombosis, and post-perfusion pancreatitis. Patients received once weekly oral fluconazole 200 mg for 12 weeks post-transplant for IC prophylaxis. We analyzed incidence of breakthrough IC within the first 6 months post-transplant. Results We identified a total of 22 PTR, all of whom received simultaneous kidney transplantation from deceased donors. Of these, 12/22 (55%) were male and 11/22 (50%) were African American. Median age at the time of transplantation was 39 years (IQR 34-46). The most common indication for transplantation was type 1 diabetes mellitus (17/22, 21%) with associated nephropathy. No donor organ cultures were positive for fungi and all pancreas transplants were performed using enteric drainage. Notably, one patient developed pancreas allograft thrombosis while another developed pancreatitis. No patients required early discontinuation of fluconazole due to intolerance or side effects and none developed breakthrough IC within 6 months post-transplant (Table 1). Table 1. Conclusion Weekly fluconazole prophylaxis has not been previously studied in PTR. In our cohort, this approach was well tolerated, with no cases of IC at 6 months post-transplantation in patients at high-risk. Randomized controlled clinical trials are needed to define the optimal strategy in this population. Disclosures M. Rizwan Sohail, MD, Aziyo Biologics: Honoraria|Boston Scientific Corporation: Honoraria|Medtronic: Grant/Research Support|TRYX: Grant/Research Support.

Abstract Background Gram-negative bacteremia (GNB) as a manifestation of cardiovascular implantable electronic device (CIED) infection is uncommon. Moreover, echocardiography may be nonspecific in its ability to differentiate whether CIED lead masses are infected. We aimed to determine the rate of CIED infection in the setting of GNB. Methods All patients with CIED who were hospitalized with GNB during 2012–2019 at Mayo Clinic were investigated. The definition of CIED infection was based on criteria recommended by the 2019 European Heart Rhythm Association document. Results A total of 126 patients with CIED developed GNB. None of them had signs of pocket infection. Twenty (15.9%) patients underwent transesophageal echocardiography. Overall, 4 (3%) patients had definite CIED infection. None of them underwent CIED extraction; 3 died within 12 weeks and 1 received long-term antibiotic suppression. Ten (8%) patients had possible CIED infection; despite no CIED extraction, no patient had relapsing GNB. We observed a higher rate of CIED infection in patients with Serratia marcescens bacteremia as compared to that in patients with other GNB. Conclusions The rate of CIED infection following GNB was relatively low. However, accurate classification of CIED infection among patients presenting with GNB remains challenging, in part, due to a case definition of CIED infection that is characterized by a low pretest probability in the setting of GNB. Prospective, multicenter studies are needed to determine accurate identification of CIED infection among GNB, so that only patients with true infection undergo device removal.

Abstract Background Population-based studies of Staphylococcus aureus bacteremia (SAB) in the United States are limited. We provide a contemporary evaluation of SAB incidence in Olmsted County, Minnesota, from 2006 to 2020. Methods This was a retrospective population-based study of all adult patients with SAB residing in Olmsted County from 1 January 2006 through 31 December 2020. Initial episodes of SAB were identified using the microbiology laboratory databases at both Olmsted Medical Center and Mayo Clinic Rochester. Results Overall, 541 incident SAB cases were identified with a median age of 66.8 (interquartile range, 54.4–78.5) years, and 60.4% were male. Among these cases, 298 (56.2%) were due to methicillin-susceptible S aureus (MSSA) and 232 (43.8%) cases of methicillin-resistant S aureus (MRSA). The overall age- and sex-adjusted SAB incidence rate (IR) was 33.9 (95% confidence interval [CI], 31.0–36.8) cases/100 000 person-years (PY). Males had a higher age-adjusted IR of 46.0 (95% CI, 41.0–51.0) cases/100 000 PY compared to females (IR, 24.4 [95% CI, 21.1–27.7] cases/100 000 PY). Age- and sex-adjusted SAB IRs due to MSSA and MRSA were 18.7 and 14.6 cases/100 000 PY, respectively, and the percentage of incident SAB cases due to MRSA fluctuated across the study period. There was no apparent temporal trend in SAB incidence over the study period (P = .093). Conclusions Our investigation represents the only contemporary population-based study in the United States. Despite the impression that SAB incidence may have increased based on Centers for Disease Control and Prevention surveillance data, our finding of no change in SAB incidence was somewhat unanticipated.