Tabaja, Hussam

Abstract Patent foramen ovale (PFO) has a prevalence of approximately 25%. Its association with pyogenic brain abscess (PBA) is unclear. We reviewed adults with PBA and known PFO status from 1 January 2009 through 31 December 2021 at Mayo Clinic. High PFO prevalence (40.5%) was seen. PBA patients with PFO had distinct abscess characteristics but unchanged 1-year, all-cause mortality.

Abstract Cardiac implantable electronic device infections (CIEDIs) present substantial challenges for infectious diseases specialists, encompassing diagnosis, management, and complex decision making involving patients, families, and multidisciplinary teams. This review, guided by a common clinical case presentation encountered in daily practice, navigates through the diagnostic process, management strategies in unique scenarios, long-term follow-up, and critical discussions required for CIEDIs.

Abstract Background Vascular graft infection (VGI) is a rare but serious condition. Pathogen identification can be difficult given the deep-seated nature. Microbial cell-free DNA next-generation sequencing (mcfDNA NGS) is an emerging tool in non-invasive microbiologic workup. One commercially available mcfDNA is the Karius Test (KT). There is a paucity of data regarding utility and impact of mcfDNA NGS testing in the evaluation of VGI. Methods We retrospectively evaluated adult patients who underwent KT for evaluation of VGI at our institution. Only patients who met the Management of Aortic Graft Infection Collaboration (MAGIC) classification for suspected or confirmed VGI were included. We investigated the concordance between KT and conventional microbiologic workup. Conventional workup (CW) included pathogen identification through blood cultures, peri-graft/graft cultures, or histopathology. Concordance was defined by identical pathogen identification on KT and CW. We examined the influence of the KT result on clinical management.Figure 1.KT Results for Confirmed and Suspected VGI. Results We identified 25 patients who met criteria for either suspected or confirmed VGI per the MAGIC criteria. Microbiology was undefined in 8 patients who had negative KT and negative CW. A total of 17 patients had positive workup with 6 having positive KT and negative CW, 3 having negative KT and positive CW, and 8 having both positive KT and positive CW (Table 1). KT was less likely to be positive for patients who met criteria for suspected infection (4/10; 40%) as opposed to confirmed infection (10/15; 66.67%), albeit non-significant (OR 0.33, p=0.188) (Figure 1). The KT led to antimicrobial de-escalation in 27.3% of patients with positive CW and 35.7% of patients with negative CW (Figure 2). Full concordance of KT and CW was noted in 3 patients (Table 2).Figure 2.Influence of KT on VGI cases with positive and negative conventional work-up. Treatment escalation was defined as the broadening of antimicrobial coverage due to KT results. Treatment de-escalation was defined as narrowing/discontinuation of antimicrobial coverage due to KT results. Conclusion We found that the positivity rate for KT was 56%. KT impacted management in 40% of cases. Patients with confirmed VGI had a higher likelihood of having a positive KT. KT was the only positive microbiological definitive test in one case. Further studies are needed to explore the utility and impact of KT in the workup of VGI. Disclosures All Authors: No reported disclosures

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.

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 The objective of our study is to describe the clinical presentation, management, and outcome of a large cohort with nontuberculous mycobacteria (NTM) hand infection. Methods We reviewed the medical records of all adults (≥18 years) managed at the Mayo Clinic (Rochester, MN) for NTM hand infection between 1998 and 2018. Results Our cohort included 81 patients. The median age was 61.3 (interquartile range 51.7, 69.6) years; 39.5% were immunocompromised, and 67.9% reported a triggering exposure preceding infection. Infection was deep in 64.2% and disseminated in 3.7%. Up to 16.0% received intralesional steroids because of misdiagnosis with an inflammatory process. Immunocompromised patients had deeper infection, and fewer reports of a triggering exposure. Mycobacterium marinum, Mycobacterium avium complex, and Mycobacterium chelonae/abscessus complex were the most common species. The median antibiotic duration was 6.1 (interquartile range 4.6, 9.9) months. Deep infection and infection with species other than M marinum were associated with using a greater number of antibiotics for combination therapy and an extended duration of treatment. Immunosuppression was also associated with longer courses of antibiotic therapy. Surgery was performed in 86.5% and 32.4% required multiple procedures. Ten patients, mostly with superficial infections, were treated with antibiotics alone. The 5-year cumulative rate of treatment failure was 30.3% (95% confidence interval, 20.9–44.0). Immunosuppression and intralesional steroid use were risk factors for failure. Conclusions Treatment of NTM hand infection usually requires surgery and antibiotics, but antibiotics alone may occasionally be attempted in select cases. Immunosuppression and intralesional steroids are risk factors for treatment failure.

Abstract Background Catheter-related bloodstream infection (CRBSI) is an important complication of long-term central venous catheters (CVCs) and is associated with high morbidity and cost. While line removal is optimal, it is not always feasible and is not without complications. Antibiotic lock therapy (ALT) may be an alternative strategy for line salvage, but the efficacy of this approach particularly among immunocompromised hosts is unknown. Methods We retrospectively reviewed adult patients with CRBSI managed with ALT between 2018 and 2022 at our tertiary medical center. We reviewed patient comorbidities, type and indications for CVC use, microbiology of CRBSI, ALT, and use of systemic antibiotics. Outcomes included 30-day mortality, 90-day microbiologic relapse (with same bacteria as index case), 90-day recurrent BSI (with different bacteria from index case), and adverse events. Results 86 patients were reviewed, a majority of whom were immunocompromised (91%) due to hematopoietic stem cell transplantation (85%) and thrombocytopenic (platelet count 36; IQR 17-112). 78% had tunneled CVC for indications including peri-transplant therapy (72%), chemotherapy (15%), and TPN (6%) (Table 1). The median time to CRBSI following CVC insertion was 45 days (IQR 19-86). Infections were frequently monomicrobial (80%) due to Gram-positive organisms (n=75) including coagulase-negative staphylococci and Enterococcus spp. The minority of Gram-negative (n=17) infections were due to E coli and Enterobacter spp. 94% of patients received systemic antibiotics and all patients received ALT for a median of 11 days [IQR 6-15] and 11.5 days [IQR 6-14], respectively (Table 2). The 30-day attributable mortality rate was low at 1%. Rates of 90-day microbiologic relapse (20%) and recurrent BSI (16%) were high, occurring at a median of 42 days (IQR 12-55) and 35 days (IQR 25-50) following completion of ALT, respectively (Table 3). Conclusion Despite high rates of microbiologic relapse and recurrent BSI, ALT may be an effective line salvage strategy extending the use of CVC by up to 30 days with minimal impact on mortality even among immunocompromised patients. Disclosures John C. O'Horo, Sr., MD, MPH, Janssen Pharmaceuticals.: Grant/Research Support|nference: 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 Patent foramen ovale (PFO) can be identified in about 20-25% of the adult population and may result in variable degrees of left-to-right and right-to-left intracardiac shunting. The association between PFO and pyogenic brain abscess remains poorly understood. The current study aimed to compare the clinical characteristics and outcomes of pyogenic brain abscess in patients with and without PFO. Methods All adults with pyogenic brain abscess seen at Mayo Clinic from 1/1/2009-12/31/2021 who underwent either transesophageal echocardiography (TEE) or transthoracic echocardiography (TTE) with agitated saline shunt (bubble) study were included. Results A total of 222 patients developed pyogenic brain abscess during the study period; 148 (66.7%) patients were excluded due to unknown PFO status. Among 74 remaining patients, PFO was detected in 30 (40.5%) patients; 25 by TEE and 5 by TTE with bubble study (Figure 1). The prevalence of cryptogenic brain abscess (unable to identify the source of abscess) was significantly higher in patients with PFO as compared to those without PFO (53.3% versus 18.2%, p=0.002). Patients with PFO had a larger abscess size (25 mm [IQR 15.8-37.5] versus 15.5 mm [IQR 10.0-28.0], p=0.038). However, multiple abscesses were more common in the group without PFO (43.2% versus 20.0%, p=0.038). Additionally, patients with PFO had less documented bloodstream infection. There were no differences between other clinical characteristics and one-year, all-cause mortality between two groups. Conclusion These findings provide critical insights into the likely association between PFO and cryptogenic brain abscess; additional investigation is warranted. Disclosures Larry M. Baddour, MD, Boston Scientific: Advisor/Consultant|Roivant Sciences: Advisor/Consultant