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.

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.

Abstract Clinical significance of a single positive blood culture bottle (SPBCB) with Staphylococcus aureus is unclear. We aimed to assess the significance of an SPBCB by looking at the associated outcomes. We performed a retrospective, multicenter study of patients with an SPBCB with S aureus using data collected from both electronic health records and the clinical microbiology laboratory. Overall, 534 patients with S aureus bacteremia were identified and 118 (22.1%) had an SPBCB. Among cases with an SPBCB, 106 (89.8%) were classified as clinically significant whereas 12 (10.2%) were considered contaminated or of unclear significance. A majority (92.4%) of patients received antibiotic therapy, but patients with clinically significant bacteremia were treated with longer courses (25.9 vs 5.7 days, P < .001). Significant differences in both frequency of echocardiography (65.1% vs 84.6%, P < .001) and infective endocarditis diagnosis (3.8% vs 14.2%, P = .002) were seen in those with an SPBCB compared to those with multiple positive bottles. A longer hospital length of stay and higher 90-day, 6-month, and 1-year mortality rates were seen in patients with multiple positive blood culture bottles. An SPBCB with S aureus was common among our patients. While this syndrome has a more favorable prognosis as compared to those with multiple positive blood cultures, clinicians should remain concerned as it portends a risk of infective endocarditis and mortality.

A 78-year-old man with an implantable cardioverter-defibrillator (ICD) presented with chills and malaise. His history was significant for heart failure with reduced ejection fraction and complete heart block. He had undergone permanent pacemaker placement that was later upgraded to an ICD 5 years before his presentation. Physical examination revealed an open wound with surrounding erythema overlying the device site. Blood cultures obtained on admission were negative. Transesophageal echocardiogram did not show valve or lead vegetations. He underwent a prolonged extraction procedure. Postoperatively, he developed septic shock and cultures from the device, and repeat peripheral blood cultures grew Staphylococcus simulans and Staphylococcus epidermidis. He was treated with intravenous vancomycin but had refractory hypotension, leading to multiorgan failure. He later expired after being transitioned to comfort care. The patient may have acquired S. simulans by feeding cows on a nearby farm, and the prolonged extraction procedure may have precipitated the bacteraemia.

Lawsonella clevelandensis, an emerging pathogen, was first described in 2016, and has been implicated in abdominal, breast and spinal abscesses in a limited number of cases. Being a fastidious organism, it is primarily identified with molecular methods. With the incorporation of broad-range PCR testing in clinical diagnostics, L. clevelandensis has been increasingly reported in the literature. We describe a case of a 65-year-old man who presented with bilateral psoas abscesses secondary to aorto-bi-iliac vascular graft infection with L. clevelandensis identified using 16S rRNA/PCR sequencing. The patient underwent surgical resection and replacement of infected graft, followed by 6 weeks of intravenous antibiotic therapy and then chronic suppression with doxycycline and cefadroxil. He was infection-free at last follow-up.