Sohail, M. Rizwan

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.

Introduction: Cardiovascular implantable electronic devices (CIED) infections are frequently complicated with bloodstream infection (BSI). Complete device removal and prolonged antimicrobial therapy is essential for cure. The frequency of persistent BSI after source control (device extraction) is not well described. This study aims to assess the utility of repeat blood cultures (BC) after device extraction as recommended by the American Heart Association (AHA) guidelines. Methods: We selected patients who presented with BSI in the setting of CIED infection and underwent device removal at Mayo Clinic Rochester between 2012 and 2017. Cases where BC were not drawn prior to extraction, or repeated within 72 hours of device extraction, or met criteria for contamination were excluded. Results: Of 656 patients who underwent CIED extraction for device infection, 190 with post-extraction BC met study criteria. Among the final study cohort (Table 1), 159 patients had negative BC, while 31 had positive BC following CIED extraction. Pre-extraction, the most common causative organism was Staphylococcus aureus (91/190, 48%) (Figure 1a). Post-extraction, 22 of the 31 (71%) cases of persistent BSI were due to S. aureus (Fig 1b). The median duration of BSI was not significantly different between negative and positive BC groups (3 versus 4 days, p=0.92). Conclusions: Majority of patients had resolution of BSI after CIED extraction. S. aureus was the most common cause of persistent BSI post-extraction. Our findings support the AHA guidelines of repeating BC after device extraction, especially for S aureus .

Abstract Background Nocardial brain abscesses are rare, and published literature describing brain abscesses due to Nocardia species is limited to individual case reports or small series. We report one of the largest contemporary retrospective studies describing risk factors, diagnostic evaluation, management, and outcomes of nocardial brain abscess. Methods Retrospective review of all adults with brain abscess due to culture-confirmed Nocardia species at our institution between January 1, 2009, and June 30, 2020. Results Overall, 24 patients had nocardial brain abscesses during the study period. The median age at presentation was 64 years, and 62.5% were immunocompromised. Pulmonary and cutaneous infections were the most common primary sites of nocardial infection. All 24 patients had magnetic resonance imaging performed, and the frontal lobe was the most commonly involved. The most common organism isolated was Nocardia farcinica, followed by Nocardia wallacei and Nocardia cyriacigeorgica. Thirteen patients were managed with antimicrobial therapy alone, while 11 had both medical and surgical management. In all patients, dual therapy was recommended for the initial 6 weeks of treatment, and 22 patients received at least 1 oral agent as part of their final antibiotic regimen, predominantly trimethoprim-sulfamethoxazole and linezolid. Fourteen patients achieved complete clinical and radiographic resolution of infection. Conclusions Nocardia is an important cause of brain abscess in the immunocompromised host. Early diagnostic and therapeutic aspiration may help health care providers confirm the diagnosis, choose an appropriate antimicrobial regimen, and achieve source control.

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.

Abstract Background Accurate microbiologic diagnosis is important for appropriate management of infectious diseases. Sequencing-based molecular diagnostics are increasingly used for precision diagnosis of infections. However, their clinical utility is unclear. Methods We conducted a retrospective analysis of specimens that underwent 16S ribosomal RNA (rRNA) gene polymerase chain reaction (PCR) followed by Sanger sequencing at our institution from April 2017 through March 2019. Results A total of 566 specimens obtained from 460 patients were studied. Patients were considered clinically infected or noninfected based on final diagnosis and management. In 17% of patients, 16S rRNA PCR/sequencing was positive and in 5% of patients, this test led to an impact on clinical care. In comparison, bacterial cultures were positive in 21% of patients. Specimens with a positive Gram stain had 12 times greater odds of having a positive molecular result than those with a negative Gram stain (95% confidence interval for odds ratio, 5.2–31.4). Overall, PCR positivity was higher in cardiovascular specimens (37%) obtained from clinically infected patients, with bacterial cultures being more likely to be positive for musculoskeletal specimens (P < .001). 16S rRNA PCR/sequencing identified a probable pathogen in 10% culture-negative specimens. Conclusion 16S rRNA PCR/sequencing can play a role in the diagnostic evaluation of patients with culture-negative infections, especially those with cardiovascular infections.

Abstract Background A population-based study of infective endocarditis (IE) in Olmsted County, Minnesota, provides a unique opportunity to define temporal and seasonal variations in IE incidence over an extended time period. Methods This was a population-based review of all adults (≥18 years) residing in Olmsted County, Minnesota, with definite or possible IE using the Rochester Epidemiology Project from January 1, 1970, through December 31, 2018. Poisson regression was used to characterize the trends in IE incidence; models were fitted with age, sex, calendar time, and season, allowing for nonlinearity and nonadditivity of their effects. Results Overall, 269 cases of IE were identified over a 49-year study period. The median age of IE cases was 67.2 years, and 33.8% were female. The overall age- and sex-adjusted incidence of IE was 7.9 cases per 100 000 person-years (95% CI, 7.0–8.9), with corresponding rates of 2.4, 2.4, 0.9, and 0.7 per 100 000 person-years for Staphylococcus aureus, viridans group streptococci (VGS), Enterococcus species, and coagulase-negative staphylococci IE, respectively. Temporal trends varied by age, sex, and season, but on average IE incidence increased over time (P = .021). Enterococcal IE increased the most (P = .018), while S. aureus IE appeared to increase but mostly in the winter months (P = .018). Between 1996 and 2018, the incidence of VGS IE was relatively stable, with no statistically significant difference in the trends before and after the 2007 AHA IE prevention guidelines. Conclusions Overall, IE incidence, and specifically enterococcal IE, increased over time, while S. aureus IE was seasonally dependent. There was no statistically significant difference in VGS IE incidence in the periods before and after publication of the 2007 AHA IE prevention guidelines.

Background: SARS-CoV-2 infects its target cells via angiotensin converting enzyme 2 receptor, a membrane-bound protein found on the surface of many human cells. Treatment with angiotensin converting enzyme inhibitors (ACEI) or angiotensin receptors blockers (ARB) has been shown to increase angiotensin converting enzyme 2 expression by up to 5-fold. Areas of uncertainty: These findings coupled with observations of the high prevalence and mortality among SARS-CoV-2-infected patients with underlying cardiovascular disease have led to a speculation that ACEIs/ARBs may predispose to higher risk of being infected with SARS-CoV-2. Therefore, we systematically reviewed the literature and performed a meta-analysis of the association between prior use of ACEIs and ARBs and the risk of SARS-CoV-2 infection or hospitalization due to COVID-19 disease. Data sources: We searched Ovid MEDLINE(R) and Epub Ahead of Print, In-Process & Other Non-Indexed Citations and Daily, Ovid Embase, Ovid Cochrane Central Register of Controlled Trials, Ovid Cochrane Database of Systematic Reviews, Web of Science, Scopus, and Medrxiv.org preprint server until June 18, 2020. Therapeutic advances: Ten studies (6 cohorts and 4 case control) that enrolled a total of 23,892 patients and 853,369 controls were eligible for inclusion in our meta-analysis. One study was excluded from the analysis because of high risk of bias. Prior use of ACEIs was not associated with an increased risk of acquiring SARS-CoV-2 or hospitalization due to COVID-19 disease, odds ratio 0.98, 95% confidence interval (0.91–1.05), I2 = 15%. Similarly, prior use of ARBs was not associated with an increased risk of acquiring SARS-CoV-2, odds ratio 1.04, 95% confidence interval (0.98–1.10), I2 = 0%. Conclusion: Cumulative evidence suggests that prior use of ACEIs or ARBs is not associated with a higher risk of COVID-19 or hospitalization due to COVID-19 disease. Our results provide a reassurance to the public not to discontinue prescribed ACEIs/ARBs because of fear of COVID-19.

Abstract Background Brain abscess and cerebritis are diseases associated with high-risk morbidity and mortality despite the advancement of imaging technologies and antimicrobial therapy for the past 30 years. We aimed to describe the demographics of patients with brain abscess and cerebritis at Mayo Clinic. Methods We retrospectively reviewed the demographics of all adult patients with the diagnosis of intracranial brain abscess, cerebritis, or both at our institution from January 1, 2009, through December 31, 2019. All analyses were performed using JMP software (Cary, NC). Results A total of 666 patients with brain abscess and cerebritis were identified during the study period. The median patient age was 59.7 years, and the majority were males (64.8%; P=0.0001). A total of 587 (88.1%) patients self-identified as Whites (P=< 0.0001) and 608 (91.2%) as Non-Hispanic or Latino (P=< 0.0001). A total of 453 (68.01%) patients were from the Midwest, with Minnesota and Wisconsin being the two most common States with 243 (36.4%; P=< 0.0001) and 101 (15.1%; P=0.01) patients respectively. The majority of patients (69.2%) had coronary artery disease and peripheral vascular disease with a median Charlson comorbidity index of 7 (P= < 0.0001) and an estimated 10-year survival of 0%. Conclusion Male, White Non-Hispanics, and elderly patients seem to be the most prevalent patient population at risk for brain abscess or cerebritis. This investigation provides clinicians the demographic data needed to identify potentially complex patients with brain abscesses. Disclosures M. Rizwan Sohail, MD, Aziyo Biologics (Consultant)Medtronic Inc (Consultant, Research Grant or Support)

Abstract Background Transcatheter aortic valve replacement (TAVR) was initially approved as an alternative to surgery for patients at high surgical risk. However, it is now being considered for patients with intermediate and low surgical risk. This will result in the expansion of patient pool for TAVR; hence it is of interest to ascertain risk of blood stream infection (BSI) and infective endocarditis (IE) following TAVR. We aim to study the incidence, epidemiology and risk factors associated with IE in patients who underwent TAVR and subsequently developed a BSI. Methods A population-based study was conducted in 7 counties in southeastern Minnesota using the expanded Rochester Epidemiology Project (E-REP) for all adult (≥18 years) patients who underwent TAVR from January 1st, 2010 to December 31st, 2018. Transcatheter procedures that included replacement of either the aortic or mitral valve were included. Medical records were screened for development of BSI from time of TAVR until May 15th, 2020. Patients were classified as having BSI only, BSI with IE at outset, or BSI with subsequent development of new IE. ‘Early’ IE was defined as that occurring < 12 months following TAVR, with subsequent cases defined as ‘late’ IE. Results A total of 247 patients underwent TAVR during the study period. There were 24 patients with of BSI and 10 (42%) developed IE with an annual incidence of 5 per 1000 persons-years. Median age for patients who developed IE was 85.4 years. Male gender was affected predominantly (70%). Six developed IE at outset of BSI, while four developed IE subsequent to IE. The median time to development of IE was 791 days following TAVR. There was an equal number of early and late IE cases (n=5). The most common pathogen causing IE was viridians group streptococci (n=4) followed by enterococci and coagulase-negative staphylococci with 2 patients each. Mean Charlson comorbidity index was 6.6. Two patients with IE died before resolution of infection (20%). Conclusion The incidence of BSI and subsequent IE in patients with TAVR was low in our population. Due to the small number of BSI and IE cases, statistical analysis was not feasible. An analysis of all cases seen at Mayo Clinic is planned since the number of cases would be much higher to investigate potential risk factors associated with BSI and IE. Disclosures Larry M. Baddour, MD, Boston Scientific (Consultant) M. Rizwan Sohail, MD, Aziyo Biologics (Consultant)Medtronic Inc (Consultant, Research Grant or Support)