Bharath Raj Palraj

Predicting Risk of Endocarditis Using a Clinical Tool (PREDICT): Scoring System to Guide Use of Echocardiography in the Management of Staphylococcus aureus Bacteremia

BACKGROUND Infective endocarditis (IE) is a serious complication of Staphylococcus aureus bacteremia (SAB). There is limited clinical evidence to guide use of echocardiography in the management of SAB cases. METHODS Baseline and 12-week follow-up data of all adults hospitalized at our institution with SAB from 2006 to 2011 were reviewed. Clinical predictors of IE were identified using multivariable logistic regression analysis. RESULTS Of the 757 patients screened, 678 individuals with SAB (24% community acquired, 56% healthcare associated, and 20% nosocomial) met study criteria. Eighty-five patients (13%) were diagnosed with definite IE within the 12 weeks of initial presentation based on modified Duke criteria. The proportion of patients with IE was 22% (36/166) in community-acquired SAB, 11% (40/378) in community-onset healthcare-associated SAB, and 7% (9/136) in nosocomial SAB. Community-acquired SAB, presence of cardiac device, and prolonged bacteremia (≥ 72 hours) were identified as independent predictors of IE in multivariable analysis. Two scoring systems, day 1 (SAB diagnosis day) and day 5 (when day 3 culture results are known), were derived based on the presence of these risk factors, weighted in magnitude by the corresponding regression coefficients. A score of ≥ 4 for day 1 model had a specificity of 96% and sensitivity of 21%, whereas a score of <2 for day 5 model had a sensitivity of 98.8% and negative predictive value of 98.5%. CONCLUSIONS We propose 2 novel scoring systems to guide use of echocardiography in SAB cases. Larger prospective studies are needed to validate the classification performance of these scoring systems.

Clinical Presentation, Risk Factors, and Outcomes of Hematogenous Prosthetic Joint Infection in Patients with Staphylococcus aureus Bacteremia

BACKGROUND Staphylococcus aureus bacteremia is a life-threatening condition that may lead to metastatic infection, including prosthetic joint infection. METHODS To assess clinical factors associated with hematogenous prosthetic joint infection, we retrospectively reviewed all patients with a joint arthroplasty in place at the time of a first episode of S. aureus bacteremia over a 5-year period at our institution. Patients with postsurgical prosthetic joint infection without hematogenous prosthetic joint infection were excluded. RESULTS There were 85 patients (143 arthroplasties) with either no prosthetic joint infection (n = 50; 58.8%) or hematogenous prosthetic joint infection in at least one arthroplasty (n = 35; 41.2%). The odds of hematogenous prosthetic joint infection was significantly increased among patients with community-acquired S. aureus bacteremia (odds ratio [OR] 18.07; 95% confidence interval [CI] 2.64-infinity; P = .001), as compared with nosocomial S. aureus bacteremia, in which there were no patients with hematogenous prosthetic joint infection. After adjusting for S. aureus bacteremia classification, the presence of ≥3 joint arthroplasties in place was associated with a nearly ninefold increased odds of hematogenous prosthetic joint infection as compared with those with 1-2 joint arthroplasties in place (OR 8.55; 95% CI 1.44-95.71; P = .012). All but one joint with prosthetic joint infection demonstrated at least one clinical feature suggestive of infection. There were 4 additional S. aureus prosthetic joint infections diagnosed during a median of 3.4 years of follow-up post hospitalization for S. aureus bacteremia. CONCLUSION Prosthetic joint infection is frequent in patients with existing arthroplasties and concomitant S. aureus bacteremia, particularly with community-acquired S. aureus bacteremia and multiple prostheses. In contrast, occult S. aureus prosthetic joint infection without clinical features suggestive of prosthetic joint infection at the time of S. aureus bacteremia is rare.

Predicting Risk of Endovascular Device Infection in Patients With Staphylococcus aureus Bacteremia (PREDICT-SAB)

Background—Prompt recognition of underlying cardiovascular implantable electronic device (CIED) infection in patients presenting with Staphylococcus aureus bacteremia (SAB) is critical for optimal management of these cases. The goal of this study was to identify clinical predictors of CIED infection in patients presenting with SAB and no signs of pocket infection. Methods and Results—All cases of SAB in CIED recipients at Mayo Clinic from 2001 to 2011 were retrospectively reviewed. We identified 131 patients with CIED who presented with SAB and had no clinical signs of device pocket infection. Forty-five (34%) of these patients had underlying CIED infection based on clinical or echocardiographic criteria. The presence of a permanent pacemaker rather than an implantable cardioverter-defibrillator (odds ratio, 3.90; 95% confidence interval, 1.65–9.23; P=0.002), >1 device-related procedure (odds ratio, 3.30; 95% confidence interval, 1.23–8.86; P=0.018), and duration of SAB ≥4 days (odds ratio, 5.54; 95% confidence interval, 3.32–13.23; P<0.001) were independently associated with an increased risk of CIED infection in a multivariable model. The area under the receiver operating characteristics curve for the multivariable model was 0.79, indicating a good discriminatory capacity to distinguish SAB patients with and without CIED infection. Conclusions—Among patients presenting with SAB and no signs of pocket infection, the risk of underlying CIED infection can be calculated based on the type of device, number of device-related procedures, and duration of SAB. We propose that patients without any of these high-risk features have a low risk of underlying CIED infection and may be monitored closely without immediate device extraction. Prospective studies are needed to validate this risk prediction model.

Appropriate use of echocardiography in managing Staphylococcus aureus bacteremia

Staphylococcus aureus bacteremia (SAB) is increasing, both in the community and in healthcare settings. Accurate and timely diagnosis of underlying infective endocarditis (IE) is critical for optimal management of SAB cases as it has significant management and prognostic implications. Reported prevalence of IE in patients with SAB varies depending on the study population, and ranges from 10 to 30%. As clinical presentation of IE can be nonspecific, echocardiography is usually recommended in SAB cases to ‘rule out’ IE. Due to its poor sensitivity (<50%), especially for diagnosing prosthetic valve IE, transthoracic echocardiography is considered inadequate in this setting and clinicians have to rely on transesophageal echocardiography (TEE) to confirm or exclude endocarditis in SAB cases. Although some experts recommend TEE in all patients presenting with SAB, it is believed that the use of TEE could be guided by individual patient risk factors, mode of acquisition of SAB and clinical presentation. In this article, published data regarding the use of TEE in the SAB population are reviewed and a simplified algorithm to guide use of TEE in SAB cases is proposed.

Streptococcus gordonii prosthetic joint infection in the setting of vigorous dental flossing

A 65-year-old woman with osteoarthritis, who underwent knee replacement 5 years prior, developed sudden onset knee pain and swelling. She had voluntarily starting a vigorous dental flossing regimen prior to the onset of symptoms. The patient underwent right knee arthrotomy, irrigation and debridement of right total knee arthroplasty and exchange of polyethylene with retention of the prosthesis. Intraoperative cultures grew Streptococcus gordonii. She was treated with 6 weeks of ceftriaxone and was later placed on oral antibiotic suppression.

Lactobacillus gasseri Causing Bilateral Empyema

Lactobacilli are common commensal bacteria found in the gastrointestinal and genitourinary tract. Although they are usually thought to be nonpathogenic, there have been several cases that demonstrate severe infections caused by these microorganisms. This is a case of a 49-year-old male with previously undiagnosed type two diabetes mellitus who presented with a 3-month history of cough and was found to have right sided Lactobacillus gasseri empyema for which he underwent video-assisted thoracoscopic surgery (VATS) with chest tube placement. He subsequently developed a left sided pleural empyema for which the aspiration also grew out L. gasseri. The patient made a complete recovery and was seen for four months in follow-up after his initial presentation.

Clostridium hathewayi bacteraemia and surgical site infection after uterine myomectomy

A 42-year-old woman with uterine fibroids underwent myomectomy. She developed postoperative sepsis and bloodstream infection with Clostridium hathewayi secondary to an infected haematoma. The patient was readmitted after failure of oral antibiotic therapy and underwent intrauterine drainage followed by prolonged parenteral antibiotic therapy. The patient was followed for 1 year and did not have any relapse of infection.

Mycobacteria in the Literature: Report 03-2016

h 2 Randomized Trial of Liposomal Amikacin for Inhalation in Nonuberculous Mycobacterial Lung disease Olivier KN, Griffith DE, Eagle G, McGinnis Ii JP, Micioni L, Liu , Daley CL, Winthrop KL, Ruoss S, Addrizzo-Harris DJ, Flume PA, organ D, Salathe M, Brown-Elliott BA, Gupta R, Wallace RJ Jr. Ranomized Trial of Liposomal Amikacin for Inhalation in Nontubercuous Mycobacterial Lung disease. Am J Respir Crit Care Med. 2016 ct 17. DOI: 10.1164/rccm.201604–0700OC. Pulmonary nontuberculous mycobacterial infection is a complex isease process that can result in progressive lung damage charcterized by necrotizing inflammation, bronchiectasis and cavitory esions. The resultant irreversible damage can impair pulmonary unction and increase mortality. Treatment of patients with pulonary nontuberculous mycobacterial (NTM) infections involves rolonged duration of multiple antibiotics that are limited by poor fficacy, toxicities and intolerance. Newer drugs and or delivery ethods that increase tolerance and reduce systemic toxicities re needed to improve management of these complex patients. In his multicenter clinical trial, investigators studied the efficacy and afety of liposomal amikacin for inhalation in patients who have ersistently positive cultures for NTM despite at least 6 months f appropriate multidrug antibiotic regimens as recommended in uidelines. In this phase 2 double blind, placebo-controlled study, investiators randomly assigned 90 patients to liposomal amikacin for inalation (LAI) or placebo once daily in addition to their guidelineased multi-drug regimens for 84 days, followed by open label adinistration of LAI to both groups for additional 84 days. Patients ith history of active smoking, forced expiratory volume in 1 s of ess than 30%, clinically significant heart, lung, liver or kidney disase, systemic immune deficiency, and malignancy were excluded. he primary end point was change in semi-quantitative scale (to ssess relative mycobacterial growth) from baseline day 84.

Strategies to Prevent Infections Associated with Cardiovascular Implantable Electronic Devices.

ABSTRACT Introduction: Infections involving cardiovascular implantable electronic devices (CIED) are associated with high morbidity and mortality and substantial financial cost. In the past two decades, the rate of CIED infections has increased disproportionate to the number of devices implanted, likely due to aging patient population with multiple comorbidities. Microbial contamination of the generator pocket and or leads by skin flora at the time of implantation is a major mechanism for early CIED infections. Due to resistance to host immune cells and antibiotics caused by biofilm formation, complete removal of the device generator and leads is required to achieve cure. Areas covered: In this manuscript, we review the published literature regarding epidemiology, risk factors, and pathogenesis of CIED infections with primary focus on the preventative strategies to reduce the incidence of device infections. Expert commentary: Strict adherence to infection control measures at the time of CIED implantation is critical in reducing the risk of device infection while adjunctive strategies such as use of antimicrobial envelopes might help in certain high-risk individuals. Technological advances in device manufacturing with availability of subcutaneous devices without transvenous leads and self-contained intracardiac devices without leads and generator show promise with lower risk of infection.

Actinomyces meyeri Popliteal Cyst Infection and Review of the Literature

A 66-year-old, Caucasian male presented with pain and swelling involving the left knee of one-week duration. Arthrocentesis was negative for evidence of septic arthritis. Magnetic resonance imaging (MRI) study of the left knee showed degenerative arthritis, partial tear of medial meniscus, and a complex fluid collection along the posteromedial aspect of the left knee suggestive of popliteal cyst. He underwent arthroscopy with partial medial meniscectomy. Intraoperative joint fluid was noted to be cloudy but cultures were negative. Arthroscopic procedure provided him with temporary relief but the pain and swelling in the posterior aspect of the left knee recurred in 6 weeks. Repeat MRI showed complex fluid collection in the posterolateral aspect of left knee. Ultrasound guided aspiration of the fluid collection revealed purulent material and cultures grew Actinomyces meyeri. He was treated with 6 weeks of intravenous penicillin regimen followed by 18 months of oral penicillin.