Infective endocarditis in intravenous drug abusers: an update. Eur J Clin Microbiol Infect Dis. 2012;31:2905-2910. [PMID: 22714640 DOI: 10.1007/s10096-012-1675-x]

Bacteraemia with gram-positive bacteria-when and how do I need to look for endocarditis?

BACKGROUND

Patients with bacteraemia caused by gram-positive bacteria are at risk for infective endocarditis (IE). Because IE needs long antibiotic treatment and sometimes heart valve surgery, it is very important to identify patients with IE.

OBJECTIVES

In this narrative review we present and discuss how to determine which investigations to detect IE that are needed in individual patients with gram-positive bacteraemia.

SOURCES

Published original studies and previous reviews in English, within the relevant field are used.

CONTENT

First, the different qualities of the bacteraemia in relation to IE risk are discussed. The risk for IE in bacteraemia is related to the species of the bacterium but also to monomicrobial bacteraemia and the number of positive cultures. Second, patient-related factors for IE risk in bacteraemia are presented. Next, the risk stratification systems to determine the risk for IE in gram-positive bacteraemia caused by Staphylococcus aureus, viridans streptococci, and Enterococcus faecalis are presented and their use is discussed. In the last part of the review, an account for the different modalities of IE-investigations is given. The main focus is on echocardiography, which is the cornerstone of IE-investigations. Furthermore, 18F-fluorodesoxyglucose positron emission tomography/computed tomography and cardiac computed tomography are presented and their use is also discussed. A brief account for investigations used to identify embolic phenomena in IE is also given. Finally, we present a flowchart suggesting which investigations to perform in relation to IE in patients with gram-positive bacteraemia.

IMPLICATIONS

For the individual patient as well as the healthcare system, it is important both to diagnose IE and to decide when to stop looking for IE. This review might be helpful in finding that balance.

Epidemiological Changes and Improvement in Outcomes of Infective Endocarditis in Europe in the Twenty-First Century: An International Collaboration on Endocarditis (ICE) Prospective Cohort Study (2000-2012)

INTRODUCTION

Infective endocarditis (IE) has undergone important changes in its epidemiology worldwide.

METHODS

The study aimed to compare IE epidemiological features and outcomes according to predefined European regions and between two different time periods in the twenty-first century.

RESULTS

IE cases from 13 European countries were included. Two periods were considered: 2000-2006 and 2008-2012. Two European regions were considered, according to the United Nations geoscheme for Europe: Southern (SE) and Northern-Central Europe (NCE). Comparisons were performed between regions and periods. A total of 4195 episodes of IE were included, 2113 from SE and 2082 from NCE; 2787 cases were included between 2000 and 2006 and 1408 between 2008 and 2012. Median (IQR) age was 63.7 (49-74) years and 69.4% were males. Native valve IE (NVE), prosthetic valve IE (PVE), and device-related IE were diagnosed in 68.3%, 23.9%, and 7.8% of cases, respectively; 52% underwent surgery and 19.3% died during hospitalization. NVE was more prevalent in NCE, whereas device-related IE was more frequent in SE. Higher age, acute presentation, hemodialysis, cancer, and diabetes mellitus all were more prevalent in the second period. NVE decreased and PVE and device-related IE both increased in the second period. Surgical treatment also increased from 48.7% to 58.4% (p < 0.01). In-hospital and 6-month mortality rates were comparable between regions and significantly decreased in the second period.

CONCLUSIONS

Despite an increased complexity of IE cases, prognosis improved in recent years with a significant decrease in 6-month mortality. Outcome did not differ according to the European region (SE versus NCE).

Isolated pulmonary valve endocarditis with pulmonary annular abscess in a patient of Noonan syndrome

Right-sided endocarditis is a rare entity, with various series reporting an incidence of 5%–10%. Pulmonary valve (PV) is not only the least commonly involved valve in infective endocarditis (IE), with an incidence of 1.5%–2%, but ‘isolated’ pulmonic valve endocarditis (PVE) without tricuspid valve involvement is even rarer with limited published data. We report a middle-aged man with Noonan syndrome and a dysplastic PV with severe pulmonary stenosis. He presented with a large isolated mobile PV vegetation with moderate pulmonary regurgitation (PR). Initially, he was managed conservatively, but due to persistent fever, pulmonary regurgitation and evidence of pulmonary annular abscess extending into the right ventricular outflow tract, he required surgical intervention. Considering the low incidence of isolated PVE, it poses a challenge for physicians in prompt diagnosis and timely management of the infection.

Epidemiologic and clinical characteristics of infective endocarditis: a single-center retrospective study in the Bronx, New York

OBJECTIVE

There is paucity of data on the epidemiological, microbiological, and clinical characteristics of patients admitted with infective endocarditis (IE) in the Bronx, New York.

PATIENT AND METHODS

We conducted a retrospective study at Jacobi Medical Center, a tertiary care hospital in the Bronx. All adult patients who were hospitalized with a primary diagnosis of new-onset IE between January 1st, 2010 and September 30th, 2020 were included. The primary outcome was in-hospital mortality. A logistic regression model was used to identify baseline variables associated with in-hospital mortality.

RESULTS

182 patients were included in this analysis (female sex: 38.5%, median age: 54 years). 46 patients (25.3%) reported intravenous drug use. 153 patients (84.1%) had positive blood cultures. Staphylococcus aureus (S. aureus) was the most common isolated pathogen (45.1% of monomicrobial IE). Nearly half of the cases secondary to S. aureus were methicillin resistant Staphylococcus aureus (MRSA) (34/69). 164 patients (90.1%) were diagnosed with native valve IE. The mitral valve was involved in 32.4% of patients followed by the aortic valve (19.8%). The in-hospital mortality was 18.1%. The mortality was higher in the cohort 2010-2015 compared to the cohort 2016-2020 (22.1% vs 14.6%). Increasing age, MRSA IE, and active malignancy were the only variables found to have significant association with in-hospital death.

CONCLUSION

S. aureus was the most common causative agent and MRSA accounted for about half of the S. aureus IE cases. The incidence of IE in patients with intravenous drug use increased over time, while the median age decreased. The in-hospital death rate was higher in 2010-2015 compared to 2016-2020.

OUP accepted manuscript

Enterobacter cloacae are a rare cause of infective endocarditis (IE). We present an interesting case of a 51-year-old intravenous drug user with E. cloacae IE of a prosthetic aortic valve and a fistula into the right ventricle. He underwent surgical repair and 6 weeks of intravenous meropenem.

Phalloplasty Complicated by Penile Artery Thrombosis, Recurrent Extended-Spectrum Beta-Lactamase (ESBL) Urinary Tract Infection (UTI), Colovesical Fistula, and Enterococcus Faecalis Endocarditis

Enterococcus faecalis is an enteric microorganism that, if introduced into the vasculature, is an uncommon cause of infective endocarditis. Timely diagnosis, appropriate treatment measures, and close follow-up are key to therapeutic success. Antibiotic therapy is the mainstay of therapy, and surgical intervention is sometimes indicated. Here we present a novel case of a 45-year-old transgender male with Factor V Leiden deficiency who was found to have Enterococcus faecalis mitral valve endocarditis due to the postoperative complications of colovesical fistula formation leading to extended-spectrum beta-lactamase (ESBL) urinary tract infection (UTI) and E. faecalis bacteremia in the setting of recent phalloplasty, mastectomy, and vaginal eversion.

Association of a Substance Use Disorder with Infectious Diseases among Adult Home Healthcare Patients with a Venous Access Device

Substance use disorders (SUDs) and high incidence of infectious diseases are both critical public health issues. Among patients who use a venous access device (VAD) in home care settings, SUDs may play a role in increasing their risk of having a concurrent infectious disease. This study examined the association of SUD with infectious diseases among adult home healthcare patients with a VAD. We identified adult patients with an existing VAD who were admitted to a home healthcare agency August 1, 2017-July 31, 2018 from the electronic health records of a large Medicare-certified agency. Four serious infectious diseases (endocarditis, epidural abscess, septic arthritis, and osteomyelitis) and SUD related to injectable drugs were identified using relevant ICD-10 codes. Multiple logistic regression was performed to examine the association. Of 416 patients with a VAD, 12% (n = 50) had at least one diagnosis of a serious infectious disease. The percentage of patients who had a serious infectious disease was 40% among those with SUDs, compared with only 11% among those without SUDs. After adjusting for age and sex, the odds of having a serious infectious disease was 3.52 times greater for those with SUDs compared with those without (odds ratio [95% confidence interval], 4.52 [1.48-13.79], n = .008). Our findings suggest that home healthcare patients with a VAD and a documented SUD diagnosis may have an increased risk of having a concurrent serious infectious disease. Therefore, patients with an SUD and a VAD would need more attention from home healthcare providers to prevent a serious infectious disease. Further research is suggested on modalities of care for individuals with an SUD and VAD to reduce the incidence of infectious diseases so that care can be delivered safely and efficiently in a home healthcare setting.

An unusual case of infective endocarditis with acute limb ischemia and cardiac embolism

Infective endocarditis (IE) is a persistent health issue, particularly among intravenous drug users. We discussed a case of infective endocarditis in a patient who uses IV drugs, which had some unusual features such as unusual presentation, polymicrobial infection, left-sided valve involvement, coronary embolism, and an uncommon pathogen for IE.

Burden of infective endocarditis in an Australian cohort of people who inject drugs

BACKGROUND

Infective endocarditis (IE) results in substantial morbidity and mortality in people who inject drugs (PWID).

AIMS

To describe the burden of IE and its outcomes in PWID.

METHODS

Retrospective cohort study of adults admitted to a tertiary referral centre in Melbourne, Australia, with IE due to injection drug use from 1997 to 2015.

RESULTS

Ninety-seven PWID with 127 episodes of IE were identified with a median acute inpatient stay of 37 days (1-84). Admission to an intensive care unit was required in 67/127 (53%) episodes. Twenty-seven percent (34/127) of episodes occurred in patients with a previous episode of endocarditis. One third (43/127, 34%) of episodes involved left-sided cardiac valves. Antimicrobial treatment was completed in 88 (70%) episodes. Valve surgery was performed in 25/127 (20%) episodes. Predictors of surgery in univariable analysis were left-sided cardiac involvement (risk ratio (RR) 6.0), severe valvular regurgitation (RR 2.6) and cardiac failure (RR 2.2) (all P < 0.005). Twenty (16%) episodes resulted in death. Predictors of mortality on univariable analysis were left-sided cardiac involvement (RR 6.4), and not completing treatment (RR 0.12; both P < 0.001). The average estimated cost per episode was AU$74 168.

CONCLUSIONS

IE causes a considerable burden of disease in PWID, with significant healthcare utilisation and cost. Surgery and death are not infrequent complications. In addition to ensuring completion of antimicrobial therapy, strategies such as opioid maintenance programmes may be useful in improving health outcomes for PWID.

Vitreous and Chorioretinal Lesions in People Who Inject Drugs and Are Hospitalized with Bloodstream and Related Infections

PURPOSE

To determine the prevalence of and to characterize vitreous and chorioretinal lesions, to identify causative organisms, and to correlate symptoms with ophthalmic involvement in people who inject drugs and are hospitalized with bloodstream infection (BSI), related metastatic foci of infection (MFI), or both.

DESIGN

An academic hospital-based cross-sectional study.

PARTICIPANTS

Patients admitted with BSI or MFI related to injection drug use (IDU).

METHODS

Patients underwent a complete eye examination within 72 hours of enrollment. Characteristics including gender; age; race; injection drug of choice (DOC); presence of coinfection with hepatitis B, hepatitis C, or human immunodeficiency virus; pathogen causing systemic infection and type of infection; and history of prior infection related to IDU were recorded.

MAIN OUTCOME MEASURES

Presence of vitreous or chorioretinal findings, or both.

RESULTS

Ninety-one unique patients with 96 separate hospitalizations for systemic infection were enrolled from March 28, 2018, through March 30, 2020. Vitreous or chorioretinal involvement was identified in 16 of 96 patients (16.7%). The most common ocular findings were intraretinal or white-centered hemorrhage in 9 of 96 patients, chorioretinal infiltrate in 8 of 96 patients, endophthalmitis in 5 of 96 patients, and cotton wool spots in 3 of 96 patients. Of the patients with ocular involvement, only 7 of 16 patients (44%) were symptomatic, and 5 of these were patients with endophthalmitis; the others showed chorioretinal infiltrates or intraretinal or white-centered hemorrhage and cotton wool spots. Staphylococcus aureus was the most common causative pathogen in patients with and without ocular findings. Presence of ocular symptoms, worse visual acuity, and injection DOC of methamphetamine were correlated with the presence of ocular findings.

CONCLUSIONS

Patients without ocular symptoms with systemic infections related to IDU may have chorioretinal findings. Further study is needed to characterize better the epidemiologic features of these infections and to identify risk factors for ocular involvement in people who inject drugs.

Patients with infective endocarditis and history of injection drug use in a Swedish referral hospital during 10 years

Background

Patients with injection drug use (IDU) have increased risk of developing infective endocarditis (IE). Previous studies have reported recurrent IE, increased duration of hospital stay, poor adherence and compliance as well as higher mortality and worse outcomes after surgery in the IDU-IE patient group. Further studies are needed to provide a basis for optimized care and prevention of readmissions in this population. This study aims to describe the clinical characteristics and outcomes among patients with IDU-IE.

Methods

Data of adults with IDU-IE and non-IDU-IE, treated between 2008 and 2017 at the Karolinska University Hospital in Stockholm were obtained from the Swedish National Registry of Infective Endocarditis. Clinical characteristics, microbiological results, treatment durations, results from echocardiography and in-hospital mortality were compared between the groups.

Results

Of the total 522 patients, 165 (32%) had IDU-IE. Patients with IDU-IE were younger than the patients with non-IDU-IE (mean age IDU-IE: 41.6 years, SD 11.9 years; non-IDU-IE: 64.3 years, SD 16.4 years; P <  0.01). No difference in distribution of gender was observed, 33% were females in both the IDU-IE and the non-IDU-IE group. History of previous IE (IDU-IE: n = 49, 30%; non-IDU-IE: n = 34, 10%; P <  0.01) and vascular phenomena (IDU-IE: n = 101, 61%; non-IDU-IE: n = 120, 34%; P <  0.01) were more common among patients with IDU-IE while prosthetic heart valves (IDU-IE: n = 12, 7%; non-IDU-IE: n = 83, 23%; P <  0.01) and known valvular disease (IDU-IE: n = 3, 2%; non-IDU-IE: n = 78, 22%; P <  0.01) were more common among patients with non-IDU-IE. Aetiology of Staphylococcus aureus (IDU-IE: n = 123, 75%; non-IDU-IE: n = 118, 33%; P <  0.01) as well as tricuspid (IDU-IE: n = 91, 55%; non-IDU-IE: n = 23, 6%; P <  0.01) or pulmonary valve vegetations (IDU-IE: n = 7, 4%; non-IDU-IE: n = 2, 1%; P <  0.01) were more common in the IDU-IE group. The overall incidence of IDU-IE decreased during the study period, while the incidence of definite IE increased (P <  0.01).

Conclusions

This study presents that patients with IDU-IE were younger, less frequently treated with surgery and had higher prevalence of vascular phenomena and history of previous IE, aspects that are important for improved management of this population.

Risk factors of infective endocarditis in persons who inject drugs

BACKGROUND

The rising incidence of infective endocarditis (IE) among people who inject drugs (PWID) has been a major concern across North America. The coincident rise in IE and change of drug preference to hydromorphone controlled-release (CR) among our PWID population in London, Ontario intrigued us to study the details of injection practices leading to IE, which have not been well characterized in literature.

METHODS

A case-control study, using one-on-one interviews to understand risk factors and injection practices associated with IE among PWID was conducted. Eligible participants included those who had injected drugs within the last 3 months, were > 18  years old and either never had or were currently admitted for an IE episode. Cases were recruited from the tertiary care centers and controls without IE were recruited from outpatient clinics and addiction clinics in London, Ontario.

RESULTS

Thirty three cases (PWID IE+) and 102 controls (PWID but IE-) were interviewed. Multivariable logistic regressions showed that the odds of having IE were 4.65 times higher among females (95% CI 1.85, 12.28; p = 0.001) and 5.76 times higher among PWID who did not use clean injection equipment from the provincial distribution networks (95% CI 2.37, 14.91; p < 0.001). Injecting into multiple sites and heating hydromorphone-CR prior to injection were not found to be significantly associated with IE. Hydromorphone-CR was the most commonly injected drug in both groups (90.9% cases; 81.4% controls; p = 0.197).

DISCUSSION

Our study highlights the importance of distributing clean injection materials for IE prevention. Furthermore, our study showcases that females are at higher risk of IE, which is contrary to the reported literature. Gender differences in injection techniques, which may place women at higher risk of IE, require further study. We suspect that the very high prevalence of hydromorphone-CR use made our sample size too small to identify a significant association between its use and IE, which has been established in the literature.

The epidemiology of infective endocarditis with focus on non-device related right-sided infective endocarditis: A retrospective register-based study in the region of Southern Denmark

AIMS

Non-device related right-sided infective endocarditis (ND-RSIE) is not well characterized. We aimed to characterize patients with infective endocarditis (IE) with emphasis on the epidemiology, clinical characteristics and complications of ND-RSIE.

METHODS

In this population-based cohort study, we identified patients with IE using ICD-10 codes from the Danish National Hospital Register in the Region of Southern Denmark between January 2007 and May 2017. Hospital records were reviewed, and characteristics and outcomes recorded.

RESULTS

We included 1243 confirmed IE episodes of which 82% were left-sided IE, 11% were cardiac device right sided infective endocarditis (RSIE) and 7% were ND-RSIE. Patients with ND-RSIE were considerably younger, had less comorbidity and had a lower 30-day mortality (6%) compared with patients with device RSIE (24%) and left-sided IE (26%) (p<0.01). ND-RSIE was associated with underlying heart disease, involvement of the tricuspid valve (57%), Staphylococcus species (53%) and complications (61%). Forty percent of ND-RSIE occurred among people who inject drugs (PWID) for whom significant differences were observed compared with non-PWID with regards to tricuspid valve involvement (96% vs. 32%), causative microorganisms (Staphylococcus aureus 79% vs. 27%), complications (86% vs. 45%), recurrence (29% vs. 11%) and 30-day mortality (0% vs. 7%).

CONCLUSION

ND-RSIE is relatively rare and differs with regards to epidemiology, clinical characteristics and complications compared with left-sided IE and cardiac device RSIE, but has a favourable prognosis. Forty percent of ND-RSIE occurs among PWID, which is associated with frequent complications but a very low mortality.

Candida spp./Bacteria Mixed Biofilms

The ability to form biofilms is a common feature of microorganisms, such as bacteria or fungi. These consortiums can colonize a variety of surfaces, such as host tissues, dentures, and catheters, resulting in infections highly resistant to drugs, when compared with their planktonic counterparts. This refractory effect is particularly critical in polymicrobial biofilms involving both fungi and bacteria. This review emphasizes Candida spp.-bacteria biofilms, the epidemiology of this community, the challenges in the eradication of such biofilms, and the most relevant treatments.

Associations between echocardiographic manifestations and bacterial species in patients with infective endocarditis: a cohort study

Background

The diagnosis of infective endocarditis (IE) is based on microbiological analyses and diagnostic imaging of cardiac manifestations. Echocardiography (ECHO) is preferred for visualization of IE-induced cardiac manifestations. We investigated associations between bacterial infections and IE manifestations diagnosed by ECHO.

Methods

In this cohort study, data from patients aged 18 years or above, with definite IE admitted at the Karolinska University Hospital between 2008 and 2017 were obtained from Swedish National Registry of Endocarditis. Bacteria registered as pathogen were primarily selected from positive blood culture and for patients with negative blood culture, bacteria found in culture or PCR from postoperative material was registered as pathogen. Patients with negative results from culture or PCR, and patients who did not undergo ECHO during hospital stay, were excluded. IE manifestations diagnosed by ECHO were obtained from the registry. Chi-squared test and two-sided Fisher’s exact test was used for comparisons between categorical variables, and student’s t test was used for continuous numerical variables. Multivariable analyses were performed using logistic regression. Secular trend analyses were performed using linear regression. Associations and the strength between the variables were estimated using odds ratios (ORs) with 95% confidence intervals (CIs). P < 0.05 was considered significant.

Results

The most common bacteria were Staphylococcus aureus (n = 239, 49%) and viridans group streptococci (n = 102, 21%). The most common manifestations were vegetation in the mitral (n = 195, 40%), aortic (n = 190, 39%), and tricuspid valves (n = 108, 22%). Associations were seen between aortic valve vegetations and Enterococcus faecalis among patients with native aortic valves, between mitral valve vegetations and streptococci of group B or viridans group, between tricuspid valve vegetations and S. aureus among patients with intravenous drug abuse, and between perivalvular abscesses as well as cardiovascular implantable electronic device (CIED)-associated IE and coagulase negative staphylococci (all P < 0.05).

Conclusions

Associations were found between certain bacterial species and specific ECHO manifestations. Our study contributes to a better understanding of IE manifestations and their underlying bacterial etiology, which pathogens can cause severe infections and might require close follow-up and surgical treatment.

A changing profile of infective endocarditis at a tertiary hospital in China: a retrospective study from 2001 to 2018

Background

Infective endocarditis (IE) is a lethal disease which has been changing significantly over the past decades; however, information about IE in China remains scarce. This study surveyed the changes in clinical characteristics of IE at a tertiary hospital in south China over a period of nearly 18 years.

Methods

Medical records with IE patients consecutively hospitalized between June 2001 and June 2018 were selected from the electronic medical records system in Nanfang Hospital of Southern Medical University. Data were divided by admission time into two groups equally: early-period group, June 2001 to December 2009 and later-period group, January 2010 to July 2018.

Results

A Total of 313 IE patients were included in our study. Compared with the early-period group, patients in the later-period group included fewer intravenous drug users (IVDUs), older age at onset, reduced development of pulmonary embolism, less renal dysfunction, decreased proportion of Staphylococcus aureus infection and fewer vegetations observed in the right heart by echocardiography. The later-period group also showed a higher proportion of ischemic strokes and higher proportion of positive microbiological findings compared with the early-period group. The in-hospital mortality remained about the same between the two periods and the multivariate analysis identified intravenous drug addicted, prosthetic valve endocarditis, hemorrhagic stroke, acute congestive heart failure, renal insufficiency, left-sided endocarditis, early surgical as independent predictors of in-hospital mortality.

Conclusions

Our study demonstrated a dramatic change in the profile of IE over a period of 18 years at a tertiary hospital in south China and presented several independent predictors of in-hospital mortality. The geographic variations observed in our study will be of important value to profile the clinical feature of China and offer the reference for clinical decisions in our region.

Tricuspid and Pulmonic Valve Pathology

PURPOSE OF REVIEW

This review describes the normal structure and pathologic changes that affect the right-sided cardiac valves and chambers.

RECENT FINDINGS

The anatomy and pathology described have been known for many years. Knowledge of these findings has gained relevance. The pattern of endocarditis is changing. New diagnostic techniques have allowed better characterization of lesions responsible for cardiac dysfunction. Novel, less invasive interventions have made recognition of abnormalities more clinically relevant. There are many different pathologic entities that can affect the right-sided cardiac valves. These are discussed in this review.

[Infective endocarditis and specific situations: Right heart, valve prosthesis, cardiac implantable electronic device]

Right-sided infective endocarditis (IE) represents 5-10% of IE. It may occur in patients with electronic intracardiac device, central venous catheter or congenital heart disease, but the most frequent situation is intravenous drug use. Prosthetic valve IE is the most severe form of IE. The diagnosis is more challenging than that of native valve IE, as is treatment, both antibiotic treatment and surgical indications. The infection of an electronic intracardiac device is a severe disease. Both diagnostic and therapeutic strategies are difficult.

Eustachian valve infective endocarditis

A 40-year-old woman presented with postoperative fever. Echocardiography revealed a large pedunculated cauliflower right atrial mass of heterogeneous echogenicity attached to the eustachian valve measuring about 2×3 cm. She underwent surgical excision, gross and microscopical examination were consistent with eustachian valve infective endocarditis.

Increasing incidence of IV-drug use associated endocarditis in southern West Virginia and potential economic impact

BACKGROUND

The opioid crisis has disproportionally affected Appalachia. One of the potentially lethal and costly complications associated with IV drug use is infective endocarditis (IE). The goal of this study was to assess the trend and costs of substance abuse associated IE admissions in Southern West Virginia.

METHODS

This is a retrospective analysis of cost, incidence, and geographic patterns of all patients admitted over the last decade with concomitant drug abuse (cocaine, amphetamine, sedative, and other/mixed drug abuse) and IE in the largest tertiary care center for Southern West Virginia. A time series model was used to investigate the effect of drug use on the incidence of IE.

RESULTS

A total of 462 patients were hospitalized with IE and concomitant illicit drug use. IE cases increased from 26 admissions in 2008 to 66 in 2015. Patterns of increases in mixed drug use (DRG most often associated with IV drug use in our center) mirrored increases in IE (P = 0.001). From 2008 to 2015, the total hospital charges were $17 306 464 on 462 cases of illicit drug associated IE. Only a fraction of the billed fees (22%) was collected ($3 829 701).

CONCLUSIONS

The number of patients hospitalized with IE has dramatically increased over the last decade in a pattern that mirrors the increase in mixed drug use. The majority of payers were from underfunded state programs or private pay and thus, only 22% of the hospital charges were paid, leaving a hospital deficit of over $13 476 763 during the study period.

National Trends in Hospitalizations for Stroke Associated With Infective Endocarditis and Opioid Use Between 1993 and 2015

Background and Purpose- There has been a recent sharp rise in opioid-related deaths in the United States. Intravenous opioid use can lead to infective endocarditis (IE) which can result in stroke. There are scant data on recent trends in this neurological complication of opioid abuse. We hypothesized that increasing opioid abuse has led to a higher incidence of stroke associated with IE and opioid use. Methods- We used the 1993 to 2015 releases of the National Inpatient Sample and validated International Classification of Diseases, Ninth Revision, Clinical Modification codes ( ICD-9-CM) to identify hospitalizations with the combination of opioid abuse, IE, and stroke (defined as ischemic stroke, intracerebral hemorrhage, or subarachnoid hemorrhage). Survey weights provided by the National Inpatient Sample were used to calculate nationally representative estimates and population estimates from the United States. Census data were used to calculate annual hospitalization rates per 10 million person-years. Joinpoint regression was used to assess trends. Results- From 1993 through 2015, there were 5283 hospitalizations with stroke associated with IE and opioid use. Across this period, the rate of such hospitalizations increased from 2.4 (95% CI, 0.5-4.3) to 18.8 (95% CI, 14.4-23.3) per 10 million US residents. Joinpoint regression detected 2 segments: no significant change in the hospitalization rate was apparent from 1993 to 2008 (annual percentage change, 1.9%; 95% CI, -2.2% to 6.1%), and then rates significantly increased from 2008 to 2015 (annual percentage change, 20.3%; 95% CI, 10.5%-30.9%), most dramatically in non-Hispanic white patients in the Northeastern and Southern United States. Conclusions- US hospitalization rates for stroke associated with IE and opioid use were stable for ≈2 decades but then sharply increased starting in 2008, coinciding with the emergence of the opioid epidemic.

Clinical Characteristics and Factors Associated With Mortality in First-Episode Infective Endocarditis Among Persons Who Inject Drugs

IMPORTANCE

Persons who inject drugs (PWID) represent a distinct demographic of patients with infective endocarditis. Many centers do not perform valvular surgery on these patients owing to concerns about poor outcomes. Addiction services are underused in hospitals.

OBJECTIVES

To compare clinical characteristics in first-episode infective endocarditis in PWID who are surgically vs medically managed and to identify variables associated with mortality.

DESIGN, SETTING, AND PARTICIPANTS

This case series studied PWID treated for a first episode of infective endocarditis between April 1, 2007, and March 30, 2016. Participants were adult patients (aged ≥18 years) admitted to any of 3 hospitals in London, Ontario, Canada. Analysis occurred between July 2016 and November 2017.

MAIN OUTCOMES AND MEASURES

Survival among PWID; the causative organisms, site of infection, and cardiac as well as noncardiac complications; referral to addiction services; and surgical vs medical management.

RESULTS

Of 370 total first-episode cases of infective endocarditis, 202 (54.6%) were in PWID. Among PWID, 105 (52%) were male, the median (interquartile range) age was 34 (28-42) years, and patients were predominantly positive for the hepatitis C virus (69.8% [141 of 202]). Right-sided infection was more common (61.4% [124 of 202]), and most infections were caused by Staphylococcus aureus (77.2% [156 of 202]). Surgery occurred in 19.3% of patients (39 of 202). The all-cause mortality rate was 33.7% (68 of 202). Adjusting for age and sex, survival analysis demonstrated that surgery was associated with lower mortality (hazard ratio [HR], 0.44; 95% CI, 0.23-0.84; P = .01), as was referral to addiction treatment (HR, 0.29; 95% CI, 0.12-0.73; P = .008). Higher mortality was associated with left-sided infection (HR, 3.26; 95% CI, 1.82-5.84; P < .001) and bilateral involvement (HR, 4.51; 95% CI, 2.01-10.1; P < .001).

CONCLUSIONS AND RELEVANCE

This study presents the demographic characteristics of first-episode infective endocarditis in PWID. Results highlight the potentially important role of addictions treatment in this population. Further study to optimize selection criteria for surgery in PWID is warranted.

Occurrence of bacterial and toxic metals contamination in illegal opioid-like drugs in Iran: a significant health challenge in drug abusers

BACKGROUND

The toxic metals and/or bacterial contaminants in illicit drugs are the main health problems in drug users worldwide. Hence, the potential risks of these contaminants were evaluated in some of the illicit drugs during 2015 and 2016.

METHODS

The metals analysis were performed using graphite furnace atomic absorption spectrophotometry. In addition, all microbiological analysis stages, including handling procedures, dilution, and culture media, were conducted in accordance with the US Pharmacopeia (USP) which are harmonized with the European Pharmacopoeia (EP).

RESULTS

In the present study, the highest lead (Pb; 138.10 ± 75.01 μg/g) and chromium (Cr; 447.38 ± 20.27 μg/g) levels were detected in opium samples. In addition, the highest prevalence of microbial contamination was observed in opium samples, and the lowest was recorded in heroin samples. Clostridium tetani, with about 50% of contaminant, was the most common bacteria in the analyzed samples.

CONCLUSIONS

Our results indicate that Pb exposure as well as bacterial contamination could be the major threats for drug users. Graphical Abstract ᅟ.

Association between route of illicit drug administration and hospitalizations for infective endocarditis

Objective

This study examined the association between the route of drug administration and being hospitalized for infective endocarditis among 4817 treatment-seeking illicit drug users in Finland.

Methods

Cox regression models were used to examine the association between the route of drug administration and infective endocarditis hospitalization, adjusted for age, gender, and homelessness. Cases of infective endocarditis as a primary/main diagnosis were tracked using the 10th version of the International Classification of Disease code I33.

Results

In all, 47 persons had a primary diagnosis of infective endocarditis. These 47 persons contributed a total of 95 hospitalizations and their total length of hospital stay was 1393 days. There was a statistically significant difference in hospitalizations between injectors and non-injectors (Log-Rank test p = 0.018). Univariate Cox model showed that injectors had higher hazard or risk for infective endocarditis hospitalization compared to non-injectors (hazard ratio: 2.04, 95% confidence interval: 1.12-3.73, p = 0.020). After adjusting for age, gender, and homelessness in the multivariate model, the elevated hazard among injectors compared to non-injectors remained statistically significant with adjusted hazard ratio of 2.12 (95% confidence interval: 1.11-4.07, p = 0.024).

Conclusion

The study findings suggested a need to boost harm reduction measures targeting high-risk injecting and other health behaviors among injecting drug users in order to reduce their hospitalizations for infective endocarditis.

A retrospective epidemiologic study to define risk factors, microbiology, and clinical outcomes of infective endocarditis in a large tertiary-care teaching hospital

Objective:

This study aims to define risk factors as well as their association with microbiology and clinical outcomes in a large US infective endocarditis population.

Methods:

Hospital records were searched for appropriate infective endocarditis–related ICD codes from 16 July 2007 to 13 August 2015. A total of 363 cases were retrospectively identified that met definite Modified Duke Criteria for infective endocarditis and were analyzed by age group, causative organism, and associated risk factors for use of valvular surgical intervention, 30/90/180-day mortality after admission, and embolic phenomena.

Results:

Chronic hemodialysis was the most common risk factor (26.7% of cases). Of all age groups, those aged 78+ years had the lowest 30-day mortality but those aged 58–77 years had the highest mortality (p = 0.039). Staphylococcus aureus was the most prevalent causative organism. Those aged 78–97 years were more likely to have enterococcal infective endocarditis than those aged 18–27 years (p = 0.0144). Chronic hemodialysis associated infective endocarditis was more likely to be caused by coagulase-negative staphylococcus (p = 0.0121) and have a higher 30-day mortality (p = 0.141) than intravenous drug use associated infective endocarditis. Intravenous drug use and chronic hemodialysis were similarly likely to be caused by S. aureus. Intravenous drug use associated infective endocarditis was more likely to be caused by viridans group streptococci (p = 0.0001). Fungal infective endocarditis was most likely to embolize. Chronic hemodialysis patients were less likely to undergo valvular surgery (p = 0.001) and those with chronic hemodialysis who did had lower mortality than those only managed medically that did not reach statistical significance (p = 0.2991). Infective endocarditis caused by coagulase-negative staphylococci had the greatest 30-day mortality at 31.3% but did not reach statistical significance over all other causative organisms (p = 0.060).

Conclusion:

In our infective endocarditis population, S. aureus is the predominant causative organism. Chronic hemodialysis is the most common risk factor present in infective endocarditis populations and has greater association with coagulase-negative staphylococci and 30-day mortality. Intravenous drug use had the lowest mortality among risk factors with a similar proportion of S. aureus infective endocarditis compared to chronic hemodialysis but a higher proportion of viridans group streptococci infective endocarditis cases. Further study will need to be performed on prevention and treatment of infective endocarditis in chronic hemodialysis patients.

Candida-Bacteria Interactions: Their Impact on Human Disease

Candida species are the most common infectious fungal species in humans; out of the approximately 150 known species, Candida albicans is the leading pathogenic species, largely affecting immunocompromised individuals. Apart from its role as the primary etiology for various types of candidiasis, C. albicans is known to contribute to polymicrobial infections. Polymicrobial interactions, particularly between C. albicans and bacterial species, have gained recent interest in which polymicrobial biofilm virulence mechanisms have been studied including adhesion, invasion, quorum sensing, and development of antimicrobial resistance. These trans-kingdom interactions, either synergistic or antagonistic, may help modulate the virulence and pathogenicity of both Candida and bacteria while uniquely impacting the pathogen-host immune response. As antibiotic and antifungal resistance increases, there is a great need to explore the intermicrobial cross-talk with a focus on the treatment of Candida-associated polymicrobial infections. This article explores the current literature on the interactions between Candida and clinically important bacteria and evaluates these interactions in the context of pathogenesis, diagnosis, and disease management.

Acute ST Segment Elevation Myocardial Infarction and Massive Pericardial Effusion Due to Infective Endocarditis

Chest pain is a common complaint evaluated in the emergency department. While chest pain in a 22-year-old patient is typically a complaint of low acuity, high-acuity cases that rival those of the older patient population are well documented. We describe a case of complicated infective endocarditis in which point-of-care ultrasound (POCUS) aided the diagnosis of ST-elevation myocardial infarction secondary to a septic thrombus in a 22-year-old female with a history of intravenous drug use. Emergency physicians should be aware of the rare high-acuity cases as well as the impact of POCUS on rapid clinical assessment and treatment of patients of all ages presenting with chest pain.

The Changing Epidemiology of Infective Endocarditis in the Twenty-First Century

PURPOSE OF THE REVIEW

Infective endocarditis (IE) is a relatively infrequent infectious disease. It does, however, causes serious morbidity, and its mortality rate has remained unchanged at approximately 25%. Changes in IE risk factors have deeply impacted its epidemiology during recent decades but literature from low-income countries is very scarce. Moreover, prophylaxis guidelines have recently changed and the impact on IE incidence is still unknown.

RECENT FINDINGS

In high-income countries, the proportion of IE related to prior rheumatic disease has decreased significantly and has been replaced proportionally by cases related to degenerative valvulopathies, prosthetic valves, and cardiovascular implantable electronic devices. Nosocomial and non-nosocomial-acquired cases have risen, as has the proportion caused by staphylococci, and the median age of patients. In low-income countries, in contrast, rheumatic disease remains the main risk factor, and streptococci the most frequent causative agents. Studies performed to evaluate impact of guidelines changes' have shown contradictory results. The increased complexity of cases in high-income countries has led to the creation of IE teams, involving several specialties. New imaging and microbiological techniques may increase sensitivity for diagnosis and detection of IE cases. In low-income countries, IE remained related to classic risk factors. The consequences of prophylaxis guidelines changes are still undetermined.

Patients with Infectious Endocarditis and Drug Dependence Have Worse Clinical Outcomes after Valvular Surgery

BACKGROUND

Patients with infective endocarditis (IE) are at high risk for post-operative morbidity and death, which might be associated with drug abuse. The purpose of this study is to evaluate the impact of drug dependence on outcomes in patients who have IE and undergo valvular surgery (VS).

PATIENTS AND METHODS

The Nationwide/National Inpatient Sample 2001-2012 was queried to select patients with IE who had elective VS using International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis and procedure codes. Among them, patients with drug dependence (PDD) were identified, and their health status and post-operative outcomes were compared with those in patients without drug dependence (control group). Chi-square and Wilcoxon rank sum tests as well as multi-variable regression analysis were used for statistics.

RESULTS

A total of 809 (12.9%) PDD of the 6,264 patients who underwent VS were evaluated. They were younger compared with those in the control group (39.0 ± 10.8 y vs. 54.4 ± 14.8 y; p < 0.0001), had less age-related co-morbidities such as hypertension, diabetes mellitus, congestive heart failure, renal failure, obesity, but greater rates of alcohol abuse, liver disease, and psychoses. Despite the younger age and fewer co-morbidities, PDD compared with control patients were more likely to have post-operative complications develop overall (odds ratio [OR] = 1.6; 95% confidence interval [CI] 1.34-2.01), including infectious complications (OR = 1.5; 95% CI 1.27-1.78), specifically pneumonia (OR = 1.4; 95% CI 1.14-1.74) and sepsis (OR = 1.4; 95% CI 1.16-1.63), renal complications (OR = 1.5; 95% CI 1.23-1.77), and pulmonary embolism (OR = 1.9; 95% CI 1.44-2.52). Further, PDD had 11% longer hospital length of stay than those in the control groups (p < 0.0001). We did not find significant difference in hospital deaths, however, between these groups.

CONCLUSION

Drug dependence is associated with worse post-operative outcomes in patients with infective endocarditis who underwent valvular surgery and lengthens their hospital stay.

cUMP hydrolysis by PDE3A

As previously reported, the cardiac phosphodiesterase PDE3A hydrolyzes cUMP. Moreover, cUMP-degrading activity was detected in cow and dog hearts several decades ago. Our aim was to characterize the enzyme kinetic parameters of PDE3A-mediated cUMP hydrolysis and to investigate whether cUMP and cUMP-hydrolyzing PDEs are present in cardiomyocytes. PDE3A-mediated cUMP hydrolysis was characterized in time course, inhibitor, and Michaelis-Menten kinetics experiments. Intracellular cyclic nucleotide (cNMP) concentrations and the mRNAs of cUMP-degrading PDEs were quantitated in neonatal rat cardiomyocytes (NRCMs) and murine HL-1 cardiomyogenic cells. Moreover, we investigated cUMP degradation in HL-1 cell homogenates and intact cells. Educts (cNMPs) and products (NMPs) of the PDE reactions were detected by HPLC-coupled tandem mass spectrometry. PDE3A degraded cUMP (measurement of UMP formation) with a K _M value of ~143 μM and a V _max value of ~42 μmol/min/mg. PDE3A hydrolyzed cAMP with a K _M value of ~0.7 μM and a V _max of ~1.2 μmol/min/mg (determination of AMP formation). The PDE3 inhibitor milrinone inhibited cUMP hydrolysis (determination of UMP formation) by PDE3A (K _i = 57 nM). Significant amounts of cUMP as well as of PDE3A mRNA (in addition to PDE3B and PDE9A transcripts) were detected in HL-1 cells and NRCMs. Although HL-1 cell homogenates contain a milrinone-sensitive cUMP-hydrolyzing activity, intact HL-1 cells may use additional PDE3-independent mechanisms for cUMP disposal. PDE3A is a low-affinity and high-velocity PDE for cUMP. Future studies should investigate biological effects of cUMP in cardiomyocytes and the role of PDE3A in detoxifying high intracellular cUMP concentrations under pathophysiological conditions.

Opioid Dependent Malingerer with Self-Induced Sepsis

A 21-year-old woman was admitted to the emergency department (ED) with severe sepsis. Both the mechanism of infection and organisms discovered were unusual.

Medical complications of psychoactive substances with abuse risks: Detection and assessment by the network of French addictovigilance centres

The use of psychoactive substances, whether occasional or regular, can induce a large number of clinical and/or biological complications. These complications may be related to the effects of the active substance itself and/or adulterants, but also to the modalities for use (administrations route, contexts of use). The detection and evaluation of these potentially severe complications are a public health issue. Beyond the assessment of the potential for abuse of and dependence on psychoactive substances, the collection and evaluation of complications related to the use of the substances are one of the roles of addictovigilance centres. In this article, the expertise of the French addictovigilance centres in the detection and assessment of medical complications related to psychoactive substances, adulterants or route of administration of substances is advanced through a few recent examples.

Staphylococcus aureus Protein A Mediates Interspecies Interactions at the Cell Surface of Pseudomonas aeruginosa

While considerable research has focused on the properties of individual bacteria, relatively little is known about how microbial interspecies interactions alter bacterial behaviors and pathogenesis. Staphylococcus aureus frequently coinfects with other pathogens in a range of different infectious diseases. For example, coinfection by S. aureus with Pseudomonas aeruginosa occurs commonly in people with cystic fibrosis and is associated with higher lung disease morbidity and mortality. S. aureus secretes numerous exoproducts that are known to interact with host tissues, influencing inflammatory responses. The abundantly secreted S. aureus staphylococcal protein A (SpA) binds a range of human glycoproteins, immunoglobulins, and other molecules, with diverse effects on the host, including inhibition of phagocytosis of S. aureus cells. However, the potential effects of SpA and other S. aureus exoproducts on coinfecting bacteria have not been explored. Here, we show that S. aureus-secreted products, including SpA, significantly alter two behaviors associated with persistent infection. We found that SpA inhibited biofilm formation by specific P. aeruginosa clinical isolates, and it also inhibited phagocytosis by neutrophils of all isolates tested. Our results indicate that these effects were mediated by binding to at least two P. aeruginosa cell surface structures—type IV pili and the exopolysaccharide Psl—that confer attachment to surfaces and to other bacterial cells. Thus, we found that the role of a well-studied S. aureus exoproduct, SpA, extends well beyond interactions with the host immune system. Secreted SpA alters multiple persistence-associated behaviors of another common microbial community member, likely influencing cocolonization and coinfection with other microbes.

Bacteria rarely exist in isolation, whether on human tissues or in the environment, and they frequently coinfect with other microbes. However, relatively little is known about how microbial interspecies interactions alter bacterial behaviors and pathogenesis. We identified a novel interaction between two bacterial species that frequently infect together—Staphylococcus aureus and Pseudomonas aeruginosa. We show that the S. aureus-secreted protein staphylococcal protein A (SpA), which is well-known for interacting with host targets, also binds to specific P. aeruginosa cell surface molecules and alters two persistence-associated P. aeruginosa behaviors: biofilm formation and uptake by host immune cells. Because S. aureus frequently precedes P. aeruginosa in chronic infections, these findings reveal how microbial community interactions can impact persistence and host interactions during coinfections.

The causative agents in infective endocarditis: a systematic review comprising 33,214 cases

Infective endocarditis (IE) incidence remains high with considerable fatality rates; guidelines for prophylaxis against IE are currently under review in some settings which highlights the importance of maintaining up-to-date epidemiological estimates about the most common microbial causes. The objective of this systematic review, following PRISMA guidelines, was to identify the most common microbial causes of IE in recent years. Medline was searched from January 1, 2003 to March 31, 2013 for all articles containing the term "infective endocarditis". All relevant studies reporting diagnostic results were included. Special patient subpopulations were assessed separately. A total of 105 studies were included, from 36 countries, with available data on a total of 33,214 cases. Staphylococcus aureus was found to be the most common microorganism, being the most frequent in 54.3 % of studies (N = 57) (and in 55.4 % of studies using Duke's criteria for diagnosis [N = 51]). Viridans group streptococci (VGS), coagulase-negative staphylococci (CoNS), Enterococcus spp and Streptococcus bovis were among the most common causes. S. aureus was the most common pathogen in almost all population subgroups; however, this was not the case in patients with implantable devices, prosthetic valves, or immunocompromised non-HIV, as well as in the sub-group from Asia, emphasizing that a global one-size-fits-all approach to the management of suspected IE is not appropriate. This review provides an evidence-based map of the most common causative agents of IE, highlighting S. aureus as the leading cause in the 21st century. The changing epidemiology of IE in some patient sub-groups in the last decade and the very high number of microbiologically undiagnosed cases (26.6 %) suggest the need to revisit IE prophylaxis and diagnostic strategies.

Intravenous melatonin abuse leading to recurrent aortic valve endocarditis: a case report and discussion

BACKGROUND

Reports of inappropriate medication use are widespread. There is a growing literature detailing abuse of drugs not typically thought to have high abuse liability. Melatonin is considered to be generally safe and is categorized by the Food and Drug Administration as a nutritional supplement. There are no known reports of intravenous melatonin abuse in the medical literature.

CASE PRESENTATION

The authors report a case of a patient injecting melatonin with euphoric and then sedative effects leading to two episodes of infective endocarditis culminating in aortic valve replacement.

CONCLUSION

Infective endocarditis continues to be a major potential complication of intravenous drug abuse. The proliferation of novel street drugs, resurgence in the use of older drugs and ongoing abuse of medications warrant continued research and vigilance in treating substance use disorders and attendant medical complications.

Cardiac surgery for infective endocarditis in patients with intravenous drug use

OBJECTIVES

Intravenous drug users have a high risk of infective endocarditis and reduced survival. Cardiac surgery may be recommended for these patients, but redo surgery is controversial. This study describes the characteristics and outcomes of intravenous drug users accepted for surgery during a 12-year period.

METHODS

This retrospective study included 29 injecting drug users treated with valve surgery for endocarditis between January 2001 and December 2013 at a tertiary academic centre. Survival was assessed by Kaplan-Meier analysis.

RESULTS

The median patient age was 36 (24-63) years and 27 patients (93%) were male. Staphylococcus aureus (52%) and Enterococcus faecalis (17%) were the most common microorganisms. Common illicit drugs were opioids (69%), amphetamines (52%) and benzodiazepines (24%). Mixed abuse was reported in 66% of patients. Seven patients (24%) had prior intracardial implants or native valve pathology. Twenty-five patients (86%) were positive for hepatitis C virus antibody, but none carried the human immunodeficiency virus. Twelve (41%) were homeless and 15 (52%) had poor dental hygiene. Three patients (10%) received medication-assisted rehabilitation before surgery. The main indications for surgery were regurgitation and secondary heart failure (86%), embolization (41%) and uncontrolled infection (24%). Aortic valve replacement was performed in 24 patients (83%), either as part of univalvular or multiple valve surgery. Seven patients (24%) had multivalvular endocarditis. All but 3 patients received biological valve prostheses. The 30-day mortality was 7% after first time surgery. During follow-up, 15 patients (52%) presented with reinfection: 10 (35%) were offered a second and 2 (7%) a third operation. Thirty-day mortality was 10% after redo surgery. Thirteen patients (45%) died within a median of 22 (0-84) months. Continued intravenous drug use was reported in 70 and 44% of patients after the first and second operation, respectively.

CONCLUSIONS

Cardiac surgery for infective endocarditis has acceptable early postoperative results among intravenous drug users. The 2- and 5-year survival were 79 and 59%, respectively. The number of reinfections was high within 2 years, as continued drug use seems to be a major challenge for this group.

Injection of Pharmaceuticals Designed for Oral Use: Harms Experienced and Effective Harm Reduction Through Filtration

Several pharmaceutical products are liable to 'abuse' or use outside their prescription, which frequently involves their injection. Examples are slow-release forms of morphine and oxycodone, and sublingual buprenorphine. During injection preparation, the drug is extracted into water, after crushing and heating the tablet if considered necessary. Since these products are designed for oral administration, they can contain excipients (ingredients other than the drug) which are poorly soluble, resulting in suspension of particles in the injection solution. Injected particles are able to produce medical complications such as the blockage of small blood vessels leading to ischaemia (inadequate blood flow) and tissue damage. Filtration can be used to remove particles from the suspension; including bacteria if the porosity is small enough (0.2 μm). However, filters are liable to blockage when overloaded, especially if the pore size is small. This problem can be minimised by using a larger pore size (e.g. 5-10 μm), but the resulting filtrate will contain many residual small particles. The use of two filters, coarse and fine, either sequentially or in a double membrane device, enables removal of the majority of particles as well as bacteria, although not quite meeting pharmaceutical standards for safe injection. Although not yet evaluated by a clinical trial, this highly effective filtration process would be expected to greatly reduce the risk of vascular and related complications, as well as non-viral infections. Careful technique ensures that drug is not lost by filtration, a priority for most drug consumers. Practical issues that affect acceptability of filtration by injecting drug users, including ease of use and cost, will need to be considered. However, given the laboratory evidence demonstrating the effectiveness of filters it is time to consider these tools as essential for safe injection as sterile needles/syringes for the world's approximately 16 million people who inject drugs.

Polymicrobial infective endocarditis caused by Neisseria sicca and Haemophilus parainfluenzae

Infective endocarditis is a common clinical problem in industrialized countries. Risk factors include abnormal cardiac valves, a history of endocarditis, intracardiac devices, prosthetic valves and intravenous drug use. We report a case of polymicrobial infective endocarditis in a 33 year-old female with a history chronic heroin use caused by Neisseria sicca and Haemophilus parainfluenzae. We believe the patient was exposed to these microbes by cleansing her skin with saliva prior to injection. Pairing a detailed history with the consideration of atypical agents is crucial in the proper diagnosis and management of endocarditis in patients with high-risk injection behaviors.

Infective endocarditis in an HIV-infected intravenous drug user

Infective endocarditis is a common complication among injecting drug users. Disease risk among these patients is increased by the spread of HIV infection. In the following article, we discuss the exceptional clinical presentation of a 28-year-old patient who used intravenous drugs (heroin) for 10 years, had been infected with HIV for seven years and as a complication had developed Staphylococcus aureus infective endocarditis. The patient came to the hospital in serious condition, complaining of bodily pain, swelling of the legs and general weakness. During hospitalization, besides infective endocarditis, she was also diagnosed with anemia, toxic hepatitis, renal failure, ascites, sepsis, and pneumonia. A completely disrupted tricuspid valve, damaged aortic valve, and fibrosis of the mitral valve were detected. Echocardiographic and radiologic data showed that the patient's condition continued to deteriorate day by day, with significant progression of heart failure, ejection fraction decreasing from 45% to 10%, and development of myocarditis, hydrothorax and pericarditis. However, this progressive worsening of the patient's condition ceased when vancomycin was administered. To the authors' knowledge, this is the first such case described in the literature in which significant improvement was observed despite the patient's complex condition with associated complications.

Surgical management of tricuspid valve endocarditis in the current era: A review

The incidence of isolated tricuspid valve infective endocarditis is increasing. Medical management is the mainstay of treatment but surgical intervention is required in a subset of patients. Surgical treatment options include valve excision and replacement or valve reconstruction. We searched PubMed and the Cochrane library to identify articles to be included in this review of surgical outcomes. References of selected articles were crosschecked for other relevant studies. Surgical management of tricuspid valve endocarditis can be achieved with satisfactory outcomes. However, the optimal indication and timing of surgery remain unclear, and the frequent association with intravenous drug use complicates management. Repair techniques are preferable though there is no clear evidence supporting one method over another.