Infective endocarditis in renal transplant recipients

Infective endocarditis and solid organ transplantation: Only worse outcomes during initial transplantation hospitalization

BACKGROUND

The epidemiology, and outcome of infective endocarditis (IE) among solid organ transplant (SOT) recipients is unknown.

METHODS

We used data from the 2013-2018 Nationwide Readmissions Database (NRD). IE- and SOT-associated hospitalizations were identified using diagnosis and procedure codes. Outcomes included inpatient mortality, length of stay, and inpatient costs. Adjusted analyses were performed using weighted regression models.

RESULTS

A total of 99,052 IE-associated hospitalizations, corresponding to a weighted national estimate of 193,164, were included for analysis. Of these, 794 (weighted n = 1,574) were associated with transplant history (SOT-IE). Mortality was not significantly different between SOT-IE and non-SOT-IE (17.2% vs. 15.8%, adjusted relative risk [aRR]: 0.86, 95% confidence interval [CI] [0.71, 1.03]), and fewer SOT-IE patients underwent valve repair or replacement than non-SOT-IE (12.5% vs. 16.2%, aRR 0.82, 95% CI [0.71, 0.95]). We then compared outcomes of patients diagnosed with IE during their index transplant hospitalization (index-SOT-IE) to patients without IE during their transplant hospitalization (index-SOT). Index-SOT-IE occurred most frequently among heart transplant recipients (45.1%), and was associated with greater mortality (27.1% vs. 2.3%, aRR 6.07, 95% CI [3.32, 11.11]).

CONCLUSION

Dual diagnosis of SOT and IE was associated with worse outcomes among SOT recipients during index hospitalization, but not overall among patients with IE.

High Mortality and Graft Loss after Infective Endocarditis in Kidney Transplant Recipients: A Case-Controlled Study from Two Centers

Kidney transplant recipients (KTRs) tend to develop infections with characteristic epidemiology, presentation, and outcome. While infective endocarditis (IE) is among such complications in KTRs, the literature is scarce. We describe the presentation, epidemiology, and factors associated with IE in KTRs. We performed a retrospective case/control study which included patients from two centers. First episodes of definite or possible IE (Duke criteria) in adult KTRs from January 2010 to December 2018 were included, as well as two controls per case, and followed until 31 December 2019. Clinical, biological, and microbiological data and the outcome were collected. Survival was studied using the Kaplan-Meier method. Finally, we searched for factors associated with the onset of IE in KTRs by the comparison of cases and controls. Seventeen cases and 34 controls were included. IE was diagnosed after a mean delay of 78 months after KT, mostly on native valves of the left heart only. Pathogens of digestive origin were most frequently involved (six Enterococcus spp, three Streptococcus gallolyticus, and one Escherichia coli), followed by Staphylococci (three cases of S. aureus and S. epidermidis each). Among the risk factors evaluated, age, vascular nephropathy, and elevated calcineurin inhibitor through levels were significantly associated with the occurrence of IE in our study. Patient and death-censored graft survival were greatly diminished five years after IE, compared to controls being 50.3% vs. 80.6% (p < 0.003) and 29.7% vs. 87.5% (p < 0.002), respectively. IE in KTRs is a disease that carries significant risks both for the survival of the patient and the transplant.

Brucellosis in transplant recipients: A systematic review

BACKGROUND

Brucellosis is a bacterial disease caused by Brucella species. The purpose of this study was to evaluate brucellosis in all types of transplant patients.

METHODS

All the cases of brucellosis in transplant patients with no time and language limitations were searched and retrieved on May 20, 2020, using the following search keywords: (Brucella OR Brucellosis) AND (Transplant OR Transplantation) through the following medical databases: Web of Sciences, Google Scholar, Scopus, PubMed, and regional databases, for example, SID. All clinical features, including the time of transmission (before, during, and after transplantation), treatment protocols and medications, and patients' outcomes were investigated.

RESULTS

A total of 14 cases reported in 14 studies (out of 777 studies) were retrieved. Kidney (50%), liver (28.5%), and hematopoietic stem cell transplantation (14.2%) were the most reported types of transplantation. The presentation of brucellosis in 42.8% of the patients occurred in the early post-transplantation period, whereas 57.1% of the cases presented with late onset disease.

CONCLUSION

Brucellosis in transplant recipients seems to be uncommon even in the endemic regions. However, rare cases could be transmitted through bone marrow transplantation and transfusion. Precise screening and meticulous supervision during and after transplantation might lead to a reduction in the frequency of brucellosis.

Endocarditis in kidney transplant recipients: a systematic review

Infective Endocarditis (IE) carries significant mortality. Bacteremia, which is a predisposing factor for IE, occurs more frequently in immunocompromised individuals. Interestingly, IE in kidney transplant recipients has not been adequately described. The aim of this study was to systematically review all published cases of IE in kidney transplant recipients and describe their epidemiology, microbiology, clinical characteristics, treatment and outcomes. A systematic review of PubMed (through 13^th December 2019) for studies providing epidemiological, clinical, microbiological as well as treatment data and outcomes of IE in kidney transplant recipients was performed. A total of 60 studies, containing data of 117 patients, were included in the analysis. The most common causative pathogens were gram-positive microorganisms in 57.4%, gram-negative microorganisms in 14.8%, fungi in 20%, while in 18.9% of cases, IE was culture-negative. Aortic valve was the most commonly infected valve followed by mitral, tricuspid and the pulmonary valve. Diagnosis was set with a transthoracic ultrasound in half the cases, followed by transesophageal ultrasound and autopsy. Fever was present in most cases, while embolic phenomena were noted in two out of five cases. Aminoglycosides, cephalosporins and aminopenicillins were the most commonly used antimicrobials, and surgical management was performed in one out of three cases. Clinical cure was noted in 60.9%, while overall mortality was 45.3%. To conclude, this systematic review thoroughly describes IE in kidney transplant recipients and provides information on epidemiology, clinical presentation, treatment and outcomes. Moreover, it identifies the emerging role of Enterococci, gram-negatives and fungi in IE in this population.

First Case of Brucella Pneumonia in a Lung Transplant Patient: Case Report and Review of the Literature

Brucella is one of the most common zoonotic diseases worldwide. It is endemic in the Mediterranean basin. Brucella pneumonia is a rare complication of brucellosis that can present with a variety of clinical and radiological manifestations. It was described only once previously in the setting of solid organ transplant.

A 32-year-old female from Saudi Arabia with cystic fibrosis and bronchiectasis presented five weeks after a bilateral lung transplant with fever and cough. Investigation showed high inflammatory markers in addition to a pulmonary infiltrate in the chest imaging. All microbiological workups were negative including bronchoalveolar lavage cultures. Brucella serology was positive and she was started on anti-Brucella therapy which resulted in complete resolution of her symptoms and radiological changes. This case demonstrates an unusual presentation of Brucellosis. It highlights the importance of epidemiology in evaluating post-transplant infections. We reviewed and summarized the literature on brucellosis post solid organ transplant and the various treatment regimens for Brucella pneumonia.

This is the first case report of Brucella pneumonia in a lung transplant patient. Brucella is a rare complication post solid organ transplant but it has a good prognosis.

Brucellosis in renal transplant recipients: a comparative review of 5 cases

Although brucellosis in renal transplant recipients is rare, we studied the clinical characteristics of this infection in this patient population due to the significantly increased number of renal transplantations performed over the past few decades. We report one case from our experience and undertake a review of the previously reported cases retrieved from the PubMed. A total of 5 cases of brucellosis in renal transplant recipients were found to date. The mean time from transplantation to diagnosis of brucellosis was 4.7 years (range, 4 months to 13 years). Blood culture and detection of anti-Brucella antibodies were frequently used diagnostic investigations. Treatment with appropriate antibiotic regimen led to a clinical cure and marked improvement in Brucella titre in all the patients. This review illustrates that clinicians should remain vigilant for this infectious aetiology following renal transplantation. Further studies are required to delineate the magnitude and scope of this association.

Travel vaccination recommendations and endemic infection risks in solid organ transplantation recipients

BACKGROUND

Solid organ transplant (SOT) recipients are often heavily immunosuppressed and consequently at risk of serious illness from vaccine preventable viral and bacterial infections or with endemic fungal and parasitic infections. We review the literature to provide guidance regarding the timing and appropriateness of vaccination and pathogen avoidance related to the immunological status of SOT recipients.

METHODS

A PUBMED search ([Vaccination OR vaccine] AND/OR ["specific vaccine"] AND/OR [immunology OR immune response OR cytokine OR T lymphocyte] AND transplant was performed. A review of the literature was performed in order to develop recommendations on vaccination for SOT recipients travelling to high-risk destinations.

RESULTS

Whilst immunological failure of vaccination in SOT is primarily the result of impaired B-cell responses, the role of T-cells in vaccine failure and success remains unknown. Vaccination should be initiated at least 4 weeks prior to SOT or more than 6 months post-SOT. Avoidance of live vaccination is generally recommended, although some live vaccines may be considered in the specific situations (e.g. yellow fever). The practicing physician requires a detailed understanding of region-specific endemic pathogen risks.

CONCLUSIONS

We provide a vaccination and endemic pathogen guide for physicians and travel clinics involved in the care of SOT recipients. In addition, recommendations based on timing of anticipated immunological recovery and available evidence regarding vaccine immunogenicity in SOT recipients are provided to help guide pre-travel consultations.

Pulmonary Involvement in Brucellosis, a Rare Complication of Renal Transplant: Case Report and Brief Review

Brucellosis, a disease endemic in many countries including Turkey, is a systemic infectious disease. Brucellosis is rare in renal transplant recipients. Only 4 cases have been reported in the literature. In this report, we describe the clinical manifestations and laboratory findings of a brucellosis case with pulmonary involvement in a renal transplant recipient. A 20-year-old man who had a living-donor kidney transplant 4 months earlier presented to our transplant clinic with fever, cough, and right flank pain. Clarithromycin and ceftriaxone were started for the diagnosis of pneumonia. However, piperacillin/tazobactam, meropenem plus teicoplanin, and antituberculosis treatment were continued because the patient was unresponsive to the initial therapy. Serum Brucella agglutination titer was found to be 1/320. Treatment was started with a 6-week course of oral doxycycline and rifampin, resulting in cure. Brucellosis and especially its pulmonary involvement are rare after kidney transplant. However, in endemic areas,it should be considered as it mimics several other infectious diseases.

Infective endocarditis after renal transplantation

Background:

Infective endocarditis (IE) is a serious complication in immunosuppressive patients that has adverse effects.

Objectives:

The aim of this study was to define the characteristics, outcomes, and correlating factors of mortality in renal transplant recipients.

Patients and Methods:

Infective endocarditis was diagnosed in 22 patients from three renal transplant centers in Iran between 2000 and 2010. Modified Duke criteria were applied to confirm the diagnosis.

Results:

Twenty-two renal transplant patients with IE were evaluated. Blood culture results were positive in 81%. Enteroccous and group D non-enterococcal were the causative microorganisms in 31% and 25% of patients, respectively. In-hospital and 12-month mortality was 41% and the mortality rate was higher in older patients in comparison to younger patients. Overall, the rates of one-year disease-free patient and graft survival were 49% and 88%, respectively.

Conclusions:

Despite the availability of different and potent antibiotics, the mortality caused by IE remains considerably high. These patients are significantly prone to endovascular infections that affect the mortality and survival.

Brucellosis in a renal transplant recipient

Brucellosis is one of the most common systemic zoonotic diseases transmitted by consumption of unpasteurized dairy products or by occupational contact with infected animals. Brucellosis is rare in renal transplant recipients. Only 3 cases have been reported in the literature. We report a case of brucellosis with hematologic and hepatobiliary complications in a patient 3 years after renal transplantation. The mean time from transplantation to the diagnosis of brucellosis in these 4 reported patients was 5.1 years (range 17 months to 13 years). All patients had fever and constitutional symptoms, and all attained clinical cure after combination antibiotic therapy. Given the small number of patients, further study is needed to identify the characteristics of brucellosis in renal transplant recipients. Drug interactions and acute renal failure developed in our patient during antibiotic treatment. Therefore, we should monitor the levels of immunosuppressive agents frequently. Several studies have shown in vitro susceptibilities of Brucella melitensis to tigecycline. In our patient, fever finally subsided after tigecycline administration. The minimum inhibitory concentration of tigecycline using Etest was 0.094 μg/mL. Tigecycline may be a potential option for treatment of brucellosis in the setting of transplantation.

Molecular diagnosis of microbial aetiologies using SepsiTest™ in the daily routine of a diagnostic laboratory

A universal PCR and sequencing test, SepsiTest™ (Molzym, Germany) was evaluated for its applicability during daily diagnostic routine in a privately operated laboratory. In total, 96 specimens originating from 66 patients under suspect of infectious endocarditis, infections of joints, encephalitis/meningitis, systemic infections and infections of unknown genesis were PCR analysed and compared to culture results. Samples comprised cultured and non-cultured blood, synovial fluid, synovial tissue, heart valves, pacemakers, spinal tissue, cerebrospinal fluid, and swabs. PCR and culture were concordant in 26 negative and 8 positive cases (51.5%). A group of 25 patients was culture-negative but PCR-positive (37.9%). In at least 14 of these, common and/or rare aetiologies were identified, while for 4 patients the results of 16S PCR could not be unequivocally linked with the underlying disease. Benefits and limitations of the molecular test are discussed with special emphasis on technical and economic issues. In conclusion, SepsiTest™ proved to be a valuable tool for the diagnosis of aetiologies, particularly in cases of culture-negative patients who are under strong suspicion for an infection.

Brucella infection with pancytopenia after pediatric liver transplantation

Brucellosis is considered the most widespread zoonosis in the world. It has been reported that the prevalence of seropositivity among the Turkish population varies from 3% to 14%. We present a case of brucellosis after pediatric liver transplantation. A 15-year-old boy with the diagnosis of neuro Wilson's disease underwent deceased-donor liver transplantation. The postoperative immunosuppressive protocol consisted of steroids and tacrolimus. Two months after the operation the patient experienced fever to 40°C. The patient complained of poor appetite, headache, and diarrhea. He had had pancytopenia. Despite administration of appropriate antibiotics, antiviral and antifungal agents, fever persisted for > 1 month. Multiple blood, urine, stool, and sputum cultures were negative. Bone marrow aspirate revealed hypocellularity. Liver biopsy was performed, but rejection was not observed on biopsy specimen. Brucella serology was positive and Brucella agglutination titer was 1:320. Bone marrow culture was positive for Brucella but blood culture was negative. The patient was then treated with oral doxycycline and rifampin for 8 weeks. No previous case report about Brucella infection after liver transplantation has appeared in the literature, to our knowledge; our case is presented as the first. Bone marrow hypoplasia is a rare feature of Brucella infection. Our patient with brucellosis and pancytopenia had had hypocellular bone marrow. The clinical and hematologic findings resolved with treatment of the infection. Brucella infection should be suspected in liver transplanted recipients with fever of unknown origin, especially in a recipient who has lived in an endemic area. Brucella also should be considered as a possible diagnosis in patients with pancytopenia.

Nocardia cyriacigeorgica: a case of endocarditis with disseminated soft-tissue infection

Nocardia cyriacigeorgica is a common environmental organism. It has been isolated from clinical samples in Europe, Asia and North America, predominantly from respiratory samples but also from samples from several other sites. We present a case report of an 85-year-old female patient in the UK who was found to have a multi-focal soft-tissue infection from which N. cyriacigeorgica was isolated. She had a background history of chronic obstructive pulmonary disease and corticosteroid use for polymyalgia rheumatica. During the course of her treatment echocardiography showed the presence of a mobile heart mass attached to a valve leaflet, a major Dukes criterion for endocarditis. We suggest that in cases of disseminated Nocardia infection, endocarditis should be tested for, particularly in cases failing to respond to treatment. We also review previous reports of both N. cyriacigeorgica infection, and of endocarditis due to Nocardia species and related genera.

Successful treatment of Staphylococcus aureus bacterial endocarditis in a renal transplant recipient

We report the successful treatment of Staphylococcus aureus endocarditis in a renal transplant recipient with preservation of his renal allograft. A 44-year-old man presented to the emergency room with sudden onset of fevers and rigors 7 weeks after renal transplantation. Infective endocarditis was diagnosed by Duke's Criteria (Durack et al. New criteria for the diagnosis of infective endocarditis. Am J Med 1994: 96: 200-209) with multiple positive blood cultures for S. aureus and a mitral valve vegetation on transesophageal echocardiogram. He was treated with intravenous antibiotics for 6 weeks with continuation of his immunosuppression. He has remained clinically stable for over 5 years. Although the treatment of S. aureus endocarditis in immunosuppressed transplant patients has traditionally resulted in loss of their allograft, prompt diagnosis and appropriate antibiotics with continued immunosuppressive therapy resulted in a successful outcome and allograft preservation in this case.

Outcomes of renal transplant and waiting list patients with bacterial endocarditis in the United States

BACKGROUND

Bacterial endocarditis is associated with poor long-term survival among dialysis patients. Renal transplant patients and those waiting list for renal transplantation are predisposed to developing bacterial endocarditis; data regarding incidence and outcomes are limited.

METHODS

Patients hospitalised for bacterial endocarditis were identified from patients transplanted or waiting list between 1995 and 2003. Transplant and waiting list cohorts were derived from the United States Renal Data System (USRDS) database. All patients had Medicare as primary payer. Long-term survival was estimated by the Kaplan-Meier method. Cox proportional hazards analysis was used to identify independent predictors of bacterial endocarditis.

RESULTS

During the study period, 282 renal transplant patients and 549 waiting list patients were hospitalised with bacterial endocarditis. Incidence rates of bacterial endocarditis per 1000 patient-years were 5.6 among waiting list patients, 2.6 among deceased-donor transplant recipients and 1.8 among living-donor transplant recipients. In-hospital mortality rates were 16.0% for the renal transplant cohort and 18.6% for the waiting list cohort. Two-year post-endocarditis survival rates were 58% for transplant patients and 41% for waiting list patients. The most powerful predictors of bacterial endocarditis among transplant patients were donor age, patient age, diabetic end-stage renal disease (ESRD) and prior dialysis time longer than 2 years.

CONCLUSIONS

Renal transplant patients hospitalised with bacterial endocarditis sustain high in-hospital and long-term mortality rates. Waiting list patients are at higher risk of developing bacterial endocarditis than renal transplant recipients.

Zoonoses in Solid-Organ and Hematopoietic Stem Cell Transplant Recipients

Numerous reports exist of the transmission of zoonoses to humans during and after solid-organ and hematopoietic stem cell transplantation. Donor-derived infections of numerous etiologies, including West Nile virus infection, Chagas disease, toxoplasmosis, rabies, lymphocytic choriomeningitis virus infection, and infection due to Brucella species have been reported. Most zoonoses occur as a primary infection after transplantation, and immunocompromised patients are more likely to experience significant morbidity and mortality from these infections. Risks of zoonotic infection in the posttransplantation period could be reduced by patient education. Increased recognition of the risks of zoonoses, as well as the advent of molecular biology-based testing, will potentially augment diagnostic aptitude. Documented zoonotic infection as it affects transplantation will be the primary focus of this review.

Vancomycin-resistant enterococci: colonization, infection, detection, and treatment

Vancomycin-resistant enterococci (VRE) are becoming a major concern in medical practice. Their increased prevalence and their ability to transfer vancomycin resistance to other bacteria (including methicillin-resistant Staphylococcus aureus) have made them a subject of close scrutiny and intense investigation. Colonization is usually acquired by susceptible hosts in an environment with a high rate of patient colonization with VRE (eg, intensive care units, oncology units). Vancomycin-resistant enterococci can survive in the environment for prolonged periods (>1 week), can contaminate almost any surface, and can be passed from one patient to another by health care workers. Whether VRE colonization leads to infection depends on the health status of the patient. Whereas immunocompetent patients colonized with VRE are at low risk for infection, weakened hosts (patients with hematologic disorders, transplant recipients, or severely ill patients) have an increased likelihood of developing infection following colonization. Quinupristin-dalfopristin and linezolid are among the anti-infective agents that have recently become available to treat infection caused by VRE. Other antimicrobials are currently under development. Molecular techniques such as polymerase chain reaction and standard culture studies are being used to detect VRE colonization, infection, and outbreaks.

Nosocomial infective endocarditis in critically ill patients: a report of three cases and review of the literature

Nosocomial infective endocarditis (NIE) is a relatively uncommon but nevertheless a serious complication affecting critically ill hospitalized patients who are frequently exposed to life-saving invasive procedures. We report three cases of NIE in a tertiary-care hospital encountered during a period of two years. The first case developed in a 50% burn-injured patient; the second in a liver transplant recipient; and the third in a renal transplant recipient. All patients met indications for cardiac surgical intervention, however, the patient who had received a liver transplant (case 2) was considered a poor candidate and unfit for surgery; she subsequently died. The other two patients underwent open-heart surgery. The burns patient (case 1) survived; conversely, the renal transplant recipient (case 3) died postoperatively. We have reviewed the literature concerning NIE in critically ill patients and describe the epidemiology, microbiology and clinical features of this uncommon infection and comment on its diagnosis and management.

Infective Endocarditis in Patients with Kidney Failure: Chronic Dialysis and Kidney Transplant

Physicians who treat patients with infective endocarditis (IE) are encountering a growing number of dialysis and kidney transplant patients. Both groups have 30 to 100 times higher risk of IE, with 1-year mortalities of 40% to 60%. The predominant organisms causing IE are gram positive, with 60% to 80% of cases due to Staphylococcus aureus, and another 10% to 20% of cases due to coagulase-negative staphylococci. Renal transplant patients may develop fungal IE, but this risk is primarily in the first 3 months after transplant. In addition to blood cultures, transesophageal echocardiogram is the most useful diagnostic examination for IE in these patients. Initial antibiotic therapy, pending final culture and antibiotic susceptibility results, should provide coverage against the most common organisms and allow for the potential of either methicillin or vancomycin-resistant species. Removal of infected hemodialysis access devices and at least 4 to 6 weeks of intravenous antibiotics are recommended. Antibiotic prophylaxis against IE has been recommended for all dialysis and renal transplant patients, but this strategy is controversial and unproven.

Vascular and cardiac infections in end-stage renal disease

Patients with end-stage renal disease (ESRD) receiving hemodialysis (HD) are vulnerable to intravascular and endocardial infections. These include vascular access infections, vascular stent infections, and bacterial endocarditis. Staphylococcus aureus is the most commonly encountered microorganism in these conditions. Prolonged intravenous antibiotic therapy is often indicated in these infections. Surgical removal of the infected vascular access or stent may be required. Infective endocarditis occurs less frequently in renal transplant recipients than in patients on HD. Although bacterial endocarditis may occur, fungal endocarditis with organisms such as Aspergillus and Candida species occurs with disproportionately high frequency among renal transplant recipients because of immunosuppression. Prolonged intravenous antibiotic or antifungal therapy is indicated, and valve replacement is often necessary.