Arboviruses Recommendations for Solid-Organ Transplant Recipients and Donors

South Asian Transplant Infectious Disease Guidelines for Solid Organ Transplant Candidates, Recipients, and Donors

These guidelines discuss the epidemiology, screening, diagnosis, posttransplant prophylaxis, monitoring, and management of endemic infections in solid organ transplant (SOT) candidates, recipients, and donors in South Asia. The guidelines also provide recommendations for SOT recipients traveling to this region. These guidelines are based on literature review and expert opinion by transplant physicians, surgeons, and infectious diseases specialists, mostly from South Asian countries (India, Pakistan, Bangladesh, Nepal, and Sri Lanka) as well as transplant experts from other countries. These guidelines cover relevant endemic bacterial infections (tuberculosis, leptospirosis, melioidosis, typhoid, scrub typhus), viral infections (hepatitis A, B, C, D, and E; rabies; and the arboviruses including dengue, chikungunya, Zika, Japanese encephalitis), endemic fungal infections (mucormycosis, histoplasmosis, talaromycosis, sporotrichosis), and endemic parasitic infections (malaria, leishmaniasis, toxoplasmosis, cryptosporidiosis, strongyloidiasis, and filariasis) as well as travelers' diarrhea and vaccination for SOT candidates and recipients including travelers visiting this region. These guidelines are intended to be an overview of each topic; more detailed reviews are being published as a special supplement in the Indian Journal of Transplantation .

Virucidal antiviral activity of Maytenus quadrangulata extract against Mayaro virus: Evidence for the presence of catechins

ETHNOPHARMACOLOGICAL RELEVANCE

Mayaro virus (MAYV) is an arbovirus endemic to the Amazon region, which comprises the states of the North and Midwest region of Brazil and encompasses the largest tropical forest in the world, the Amazon Forest. The confirmation of its potential transmission by Aedes aegypti and recent cases in Brazil, mainly in large centers in the northern region, led to the classification of Mayaro fever as an emerging disease. Traditional medicine is commonly used to treat various diseases, mainly by local riverside populations. Some species of the genus Maytenus, which have similar morphologies, are popularly used to treat infections and inflammations. In this context, our research group has studied and confirmed the antiviral activity of several plant-derived compounds. However, several species of this same genus have not been studied and therefore deserve attention.

AIM OF THE STUDY

This study aimed to demonstrate the effects of ethyl acetate extracts of leaves (LAE) and branches (TAE) of Maytenus quadrangulata against MAYV.

MATERIALS AND METHODS

Mammalian cells (Vero cells) were used to evaluate the cytotoxicity of the extracts. After cell infection by MAYV and the treatment with the extracts, we evaluated the selectivity index (SI), the virucidal effect, viral adsorption and internalization, and the effect on viral gene expression. The antiviral action was confirmed by quantifying the viral genome using RT-qPCR and by analyzing the effect on virus yield in infected cells. The treatment was performed based on the effective concentration protective for 50% of the infected cells (EC₅₀).

RESULTS

The leaves (LAE; EC₅₀ 12.0 μg/mL) and branches (TAE; EC₅₀ 101.0 μg/mL) extracts showed significative selectivity against the virus, with SI values of 79.21 and 9.91, respectively, which were considered safe. Phytochemical analysis revealed that the antiviral action was associated with the presence of catechins, mainly in LAE. This extract was chosen for the subsequent studies since it reduced the viral cytopathic effect and virus production, even at high viral loads [MOI (multiplicity of infection) 1 and 5]. The effects of LAE resulted in a marked reduction in viral gene expression. The viral title was drastically reduced when LAE was added to the virus before infection or during replication stages, reducing virus production up to 5-log units compared to infected and untreated cells.

CONCLUSION

Through kinetic replication, MAYV was not detected in Vero cells treated with LAE throughout the viral cycle. The virucidal effect of LAE inactivates the viral particle and can intercept the virus at the end of the cycle when it gains the extracellular environment. Therefore, LAE is a promising source of antiviral agents.

Fatal Yellow Fever in a Kidney Transplant Patient

A kidney-transplanted patient, unvaccinated against yellow fever (YF), developed high fever, progressed rapidly to hepatic insufficiency and coma, and died 8 days later. Real-time polymarase chain reaction for YF virus collected on the seventh day of symptoms was positive. Autopsy showed disseminated infection and midzonal hepatitis with apoptotic hepatocytes and minimal inflammatory reaction.

Urban Spread of Flaviviruses: A New Challenge in Solid-organ Transplant Recipients

Yellow fever has never previously been reported in transplant recipients. The first reported case of yellow fever in a kidney transplant recipient in Brazil and the re-emergence of arboviruses in many areas of the world dictate the need of studies aimed to answer multiple unanswered questions.

Chikungunya in a kidney transplant recipient: a case report

In 2004, a global spread of Chikungunya fever affected most tropical and subtropical regions of the world. In 2016, an outbreak occurred in Northeast Brazil with hundreds of cases documented. Solid organ transplant recipients have a modified immune response to infection and the clinical course is usually different from immunocompetent patients. The diagnosis can be challenging in this population. Most reports describe patients residing in endemic areas, although we must emphasize the importance of differential diagnosis in kidney transplanted travelers who visit endemic regions, such as Northeast Brazil. Here, we reported a case of a kidney transplant recipient that acquired Chikungunya fever after a trip to an endemic region at Northeast Brazil during the outbreak in 2016, with a good clinical evolution. We also present warning recommendations for travelers to endemic areas as additional measures to prevent disease outbreaks.

Donor-derived infections, lessons learnt from the past, and what is the future going to bring us

PURPOSE OF REVIEW

Donor-derived transmission of infectious diseases is a well-recognized complication of solid organ transplantation (SOT). Most donor-derived disease transmissions are expected. Although uncommon, unexpected donor-derived infections can be associated with significant morbidity and mortality, and as the volume of patients undergoing SOT increases, the number of infections transmitted through organ donation can also be expected to rise. The growing gap between the number of patients waiting for transplantation and available organs continue in fact to be the number one issue facing the transplant community. As a consequence the major focus in organ transplantation has been developing strategies to increase the available organs, including the use of organs from donors with infections or risky behaviors that have disqualified them from the donation in the past.

RECENT FINDINGS

In addition to the commonly reported donor-derived transmissions, an increasing number of studies have reported unusual infections transmitted by SOT.

SUMMARY

Transplant surgeons and physicians should increase their awareness toward uncommon donor-derived infections including them in the differential diagnosis of unusual clinical pictures in their recipients.

Donor-derived infections: Guidelines from the American Society of Transplantation Infectious Diseases Community of Practice

These updated guidelines from the Infectious Diseases Community of Practice of the American Society of Transplantation will review the current state of the art of donor-derived infections. Specifically, the guideline will summarize standardized definitions and approaches to defining imputability, updated data on the epidemiology of donor-derived infections, and approaches to risk mitigation against transmission of infections. This update will additionally provide guidance on the use of HIV+ donors in HIV+ recipients, the use of HCV-viremic donors in non-viremic recipients, donors with endemic infections, and donors with bacteremia, meningitis, and encephalitis. Lastly, the guidance will summarize an approach to recipients with a suspected donor-derived infection.

Strategies for safe living following solid organ transplantation-Guidelines from the American Society of Transplantation Infectious Diseases Community of Practice

The present AST-IDCOP guidelines update information on strategies for safe living after organ transplantation. While transplantation carries an increased risk for infection from the recipient's environment due to lifelong immunosuppression, the goal is for the recipient to be able to return to their home and live as normal a life as possible with a functioning graft. The current guideline provides updates to prior recommendations including additions on infections from water and food sources, exposures to animals, cannabis use as well as sexual exposures or those encountered with travel. Similar to the prior editions, many of the recommendations are based on good infection prevention standards, extrapolation from other immunocompromised hosts, and risks found from cases series in transplant patients. Enhanced education and attention to incorporating safe living strategies into daily life should help to accomplish successful transplant with recipients achieving a fulfilling life away from the hospital.

Emergent Arboviruses and Renal Transplantation: A Global Challenge

In recent years, Zika, Chikungunya, Dengue, West Nile Fever, and Yellow Fever epidemics have generated some concerns. Besides difficulties related to vector control, there are challenges related to behavior of pathologies not yet fully understood. The transplanted population requires additional care due to immunosuppressive drugs. Furthermore, the potential risk of transmission during donation is another source of uncertainty and generates debate among nephrologists in transplant centers. Do the clinical outcomes and prognoses of these infections tend to be more aggressive in this population? Is there a risk of viral transmission via kidney donation? In this review article, we address these issues and discuss the relationship between arbovirus and renal transplantation.

Recommendations for Management of Endemic Diseases and Travel Medicine in Solid-Organ Transplant Recipients and Donors: Latin America

The Recommendations for Management of Endemic Diseases and Travel Medicine in Solid-Organ Transplant Recipients and Donors: Latin America clinical practice guideline is intended to guide clinicians caring for solid-organ transplant (SOT) donors, candidates and recipients regarding infectious diseases (ID) issues related to this geographical region, mostly located in the tropics. These recommendations are based on both systematic reviews of relevant literature and expert opinion from both transplant ID and travel medicine specialists. The guidelines provide recommendations for risk evaluation and laboratory investigation, as well as management and prevention of infection of the most relevant endemic diseases of Latin America. This summary includes a brief description of the guideline recommendations but does not include the complete rationale and references for each recommendation, which is available in the online version of the article, published in this journal as a supplement. The supplement contains 10 reviews referring to endemic or travel diseases (eg, tuberculosis, Chagas disease [ChD], leishmaniasis, malaria, strongyloidiasis and schistosomiasis, travelers diarrhea, arboviruses, endemic fungal infections, viral hepatitis, and vaccines) and an illustrative section with maps (http://www.pmourao.com/map/). Contributors included experts from 13 countries (Brazil, Canada, Chile, Denmark, France, Italy, Peru, Spain, Switzerland, Turkey, United Kingdom, United States, and Uruguay) representing four continents (Asia, the Americas and Europe), along with scientific and medical societies.