Single donor-derived strongyloidiasis in three solid organ transplant recipients: case series and review of the literature

Donor-Derived Infection's Prevention and Control in Kidney Transplantation

BACKGROUND

The study aimed to summarize the experience of donor selection and recipient therapy in the face of potential donor-derived infections and improve the quality of donor organ utilization, which would help reduce the risk of infection after recipient operation and decrease the risk of loss or even death of recipient kidney transplantation.

METHODS

In this study, 132 kidneys from 70 donors and their recipients who underwent surgery between July 2017 and January 2021 were studied to perform a retrospective analysis of their etiologic examination results and treatment process.

RESULTS

In the 70 donors, only 25 had negative etiologic examination results, accounting for 35.71%. Among the 132 recipients, 31.82% had positive culture results, 3 (2.27%) experienced donor-derived infections, and one died.

CONCLUSIONS

Although infection in the donor before the donation is quite common, the incidence of donor-derived infections is relatively low. The targeted and preventive application of adequate sensitive antibiotics in the whole course of therapy was the cornerstone for treating recipients at potential risk of potential donor-derived infection. The changes in infection indicators in the recipient should be closely monitored, which would guide medication adjustments timely. These measures could, to a great degree, ensure the prognosis of the recipient, in turn reducing the adverse events caused by donor-derived infections.

Donor heart selection: Evidence-based guidelines for providers

The proposed donor heart selection guidelines provide evidence-based and expert-consensus recommendations for the selection of donor hearts following brain death. These recommendations were compiled by an international panel of experts based on an extensive literature review.

Strongyloides hyper-infection in a lung transplant recipient: Case report and review of the literature

CASE PRESENTATION

A 63-year-old man with a left single lung transplant for end-stage combined restrictive and obstructive lung disease developed persistent pulmonary infiltrates and recurrent gram-negative bacteremia post-transplant. Bronchoalveolar lavage fluid revealed a nematode on Papanicolau staining compatible with Strongyloides stercoralis larvae on day 50 post-transplant. Although Strongyloides serology performed post-transplant was negative, a retrospective review of the medical record revealed marked peripheral blood eosinophilia on several occasions before transplantation. Despite reduction in immunosuppression and treatment with albendazole and ivermectin, the patient developed another episode of Escherichia coli bacteremia. He died 3 months post-transplant from pulmonary and neurological complications.

DIAGNOSIS

Strongyloides hyper-infection.

DISCUSSION

Strongyloides hyper-infection syndrome is known to occur in immunocompromised patients, but it has only been reported once in a lung transplant recipient. This case illustrates the importance of screening for parasitic infections before transplantation in patients with marked eosinophilia, especially among immigrants from countries in which Strongyloides is endemic. Hyper-infection syndrome may appear years after infection in the context of immunosuppression or immunodeficiency. This case also highlights the association between Strongyloides hyper-infection and bacteremia with enteric organisms.

Testing deceased organ donors for infections: An organ procurement organization survey

Organ procurement organizations (OPO) test potential deceased organ donors for infectious diseases required by policy, but many also perform testing for additional infections. The current state of donor testing in the United States is unknown. We sent an IRB approved survey to all 57 U.S. OPOs using REDCap. Descriptive statistics were performed. From the 57 OPOs, we received 46 (80.7%) unique responses with all 11 United Network of Organ Sharing regions represented. Forty of 46 (87%) OPO respondents consulted an Infectious Diseases physician when needed. Eighteen of 46 (39%) tested for West Nile virus (WNV) and 17 of 18 (94%) tested year-round. Eleven of 46 (23.9%) tested for Strongyloides infection while 17 of 46 (37%) tested for Chagas disease. All OPOs performed prospective nucleic acid testing (NAT) for HIV, hepatitis B and hepatitis C on all donors. OPO testing of additional infections has increased since prior surveys but remains variable. Standardization of organ donor infectious diseases evaluation should be considered.

Nosocomial Infections: Do Not Forget the Parasites!

Nosocomial infections (NIs) pose an increasing threat to public health. The majority of NIs are bacterial, fungal, and viral infections; however, parasites also play a considerable role in NIs, particularly in our increasingly complex healthcare environment with a growing proportion of immunocompromised patients. Moreover, parasitic infections acquired via blood transfusion or organ transplantation are more likely to have severe or fatal disease outcomes compared with the normal route of infection. Many of these infections are preventable and most are treatable, but as the awareness for parasitic NIs is low, diagnosis and treatment are often delayed, resulting not only in higher health care costs but, importantly, also in prolonged courses of disease for the patients. For this article, we searched online databases and printed literature to give an overview of the causative agents of parasitic NIs, including the possible routes of infection and the diseases caused. Our review covers a broad spectrum of cases, ranging from widely known parasitic NIs, like blood transfusion malaria or water-borne cryptosporidiosis, to less well-known NIs, such as the transmission of Strongyloides stercoralis by solid organ transplantation or nosocomial myiasis. In addition, emerging NIs, such as babesiosis by blood transfusion or person-to-person transmitted scabies, are described.

Review of the impact of donor characteristics on pediatric heart transplant outcomes

Heart transplantation (HTx) is a treatment option for end-stage heart failure in children. HTx is limited by the availability and acceptability of donor hearts. Refusal of donor hearts has been reported to be common with reasons for refusal including preexisting donor characteristics. This review will focus on the impact of donor characteristics and comorbidities on outcomes following pediatric HTx. A literature review was performed to identify articles on donor characteristics and comorbidities and pediatric HTx outcomes. There are many donor characteristics to consider when accepting a donor heart. Weight-based matching is the most common form of matching in pediatric HTx with a donor-recipient weight ratio between 0.7 and 3 having limited impact on outcomes. From an age perspective, donors <50 years can be carefully considered, but the impact of ischemic time needs to be understood. To increase the donor pool, with minimal impact on outcomes, ABO-incompatible donors should be considered in patients that are eligible. Other factors to be considered when accepting an organ is donor comorbidities. Little is known about donor comorbidities in pediatric HTx, with most of the data available focusing on infections. Being aware of the potential infections in the donor, understanding the testing available and risks of transmission, and treatment options for the recipient is essential. There are a number of donor characteristics that potentially impact outcomes following pediatric HTx, but these need to be taken into consideration along with their interactions with recipient factors when interpreting the outcomes following HTx.

Transplant-related strongyloidiasis in solid organ transplant recipients in Saudi Arabia and the Gulf Cooperation Council countries

BACKGROUND

Strongyloidiasis is a devastating disease with a mortality rate exceeding 50% in immunocompromised patients. The disease usually results from reactivation of a latent infection in a transplant patient. Alternatively, donor-derived transmission of Strongyloides may occur.

METHODS

In this review, we report a case of Strongyloides hyperinfection syndrome in a liver transplant recipient to illustrate the severity of this infection. Following this, PubMed was searched for cases of transplant-related strongyloidiasis in the Gulf Cooperation Council (GCC) countries. Demographic data, the clinical presentation of recipients, and donor information were recorded. Methods of diagnosis, treatment planning, and clinical outcomes were documented.

RESULTS

A total of 12 transplant-related strongyloidiasis cases were identified. Seventy-five percent of the patients were from Saudi Arabia. Three cases from Kuwait shared common donors. All donors were deceased and native to an area endemic for Strongyloides. Five of the patients shared common donors, raising the possibility of donor-derived infection. Neither the donors nor the recipients underwent screening tests for Strongyloides. Concomitant bacteremia and/or meningitis was seen in 50% of cases (6/12). Moreover, when documented, sepsis was detected in all of the patients who died (three cases). The mortality rate in this series was high (41.7%).

CONCLUSIONS

Since this is a preventable condition, early diagnosis and treatment is essential. The screening and treatment of potential transplant recipients and donors proved to be an effective preventive measure. There is a growing need for further studies and implementation of screening policies in the GCC countries to prevent this fatal infection.

Strongyloidiasis hyperinfection after renal transplant presenting as diffuse alveolar hemorrhage with respiratory failure

Strongyloides stercoralis is a helminthic enteric parasite estimated to infect at least 30 to 100 million people globally. It is transmitted via contaminated soil with a unique ability to complete its entire life cycle in the human host. It is common in humid, tropical, and subtropical regions of the world and is endemic in the Southeastern United States. Strongyloidiasis hyperinfection has been described in a variety of conditions that impair host immunity, including immunosuppression after transplantation. The syndrome has a high mortality rate but may initially present with nonspecific symptoms. A high degree of clinical suspicion coupled with early detection and aggressive therapeutic measures is paramount to a successful outcome.

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.

Pneumonia in solid organ transplantation: Guidelines from the American Society of Transplantation Infectious Diseases Community of Practice

These guidelines from the AST Infectious Diseases Community of Practice review the diagnosis and management of pneumonia in the post-transplant period. Clinical presentations and differential diagnosis for pneumonia in the solid organ transplant recipient are reviewed. A two-tier approach is proposed based on the net state of immunosuppression and the severity of presentation. With a lower risk of opportunistic, hospital-acquired, or exposure-specific pathogens and a non-severe presentation, empirical therapy may be initiated under close clinical observation. In all other patients, or those not responding to the initial therapy, a more aggressive diagnostic approach including sampling of tissue for microbiological and pathological testing is warranted. Given the broad range of potential pathogens, a microbiological diagnosis is often key for optimal care. Given the limited literature comparatively evaluating diagnostic approaches to pneumonia in the solid organ transplant recipient, much of the proposed diagnostic algorithm reflects clinical experience rather than evidence-based data. It should serve as a template which may be modified according to local needs. The same holds true for the suggested empiric therapies, which need to be adapted to the local resistance patterns. Further study is needed to comparatively evaluate diagnostic and empiric treatment strategies in SOT recipients.

Donor-derived strongyloidiasis in a Saudi pediatric kidney transplant recipient: A case report and mini-review

S. stercoralis infection has been identified as a donor-derived infection in cases of solid organ transplant among recipients with no prior risk factor for parasitic exposure. Worldwide and regional reports from the adult kidney transplant population highlight this indirect method of infection and caution about delayed diagnosis, severe complications, and death related to donor-derived S. stercoralis infection. We report a deceased-donor-derived S. stercoralis infection in a 12-year-old Saudi girl who underwent kidney transplantation. This is the first pediatric case reported outside the United States of America. Although she presented with mild bouts of gastrointestinal symptoms, the need for additional immune suppression put her at risk of serious complications. A literature review highlights the importance of awareness about S. stercoralis infections and complications in kidney transplant recipients, pretransplant screening of donors based on risk assessment, and the challenges with treatment availability and duration in this vulnerable population.

Infectious Disease Transmission in Solid Organ Transplantation: Donor Evaluation, Recipient Risk, and Outcomes of Transmission

In 2016, the Transplantation Society of Australia and New Zealand, with the support of the Australian Government Organ and Tissue authority, commissioned a literature review on the topic of infectious disease transmission from deceased donors to recipients of solid organ transplants. The purpose of this review was to synthesize evidence on transmission risks, diagnostic test characteristics, and recipient management to inform best-practice clinical guidelines. The final review, presented as a special supplement in Transplantation Direct, collates case reports of transmission events and other peer-reviewed literature, and summarizes current (as of June 2017) international guidelines on donor screening and recipient management. Of particular interest at the time of writing was how to maximize utilization of donors at increased risk for transmission of human immunodeficiency virus, hepatitis C virus, and hepatitis B virus, given the recent developments, including the availability of direct-acting antivirals for hepatitis C virus and improvements in donor screening technologies. The review also covers emerging risks associated with recent epidemics (eg, Zika virus) and the risk of transmission of nonendemic pathogens related to donor travel history or country of origin. Lastly, the implications for recipient consent of expanded utilization of donors at increased risk of blood-borne viral disease transmission are considered.

Is This Organ Donor Safe?: Donor-Derived Infections in Solid Organ Transplantation

Infection is an inevitable complication of solid organ transplantation. Unrecognized infection may be transmitted from a donor and result in disseminated disease in the immunosuppressed host. Recent outbreaks of deceased donor-derived infections resulting in high rates of mortality and severe morbidity have emphasized the need to be cautious in using donors with possible meningoencephalitis. Screening of organ donors for potential transmissible infections is paramount to improving transplantation outcomes.

Is This Organ Donor Safe?: Donor-Derived Infections in Solid Organ Transplantation

Infection is an inevitable complication of solid organ transplantation. Unrecognized infection may be transmitted from a donor and result in disseminated disease in the immunosuppressed host. Recent outbreaks of deceased donor-derived infections resulting in high rates of mortality and severe morbidity have emphasized the need to be cautious in using donors with possible meningoencephalitis. Screening of organ donors for potential transmissible infections is paramount to improving transplantation outcomes.

Eosinophilia and Kidney Disease: More than Just an Incidental Finding?

Peripheral blood eosinophilia (PBE), defined as 500 eosinophils or above per microliter (µL) blood, is a condition that is not uncommon but often neglected in the management of patients with chronic kidney disease (CKD), acute kidney injury (AKI), or patients on renal replacement therapy (RRT). The nature of PBE in the context of kidney diseases is predominantly secondary or reactive and has to be distinguished from primary eosinophilic disorders. Nonetheless, the finding of persistent PBE can be a useful clue for the differential diagnosis of underdiagnosed entities and overlapping syndromes, such as eosinophilic granulomatosis with polyangiitis (EGPA), IgG4-related disease (IgG4-RD), acute interstitial nephritis (AIN), or the hypereosinophilic syndrome (HES). For patients on RRT, PBE may be an indicator for bio-incompatibility of the dialysis material, acute allograft rejection, or Strongyloides hyperinfection. In a subset of patients with EGPA, eosinophils might even be the driving force in disease pathogenesis. This improved understanding is already being used to facilitate novel therapeutic options. Mepolizumab has been licensed for the management of EGPA and is applied with the aim to abrogate the underlying immunologic process by blocking interleukin-5. The current article provides an overview of different renal pathologies that are associated with PBE. Further scientific effort is required to understand the exact role and function of eosinophils in these disorders which may pave the way to improved interdisciplinary management of such patients.

High seroprevalence of Strongyloides stercoralis among individuals from endemic areas considered for solid organ transplant donation: A retrospective serum-bank based study

Background

Strongyloides stercoralis is a worldwide disseminated parasitic disease that can be transmitted from solid organ transplant (SOT) donors to recipients. We determined the serological prevalence of S. stercoralis among deceased individuals from endemic areas considered for SOT donation, using our institution’s serum bank.

Methodology

Retrospective study including all deceased potential donors from endemic areas of strongyloidiasis considered for SOT between January 2004 and December 2014 in a tertiary care hospital. The commercial serological test IVD-Elisa was used to determine the serological prevalence of S. stercoralis.

Principal findings

Among 1025 deceased individuals during the study period, 90 were from endemic areas of strongyloidiasis. There were available serum samples for 65 patients and 6 of them tested positive for S. stercoralis (9.23%). Only one of the deceased candidates was finally a donor, without transmitting the infection.

Conclusions

Among deceased individuals from endemic areas considered for SOT donation, seroprevalence of strongyloidiasis was high. This highlights the importance of adhering to current recommendations on screening for S. stercoralis among potential SOT donors at high risk of the infection, together with the need of developing a rapid diagnostic test to fully implement these screening strategies.

Strongyloidiasis is a neglected tropical disease caused by a parasite which is endemic in most parts of the world. It can cause a life-threatening disease among immunosuppressed individuals and can be transmitted from solid organ transplant donors to recipients. We retrospectively investigated the prevalence of strongyloidiasis among deceased individuals from endemic areas who were considered for solid organ transplant donation in our center, by performing a serological assay using our institution’s serum bank. We found a high prevalence of strongyloidiasis among these deceased candidates to donation, but only one of the six who tested positive was finally a donor, without transmitting the disease to recipients. Our results should encourage physicians to adhere to current guidelines which recommend active screening of strongyloidiasis in potential solid organ transplant donors from endemic areas who may be infected. There is a clear need for a rapid diagnostic test to fully implement systematic screening among these individuals.

Solid Organ Transplant and Parasitic Diseases: A Review of the Clinical Cases in the Last Two Decades

The aim of this study was to evaluate the occurrence of parasitic infections in solid organ transplant (SOT) recipients. We conducted a systematic review of literature records on post-transplant parasitic infections, published from 1996 to 2016 and available on PubMed database, focusing only on parasitic infections acquired after SOT. The methods and findings of the present review have been presented based on the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) checklist. From data published in the literature, the real burden of parasitic infections among SOT recipients cannot really be estimated. Nevertheless, publications on the matter are on the increase, probably due to more than one reason: (i) the increasing number of patients transplanted and then treated with immunosuppressive agents; (ii) the “population shift” resulting from immigration and travels to endemic areas, and (iii) the increased attention directed to diagnosis/notification/publication of cases. Considering parasitic infections as emerging and potentially serious in their evolution, additional strategies for the prevention, careful screening and follow-up, with a high level of awareness, identification, and pre-emptive therapy are needed in transplant recipients.

Successful Treatment of Strongyloides stercoralis Hyperinfection in a Kidney Transplant Recipient: Case Report

Strongyloides stercoralis (SS) can cause hyperinfection and disseminated infection in immunosuppressed individuals, with risk of mortality. We report the case of a cadaveric kidney transplant recipient who developed gastrointestinal symptoms and eosinophilia, approximately 3 months after transplantation. Stool examination and esophagogastroduodenoscopy with biopsies were positive for SS larvae. The patient was started on oral ivermectin and immunosuppression was reduced, but still the clinical picture got worse with metabolic ileus and respiratory symptoms, with the need for administration of subcutaneous ivermectin and combined therapy with albendazol. The patient survived and graft function was preserved. The patient was unlikely to be the source of infection. We also present a review of cases of SS infection in kidney transplant recipients.

Anemia, intractable vomiting, chronic diarrhea, and syndrome of inappropriate antidiuretic secretion: a diagnostic dilemma: Disseminated strongyloidosis in a patient with newly diagnosed HTLV infection-case report and review of literature

RATIONALE

Strongyloidiasis hyperinfection and disseminated disease have high mortality rates due to several complications and early detection of Strongyloides infection is therefore prudent.

PATIENT CONCERNS

A 37-year-old male patient came with chronic diarrhea, intractable vomiting and was found to have hyponatremia, and anemia on the initial laboratory tests.

DIAGNOSES

Further work up revealed syndrome of inappropriate antidiuretic secretion to be the cause of the hyponatremia in addition to gastrointestinal loses. His hospital course was complicated by persistent hyponatremia and later development of partial small bowel obstruction.

INTERVENTIONS

Considering his symptoms we had a suspicion of small bowel pathology for which he underwent an esophagogastroduodenoscopywith biopsies that revealed strongyloidosis as the cause of his symptoms. He was also found to have human T-cell lymphotropic virus infection, likely contributing to the disseminated disease.

OUTCOMES

He was started on ivermectin with complete resolution of symptoms and improvement of hyponatremia.

LESSONS

It is very important to suspect Strongyloides infection in a patient presenting with syndrome ofinappropriate antidiuretic secretion as hyperinfection and disseminated disease can be life threatening without antihelmintic therapy.

KDIGO Clinical Practice Guideline on the Evaluation and Care of Living Kidney Donors

The 2017 Kidney Disease: Improving Global Outcomes (KDIGO) Clinical Practice Guideline on the Evaluation and Care of Living Kidney Donors is intended to assist medical professionals who evaluate living kidney donor candidates and provide care before, during and after donation. The guideline development process followed the Grades of Recommendation Assessment, Development, and Evaluation (GRADE) approach and guideline recommendations are based on systematic reviews of relevant studies that included critical appraisal of the quality of the evidence and the strength of recommendations. However, many recommendations, for which there was no evidence or no systematic search for evidence was undertaken by the Evidence Review Team, were issued as ungraded expert opinion recommendations. The guideline work group concluded that a comprehensive approach to risk assessment should replace decisions based on assessments of single risk factors in isolation. Original data analyses were undertaken to produce a "proof-in-concept" risk-prediction model for kidney failure to support a framework for quantitative risk assessment in the donor candidate evaluation and defensible shared decision making. This framework is grounded in the simultaneous consideration of each candidate's profile of demographic and health characteristics. The processes and framework for the donor candidate evaluation are presented, along with recommendations for optimal care before, during, and after donation. Limitations of the evidence are discussed, especially regarding the lack of definitive prospective studies and clinical outcome trials. Suggestions for future research, including the need for continued refinement of long-term risk prediction and novel approaches to estimating donation-attributable risks, are also provided.In citing this document, the following format should be used: Kidney Disease: Improving Global Outcomes (KDIGO) Living Kidney Donor Work Group. KDIGO Clinical Practice Guideline on the Evaluation and Care of Living Kidney Donors. Transplantation. 2017;101(Suppl 8S):S1-S109.

Strongyloides stercoralis in solid organ transplantation: early diagnosis gets the worm

PURPOSE OF REVIEW

Strongyloidiasis is a parasitic infection affecting millions of people worldwide. Complications of infection are strongly associated with alcoholism, immunosuppression, and organ transplantation. Delayed diagnosis results in hyperinfection syndrome and disseminated strongyloidiasis leading to mortality rates approaching 80%. Early detection, and prevention of infection and transmission are key to diminish this illness.

RECENT FINDINGS

In this review, we cover the basic concepts in immunity, immunosuppression, and disorder necessary for understanding the infectious syndromes associated with Strongyloides stercoralis infection. Focused discussion on donor-derived transmission and recipient risk in solid organ transplantation is presented. Current methodology for diagnosis, screening algorithms, and treatment are also reviewed.

SUMMARY

Strongyloidiasis complicated by hyperinfection and dissemination remains associated with a poor outcome. The poor outcome pleads for a high level of suspicion and aggressive treatment in at-risk patients. As the population of transplant patients continues to increase, the risk of infection also increases, compelling us to address this highly fatal infectious complication in solid organ transplantation (SOT). Here we review the pathology, immunology, diagnosis, and treatment of strongyloides infection in the immunosuppressed SOT population.

Evidence-Based Guidelines for Screening and Management of Strongyloidiasis in Non-Endemic Countries

Strongyloidiasis is an intestinal parasitic infection becoming increasingly important outside endemic areas, not only because of the high prevalence found in migrant populations, but also because immunosuppressed patients may suffer a potentially fatal disseminated disease. The aim of these guidelines is to provide evidence-based guidance for screening and treatment of strongyloidiasis in non-endemic areas. A panel of experts focused on three main clinical questions (who should be screened and how, how to treat), and reviewed pertinent literature available in international databases of medical literature and in documents released by relevant organizations/societies. A consensus of the experts' opinion was sought when specific issues were not covered by evidence. In particular, six systematic reviews were retrieved and constituted the main support for this work. The evidence and consensus gathered led to recommendations addressing various aspects of the main questions. Grading of evidence and strength of recommendation were attributed to assess the quality of supporting evidence. The screening of individuals at risk of the infection should be performed before they develop any clinical complication. Moreover, in immunosuppressed patients, the screening should be mandatory. The screening is based on a simple and widely accessible technology and there is now a universally accepted treatment with a high efficacy rate. Therefore, the screening could be implemented as part of a screening program for migrants although further cost-effectiveness studies are required to better evaluate this strategy from a public health point of view.

Strongyloidiasis Current Status with Emphasis in Diagnosis and Drug Research

Strongyloidiasis is a parasitic neglected disease caused by the nematode Strongyloides stercoralis affecting 30 to 100 million people worldwide. Complications, strongly associated with alcoholism, organ transplants, and HTLV-1 virus, often arise due to late diagnosis, frequently leading to patient death. Lack of preemptive diagnosis is not the only difficulty when dealing with this parasite, since there are no gold standard diagnostic techniques, and the ones used have problems associated with sensitivity, resulting in false negatives. Treatment is also an issue as ivermectin and benzimidazoles administration leads to inconsistent cure rates and several side effects. Researching new anti-Strongyloides drugs is a difficult task since S. stercoralis does not develop until the adult stages in Mus musculus (with the exception of SCID mice), the main experimental host model. Fortunately, alternative parasite models can be used, namely, Strongyloides ratti and S. venezuelensis. However, even with these models, there are other complications in finding new drugs, which are associated with specific in vitro assay protocol steps, such as larvae decontamination. In this review, we highlight the challenges associated with new drug search, the compounds tested, and a list of published in vitro assay methodologies. We also point out advances being made in strongyloidiasis diagnosis so far.

Strongyloides hyperinfection following hematopoietic stem cell transplant in a patient with HTLV-1-associated T-cell leukemia

Strongyloides stercoralis has the potential to cause accelerated autoinfection in immunocompromised hosts. Screening tests for strongyloidiasis may be falsely negative in the setting of immunosuppression. We report a case of Strongyloides hyperinfection syndrome in a patient with human T-lymphotropic virus type 1-associated T-cell leukemia early after hematopoietic stem cell transplant. The diagnosis was made by stool ova and parasite examination, despite a negative screening enzyme-linked immunosorbent assay. Because of anticipated prolonged neutropenia, an extended course of treatment was utilized.

Screening of living organ donors for endemic infections: Understanding the challenges and benefits of enhanced screening

Living organ donor candidates are screened for medical and psychosocial contraindications to donation. One important goal of this process is to prevent donor-derived infectious diseases transmissions. These transmissions are exceptionally rare, but have the potential to cause significant morbidity and mortality. The Organ Procurement and Transplantation Network now requires each recovery hospital to develop a protocol for evaluating living donors for tuberculosis and other geographically-defined endemic pathogens, including Trypanosoma cruzi (the causative pathogen of Chagas' disease), Strongyloides stercoralis, and West Nile Virus (WNV), in addition to universal screening for blood-borne pathogens. Enhanced screening requirements were developed in response to the changing epidemiology and endemicity of these diseases, as well as recent case reports of donor-derived disease transmission. Living organ donor disease screening presents a number of unique challenges to clinicians and policy-makers, including deciding which donors to test, which testing modality to use, when to test, and appropriate interpretation of results. This review will analyze the epidemiology of T. cruzi, S. stercoralis, and WNV, the assays available for screening for these diseases, and the subsequent impact on the living organ donor process . This article is protected by copyright. All rights reserved.

Donor-Derived Strongyloidiasis Infection in Solid Organ Transplant Recipients: A Review and Pooled Analysis

BACKGROUND

Donor-derived Strongyloides stercoralis infection in solid organ transplant (SOT) recipients is uncommon. Immunosuppressed SOT recipients are at risk of developing severe forms of strongyloidiasis infection through transmission from an infected donor allograft.

METHODS

PubMed was searched for English-written articles published up to April 2015. Articles that reported cases of donor-derived strongyloidiasis infection in SOT recipients were reviewed for a pooled analysis.

RESULTS

A total of 27 cases were identified from various SOT recipients. Donors were mostly from Strongyloides endemic regions (23 cases). No transplant recipients received prophylaxis against strongyloidiasis infection. Median age was 53 years. Median time of presenting symptoms after the solid organ transplantation was 72 days. The most common presenting symptoms were gastrointestinal (GI) symptoms (19 cases; 70.4%). Diagnosis of strongyloidiasis infection was mainly made by the confirmation of Strongyloides larvae or worm in GI samples (19 cases) and respiratory samples (14 cases). Donor-derived strongyloidiasis infection was evidenced by serology test results in 17 cases and epidemiological risk assessment analysis in 10 cases. Ivermectin was the most commonly used medication with use of a combination of iverrmectin and albendazole or thiabendazole in 15 cases. Death was noted in 9 cases (34.6%) of 26 cases with known outcomes. Presence of sepsis or bacteremia was a predictor of mortality because it was seen in 9 patients who died (100.0%) and in 4 patients who survived (23.5%; P < .001).

CONCLUSIONS

Donor-derived strongyloidiasis infection in SOT recipients has high mortality. Effective donor screening and prophylaxis in high-risk SOT recipients may help to decrease morbidity and mortality associated with donor-derived strongyloidiasis.

Donor-derived Strongyloides stercoralis hyperinfection syndrome after simultaneous kidney/pancreas transplantation

Most cases of strongyloidiasis associated with solid organ transplantation have been due to the reactivation of a latent infection in the recipient as a result of the immunosuppressive therapy; however, donor-derived infections are becoming increasingly frequent. The case of a patient who nearly died of a Strongyloides stercoralis hyperinfection after receiving simultaneous kidney/pancreas transplants is described herein. No specific parasitological tests were performed pre-transplantation, despite the fact that both the recipient and the donor originated from endemic areas. Serological analysis of the donor's serum performed retrospectively revealed the origin of the infection, which if it had been done beforehand would have prevented the serious complications. Current practice guidelines need to be updated to incorporate immunological and molecular techniques for the rapid screening of Strongyloides prior to transplantation, and empirical treatment with ivermectin should be applied systematically when there is the slightest risk of infection in the donor or recipient.

Real-Time Polymerase Chain Reaction in Stool Detects Transmission of Strongyloides stercoralis from an Infected Donor to Solid Organ Transplant Recipients

Solid organ transplant recipients can acquire Strongyloides stercoralis from an infected donor. The diagnosis of S. stercoralis in immunocompromised individuals may be challenging due to a lower sensitivity of available parasitological and serological methods, compared with immunocompetent individuals. Recently, a real-time polymerase chain reaction (RT-PCR) in stool has been developed for S. stercoralis diagnosis. We report two cases of S. stercoralis infection transmitted by a donor to two solid organ transplant recipients, who were diagnosed with RT-PCR in stool. This test could play an important role inS. stercoralis diagnosis in immunosuppressed patients, facilitating rapid treatment initiation and reducing the risk of severe strongyloidiasis. Adherence to current recommendations of screening among donors and recipients from endemic areas is also urgently needed.

Transplantation in the tropics: lessons on prevention and management of tropical infectious diseases

Tropical infectious diseases (IDs) remain a rare complication in transplant recipients even in tropical settings, but this topic has become increasingly important during the last decade due to multiple factors. Interestingly, non-tropical countries report most of the experiences with tropical diseases. The reported experience from non-endemic regions, however, does not always reflect the experience of endemic areas. Most of the guidelines and recommendations in the literature may not be applicable in tropical settings due to logistical difficulties, cost, and lack of proven benefit. In addition, certain post-transplant prevention measures, as prophylaxis and reducing exposure risk, are not feasible. Nonetheless, risk assessment and post-transplant management of tropical IDs in tropical areas should not be neglected, and clinicians need to have a higher clinical awareness for tropical ID occurring in this population. Herein, we review the more significant tropical ID in transplant patients, focusing on relevant experience reported by tropical settings.

Novel approaches to the diagnosis of Strongyloides stercoralis infection

Strongyloides stercoralis differs from the other soil-transmitted helminths because it puts infected subjects at risk of a fatal syndrome (in cases of immunosuppression for medical conditions, immunosuppressant therapies, or both). Chronic strongyloidiasis is often a non-severe condition, or is sometimes even asymptomatic, but diagnosis and effective therapy are essential in order to eradicate the infection and the life-long risk involved. Therefore, diagnostic methods need to be highly sensitive. Stool microscopy and the Kato-Katz technique are commonly used in prevalence studies, but they are inadequate for S. stercoralis detection. This is probably the main reason why the global prevalence has long been underestimated. Concentration methods, the Baermann technique and Koga agar plate culture have better, but still unsatisfactory, sensitivity. Serological tests have demonstrated higher sensitivity; although some authors have concerns about their specificity, it is possible to define cut-off values over which infection is almost certain. In particular, the luciferase immunoprecipitation system technique combined with a recombinant antigen (NIE) demonstrated a specificity of almost 100%. ELISA coproantigen detection has also shown promising results, but still needs full evaluation. Molecular diagnostic methods are currently available in a few referral centres as in-house techniques. In this review, on the basis of the performance of the different diagnostic methods, we outline diagnostic strategies that could be proposed for different purposes, such as: prevalence studies in endemic areas; individual diagnosis and screening; and monitoring of cure in clinical care and clinical trials.

Donor-derived Strongyloides stercoralis infection in solid organ transplant recipients in the United States, 2009-2013

Infection with Strongyloides stercoralis is typically asymptomatic in immunocompetent hosts, despite chronic infection. In contrast, immunocompromised hosts such as solid organ transplant recipients are at risk for hyperinfection syndrome and/or disseminated disease, frequently resulting in fatal outcomes. Infection in these recipients may result from reactivation of latent infection or infection through transmission from an infected donor. We describe the Centers for Disease Control and Prevention's experience with seven clusters of donor-derived infection from 2009 to 2013. Six of the seven (86%) donors were born in Latin America; donor screening was not performed prior to organ transplantation in any of these investigations. Eleven of the 20 (55%) organ recipients were symptomatic, two of whom died from complications of strongyloidiasis. We also describe the New York Organ Donor Network (NYODN) experience with targeted donor screening from 2010 to 2013. Of the 233 consented potential donors tested, 10 tested positive for Strongyloides antibody; and 18 organs were transplanted. The majority (86%) of the donors were born in Central or South America. Fourteen recipients received prophylaxis after transplantation; no recipients developed strongyloidiasis. The NYODN experience provides evidence that when targeted donor screening is performed prior to transplantation, donor-derived infection can be averted in recipients.