Strongyloides stercoralis transmission by kidney transplantation in two recipients from a common donor

Severe strongyloidiasis: a systematic review and meta-analysis of 339 cases

Strongyloidiasis is a parasitosis representing a significant public health problem in tropical countries. It is often asymptomatic in immunocompetent individuals but its mortality rate increases to approximately 87% in severe forms of the disease. We conducted a systematic review, including case reports and case series, of Strongyloides hyperinfection and dissemination from 1998 to 2020 searching PubMed, EBSCO and SciELO. Cases that met the inclusion criteria of the Preferred Reported Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist were analysed. Statistical analysis was performed using Fisher's exact test and Student's t-test and a Bonferroni correction for all the significant values. A total of 339 cases were included in this review. The mortality rate was 44.83%. The presence of infectious complications, septic shock and a lack of treatment were risk factors for a fatal outcome. Eosinophilia and ivermectin treatment were associated with an improved outcome.

Overlapping Infection by Strongyloides spp. and Cytomegalovirus in the Immunocompromised Host: A Comprehensive Review of the Literature

Strongyloides and cytomegalovirus co-infections are rarely reported, even though they are distinguished by high morbidity and mortality, especially in immunocompromised hosts. We narratively reviewed the literature on reported cases of Strongyloides and CMV co-infections in immunosuppressed patients. Most cases occurred in males with a median age of 47 (IQR, 37-59). Strongyloides/CMV co-infections occurred among immunocompromised hosts, especially in solid organ transplants and hematological or rheumatological diseases. Most of the patients underwent a course of steroid treatment before the diagnosis of co-infections. Other common immunomodulatory agents were tacrolimus and mycophenolate. The first clinical manifestations of co-infections were mainly gastrointestinal, followed by respiratory symptoms. CMV was, in most patients, co-infected with an isolated reactivation, although Strongyloides manifested especially as hyperinfection syndrome. Ganciclovir and ivermectin are the mainstays of CMV and Strongyloides treatment. However, the treatment mortality reported in this narrative review is around 52.4%. Interestingly secondary bacterial infections are common in CMV/Strongyloides-infected patients.

Strongyloides spp. and Cytomegalovirus Co-Infection in Patient Affected by Non-Hodgkin Lymphoma

To our knowledge, we have described the first case of Strongyloides/Cytomegalovirus (CMV) concomitant infection that occurred in a European country. The patient was a 76-year-old woman affected by relapsed non-Hodgkin lymphoma who presented interstitial pneumonia with a rapidly progressive worsening of respiratory insufficiency, leading to cardiac dysfunction and consequent death. CMV reactivation is a common complication in immunocompromised patients, while hyperinfection/disseminated strongyloidiasis (HS/DS) is rare in low endemic regions, but has been widely described in Southeast Asia and American countries. HS and DS are two consequences of the failure of infection control by the immune system: HS is the uncontrolled replication of the parasite within the host and DS the spreading of the L3 larvae in organs other than the usual replication sites. Only a few cases of HS/CMV infection have been reported in the literature, and only in one patient with lymphoma as an underlying disease. The clinical manifestations of these two infections overlap, usually leading to a delayed diagnosis and a consequent poor outcome.

A comprehensive review of Strongyloides stercoralis infection after solid organ and hematopoietic stem cell transplantation

BACKGROUND

We reviewed the scientific literature to gain insight on the epidemiology and outcome of Strongyloides stercoralis infections after transplantation.

METHODS

CINAHL, PUBMED, and OVID/MEDLINE were reviewed from inception through March 31, 2022 using key words Strongyloides and transplantation.

RESULTS

Our review identified 108 episodes of Strongyloides infection among 91 solid organ transplant (SOT) and 15 hematopoietic cell transplant (HCT) recipients. Median time to infection was 10.8 (range, .14-417) and 8.8 (range, 0-208) weeks after SOT and HCT, respectively. Gastrointestinal symptoms were frequent (86/108 [79.6%]), while skin rash (22/108 [20.3%]) and fever (31/103 [30%]) were less common. Peripheral eosinophilia was observed in half of patients (41/77 [53.2%]). Bacteremia (31/59 [52.5%]) was frequently due to Gram-negative organisms (24/31 [77.4%]). Abnormal chest radiologic findings were reported in half (56/108 [51.9%]). The majority had hyperinfection syndrome (97/108 [89.8%]) while disseminated strongyloidiasis was less common (11/108 [10.2%]). Thirty-two cases were categorized as donor-derived infection (DDI), with donors (23/24 [95.8%]) who had traveled to or lived in endemic areas. Median time to DDI was 8 weeks (range .5-34.3 weeks) after transplantation. Treatment consisted of ivermectin (n = 26), a benzimidazole (n = 27), or both drugs (n = 28). There was high all-cause mortality (48/107, 44.9%) and a high Strongyloides-attributable mortality (32/49, 65.3%).

CONCLUSIONS

Strongyloidiasis should be strongly considered among recipients with epidemiologic risk factors for infection, even in the absence of eosinophilia or rash. A policy that provides guidance on pro-active screening is needed, to ensure preventive measures are provided to recipients at increased risk.

Comparison of Two Serological Assays in Detecting Strongyloides Infection in Immunocompromised Patients

Strongyloides infection may develop into fatal hyperinfection and dissemination syndrome in immunocompromised hosts. Despite suboptimal specificity issues, the detection of IgG antibodies by ELISA has been central in the serodiagnosis of Strongyloides infection. Recently, an IgG4-based lateral-flow test (SsRapid) using recombinant NIE (rNIE) protein with good diagnostic performance has been reported. This study assessed the result concordance between a commercial IgG-ELISA and the SsRapid. Additionally, we determined the Strongyloides seroprevalence and its association with clinical manifestations. Immunocompromised patients (N = 200) were from Hospital Canselor Tuanku Muhriz, Kuala Lumpur, Malaysia, and were diagnosed with HIV/AIDS, hematological malignancy, and solid organ cancers. Their plasma samples were tested using a commercial IgG-ELISA and SsRapid. A fair concordance (κ = 0.27-0.33; P < 0.05) among the tests was demonstrated. The SsRapid exhibited a significantly higher (P < 0.05) seroprevalence (10.5% [21/200]) compared with IgG-ELISA (7.5% [15/200]). After adsorption with rNIE, all SsRapid-positive samples tested negative with the rapid test, thus showing binding specificity. There was no significant association with clinical manifestations. This study revealed that SsRapid is a useful diagnostic tool for Strongyloides infection, and there is a notable seroprevalence among the immunocompromised patients.

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.

Histologic features of colonic infections

Background

The histopathologic diagnosis of infectious colitis remains relevant despite recent advances in microbiologic techniques.

Objective

This article aims to describe the histologic features of selected infectious diseases of the colon.

Materials and methods

Existing reports on histopathologic and clinical aspects of colonic infectious agents were reviewed.

Results

While histology alone may not be as sensitive as current microbiologic methods, tissue identification of infectious agents still plays an important role in patient care. Infectious colitis can have a variety of clinical manifestations, ranging from strongyloidiasis, which can cause a smoldering, subclinical infection for decades, to syphilis, which can clinically mimic cancer or inflammatory bowel disease. Therefore, the histopathologic identification of infection as the cause of a patient’s colitis has a considerable impact on treatment decisions. Morphologic overlap can occur between infection and other diseases, however. Moreover, some infections can elicit various tissue responses beyond acute colitis. Immunosuppressed patients may not mount an inflammatory response to pathogens such as cytomegalovirus or adenovirus. Sexually transmitted proctocolitis can cause plasma-cell-rich inflammation. Gastrointestinal histoplasmosis is more likely to cause diffuse histiocyte infiltration rather than the expected granuloma formation. In some cases, ancillary tests are useful, but equivocal results can cause diagnostic dilemmas.

Conclusion

Given the range with which colonic infectious disorders can manifest, pathologists should be aware of the typical features of infectious colitis, as well as findings beyond the classic morphologies.

Donor-derived fatal hyperinfection strongyloidiasis in renal transplant recipient

Strongyloides stercoralis is a nematode, endemic in tropical and subtropical areas. Strongyloidiasis has been reported in recipients of hematopoietic stem cells, kidney, liver, heart, intestine, and pancreas, eventually presenting as disseminated strongyloidiasis and hyperinfection syndrome (SHS) which is associated with high mortality. We report one case of a recent renal transplant recipient, who presented with gastrointestinal and respiratory symptoms, evolving into shock. The identification of Strongyloides stercoralis in the bronchoalveolar lavage (BAL) lead us to the diagnosis of SHS. Treatment with subcutaneous ivermectin was started, however the patient did not survive. Retrospective serum donor analysis allowed us to identify the donor as the source of 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.

Characterization of a non-sexual population of Strongyloides stercoralis with hybrid 18S rDNA haplotypes in Guangxi, Southern China

Strongyloidiasis is a much-neglected but sometimes fatal soil born helminthiasis. The causing agent, the small intestinal parasitic nematode Strongyloides stercoralis can reproduce sexually through the indirect/heterogonic life cycle, or asexually through the auto-infective or the direct/homogonic life cycles. Usually, among the progeny of the parasitic females both, parthenogenetic parasitic (females only) and sexual free-living (females and males) individuals, are present simultaneously. We isolated S. stercoralis from people living in a village with a high incidence of parasitic helminths, in particular liver flukes (Clonorchis sinensis) and hookworms, in the southern Chinese province Guangxi. We determined nuclear and mitochondrial DNA sequences of individual S. stercoralis isolated from this village and from close by hospitals and we compared these S. stercoralis among themselves and with selected published S. stercoralis from other geographic locations. For comparison, we also analyzed the hookworms present in the same location. We found that, compared to earlier studies of S. stercoralis populations in South East Asia, all S. stercoralis sampled in our study area were very closely related, suggesting a recent common source of infection for all patients. In contrast, the hookworms from the same location, while all belonging to the species Necator americanus, showed rather extensive genetic diversity even within host individuals. Different from earlier studies conducted in other geographic locations, almost all S. stercoralis in this study appeared heterozygous for different sequence variants of the 18S rDNA hypervariable regions (HVR) I and IV. In contrast to earlier investigations, except for three males, all S. stercoralis we isolated in this study were infective larvae, suggesting that the sampled population reproduces predominantly, if not exclusively through the clonal life cycles. Consistently, whole genome sequencing of individual worms revealed higher heterozygosity than reported earlier for likely sexual populations of S. stercoralis. Elevated heterozygosity is frequently associated with asexual clonal reproduction.

The investigation of Strongyloides stercoralis seroprevalence in immunosupressed patients in Turkey

BACKGROUND/AIM

In immunosuppressed patients, strongyloidiasis can be lifethreatening because of hyperinfection or dissemination. Therefore, diagnosis of S. stercoralis is important in immunosuppressed patients with chronic strongyloidiasis. In this study, our objective was to investigate the presence of S. stercoralis antibodies by an ELISA method in immunosuppressed patients.

MATERIALS AND METHODS

A total of 100 immunosuppressed patients’ sera were included in the study. Forty-two of the patients were receiving immunosuppressive therapies for cancer or being treated for hematopoietic malignancies, 38 of the patients were receiving immunosuppressive drugs for rheumatic diseases, 14 were receiving immunosuppressive therapies for liver transplantation. Two of the patients were being treated for HIV infection and 4 were being treated for hypogammaglobulinemia. As control group, 50 individuals without a known disease were included in the study. The presence of IgG antibodies against S. stercoralis was investigated with a commercial ELISA kit.

RESULTS

S. stercoralis antibody test was positive in 4 of 100 (4%) sera from immunosuppressed patients. All control patients were negative for S. stercoralis.

CONCLUSIONS

Strongyloidiasis can be a lifelong chronic infection if not treated. In patients who are going to receive immunosuppressive therapy, it should be tested before treatment, as it can become a disseminated and life-threatening infectious disease.

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.

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.

Donor-derived strongyloidiasis after organ transplantation in Norway

Strongyloides stercoralis is an intestinal helminth which in humans can cause asymptomatic chronic infection maintained for decades through its auto-infective cycle. During solid organ transplantation, recipients may unintentionally receive an organ infected with strongyloides. This is a very rare complication but may have deadly outcome if not detected. We hereby report two transplant recipients whom developed Strongyloides hyperinfection syndrome after organ transplantation from the same deceased donor. Recipient 1 was kidney transplanted and presented at day 65 post engraftment with diarrhea and subsequent septicemia and gastric retention. Larvae were detected in gastric aspirate. Recipient 2 was simultaneously kidney and pancreas transplanted and presented at day 90 post engraftment also with gastric retention and septicemia. Larvae were demonstrated on duodenal biopsy and stool sample. The clinical course was complicated with severe duodenal bleedings, gastric retention, meningitis, and prolonged hospitalization. Retrospective testing of pre-transplant donor serum was positive for Strongyloides stercoralis antibodies. As a result of disease severity and gastric retention albenazole was administered via a jejunal tube and ivermectin subcutaneously in both recipients. S stercoralis was successfully eradicated and the transplants ended up with unaffected graft function. Following these two cases, we started systematic screening of all deceased donors for serum Strongyloides IgG in October 2016. After having screened 150 utilized donors one tested positive for Strongyloides, which initiated prophylactic ivermectin treatment to organ recipients. No symptoms or disease developed. Our center will continue to screen all donors as prophylactic treatment may avert this potentially lethal complication in cases of donor-derived Strongyloides infection.

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.

Severe Strongyloidiasis in Solid Organ Transplant Recipients: Should We Preventively Treat the Recipient, the Donor, or Both?

Strongyloidiasis is caused by a soil-transmitted helminth that is endemic in tropical and subtropical countries. The parasite can complete its life cycle without leaving the host, allowing autoinfection and persistence. The risk of infection in travelers is low, but the disease may become lethal following immunosuppression. In case of solid organ transplantation, the risk of donor transmission has been suspected for several years. However, the management of live donors in this context has only recently been considered, and no guidelines exist for the management of deceased donors. To highlight the complexity of diagnosing, treating, and preventing strongyloidiasis donor transmission, we describe a case of possible transmission of severe strongyloidiasis to a kidney transplant recipient with limited travel history. Taking into account the difficulty of diagnosing chronic strongyloidiasis infection and the increase in travel and immunosuppressive treatments, we recommend pragmatic management guidelines to limit the risks of infection.

Different but overlapping populations of Strongyloides stercoralis in dogs and humans-Dogs as a possible source for zoonotic strongyloidiasis

Strongyloidiasis is a much-neglected soil born helminthiasis caused by the nematode Strongyloides stercoralis. Human derived S. stercoralis can be maintained in dogs in the laboratory and this parasite has been reported to also occur in dogs in the wild. Some authors have considered strongyloidiasis a zoonotic disease while others have argued that the two hosts carry host specialized populations of S. stercoralis and that dogs play a minor role, if any, as a reservoir for zoonotic S. stercoralis infections of humans. We isolated S. stercoralis from humans and their dogs in rural villages in northern Cambodia, a region with a high incidence of strongyloidiasis, and compared the worms derived from these two host species using nuclear and mitochondrial DNA sequence polymorphisms. We found that in dogs there exist two populations of S. stercoralis, which are clearly separated from each other genetically based on the nuclear 18S rDNA, the mitochondrial cox1 locus and whole genome sequence. One population, to which the majority of the worms belong, appears to be restricted to dogs. The other population is indistinguishable from the population of S. stercoralis isolated from humans. Consistent with earlier studies, we found multiple sequence variants of the hypervariable region I of the 18 S rDNA in S. stercoralis from humans. However, comparison of mitochondrial sequences and whole genome analysis suggest that these different 18S variants do not represent multiple genetically isolated subpopulations among the worms isolated from humans. We also investigated the mode of reproduction of the free-living generations of laboratory and wild isolates of S. stercoralis. Contrary to earlier literature on S. stercoralis but similar to other species of Strongyloides, we found clear evidence of sexual reproduction. Overall, our results show that dogs carry two populations, possibly different species of Strongyloides. One population appears to be dog specific but the other one is shared with humans. This argues for the strong potential of dogs as reservoirs for zoonotic transmission of S. stercoralis to humans and suggests that in order to reduce the exposure of humans to infective S. stercoralis larvae, dogs should be treated for the infection along with their owners.

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.

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.

Strongyloides Hyperinfection in a Renal Transplant Patient: Always Be on the Lookout

We present a case of a 71-year-old Vietnamese man with chronic kidney disease secondary to adult polycystic kidney disease. He had been a prisoner of war before undergoing a successful cadaveric renal transplant in the United States. He presented to clinic one year after the transplant with gross hematuria, productive cough, intermittent chills, and weight loss. Long standing peripheral eosinophilia of 600–1200/μL triggered further evaluation. A wet mount of stool revealed Strongyloides stercoralis larvae. A computed tomography (CT) of chest showed findings suggestive of extension of the infection to the lungs. The patient was treated with a three-week course of ivermectin with complete resolution of signs, symptoms, peripheral eosinophilia, and the positive IgG serology. Strongyloides infection in renal transplant patient is very rare and often presents with hyperinfection, associated with high mortality rates. The American Transplant Society recommends pretransplant screening with stool examination and Strongyloides stercoralis antibody in recipients and donors from endemic areas or with eosinophilia. It is imperative that healthcare professionals involved in the care of these individuals be cognizant of these recommendations as it is a very preventable and treatable entity.

Helminths in organ transplantation

With transplantation becoming an increasingly routine form of treatment for diverse populations, and with international travel becoming ever more accessible and affordable, the danger of transplantation-mediated helminth infections, exacerbated by coincident immunosuppression, must be considered. In this Review, we attempt to catalogue all clinically-relevant helminthiases that have been reported to coincide with transplantation, whether by transplantation-mediated transmission, reactivation of latent infections in an immunosuppressed context, or possible de-novo infection during the immunosuppressed peritransplant period. Helminthiasis has been reported in cases of kidney, liver, bowel, pancreas, heart, lung, and stem-cell transplant, and blood transfusion. For each helminthiasis, known risk factors, symptoms, and suggested options for screening and treatment are given. We conclude that helminths are a small but important and potentially severe source of disease after transplantation, and, with options for diagnosis and treatment, these pathogens warrant greater consideration during organ implantation. The achievement of immunological tolerance using helminth-derived products is also an exciting future prospect.

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.

Seroepidemiology of Strongyloides stercoralis amongst immunocompromised patients in Southwest Iran

Strongyloidiasis is a life-threatening parasitic infection, especially in immunosuppressed patients, with death often occurring within several days. The disease has a worldwide distribution and is endemic in tropical and subtropical regions. Therefore, this study was conducted to investigate seroepidemiology of Strongyloides infection amongst immunocompromised patients in Southwest Iran. This cross-sectional study was conducted amongst a population of immunocompromised patients who were referred to health care or hospital referral centres in Ahvaz, Southwest Iran. Serum samples were tested by an enzyme immunoassay for anti-IgG Strongyloides antibody. Anti-Strongyloides stercoralis antibody was detected in 39 of 270 immunocommpromised cases, yielding a prevalence of 14.4%. No significant differences were indicated in terms of gender, age, or type of immunocompromised disorder with anti-Strongyloides stercoralis antibody levels. In conclusion, our results demonstrated high seroepidemiology of infection with this parasite in the region. Therefore, it appears immunocompromised patients should be tested for this infection using sensitive tests. However, current research underscores that strongyloidosis must not be neglected, and further assessments in high risk population are warranted.

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.

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.

Strongyloidiasis with emphasis on human infections and its different clinical forms

Strongyloidiasis (caused by Strongyloides stercoralis, and to a lesser extent by Strongyloides fuelleborni) is one of the most neglected tropical diseases with endemic areas and affecting more than 100 million people worldwide. Chronic infections in endemic areas can be maintained for decades through the autoinfective cycle with the L3 filariform larvae. In these endemic areas, misdiagnosis, inadequate treatment and the facilitation of the hyperinfection syndrome by immunosuppression are frequent and contribute to a high mortality rate. Despite the serious health impact of strongyloidiasis, it is a neglected disease and very little is known about this parasite and the disease when compared to other helminth infections. Control of the disease is difficult because of the many gaps in our knowledge of strongyloidiasis. We examine the recent literature on different aspects of strongyloidiasis with emphasis in those aspects that need further research.

Hyperinfection strongyloidiasis in renal transplant recipients

Strongyloidiasis is infection caused by the nematode Strongyloides stercoralis. Chronic uncomplicated strongyloidiasis is known to occur in immunocompetent individuals while hyperinfection and dissemination occurs in selective immunosuppressed hosts particularly those on corticosteroid therapy. We report two cases of hyperinfection strongyloidiasis in renal transplant recipients and document endoscopic and pathological changes in the involved small bowel. One patient presented with features of dehydration and malnutrition while another developed ileal obstruction and strangulation, requiring bowel resection. Oesophagogastroduodenoscopy showed erythematous and thickened duodenal mucosal folds. Histopathological examination of duodenal biopsies revealed S. stercoralis worms, larvae and eggs embedded in mucosa and submucosa. Wet mount stool preparation showed filariform larvae of S. stercoralis in both cases. Patients were managed with anthelmintic therapy (ivermectin/albendazole) and concurrent reduction of immunosuppression. Both patients had uneventful recovery. Complicated strongyloidiasis should be suspected in immunocompromised hosts who present with abdominal pain, vomiting and diarrhoea, particularly in endemic areas.

Strangulated Small Bowel Obstruction After Renal Transplant With No History of Laparotomy: Case Report

Strangulated small bowel obstruction is a complication after abdominal surgery, which is rare in renal transplant patients. A 61-year-old man with a strangulated small bowel obstruction underwent renal transplant surgery 7 years before the current admission. He was admitted to our hospital for abdominal pain, nausea, and abdominal distention. An abdominal computed tomography and an ultrasound examination showed intestinal expansion and fluid collection without ascites. His disease was diagnosed as a small bowel obstruction and conservative treatment was begun. However, because of increasing abdominal pain and the collection of ascites, he underwent an emergency laparotomy and was diagnosed as having a strangulated small bowel obstruction. A fibrous cord had formed between the peritoneum (beside the transplanted kidney) and the root of the sigmoid mesocolon, strangulating the looped ileum and causing bleeding necrosis and hemorrhagic ascites collection. The cord and the necrotic ileum were resected, followed by an end-to-end anastomosis. He was discharged 17 days after the surgery in good condition. This is the first reported case of a person having a strangulated small bowel obstruction by a fibrous cord, who did not have a history of laparotomy after renal transplant. A strangulated small bowel obstruction after a renal transplant in a patient with no history of a laparotomy is a rare, but possible postoperative complications should be considered when making a differential diagnosis.

Selecting suitable solid organ transplant donors: Reducing the risk of donor-transmitted infections

Selection of the appropriate donor is essential to a successful allograft recipient outcome for solid organ transplantation. Multiple infectious diseases have been transmitted from the donor to the recipient via transplantation. Donor-transmitted infections cause increased morbidity and mortality to the recipient. In recent years, a series of high-profile transmissions of infections have occurred in organ recipients prompting increased attention on the process of improving the selection of an appropriate donor that balances the shortage of needed allografts with an approach that mitigates the risk of donor-transmitted infection to the recipient. Important advances focused on improving donor screening diagnostics, using previously excluded high-risk donors, and individualizing the selection of allografts to recipients based on their prior infection history are serving to increase the donor pool and improve outcomes after transplant. This article serves to review the relevant literature surrounding this topic and to provide a suggested approach to the selection of an appropriate solid organ transplant donor.

Molecular diagnosis in clinical parasitology: When and why?

Microscopic detection and morphological identification of parasites from clinical specimens are the gold standards for the laboratory diagnosis of parasitic infections. The limitations of such diagnostic assays include insufficient sensitivity and operator dependence. Immunoassays for parasitic antigens are not available for most parasitic infections and have not significantly improved the sensitivity of laboratory detection. Advances in molecular detection by nucleic acid amplification may improve the detection in asymptomatic infections with low parasitic burden. Rapidly accumulating genomic data on parasites allow the design of polymerase chain reaction (PCR) primers directed towards multi-copy gene targets, such as the ribosomal and mitochondrial genes, which further improve the sensitivity. Parasitic cell or its free circulating parasitic DNA can be shed from parasites into blood and excreta which may allow its detection without the whole parasite being present within the portion of clinical sample used for DNA extraction. Multiplex nucleic acid amplification technology allows the simultaneous detection of many parasitic species within a single clinical specimen. In addition to improved sensitivity, nucleic acid amplification with sequencing can help to differentiate different parasitic species at different stages with similar morphology, detect and speciate parasites from fixed histopathological sections and identify anti-parasitic drug resistance. The use of consensus primer and PCR sequencing may even help to identify novel parasitic species. The key limitation of molecular detection is the technological expertise and expense which are usually lacking in the field setting at highly endemic areas. However, such tests can be useful for screening important parasitic infections in asymptomatic patients, donors or recipients coming from endemic areas in the settings of transfusion service or tertiary institutions with transplantation service. Such tests can also be used for monitoring these recipients or highly immunosuppressed patients, so that early preemptive treatment can be given for reactivated parasitic infections while the parasitic burden is still low.