Strongyloides stercoralis prevalence in solid-organ and haematopoietic stem cell transplant candidates and recipients: a systematic review and meta-analysis protocol.

INTRODUCTION: Strongyloides stercoralis is an intestinal helminth ubiquitous in tropical and subtropical regions worldwide. It persists in the human host for a lifetime as a result of autoinfection and if undetected and untreated, can lead to increased morbidity and high mortality in immunocompromised individuals such as the transplant population. Transplant patients, including solid-organ and haematopoietic stem cell transplants (SOT and HSCT, respectively), are at a high risk of hyperinfection and disseminated strongyloidiasis. Unfortunately screening is often not systematically performed. Prevalence estimates of Strongyloides in this high-risk population is not well studied. Through this systematic review, we aim to summarise the descriptive evidence on Strongyloides prevalence in SOT and HSCT patients, including diagnostic and screening practices alongside the cases of hyperinfection, disseminated strongyloidiasis and the mortality rate in this population. METHODS AND ANALYSES: Through the use of various online library databases, we will conduct a systematic review including relevant literature on the prevalence of Strongyloides in SOT and HSCT patients as well as studies assessing hyperinfection and disseminated strongyloidiasis in this patient population. The Population, Intervention, Comparison, Outcome and Study Design strategy and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines will be used to determine a final subset of studies for analysis. Quality assessment for case series and case reports will be determined by a modified quality assessment tool developed by the National Heart, Lung, and Blood Institute (NIH), and the CARE guidelines, respectively. We will provide a narrative synthesis of the findings pertaining to the primary and secondary outcomes of interest (prevalence of Strongyloides and mortality rate in transplant population, respectively) alongside the associated 95% CI. Estimates from individual studies will be pooled using a random effects model. ETHICS AND DISSEMINATION: This systematic review does not require formal ethical approval since no primary data will be collected. Findings will be disseminated through a peer-reviewed publication and relevant conferences. PROSPERO REGISTRATION NUMBER: CRD42021269305.

Poor outcome and high prevalence of invasive fungal infections in patients with adult T-cell leukemia/lymphoma exposed to zidovudine and interferon alfa.

Patients treated for adult T-Cell leukemia/lymphoma (ATL) have a poor prognosis and are prone to infectious complications which are poorly described. As the French reference center for ATL, we retrospectively analyzed 47 consecutive ATL (acute, n = 23; lymphoma, n = 14; chronic, n = 8; smoldering, n = 2) patients between 2006 and 2016 (median age 51 years, 96% Afro-Caribbean origin). The 3-year overall survival (OS) was 15.8%, 11.3%, and 85.7% for acute, lymphoma, and indolent (chronic and smoldering) forms respectively. Among aggressive subtypes, 20 patients received, as frontline therapy, high dose of zidovudine and interferon alfa (AZT-IFN⍺) resulting in an overall response rate (ORR) of 39% (complete response [CR] 33%) and 17 chemotherapy resulting of an ORR of 59% (CR 50%). Ninety-five infections occurred in 38 patients, most of whom had an acute subtype (n = 73/95; 77%). During their follow-up, patients receiving frontline chemotherapy or frontline AZT-IFNα developed infections in 74% (n = 14/19) and 89% (n = 24/27) of the cases respectively. Sixty-four (67%) of infections were microbiologically documented. Among them, invasive fungal infections (IFI, n = 11) included 2 Pneumocystis jirovecii pneumonia, 5 invasive aspergillosis, and 4 yeast fungemia. IFI exclusively occurred in patients with acute subtype mostly exposed to AZT-IFNα (n = 10/11) and experiencing prolonged (> 10 days) grade 4 neutropenia. Patients with aggressive subtype experiencing IFI had a lower OS than those who did not (median OS 5.4 months versus 18.4 months, p = 0.0048). ATL patients have a poor prognosis even in the modern era. Moreover, the high rate of infections impacts their management especially those exposed to AZT-IFNα.

Dexamethasone and COVID-19: Strategies in Low- and Middle-Income Countries to Tackle Steroid-Related Strongyloides Hyperinfection.

COVID-19 can trigger a systemic inflammatory response that in some cases leads to severe lung involvement, multisystem dysfunction, and death. Dexamethasone therapy, because of its potent anti-inflammatory effects, has been proposed for the management of hospitalized patients with severe COVID-19. The subject of this article is to discuss potential strategies to tackle Strongyloides hyperinfection in hospitalized patients with COVID-19 receiving dexamethasone therapy in low- and middle-income countries. In this context, dexamethasone treatment has been found to be generally safe. However, its use in people coinfected with undetected Strongyloides stercoralis increases the risk for Strongyloides hyperinfection/dissemination a potentially fatal complication. Infection caused by S. stercoralis may remain asymptomatic or with mild symptoms in humans for several years. Early detection and specific treatment prevent a fatal evolution of this complication, but the challenge is to screen before corticosteroid therapy. In some cases, presumptive treatment may be justified. Ivermectin is the gold standard for treatment.

HTLV-I and Strongyloides in Australia: The worm lurking beneath.

Strongyloidiasis and HTLV-I (human T-lymphotropic virus-1) are important infections that are endemic in many countries around the world with an estimated 370 million infected with Strongyloides stercoralis alone, and 5-10 million with HTVL-I. Co-infections with these pathogens are associated with significant morbidity and can be fatal. HTLV-I infects T-cells thus causing dysregulation of the immune system which has been linked to dissemination and hyperinfection of S. stercoralis leading to bacterial sepsis which can result in death. Both of these pathogens are endemic in Australia primarily in remote communities in Queensland, the Northern Territory, and Western Australia. Other cases in Australia have occurred in immigrants and refugees, returned travellers, and Australian Defence Force personnel. HTLV-I infection is lifelong with no known cure. Strongyloidiasis is a long-term chronic disease that can remain latent for decades, as shown by infections diagnosed in prisoners of war from World War II and the Vietnam War testing positive decades after they returned from these conflicts. This review aims to shed light on concomitant infections of HTLV-I with S. stercoralis primarily in Australia but in the global context as well.

Strongyloides infection manifested during immunosuppressive therapy for SARS-CoV-2 pneumonia.

BACKGROUND: SARS-CoV-2 pandemic has posed formidable public health and clinical challenges. The use of immunosuppressive agents, such as high dose corticosteroids and cytokine inhibitors (e.g., Tocilizumab) has been suggested to contrast the hyperinflammatory process involved in the pathogenesis of the severe disease, with conflicting evidence. Among the drawbacks of immunosuppressive therapy, the risk of reactivation of latent infections, including parasitic infestations, is to be considered. CASE PRESENTATION: We report a case of a 59-year-old Italian patient treated with high dose intravenous dexamethasone and two intravenous doses of Tocilizumab for interstitial bilateral pneumonia associated with SARS-CoV-2 infection who developed itching, abdominal pain, and an increased eosinophil count. Stool examination confirmed the presence of S. stercoralis larvae. The patient was treated with a 4-day course of Ivermectin with full recovery. DISCUSSION: We report the first case of S. stercoralis infection following an 11-day treatment with high-dose steroids and Tocilizumab for severe COVID-19. Clinicians should be aware of the risk of strongyloidiasis as a complication of the treatment for severe COVID-19.

Strongyloides hyperinfection in an HIV-positive kidney transplant recipient: a case report.

BACKGROUND: Strongyloidiasis is caused by the helminth Strongyloides stercoralis and is well-recognised amongst transplant recipients. Serious complications, including Strongyloides hyperinfection which is a syndrome of accelerated autoinfection, or disseminated disease, can occur post-transplantation, resulting in significant morbidity and mortality. Here we present the first published case we are aware of, describing post-transplant Strongyloides hyperinfection in an HIV-positive kidney transplant patient. We discuss the diagnostic challenges and the role of pre-transplant screening. CASE PRESENTATION: A 58-year-old African-American male, originally from the Caribbean, received a deceased donor kidney transplant for presumed focal segmental glomerulosclerosis. He was known to be HIV-positive, with a stable CD4 count, and an undetectable viral load. Five months post-transplant, he developed gastrointestinal symptoms and weight loss. He had a normal eosinophil count (0.1-0.2 × 109/L), negative serum cytomegalovirus DNA, and negative blood and stool cultures. His Strongyloides serology remained negative throughout. A diagnosis of Strongyloides hyperinfection was made by the histological examination of his duodenum and lung, which identified the parasites. He completed his course of treatment with Ivermectin but exhibited profound deconditioning and required a period of total parenteral nutrition. He was subsequently discharged after a prolonged hospital admission of 54 days. CONCLUSIONS: This case highlights the challenges in diagnosing Strongyloides infection and the need to maintain a high index of clinical suspicion. Non-invasive techniques for the diagnosis of Strongyloides may be insufficient. Routine pre-transplant serological strongyloidiasis screening is now performed at our centre.

Epidemiology and risk factors of Strongyloides stercoralis infection in Papua, Indonesia: a molecular diagnostic study.

Strongyloides stercoralis is a parasitic worm that is of considerable clinical relevance. Indeed, it may persist asymptomatically for many years, but can lead to potentially fatal dissemination when the host's immune status is impaired. As commonly employed stool microscopy techniques (e.g. Kato-Katz thick smear) fail to detect S. stercoralis, the epidemiology is poorly understood. In 2013, we conducted a cross-sectional household survey in the district of Mimika in Papua, Indonesia. A total of 331 individuals, aged 1 month to 44 years, had a single stool sample subjected to real-time polymerase chain reaction (PCR) for S. stercoralis diagnosis. The prevalence of S. stercoralis infection was 32.0% (106/331 individuals); higher than any of the three main soil-transmitted helminths (Ascaris lumbricoides, 23.9%; Trichuris trichiura, 18.4%; and hookworm, 17.2%). Amongst the S. stercoralis-infected individuals, 73.6% were concurrently infected with another helminth, with hookworm being the most frequent co-infection (27.4%). Fourteen percent of the S. stercoralis infections had low cycle threshold values on real-time PCR, which may indicate a higher infection intensity. Multivariate logistic regression analysis revealed that age ≥5 years (adjusted odds ratio (OR) 5.8, 95% confidence interval (CI): 3.1-10.8) was significantly associated with S. stercoralis infection. There is a need for in-depth clinical and diagnostic studies to elucidate the public health impact of S. stercoralis infection in Indonesia.

Clinical Characteristics of Disseminated Strongyloidiasis, Japan, 1975-2017.

Clinical characteristics of disseminated strongyloidiasis, the severest form of strongyloidiasis, are not well described. We conducted a retrospective, consecutive chart review of patients with disseminated strongyloidiasis admitted to Okinawa Chubu Hospital in Okinawa, Japan, during January 1975-December 2017. The 70 patients were classified into 3 clinical phenotypes: dissemination (32 patients [45.7%]), occult dissemination with meningitis caused by enteric organisms (12 patients [17.1%]), and occult dissemination with culture-negative suppurative meningitis (26 patients [37.1%]). Associated mortality rates were 56.3%, 16.7%, and 11.5%, respectively, and sepsis occurred in 40.6%, 58.3%, and 11.5% of cases, respectively. Common symptoms included fever (52.9% of patients), headache (32.9%), and altered mental status (24.3%). Patients were treated with thiabendazole (before 2003) or ivermectin (after 2003). Our findings show that disseminated strongyloidiasis has clinical phenotypes in terms of severity and that identification of occult dissemination, a mild form with prominent neurologic manifestations, is lifesaving.

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.

Intestinal parasites including Cryptosporidium, Cyclospora, Giardia, and Microsporidia, Entamoeba histolytica, Strongyloides, Schistosomiasis, and Echinococcus: Guidelines from the American Society of Transplantation Infectious Diseases Community of Practice.

These updated guidelines from the Infectious Diseases Community of Practice of the American Society of Transplantation review the diagnosis, prevention, and management of intestinal parasites in the pre- and post-transplant period. Intestinal parasites are prevalent in the developing regions of the world. With increasing travel to and from endemic regions, changing immigration patterns, and the expansion of transplant medicine in developing countries, they are increasingly recognized as a source of morbidity and mortality in solid-organ transplant recipients. Parasitic infections may be acquired from the donor allograft, from reactivation, or from de novo acquisition post-transplantation. Gastrointestinal multiplex assays have been developed; some of the panels include testing for Cryptosporidium, Cyclospora, Entamoeba histolytica, and Giardia, and the performance is comparable to conventional methods. A polymerase chain reaction test, not yet widely available, has also been developed to detect Strongyloides in stool samples. New recommendations have been developed to minimize the risk of Strongyloides donor-derived events. Deceased donors with epidemiological risk factors should be screened for Strongyloides and recipients treated if positive as soon as the results are available. New therapeutic agents and studies addressing the optimal treatment regimen for solid-organ transplant recipients are unmet needs.

Parasitic Infections of the Stem Cell Transplant Recipient and the Hematologic Malignancy Patient, Including Toxoplasmosis and Strongyloidiasis.

Hematopoietic stem cell transplantation (HSCT) recipients may infrequently develop parasitic infections at the time of the procedure via contamination from allograft tissue or blood products, and in the post-transplantation period through the traditional route of infection or as a reactivation caused by immunosuppression related to the transplant. To reduce risk, efforts should be directed at performing a comprehensive history, maintaining a high index of suspicion, and adhering to preventive measures. Additional strategies for the prevention, screening and careful follow-up, identification, and pre-emptive treatment of parasitic infections are required to reduce morbidity and mortality in HSCT patients.

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.

Terminal ileum resection as a trigger for Strongyloides stercoralis hyperinfection and ensuing serial sepsis in a 37-year-old patient with complicated Crohn's disease: a case report.

The nematode Strongyloides stercoralis, outside the tropics and subtropics present in small endemic foci, can cause an infection after direct skin contact with contaminated soil containing infective filariform larvae and, rarely, after intimate interhuman contact or after transplantation of an infected solid organ. Following skin penetration, migration, and maturation through several stages, a small number of invasive filariform larvae can develop anew in the gut lumen, perpetuating new cycles of penetration, tissue migration, and reproduction, without leaving the host.In a state of immunosuppression, autoinfection can progress to life-threatening hyperinfection and/or infection disseminated through virtually any organ. In developed countries, the most frequently recognized risk for severe hyperinfection is corticosteroid therapy, but this has been also described in malnourished, alcoholic, cancer, and transplant patients. Due to the frequent need for immunosuppressive therapy, patients suffering from inflammatory bowel disease (IBD) are susceptible to develop overwhelming strongyloidiasis. Strongyloidiasis can be easily overlooked in clinical settings, and in many European regions there is poor insight into the epidemiological burden of this disease.We present a case of S. stercoralis hyperinfection that triggered 3 successive episodes of sepsis caused by pathogens of the gut flora in a young patient suffering from stenotic form of Crohn's disease. S. stercoralis hyperinfection occurred in the corticosteroid-free period, shortly after resection of the terminal ileum, which was probably the trigger for the overwhelming course. The patient was successfully treated with 10-day albendazole therapy.

Disseminated Strongyloidiasis.

Strongyloidiasis is a parasitic infestation caused by the helminth Strongyloides stercoralis. It is essentially gastrointestinal and in general asymptomatic but can sometimes present with skin signs. Immunocompromised patients can develop the disseminated form of the disease due to the parasite's opportunistic behavior, as in cases of coinfection by the human T-lymphotropic type 1 virus (HTLV-1). This article presents a case of a patient infected with HTLV-I and Strongyloides stercoralis who developed the disseminated form. There were purpuric reticulated periumbilical lesions as well as vibices on the patient's flanks. Histopathologic exam of a skin lesion revealed the presence of larvae in the deep reticular dermis. We emphasize the relevance of awareness regarding interaction between HTLV-1 and strongyloidiasis, besides identification of the cutaneous manifestations of the disease to reach an appropriate therapeutic diagnosis.

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.

Pulmonary strongyloidiasis: assessment between manifestation and radiological findings in 16 severe strongyloidiasis cases.

BACKGROUND: Strongyloidiasis is a chronic parasitic infection caused by Strongyloides stercoralis. Severe cases such as, hyperinfection syndrome (HS) and disseminated strongyloidiasis (DS), can involve pulmonary manifestations. These manifestations frequently aid the diagnosis of strongyloidiasis. Here, we present the pulmonary manifestations and radiological findings of severe strongyloidiasis. METHODS: From January 2004 to December 2014, all patients diagnosed with severe strongyloidiasis at the University of the Ryukyus Hospital or affiliated hospitals in Okinawa, Japan, were included in this retrospective study. All diagnoses were confirmed by the microscopic or histopathological identification of larvae. Severe strongyloidiasis was defined by the presence of any of the following: 1) the identification of S. stercoralis from extra gastrointestinal specimens, 2) sepsis, 3) meningitis, 4) acute respiratory failure, or 5) respiratory tract hemorrhage. Patients were assigned to either HS or DS. Medical records were further reviewed to extract related clinical features and radiological findings. RESULTS: Sixteen severe strongyloidiasis cases were included. Of those, fifteen cases had pulmonary manifestations, eight had acute respiratory distress syndrome (ARDS) (53%), seven had enteric bacterial pneumonia (46%) and five had pulmonary hemorrhage (33%). Acute respiratory failure was a common indicator for pulmonary manifestation (87%). Chest X-ray findings frequently showed diffuse shadows (71%). Additionally, ileum gas was detected for ten of the sixteen cases in the upper abdomen during assessment with chest X-ray. While, chest CT findings frequently showed ground-glass opacity (GGO) in 89% of patients. Interlobular septal thickening was also frequently shown (67%), always accompanying GGO in upper lobes. CONCLUSIONS: In summary, our study described HS/DS cases with pulmonary manifestations including, ARDS, bacterial pneumonia and pulmonary hemorrhage. Chest X-ray findings in HS/DS cases frequently showed diffuse shadows, and the combination of GGO and interlobular septal thickening in chest CT was common in HS/DS, regardless of accompanying pulmonary manifestations. This CT finding suggests alveolar hemorrhage could be used as a potential marker indicating the transition from latent to symptomatic state. Respiratory specimens are especially useful for detecting larvae in cases of HS/DS.

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.