Cardiovascular Management of Patients Undergoing Hematopoietic Stem Cell Transplantation: From Pretransplantation to Survivorship: A Scientific Statement From the American Heart Association.

Hematopoietic stem cell transplantation can cure various disorders but poses cardiovascular risks, especially for elderly patients and those with cardiovascular diseases. Cardiovascular evaluations are crucial in pretransplantation assessments, but guidelines are lacking. This American Heart Association scientific statement summarizes the data on transplantation-related complications and provides guidance for the cardiovascular management throughout transplantation. Hematopoietic stem cell transplantation consists of 4 phases: pretransplantation workup, conditioning therapy and infusion, immediate posttransplantation period, and long-term survivorship. Complications can occur during each phase, with long-term survivors facing increased risks for late effects such as cardiovascular disease, secondary malignancies, and endocrinopathies. In adults, arrhythmias such as atrial fibrillation and flutter are the most frequent acute cardiovascular complication. Acute heart failure has an incidence ranging from 0.4% to 2.2%. In pediatric patients, left ventricular systolic dysfunction and pericardial effusion are the most common cardiovascular complications. Factors influencing the incidence and risk of complications include pretransplantation therapies, transplantation type (autologous versus allogeneic), conditioning regimen, comorbid conditions, and patient age. The pretransplantation cardiovascular evaluation consists of 4 steps: (1) initial risk stratification, (2) exclusion of high-risk cardiovascular disease, (3) assessment of cardiac reserve, and (4) optimization of cardiovascular reserve. Clinical risk scores could be useful tools for the risk stratification of adult patients. Long-term cardiovascular management of hematopoietic stem cell transplantation survivors includes optimizing risk factors, monitoring, and maintaining a low threshold for evaluating cardiovascular causes of symptoms. Future research should prioritize refining risk stratification and creating evidence-based guidelines and strategies to optimize outcomes in this growing patient population.

Sex-Specific Cardiovascular Risks of Cancer and Its Therapies.

In both cardiovascular disease and cancer, there are established sex-based differences in prevalence and outcomes. Males and females may also differ in terms of risk of cardiotoxicity following cancer therapy, including heart failure, cardiomyopathy, atherosclerosis, thromboembolism, arrhythmias, and myocarditis. Here, we describe sex-based differences in the epidemiology and pathophysiology of cardiotoxicity associated with anthracyclines, hematopoietic stem cell transplant (HCT), hormone therapy and immune therapy. Relative to males, the risk of anthracycline-induced cardiotoxicity is higher in prepubertal females, lower in premenopausal females, and similar in postmenopausal females. For autologous hematopoietic cell transplant, several studies suggest an increased risk of late heart failure in female lymphoma patients, but sex-based differences have not been shown for allogeneic hematopoietic cell transplant. Hormone therapies including GnRH (gonadotropin-releasing hormone) modulators, androgen receptor antagonists, selective estrogen receptor modulators, and aromatase inhibitors are associated with cardiotoxicity, including arrhythmia and venous thromboembolism. However, sex-based differences have not yet been elucidated. Evaluation of sex differences in cardiotoxicity related to immune therapy is limited, in part, due to low participation of females in relevant clinical trials. However, some studies suggest that females are at increased risk of immune checkpoint inhibitor myocarditis, although this has not been consistently demonstrated. For each of the aforementioned cancer therapies, we consider sex-based differences according to cardiotoxicity management. We identify knowledge gaps to guide future mechanistic and prospective clinical studies. Furthering our understanding of sex-based differences in cancer therapy cardiotoxicity can advance the development of targeted preventive and therapeutic cardioprotective strategies.

Colorectal Cancer Risk and Recommendations for Colorectal Cancer Surveillance in Adult Survivors of Childhood Cancer.

While many organizations have published guidance on the approach to colorectal cancer (CRC) screening in average-risk and certain high-risk groups, adult survivors of childhood cancer (ASCC) who have a heightened risk of CRC are rarely included as a target group for enhanced CRC surveillance. The population of ASCC continues to grow due to increasingly effective cancer therapies and improved survival. With this increased survival comes an increased risk for subsequent malignant neoplasms, including CRC. Since there is little published guidance for CRC surveillance in ASCC and limited awareness of increased CRC risk among both physicians and patients, the objectives of our paper are to review the incidence of and risk factors for colorectal neoplasia in ASCC, describe the clinical phenotypes of colorectal neoplasia in ASCC, review published surveillance strategies based on consensus-based survivorship guidelines, and outline areas for future research to optimize surveillance strategies.

Reproductive late effects after hematopoietic stem cell transplant in pediatric, adolescent, and young adult cancer survivors.

Reproductive late effects after hematopoietic stem cell transplant can have a significant impact on cancer survivors' quality of life. Potential late effects include gonadal insufficiency, genital graft-versus-host disease, uterine injury, psychosexual dysfunction, and an increased risk of breast and cervical cancer in patients treated with total body irradiation. Despite guidelines, screening and treatment are not standardized among at-risk patients. Provider barriers include lack of knowledge of at-risk therapies and evidenced-based guidelines. Patient barriers include a reluctance to report symptoms and lack of awareness of treatment options. System barriers include inefficient implementation of screening tools and poor dissemination of guidelines to providers who serve as the medical home for survivors. This review guides the clinician in identifying and managing reproductive late effects after hematopoietic stem cell transplant to improve outcomes.

Fertility assessment and treatment in adolescent and young adult cancer survivors.

In the survivorship setting, adolescent and young adult (AYA) cancer survivors frequently demonstrate little knowledge of infertility risk, are unclear regarding their fertility status, and may under- or overestimate their treatment-related risk for infertility. In female AYA survivors, ovarian function usually parallels fertility, and can be assessed with serum hormone levels and ultrasonography. Posttreatment fertility preservation may be appropriate for survivors at risk for primary ovarian insufficiency. In male AYA survivors, fertility and gonadal function are not always equally affected, and can be assessed with a semen analysis and serum hormones, respectively. As reproductive health issues are commonly cited as an important concern by survivors of AYA cancer, multidisciplinary care teams including oncology, endocrinology, psychology, and reproductive medicine are advocated, with the aim of optimal provision of fertility advice and care for AYA cancer survivors.

Targeted cancer treatment and fertility: effect of immunotherapy and small molecule inhibitors on female reproduction.

Targeted cancer therapy is rapidly evolving the landscape of personalized health care. Novel approaches to selectively impeding tumour growth carry significant potential to improve survival outcomes, particularly for reproductive-aged patients harbouring treatment refractory disease. Current agents fall within two classes: immunotherapy and small molecule inhibitors. These are collectively divided into the following subclasses: monoclonal antibodies; immunomodulators; adoptive cell therapy; treatment vaccines; kinase inhibitors; proteasome inhibitors; metalloproteinase and heat shock protein inhibitors; and promoters of apoptosis. The short- and long-term effects of these treatments on the female reproductive system are not well understood. As a result, clinicians are rendered unable to appropriately counsel women on downstream effects to their fertility. Data-driven consensus recommendations are desperately needed. This review aims to characterize the effect of targeted cancer therapy on the female hypothalamic-pituitary-ovary axis, direct ovarian function and conception.

Fecal microbiota of adolescent and young adult cancer survivors and metabolic syndrome: an exploratory study.

Metabolic syndrome and obesity occur commonly in long-term pediatric cancer survivors. The intestinal microbiome is associated with metabolic syndrome and obesity in the general population, and is perturbed during cancer therapy. We aimed to determine if long-term survivors of pediatric cancer would have reduced bacterial microbiome diversity, and if these findings would be associated with components of the metabolic syndrome, obesity, and chronic inflammation. We performed a cross-sectional exploratory study examining the intestinal microbiome via 16S amplicon sequencing, treatment history, clinical measurements (blood pressure, body mass index) and biomarkers (hemoglobin A1c, lipoproteins, adiponectin: leptin ratio, C-reactive protein, TNFα, Interleukin-6, and Interleukin-10) between 35 long-term survivors and 32 age, sex, and race matched controls. All subjects were aged 10-40 years, and survivors were at least five years from therapy completion. Survivors had lower alpha diversity compared to controls (Shannon index p = .001, Simpson index p = .032) and differently abundant bacterial taxa. Further, among survivors, those who received radiation (18/35) to the central nervous system or abdomen/pelvis had decreased alpha diversity compared to those who did not receive radiation (Shannon and Simpson p < .05 for both). Although, no specific component of metabolic syndrome or cytokine was associated with measures of alpha diversity, survivors with low adiponectin-lectin ratio, elevated body mass index, and elevated C-reactive protein had differently abundant taxa compared to those with normal measures. The microbiome of cancer survivors remains less diverse than controls even many years after diagnosis, and exposure to radiation may lead to further loss of diversity in survivors.Supplemental data for this article is available online at https://doi.org/10.1080/08880018.2022.2049937.

The ASH-ASPHO Choosing Wisely Campaign: 5 hematologic tests and treatments to question.

Choosing Wisely is a medical stewardship and quality-improvement initiative led by the American Board of Internal Medicine Foundation in collaboration with leading medical societies in the United States. The American Society of Hematology (ASH) has been an active participant in the Choosing Wisely project. In 2019, ASH and the American Society of Pediatric Hematology/Oncology (ASPHO) formed a joint task force to solicit, evaluate, and select items for a pediatric-focused Choosing Wisely list. By using an iterative process and an evidence-based method, the ASH-ASPHO Task Force identified 5 hematologic tests and treatments that health care providers and patients should question because they are not supported by evidence, and/or they involve risks of medical and financial costs with low likelihood of benefit. The ASH-ASPHO Choosing Wisely recommendations are as follows: (1) avoid routine preoperative hemostatic testing in an otherwise healthy child with no previous personal or family history of bleeding, (2) avoid platelet transfusion in asymptomatic children with a platelet count 10 × 103 /µL unless an invasive procedure is planned, (3) avoid thrombophilia testing in children with venous access-associated thrombosis and no positive family history, (4) avoid packed red blood cells transfusion for asymptomatic children with iron deficiency anemia and no active bleeding, and (5) avoid routine administration of granulocyte colony-stimulating factor for prophylaxis of children with asymptomatic autoimmune neutropenia and no history of recurrent or severe infections. We recommend that health care providers carefully consider the anticipated risks and benefits of these identified tests and treatments before performing them.

Cardiovascular disease and its management in children and adults undergoing hematopoietic stem cell transplantation.

Hematopoietic stem cell transplantation (HSCT) is a potentially curative treatment for many malignancies, hemoglobinopathies, metabolic diseases, bone marrow failure syndromes, and primary immune deficiencies. Despite the significant improvement in survival afforded by HSCT, the therapy is associated with major short and long-term morbidity and mortality. Cardiovascular complications such as cardiomyopathy, arrhythmias, pulmonary hypertension, and pericardial effusions are increasingly recognized as potential outcomes following HSCT. The incidence of cardiac complications is related to various factors such as age, co-morbid medical conditions, whether patients received cardiotoxic chemotherapy prior to HSCT, the type of HSCT (autologous versus allogeneic), and the specific conditioning regimen. Thus, the cardiovascular evaluation has become a core component of the pre-transplant assessment, however, the practice differs from center to center as national guidelines and contemporary high-quality studies are lacking. We review the incidence of cardiotoxicity in pediatric and adult HSCT, potential mechanisms of injury, and effects on long-term outcomes. We also discuss the possible therapeutic approaches when disease arises, as well as the indications and need for surveillance before, during, and after transplantation.

Heterozygous CTLA4 splice site mutation c.458-1G > C presenting with immunodeficiency and variable degree of immune dysregulation in three generation kindred of Caribbean descent.

Cytotoxic T-lymphocyte-associated protein 4 (CTLA4) is an immune checkpoint, which downregulates T cell activation and T regulatory cell function. CTLA4 haploinsufficiency (CTLA4 HI) leads to T cell hyperactivation, immunodeficiency and variable degree of immune dysregulation. Furthermore, CTLA4 HI predisposes affected individuals to development of various cancers. Less well understood is the penetrance and expressivity of CTLA4 mutations. We describe five members of a single family with heterozygous CTLA4 splice site mutation c.458-1G > C, previously shown to result in CTLA-4 HI, who presented with immunodeficiency and variable degree of immune dysregulation. The host, environmental and the epigenetic factors affecting the penetrance and expressivity of CTLA4 mutations merits further investigation.

Use of Thrombopoietin Receptor Agonists in Prolonged Thrombocytopenia after Hematopoietic Stem Cell Transplantation.

Prolonged thrombocytopenia after hematopoietic stem cell transplantation (HSCT) is a strong risk factor for transplantation-related morbidity and mortality, and no standard treatment guideline exists. Thrombopoietin receptor agonists (TPO-RAs), eltrombopag and romiplostim, increases the platelet production, and are being increasingly used in various conditions with thrombocytopenia. In this review, we present an overview of these TPO-RAs and review their efficacy and safety in prolonged post-HSCT thrombocytopenia. Through a systematic literature search, we identified 25 reports describing their use for this indication. Thirteen reports (8 case series and 5 case reports) described the use of eltrombopag in 78 patients with prolonged isolated thrombocytopenia (PIT) and 43 patients with secondary failure of platelet recovery (SFPR). A consistent and durable response with a rise in platelet counts >50 × 10 9/L for 7 consecutive days without platelet transfusion was seen in 85 of 121 patients (overall response rate [ORR], 70%). The responders included 56 patients with PIT (ORR for PIT, 72%) and 29 patients with SFPR (ORR for SFPR, 67%). No serious grade 3 or 4 adverse effects were reported. Similarly, 12 reports (6 case series and 6 case reports) described the use of romiplostim in prolonged post-HSCT thrombocytopenia (in 17 patients with PIT and 32 patients with SFPR). Response with the increment of platelet count was described in 40 out of 49 patients (ORR, 82%). Among the responders, 10 patients had PIT (ORR for PIT, 59%) and 30 patients had SFPR (ORR for SFPR, 94%). Our data show that TPO-RAs have an overall favorable response rate for both PIT and SFPR with a reasonable safety profile. However, given the lack of control groups, study heterogeneity, and the potential publication bias, these results should be interpreted with caution.

Quality-of-Life Trajectories in Adolescent and Young Adult versus Older Adult Allogeneic Hematopoietic Cell Transplantation Recipients.

Hematopoietic cell transplantation (HCT) is physically and psychologically challenging, potentially exposing patients to quality-of-life (QoL) impairments. Adolescent and young adults (AYAs, aged 15 to 39 years) are a vulnerable cohort facing multiple hurdles due to dynamic changes in several aspects of their lives. The AYA population may be particularly prone to QoL issues during HCT. We hypothesized that due to the unique psychosocial challenges faced by AYAs, they would have an inferior quality of life. We studied QoL differences between AYA (aged 15 to 39 years) and older adult (aged 40 to 60 years) allogeneic HCT recipients before and after HCT. Additionally, we determined if pre-HCT QoL for AYA transplant recipients changed over time. QoL data were collected prospectively before and after transplant on 431 recipients aged 15 to 60 years from June 2003 through December 2017 using the Functional Assessment of Cancer Therapy-Bone Marrow Transplantation (FACT-BMT) questionnaire. Repeated-measures analysis of variance was used to assess differences among age groups. Pearson correlation (r) was used to determine if baseline QoL had improved after HCT from June 2003 through December 2017 in the AYA cohort. QoL did not differ among younger AYAs, older AYAs, or older adults at any time in the first year after allogeneic HCT. At 1 year post-HCT, total FACT-BMT score and all FACT-BMT domains except physical well-being improved from pre-HCT in all age groups. From 2003 to 2017, AYA allogeneic recipients experienced modest improvement in additional concerns (r = 0.26, P = .003), trial outcome index (r = 0.23, P = .008), and total FACT-BMT score (r = 0.19, P = .031), although no improvements were seen in physical, social, emotional, or functional well-being. Contrary to our hypothesis, we found that QoL in the AYA population is similar to that of older adults before and after HCT. Improvements in QoL of AYA allogeneic patients since 2003 were driven by the additional concerns domain, which addresses multiple psychosocial aspects such as vocation, hobbies, and acceptance of illness. Continued efforts to tailor treatment and support for AYA HCT recipients is critical to improving QoL outcomes.

The microbiome in pediatric oncology.

The human microbiome comprises a diverse set of microorganisms, which play a mostly cooperative role in processes such as metabolism and host defense. Next-generation genomic sequencing of bacterial nucleic acids now can contribute a much broader understanding of the diverse organisms composing the microbiome. Emerging evidence has suggested several roles of the microbiome in pediatric hematology/oncology, including susceptibility to infectious diseases, immune response to neoplasia, and contributions to the tumor microenvironment as well as changes to the microbiome from chemotherapy and antibiotics with unclear consequences. In this review, the authors have examined the evidence of the role of the microbiome in pediatric hematology/oncology, discussed how the microbiome may be modulated, and suggested key questions in need of further exploration.

Distance to treatment center is associated with survival in children and young adults with acute lymphoblastic leukemia.

BACKGROUND: Socioeconomic and demographic categories such as income, race, insurance status, and treatment center type are associated with outcomes in acute leukemia. This study was aimed at determining whether the distance to treatment center affects overall survival for children and young adults with acute leukemia. METHODS: The National Cancer Database was queried for patients 39 years old or younger who were diagnosed with acute myeloid leukemia (AML) or acute lymphoblastic leukemia (ALL). A backward elimination procedure was used to select final multivariate Cox models. RESULTS: In total, 12,301 patients with AML and 22,683 patients with ALL were analyzed. The ALL model included distance to treatment center, Charlson-Deyo score, age, race, insurance status, and community income level. US census definitions of urban and rural were not statistically significant, and no interaction was significant for included variables. Compared with distances > 50 miles, all other distances were associated with improved survival (hazard ratio [HR] for ≤10 miles, 0.91; P = .04; HR for >10 to ≤20 miles, 0.86; P = .004; HR for >20 to ≤50 miles, 0.87; P = .005). The final model for AML included the same variables as the ALL model except for distance to treatment center, which was not statistically significant. CONCLUSIONS: For children and young adults with ALL, distances > 50 miles are associated with inferior overall survival; however, no difference is seen for AML. Although it is unknown whether differences in survival for patients with ALL based on distance are driven by relapse or treatment-related mortality, increased attention to adherence, supportive care, and logistics for patients traveling long distances is warranted. LAY SUMMARY: For children and young adults with acute lymphoblastic leukemia, living more than 50 miles from the treatment center is associated with worse outcomes.

Continuous infusion chemotherapy, radiotherapy, and FDG-PET are feasible during extracorporeal membrane oxygenation.

Extracorporeal membrane oxygenation (ECMO) may be used in extreme circumstances for patients with a mediastinal mass and respiratory failure. We report on a young man with primary mediastinal B-cell lymphoma invading into the trachea, requiring a 40-day ECMO run who underwent fluorodeoxyglucose positron emission tomography (FDG-PET) imaging and treatment with concurrent mediastinal irradiation and continuous infusion chemotherapy while on this life-saving technology. This case illustrates that oncology patients may be managed by multidisciplinary teams for extended periods in extraordinary circumstances using multimodality therapies. Additionally, to our knowledge this is the first case to demonstrate the feasibility of FDG-PET imaging while on ECMO.

A Case of Congenital Anaplastic Large Cell Lymphoma in a Very Preterm Low-Birth Weight Neonate.

A premature infant male was born at 30 weeks' gestation with severe coagulopathy and thrombocytopenia. Over the first days of his life, the patient developed evidence of immune hyperactivation with adenopathy, hepatosplenomegaly, and elevated ferritin. Although the patient met diagnostic criteria for hemophagocytic lymphohistiocytosis (HLH), flow cytometric based assays were not consistent with primary HLH. A lymph node and bone marrow biopsy eventually revealed the presence of anaplastic lymphoma kinase+anaplastic large cell lymphoma. To our knowledge, this is the earliest presentation of a lymphoma, and expands the known timeframe of lymphomagenesis.

Ocular Graft-versus-Host Disease after Hematopoietic Cell Transplantation: Expert Review from the Late Effects and Quality of Life Working Committee of the Center for International Blood and Marrow Transplant Research and Transplant Complications Working Party of the European Society of Blood and Marrow Transplantation.

Ocular graft-versus-host disease (GVHD) occurs in more than one-half of patients who develop chronic GVHD after allogeneic hematopoietic cell transplantation (HCT), causing prolonged morbidity that affects activities of daily living and quality of life. Here we provide an expert review of ocular GVHD in a collaboration between transplantation physicians and ophthalmologists through the Late Effects and Quality of Life Working Committee of the Center for International Blood and Marrow Transplant Research and the Transplant Complications Working Party of the European Society of Blood and Marrow Transplantation. Recent updates in ocular GVHD regarding pathophysiology, preclinical models, risk factors, prevention, screening, diagnosis, response criteria, evaluation measures, and treatment are discussed. Ocular GVHD involves at least 3 biological processes: lacrimal gland dysfunction, meibomian gland dysfunction, and corneoconjunctival inflammation. Preclinical models have identified several novel pathogenic mechanisms, including the renin angiotensin system and endoplasmic reticulum stress signaling, which can be targeted by therapeutic agents. Numerous studies have identified reliable tests for establishing diagnosis and response assessment of ocular GVHD. The efficacy of systemic and topical treatment for ocular GVHD is summarized. It is important that all health professionals caring for HCT recipients have adequate knowledge of ocular GVHD to provide optimal care.

Effect of Conditioning Regimen Dose Reduction in Obese Patients Undergoing Autologous Hematopoietic Cell Transplantation.

Data are limited on whether to adjust high-dose chemotherapy before autologous hematopoietic cell transplant (autoHCT) in obese patients. This study explores the effects of dose adjustment on the outcomes of obese patients, defined as body mass index (BMI) ≥ 30 kg/m2. Dose adjustment was defined as a reduction in standard dosing ≥20%, based on ideal, reported dosing and actual weights. We included 2 groups of US patients who had received autoHCT between 2008 and 2014. Specifically, we included patients with multiple myeloma (MM, n = 1696) treated with high-dose melphalan and patients with Hodgkin or non-Hodgkin lymphomas (n = 781) who received carmustine, etoposide, cytarabine, and melphalan conditioning. Chemotherapy dose was adjusted in 1324 patients (78%) with MM and 608 patients (78%) with lymphoma. Age, sex, BMI, race, performance score, comorbidity index, and disease features (stage at diagnosis, disease status, and time to transplant) were similar between dose groups. In multivariate analyses for MM, adjusting for melphalan dose and for center effect had no impact on overall survival (P = .894) and treatment-related mortality (TRM) (P = .62), progression (P = .12), and progression-free survival (PFS; P = .178). In multivariate analyses for lymphoma, adjusting chemotherapy doses did not affect survival (P = .176), TRM (P = .802), relapse (P = .633), or PFS (P = .812). No center effect was observed in lymphoma. This study demonstrates that adjusting chemotherapy dose before autoHCT in obese patients with MM and lymphoma does not influence mortality. These results do not support adjusting chemotherapy dose in this population.

Non-Graft-versus-Host Disease Ocular Complications after Hematopoietic Cell Transplantation: Expert Review from the Late Effects and Quality of Life Working Committee of the Center for International Blood and Marrow Transplant Research and the Transplant Complications Working Party of the European Society for Blood and Marrow Transplantation.

Non-graft-versus-host disease (GVHD) ocular complications are generally uncommon after hematopoietic cell transplantation (HCT) but can cause prolonged morbidity affecting activities of daily living and quality of life. Here we provide an expert review of non-GVHD ocular complications in a collaboration between transplantation physicians and ophthalmologists through the Late Effects and Quality of Life Working Committee of the Center for International Blood and Marrow Transplant Research and the Transplant Complications Working Party of the European Society of Blood and Marrow Transplantation. Complications discussed in this review include cataracts, glaucoma, ocular infections, ocular involvement with malignancy, ischemic microvascular retinopathy, central retinal vein occlusion, retinal hemorrhage, retinal detachment and ocular toxicities associated with medications. We summarize the incidence, risk factors, screening, prevention, and treatment of individual complications and generate evidence-based recommendations. Baseline ocular evaluation before HCT should be considered in all patients who undergo HCT. Follow-up evaluations should be considered according to clinical signs and symptoms and risk factors. Better preventive strategies and treatments remain to be investigated for individual ocular complications after HCT. Both transplantation physicians and ophthalmologists should be knowledgeable about non-GVHD ocular complications and provide comprehensive collaborative team care.

Use of complement monoclonal antibody eculizumab in Shiga toxin producing Escherichia coli associated hemolytic uremic syndrome: A review of current evidence.

Complement activation plays an important role in the pathogenesis of atypical hemolytic uremic syndrome. Eculizumab is a monoclonal antibody that blocks complement activity and has been approved for use in the treatment of atypical hemolytic uremic syndrome (HUS). Less well appreciated is the role of complement in Shiga toxin-induced HUS (Shiga toxin producing Escherichia coli [STEC]-HUS). To a limited extent, eculizumab has been used off label in patients with severe STEC-HUS with neurological involvement. Through a systematic search of available databases, we identified 16 reports describing the use of eculizumab in STEC-HUS (eight case reports/series, seven retrospective studies, and one prospective cohort study). All studies described its use in severe STEC-HUS with neurological or multiorgan dysfunction; none were randomized or blinded. Four studies used the control groups. Although the overall quality of evidence is low, some published studies showed positive clinical improvement after treatment with eculizumab in severe STEC-HUS with progressive neurological involvement.