Hemolytic Uremic Syndrome Research Articles

Haemolytic uremic syndrome as a cause of chronic kidney disease stage 5 in children is in retreat: results from the Polish Registry of Kidney Replacement Therapy in children (2000-2023).

Haemolytic uremic syndrome (HUS) is a life-threatening disease with a historically poor prognosis in children receiving maintenance kidney replacement therapy (KRT). This study aimed to analyse the incidence and outcome of chronic kidney disease stage 5 (CKD5) due to Escherichia coli-HUS (STEC-HUS) and complement-mediated HUS (CM-HUS) in children, compared with controls with non-HUS CKD5 over the last 24years. The study included 1488 children undergoing KRT in Poland between 2000 and 2023. Thirty-nine patients with CM-HUS and 18 with STEC-HUS were identified and analysed for incidence, KRT modality and survival. The incidence rate of CKD5 was 0.09 cases/million age-related population (marp) for STEC-HUS and 0.23/marp for CM-HUS, while no new cases have been observed in recent years. CKD5 due to CM-HUS developed significantly earlier from initial HUS manifestation than in STEC-HUS (median 0.2 vs. 9.8years). CM-HUS was associated with younger age at initiation of KRT compared to STEC-HUS and non-HUS controls (median 6.0years vs. 10.9 and 10.9years), with higher risk of death (Hazard Ratio 1.92, 95% confidence interval 0.9-4.13) and worse 5-year kidney graft survival at 77%, 93% and 90%, respectively (p < 0.001). In recent years, both CM-HUS and STEC-HUS have become increasingly rare causes of CKD5 in children. CKD5 due to CM-HUS in the eculizumab era and due to STEC-HUS after improving supportive treatment is exceptional. Children on KRT due to STEC-HUS had a significantly better survival, shorter waiting time for kidney transplantation and better kidney graft survival compared to the CM-HUS group.

Treatment discontinuation in adults with atypical hemolytic uremic syndrome (aHUS): a qualitative study of international experts' perspectives with associated cost-consequence analysis.

Atypical hemolytic uremic syndrome (aHUS) is a rare, life-threatening thrombotic microangiopathy (TMA) related to congenital mutations impeding control of the alternative pathway of complement. Following approval of the complement C5 inhibitor eculizumab by the European Medicines Agency and the US Food and Drug Administration, initial guidelines suggested lifelong therapy. Yet, growing evidence indicates that discontinuation of eculizumab, or its long-acting form ravulizumab, is possible for many patients. This mixed-methods study sought to explore international experts' perspectives and experiences related to treatment duration in adult patients with aHUS, while also estimating the financial and potential health consequences of early discontinuation. Between January and December 2023, we conducted 10 qualitative interviews with experts in the treatment of aHUS, based upon which we constructed a quantitative decision tree, designed to estimate time on treatment and treatment- and disease-related adverse events. Thematic analysis of the interview data identified four main themes: (1) Concerns and prior experience; (2) High-risk vs. low-risk groups; (3) Patient preference and adherence; and (4) Funding for monitoring and re-treatment. Although most interviewees were in favour of considering treatment discontinuation for many patients (citing the high cost, burden, and potential side effects of lifelong treatment as key reasons), a prior negative experience of discontinuation seemed to make others more reluctant to stop. Deciding which patients required lifelong treatment and which not involved consideration of a wide range of factors, including patient- and system-related factors. Cost-consequence analysis demonstrated the financial savings associated with early treatment discontinuation at the expense of increased risk of recurrent TMA events. Close monitoring for these events had the potential to minimise any long-term injury, primarily renal, with an estimated one event per 100 patient years. For patients at high risk of TMA and with poor adherence to monitoring, rates of renal injury rose to three events per 100 patient years. aHUS treatment protocols are changing globally in response to new clinical evidence. Against this backdrop, our mixed-methods study provides compelling evidence on the complexity of factors influencing treatment discontinuation decisions in aHUS, as well as the financial and health consequences of early discontinuation.

Anti-Factor H Antibody Hemolytic Uremic Syndrome: A Disease in Need of “Make in India” Management

Anti-Factor H Antibody Hemolytic Uremic Syndrome: A Disease in Need of “Make in India” Management

A Unique Presentation of Atypical Hemolytic Uremic Syndrome With Unilateral Blindness and Ischemic Stroke: A Case Report

A Unique Presentation of Atypical Hemolytic Uremic Syndrome With Unilateral Blindness and Ischemic Stroke: A Case Report

Open-label, controlled, phase 2 clinical trial assessing the safety, efficacy, and pharmacokinetics of INM004 in pediatric patients with Shiga toxin-producing Escherichia coli-associated hemolytic uremic syndrome.

Shiga toxin-producing Escherichia coli-associated hemolytic uremic syndrome (STEC-HUS) is a severe condition mainly affecting children. It is one of the leading causes of acute kidney injury in the pediatric population. There is no established therapy for this disease. INM004 is an anti-Shiga toxin composed of equine polyclonal antibodies. This study is aimed at assessing the safety, pharmacokinetics, and efficacy of INM004 in pediatric patients with STEC-HUS. Phase 2, open-label clinical trial with an historical control arm. Patients in the treatment arm received two doses of INM004. The primary endpoints were the safety profile, pharmacokinetics, and efficacy (dialysis days) of INM004. Secondary endpoints included other kidney and extrarenal outcomes. Propensity score matching was used for efficacy comparisons between arms. Fifty-seven and 125 patients were enrolled in the treatment and control arm, respectively. After propensity score matching, 52 patients remained in each arm. INM004 was well-tolerated. Eight adverse events were considered possibly related, none of which were serious or severe. In the primary efficacy endpoint, patients of the treatment arm presented a non-statistically significant difference of two dialysis days. On secondary endpoints, non-statistically significant trends toward fewer patients needing dialysis and dialysis for more than 10days, and shorter time to glomerular filtration rate normalization, were observed favoring the treatment arm. INM004 showed an adequate safety profile. Efficacy non-statistically significant trends suggesting a beneficial effect in the amelioration of kidney injury were observed. These results encourage the conduction of a phase 3 study of INM004 in pediatric patients with STEC-HUS.

Prospective validation of initial eculizumab dosing in adults with atypical hemolytic uremic syndrome.

Prospective validation of initial eculizumab dosing in adults with atypical hemolytic uremic syndrome.

What, how, and why? - anti-EHEC phages and their application potential in medicine and food industry.

Enterohemorrhagic Escherichia coli (EHEC) are pathogens that, only in the United States, cause more than 250,000 foodborne infections a year. Since antibiotics or other antidiarrheal agents may increase the hemolytic-uremic syndrome (HUS) development risk, currently only supportive therapy, including hydration, is used. Therefore, many methods to fight EHEC bacteria focus on their use in food processing to prevent human infection. One of the proposed anti-EHEC agents is bacteriophages, known for their bactericidal effect, host specificity, and lack of cross-resistance with antibiotics. In this review article, we provide an overview of the characteristics like source of isolation, morphology, kinetics of life cycle, and treatment potential of over 130 bacteriophages able to infect EHEC strains. Based on the reviewed literature, we conclude that bacteriophages may play a highly significant role in regulating EHEC propagation. In addition, we also point out the phage features that should be taken into account not only when using bacteriophages but also when examining their properties. This may contribute to accelerating the pace of work on the preventive use of bacteriophages, which is extremely needed in the modern world of the food industry, but also stimulate interest in phages and accelerate regulatory work that would enable the use of bacteriophages also in medicine, to fight the drug-resistant strains.

Approaches to early detection of atypical hemolytic-uremic syndrome after childbirth

Introduction. Differentiating conditions accompanied by the development of thrombotic microangiopathy (TMA) in obstetrics is still rather challenging. Our present opinion is that the effect of childbirth on the TMA symptom regression is the key to differential diagnosis. If hemolysis and thrombocytopenia regress after childbirth, we can talk about HELLP syndrome. If not, we should think about atypical hemolytic uremic syndrome (aHUS). aHUS is an extremely rare disease characterized by TMA predominantly involving acute kidney injury. However, the diagnostic task can also be difficult due to possible overlapping one process with another: for example, HELLP syndrome can trigger aHUS, but which of the patients is more susceptible to this transformation is unclear.Aim. To identify clinical and laboratory criteria that can be used to early detect aHUS immediately after childbirth.Materials and methods. A total of 230 patients were enrolled in the study, of whom 71 women were diagnosed with aHUS, 124 patients with HELLP syndrome, and 35 patients without signs of TMA were enrolled in the control group. We assessed and compared the main clinical, anamnestic and laboratory findings.Results. Women with HELLP syndrome and aHUS were comparable in terms of age, frequency of operative delivery and gestational age at delivery, and adverse perinatal outcomes. Peak serum creatinine and LDH values after delivery were the most useful to early predict aHUS. Serum creatinine &gt; 142 μmol/L and LDH &gt; 1391 U/L were associated with the transformation of HELLP syndrome into aHUS.Conclusion. We concluded that standard laboratory data, most specifically peak serum creatinine and LDH, may be used to aid in the early diagnosis of aHUS.

Case Report of Dinutuximab-induced Atypical Hemolytic Uremic Syndrome.

Limited evidence exists describing the relationship between the development of atypical hemolytic uremic syndrome (aHUS) and the administration of dinutuximab. This case report describes a 20-year-old male with neuroblastoma who experienced aHUS post-dinutuximab administration. The patient presented with uncontrolled hypertension and renal dysfunction, ultimately receiving a definitive diagnosis of aHUS through a renal biopsy. The patient required complement-directed therapy with eculizmab and later transitioned to ravulizumab. This case further describes a sequential relationship between dinutuximab administration and aHUS development.

Gb3 trisaccharide-bearing exosomes as a novel neutralizer for Shiga toxin type 1

Shiga toxin types 1 (Stx1) and 2 (Stx2), produced by Shiga toxin-producing Escherichia coli (STEC) and Shigella dysenteriae, are key virulence factors responsible for severe foodborne diseases, such as hemorrhagic colitis and hemolytic uremic syndrome (HUS). The receptors for Stxs are Gb3 and P1 glycotope, which contain the Galα1→4Galβ epitope and are synthesized by human α1,4-galactosyltransferase (A4galt). Stx-related infections pose a global public health challenge, owing to the limited therapeutic options due to the restricted use of antibiotics. Therefore, there is an urgent need to develop novel therapeutic strategies. This study proposes an innovative strategy utilizing exosomes derived from CHO-Lec2 cells, which were modified with Functional-Spacer-Lipid (FSL) conjugates bearing the Gb3 carbohydrate epitope (exo-Gb3-FSL). Flow cytometry analysis confirmed the presence of Galα1→4Galβ disaccharides on exo-Gb3-FSL constructs, enabling them to bind Stx1. Moreover, using CHO-Lec2 cells verified the ability of exo-Gb3-FSL agents to bind Stx1 and protect these cells from Stx1-mediated cytotoxicity. For Stx1-treated CHO-Lec2 cells, increased cell survival was observed when using 25 μM exo-Gb3-FSL constructs, compared to control cells. These findings highlight the potential of exosome-based anti-Stx1 agents as promising alternatives to conventional therapies. This innovative strategy may provide novel directions for studies on Stx1 neutralization, offering a valuable strategy for the treatment of Stx-related diseases.

Genotypic analysis of Shiga toxin-producing Escherichia coli clonal complex 17 in England and Wales, 2014-2022.

Introduction. Shiga toxin-producing Escherichia coli (STEC) are zoonotic, gastrointestinal pathogens characterized by the presence of the Shiga toxin (stx) gene. Historically, STEC O157:H7 clonal complex (CC) 11 has been the most clinically significant serotype; however, recently there has been an increase in non-O157 STEC serotypes, including STEC O103:H2 belonging to CC17.Gap statement. STEC O103:H2 is an STEC serotype frequently isolated in England, although little is known about the epidemiology, clinical significance, associated public health burden or evolutionary context of this strain.Aim. Surveillance data and whole-genome sequencing data were analysed to determine the microbiological characteristics and public health burden of CC17, including the clinically significant serotype O103:H2, in England and Wales.Methodology. Isolates of E. coli belonging to CC17 (n=425) submitted to the Gastrointestinal Bacteria Reference Unit from 2014 to 2022 were whole genome sequenced, integrated with enhanced surveillance questionnaire data and analysed retrospectively.Results. Overall, diagnoses of CC17 infection increased every year since 2014. Most cases were female (58.5%), with the highest proportion of cases belonging to the 0-4 age group (n=83/424, 19.6%). Clinical presentation data identified diarrhoea (92.1%), abdominal pain (72.4%) and blood in stool (55.3%) as the most frequent symptoms, while 20.4% cases were admitted to hospital and 1.3% developed haemolytic uraemic syndrome. The five most common established serotypes were O103:H2 (64.5%), O123:H2 (11.1%), O151:H2 (6.6%), O71:H2 (3.3%) and O4:H2 (2.6%). The majority of CC17 isolates (78.6%) had the stx1a/eae virulence gene combination. Nine outbreak clusters of STEC infections that were mainly geographically dispersed and temporally related were identified and associated with foodborne transmission.Conclusions. Nationwide implementation of PCR to detect non-O157 STEC and improvements to algorithms for the follow-up of PCR-positive faecal specimens is recommended. Enhanced surveillance is necessary to assess the incidence of CC17 infection and overall burden of this CC within the UK population.

A novel multiplex and glycoprotein-based immunochromatographic serologic IgM test for the rapid diagnosis of Escherichia coli O157 and O145 causing bloody diarrhea and hemolytic uremic syndrome.

Shiga toxin-producing Escherichia coli (STEC) are the main etiological agents of hemolytic uremic syndrome (HUS). Good clinical management of STEC infections and HUS depends on early, rapid, and accurate diagnosis. Here, we have developed and evaluated the first multiplex and glycoprotein-based immunochromatographic test for the detection of IgM antibodies against the O-polysaccharide of the lipopolysaccharide of E. coli O157 and O145 in human serum samples. A retrospective study was carried out resulting in a diagnostic sensitivity of the E. coli O157/O145 LFIA (lateral flow immunoassay) of 97.1% and 98.9% for O157 and O145, respectively, and 97.9% for both serogroups. The diagnostic specificity was 98.7% for O157 and O145, and the overall specificity 97.4%. In samples obtained before 3 days after the onset of diarrhea, the detection percentage was 83%, increasing to 100% from 3 days onward. Finally, the association of bloody diarrhea (BD) or HUS cases to an STEC infection increased from 22.8% to 77.2% when stool culture and stx/Stx detection were combined with serology by LFIA. Our results demonstrate that the E. coli O157/O145 LFIA is a highly accurate and serospecific test for the early and rapid diagnosis of E. coli O157 and O145 infections in BD or HUS cases. This test allows the detection of specific IgM antibodies very early in the course of the infection, making it an ideal diagnostic tool to be implemented in pediatric emergencies and, thus, avoid delays in the application of the correct supportive or specific treatment and prevent complications associated with HUS.

Changing Epidemiology and Outcomes of Hemolytic Uremic Syndrome in Children: A Prospective National Cohort Study from the Polish Pediatric HUS Registry and the Polish Registry of Renal Replacement Therapy in Children.

Background/Objectives: Hemolytic uremic syndrome (HUS) is a known cause of acute kidney injury in children, but there are few recent reports on its epidemiology and outcome. We aimed to investigate trends in the incidence and the long-term outcomes of both Shiga toxin-producing Escherichia coli -HUS (STEC-HUS) and atypical HUS (aHUS) in Poland over the last 12 years (2012-2023), based on the Polish Pediatric HUS and Pediatric Renal Replacement Therapy (RRT) Registries. Methods: A total of 436 patients (301 with STEC-HUS and 135 with aHUS) were included. Results: The incidence of STEC-HUS increased during the observation period, with a mean of 3.9 cases per million age-related population (marp). The incidence of aHUS was relatively constant with a mean of 1.8/marp. The majority of patients fully recovered, although kidney sequelae were observed at 5-year follow-ups in 31% of children with STEC-HUS, 57% of aHUS subjects in the pre-eculizumab era, and 37% of aHUS subjects who had received eculizumab. The overall mortality rate was 2% for STEC-HUS and 3.7% for aHUS, with no deaths reported in children on eculizumab and mortality mainly attributed to neurological damage. A decreasing incidence of chronic kidney disease stage 5 (CKD5) due to HUS was observed. Conclusions: Despite an unchanging incidence of aHUS and an increasing incidence of STEC-HUS, the kidney outcomes of both diseases have improved significantly over the last 12 years. Mortality from HUS has dropped due to improved symptomatic treatment and the introduction of anti-C5 therapy. The development of CKD5 in childhood as a consequence of HUS has become exceptional.

Shiga Toxin-Producing E. coli and Hemolytic Uremic Syndrome: A Study of the 2022 Outbreak in Turkey

Shiga Toxin-Producing E. coli and Hemolytic Uremic Syndrome: A Study of the 2022 Outbreak in Turkey

Correlation between a 2-week change in platelet count and clinical outcomes after the initiation of ravulizumab treatment in adult patients with atypical hemolytic uremic syndrome: post-hoc analysis of the phase III trial

Correlation between a 2-week change in platelet count and clinical outcomes after the initiation of ravulizumab treatment in adult patients with atypical hemolytic uremic syndrome: post-hoc analysis of the phase III trial

Ultrasound analysis of different forms of hemolytic uremic syndrome in children.

Hemolytic uremic syndrome (HUS) is the most common cause of acute kidney injury in children. It is mainly caused by Shiga toxin-producing enterohemorrhagic Escherichia coli (EHEC; STEC-HUS) and is more rarely caused by uncontrolled complement activation (cHUS). Renal replacement therapy is frequently required and kidney function recovers in the majority of patients. Ultrasound (US) is the preferred imaging modality for the evaluation of any renal failure. The aim of this study is the evaluation of US diagnostics in both HUS types at disease onset and in the course of the disease. Clinical, laboratory, and US data from the digital patient records of children admitted as inpatients with a diagnosis of HUS were recruited for a monocentric, retrospective analysis. STEC-HUS and cHUS were diagnosed when, in addition to the laboratory constellation, EHEC infection and complement system activation were verified, respectively. US examinations were performed by pediatricians with certified pediatric US experience. In total, 30 children with STEC-HUS (13/25 male; median age of disease onset 2.9 years; most prevalent EHEC serotype was O157) and cHUS (2/5 male; median age of disease onset 5.4 years; 3/5 with proven pathogenic variation) were included. Renal replacement therapy proportions were comparable in the STEC-HUS and cHUS patients (64% vs. 60%). The resistance index (RI) was elevated at disease onset in the patients with STEC-HUS and cHUS (0.88 ± 0.10 vs. 0.77 ± 0.04, p = 0.13) and was similar in the STEC-HUS subcohorts divided based on dialysis requirement (yes: 0.86 ± 0.1; no: 0.88 ± 0.1; p = 0.74). Total kidney size at disease onset displayed a positive correlation with dialysis duration (R = 0.53, p = 0.02) and was elevated in both HUS types (177% ± 56 and 167% ± 53). It was significantly higher in the STEC-HUS subcohort which required dialysis (200.7% vs. 145%, p < .029), and a regressor kidney size threshold value of 141% was indicated in the receiver operating characteristic analysis. A classification model using both US parameters sequentially might be of clinical use for predicting the need for dialysis in patients with STEC-HUS. The US parameters normalized over time. The US parameters of RI and total kidney size are valuable for the assessment of HUS at disease onset and during therapy, and may be helpful in the assessment of whether dialysis is required in patients with STEC-HUS.

Beyond the Norm: Gastroenteritis-Induced Atypical Hemolytic Uremic Syndrome in the Absence of Complement Dysfunction

Beyond the Norm: Gastroenteritis-Induced Atypical Hemolytic Uremic Syndrome in the Absence of Complement Dysfunction

Scientometrics Analysis of Global Researches on Anemia

Background: Anemia is a condition in which the number of red blood cells or the hemoglobin concentration within them is lower than normal. This study aims to show the intellectual structure of knowledge regarding anemia and gives a comprehensive and up-to-date image of research in this area. Materials and Methods: This is a descriptive-analytical study with a scientometric approach. The PubMed database was searched for research publications indexed under "anemia" including 8484 records between 2011 and 2020. Data were analyzed using Co-word analysis, clustering methods, and strategic diagrams with the help of SPSS and Ucinet 6 software. Results: The keyword “Anemia Sickle Cell” and two pairs of frequently used keywords, namely “Anemia, Iron *Iron” were the most frequent in the research area. The results shaped the concepts of anemia in 9 clusters. The clusters "Hydroxyurea and sickle cell anemia", "Fetus transfusion", "Management of Thalassemia Major", "Hemolytic Uremic Syndrome", "Management and Control of Anemia", "Chronic Kidney Failure and Anemia", "Hematopoietic Stem Cell Transplantation" are topics that may be emerging or disappearing. The “Thalassemia and blood transfusion" are immature clusters. Conclusion: This study uses co-word networks that indicate important links between keywords of the research areas. Most research approaches are in the therapeutic aspects. Despite the importance of the effect of anemia on all levels of society, including economics, education, and other types of anemia, as well as its impact on learning and mental disorders, these subjects have not been given sufficient consideration.

Involvement of aquaporins in Shiga toxin-induced swelling and water transport dysfunction in human renal microvascular endothelial cells

One of the hallmarks of Shiga toxin-producing Escherichia coli-associated hemolytic uremic syndrome (STEC-HUS) is kidney damage. Our previous research demonstrated that Shiga toxin type 2 (Stx2a) decreases cell viability and induces swelling of human glomerular endothelial cells (HGEC). However, Stx2a can disrupt net water transport across HGEC monolayers without affecting cell viability. This work aimed to elucidate the possible mechanisms involved in the water transport disruption caused by Stx2a across HGEC monolayers. We investigated paracellular and transcellular water transfer across HGEC by analyzing the passage of FITC-Dextran and the hydrostatic pressure (Phydr) and measuring the osmotic pressure (Posm), respectively. Stx2a selectively affected the transcellular pathway without impacting the paracellular route. Furthermore, Stx2a cell swelling was prevented by pretreatment with aquaporin inhibitors tetraethylammonium chloride (TEA), Mercury (II) chloride (HgCl2) or TGN-020, suggesting aquaporin involvement in this process. Confocal microscopy revealed that Stx2a increased HGEC total volume, which TEA and TGN-020 counteracted. Additionally, we identified in HGEC not only the expression of aquaporin-1 (AQP1) but also the expression of aquaporin-4 (AQP4). Surprisingly, we observed a decrease in the expression of both AQPs after Stx2a exposure. Our findings suggest that Stx2a may induce water movement into HGEC via AQP1 and AQP4, increasing total cell volume. Subsequently, decreased AQP1 and AQP4 expression could inhibit transcellular water transfer, potentially as a protective mechanism against excessive water entry and cell lysis.

The Inhibitory Effects of a Factor B-Binding DNA Aptamer Family Supersede the Gain of Function of Factor B Variants Associated with Atypical Hemolytic Uremic Syndrome.

Aptamers are short, single-stranded oligonucleotides that selectively bind to target biomolecules. Although they generally exhibit good binding specificity, their affinities are often limited because of the relative lack of hydrophobic groups in nucleic acids. Chemically modified nucleotides incorporating hydrophobic structures into uracil have been synthesized to address this obstacle. Modified DNA aptamers containing such nonstandard nucleotides have been developed for >20 different complement proteins. These modified aptamers show increased affinity and enhanced serum stability and have potential value as therapeutic agents. We recently conducted a structure/function study on a family of modified DNA aptamers that bind specifically to complement Factor B (FB). This work revealed that these aptamers selectively inhibit the complement alternative pathway (AP) by preventing the formation of the AP complement component C3 (C3) proconvertase complex, C3bB. Certain patients with atypical hemolytic uremic syndrome express gain-of-function variants of FB that enhance the formation of the proconvertase complex and/or decrease the efficacy of endogenous regulators against the C3 convertases they form. To investigate whether these FB-binding aptamers could override the effects of disease-causing mutations in FB, we examined how they interacted with several FB variants, including D279G, F286L, K323E, and K350N, in various assays of complement function. We found that the inhibitory effect of the FB-binding aptamers superseded the gain-of-function mutations in FB, although the aptamers could not dissociate preformed C3 convertases. These findings suggest that FB-binding aptamers could be further developed as a potential treatment for certain atypical hemolytic uremic syndrome patients or those with other diseases characterized by excessive complement activity.