Interventions for haemolytic uraemic syndrome and thrombotic thrombocytopenic purpura

Interventions for preventing diarrhoea-associated haemolytic uraemic syndrome

BACKGROUND

Haemolytic uraemic syndrome (HUS) is a common cause of acquired kidney failure in children and rarely in adults. The most important risk factor for the development of HUS is a gastrointestinal infection by Shiga toxin-producing Escherichia coli (STEC). This is an update of the Cochrane review published in 2021 and addresses the interventions aimed at secondary prevention of HUS in patients with diarrhoea who are infected with bacteria that increase the risk of HUS.

OBJECTIVES

To assess the benefits and harms of interventions for secondary prevention of morbidity and death from diarrhoea-associated HUS in children and adults, compared to placebo or no treatment.

SEARCH METHODS

The Cochrane Kidney and Transplant Register of Studies was searched up to January 2025 by the Information Specialist using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Registry Platform (ICTRP) Search Portal and ClinicalTrials.gov.

SELECTION CRITERIA

Studies evaluating any intervention to prevent HUS following the development of high-risk diarrhoeal illness were included. These included interventions such as antibiotics, anti-Shiga toxin monoclonal antibodies, Shiga toxin binding protein (i.e. Synsorb Pk), bovine colostrum containing Shiga toxin antibodies, and aggressive hydration. The comparison groups included placebo and standard care. Only randomised controlled trials (RCTs) or quasi-RCTs were considered eligible for inclusion. The participants of the studies were children and adults with diarrhoeal illnesses due to STEC.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures as recommended by Cochrane. Summary estimates of effect were obtained using a random-effects model, and results were expressed as risk ratios (RR) and their 95% confidence intervals (CI) for dichotomous outcomes. The primary outcome of interest was the incidence of HUS; secondary outcomes included kidney failure, need for acute kidney replacement therapy (KRT), need for prolonged dialysis, all-cause death, adverse events, need for blood product transfusions and neurological complications. Confidence in the evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach.

MAIN RESULTS

For this 2025 update, no new studies were included. In the 2021 review, we identified four studies (536 participants) undertaken in three countries (Argentina, Canada, Germany) that investigated four different interventions, including antibiotics (trimethoprim-sulfamethoxazole), bovine colostrum containing Shiga toxin antibodies, Shiga toxin binding agent (Synsorb Pk: a silicon dioxide-based agent), and a monoclonal antibody against Shiga toxin (urtoxazumab). The overall risk of bias was unclear for selection, performance and detection bias and low for attrition, reporting and other sources of bias. It was uncertain if antibiotics (trimethoprim-sulfamethoxazole) reduced the incidence of HUS compared to no treatment (47 participants: RR 0.57, 95% CI 0.11 to 2.81; very low-certainty evidence). Adverse events relative to this review, need for KRT, neurological complications and death were not reported. There were no incidences of HUS in either the bovine colostrum group or the placebo group. It was uncertain if bovine colostrum caused more adverse events (27 participants: RR 0.92, 95% CI 0.42 to 2.03; very low-certainty evidence). The need for KRT, neurological complications and death were not reported. It is uncertain whether Synsorb Pk reduced the incidence of HUS compared to placebo (353 participants: RR 0.93, 95% CI 0.39 to 2.22; very low-certainty evidence). Adverse events relevant to this review, need for KRT, neurological complications and death were not reported. One study compared two doses of urtoxazumab (3.0 mg/kg and 1.0 mg/kg) to placebo. It is uncertain if either 3.0 mg/kg urtoxazumab (71 participants: RR 0.34, 95% CI 0.01 to 8.14) or 1.0 mg/kg urtoxazumab (74 participants: RR 0.95, 95% CI 0.06 to 14.59) reduced the incidence of HUS compared to placebo (very low-certainty evidence). Low-certainty evidence showed there may be little or no difference in the number of treatment-emergent adverse events with either 3.0 mg/kg urtoxazumab (71 participants: RR 1.00, 95% CI 0.84 to 1.18) or 1.0 mg/kg urtoxazumab (74 participants: RR 0.95, 95% CI 0.79 to 1.13) compared to placebo. It is uncertain if either dose of urtoxazumab increased the risk of neurological complications or death (very low-certainty evidence). The need for KRT was not reported.

AUTHORS' CONCLUSIONS

The included studies assessed antibiotics, bovine colostrum, Shiga toxin binding agent (Synsorb Pk) and monoclonal antibodies (Urtoxazumab) against Shiga toxin for secondary prevention of HUS in patients with diarrhoea due to STEC. However, no firm conclusions about the benefits or harms of these interventions can be drawn given the small number of included studies and the small sample sizes of those included studies. Additional studies, including larger multicentre studies, are needed to assess the benefits and harms of interventions to prevent the development of HUS in patients with diarrhoea due to STEC infection. No new studies were included in this 2025 update, and the results remain unchanged.

Ceftriaxone-Induced Thrombotic Thrombocytopenic Purpura Treated Successfully With Plasmapheresis and Eculizumab: A Rare Case Report

Thrombotic Thrombocytopenic Purpura (TTP) is a subtype of thrombotic microangiopathy (TMA) resulting in thrombocytopenia, anemia, fever, renal and neurological deficits. Although many drugs have been associated with drug-induced TTP, ceftriaxone has never been reported. Our case reports a patient who was started on ceftriaxone and developed TTP. Peripheral smear showed schistocytes and thrombocytopenia. Surprisingly, antibody formation against the metalloproteinase (ADAMTS13) levels were low-normal. The patient was treated with plasmapheresis and eczulimab, leading to platelet recovery and symptom resolution. TTP is a rare disorder and can be acquired or idiopathic. TTP can be diagnosed with normal ADAMTS13 as well. Further research is required to assess the mechanism by which ceftriaxone causes TTP. Physicians should consider the possibility of TTP in patients with similar presentations following ceftriaxone therapy and use it for timely diagnosis and treatment. Early diagnosis and treatment of ceftriaxone-induced TTP can prevent devastating consequences.

Interventions for preventing diarrhoea-associated haemolytic uraemic syndrome

BACKGROUND

Haemolytic uraemic syndrome (HUS) is a common cause of acquired kidney failure in children and rarely in adults. The most important risk factor for development of HUS is a gastrointestinal infection by Shiga toxin-producing Escherichia coli (STEC). This review addressed the interventions aimed at secondary prevention of HUS in patients with diarrhoea who were infected with a bacteria that increase the risk of HUS.

OBJECTIVES

Our objective was to evaluate evidence regarding secondary preventative strategies for HUS associated with STEC infections. In doing so, we sought to assess the effectiveness and safety of interventions as well as their potential to impact the morbidity and death associated with this condition.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Register of Studies up to 12 November 2020 through contact with the Information Specialist using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov.

SELECTION CRITERIA

Studies were considered based on the methods, participants, and research goals. Only randomised controlled trials were considered eligible for inclusion. The participants of the studies were paediatric and adult patients with diarrhoeal illnesses due to STEC. The primary outcome of interest was incidence of HUS.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures as recommended by Cochrane. Summary estimates of effect were obtained using a random-effects model, and results were expressed as risk ratios (RR) and their 95% confidence intervals (CI) for dichotomous outcomes. Confidence in the evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach.

MAIN RESULTS

We identified four studies (536 participants) for inclusion that investigated four different interventions including antibiotics (trimethoprim-sulfamethoxazole), anti-Shiga toxin antibody-containing bovine colostrum, Shiga toxin binding agent (Synsorb Pk: a silicon dioxide-based agent), and a monoclonal antibody against Shiga toxin (urtoxazumab). The overall risk of bias was unclear for selection, performance and detection bias and low for attrition, reporting and other sources of bias. It was uncertain if trimethoprim-sulfamethoxazole reduced the incidence of HUS compared to no treatment (47 participants: RR 0.57, 95% CI 0.11-2.81, very low certainty evidence). Adverse events relative to this review, need for acute dialysis, neurological complication and death were not reported. There were no incidences of HUS in either the bovine colostrum group or the placebo group. It was uncertain if bovine colostrum caused more adverse events (27 participants: RR 0.92, 95% CI 0.42 to 2.03; very low certainty evidence). The need for acute dialysis, neurological complications or death were not reported. It is uncertain whether Synsorb Pk reduces the incidence of HUS compared to placebo (353 participants: RR 0.93, 95% CI 0.39 to 2.22; very low certainty evidence). Adverse events relevant to this review, need for acute dialysis, neurological complications or death were not reported. One study compared two doses of urtoxazumab (3.0 mg/kg and 1.0 mg/kg) to placebo. It is uncertain if either 3.0 mg/kg urtoxazumab (71 participants: RR 0.34, 95% CI 0.01 to 8.14) or 1.0 mg/kg urtoxazumab (74 participants: RR 0.95, 95% CI 0.79 to 1.13) reduced the incidence of HUS compared to placebo (very low certainty evidence). Low certainty evidence showed there may be little or no difference in the number of treatment-emergent adverse events with either 3.0 mg/kg urtoxazumab (71 participants: RR 1.00, 95% CI 0.84 to 1.18) or 1.0 mg/kg urtoxazumab (74 participants: RR 0.95, 95% CI 0.79 to 1.13) compared to placebo. There were 25 serious adverse events reported in 18 patients: 10 in the placebo group, and 9 and 6 serious adverse events in the 1.0 mg/kg and 3.0 mg/kg urtoxazumab groups, respectively. It is unclear how many patients experienced these adverse events in each group, and how many patients experienced more than one event. It is uncertain if either dose of urtoxazumab increased the risk of neurological complications or death (very low certainty evidence). Need for acute dialysis was not reported.

AUTHORS' CONCLUSIONS

The included studies assessed antibiotics, bovine milk, and Shiga toxin inhibitor (Synsorb Pk) and monoclonal antibodies (Urtoxazumab) against Shiga toxin for secondary prevention of HUS in patients with diarrhoea due to STEC. However, no firm conclusions about the efficacy of these interventions can be drawn given the small number of included studies and the small sample sizes of those included studies. Additional studies, including larger multicentre studies, are needed to assess the efficacy of interventions to prevent development of HUS in patients with diarrhoea due to STEC infection.

Shiga Toxin-Associated Hemolytic Uremic Syndrome in Adults, France, 2009-2017

We conducted a retrospective study on hemolytic uremic syndrome caused by Shiga toxin–producing Escherichia coli (STEC) in 96 adults enrolled in the cohort of the National Reference Center for Thrombotic Microangiopathies network in France during 2009–2017. Most infections were caused by STEC strains not belonging to the O157 or O104 serogroups. Thirty (31.3%) patients had multiple risk factors for thrombotic microangiopathy. In total, 61 (63.5%) patients required dialysis, 50 (52.1%) had a serious neurologic complication, 34 (35.4%) required mechanical ventilation, and 19 (19.8%) died during hospitalization. We used multivariate analysis to determine that the greatest risk factors for death were underlying immunodeficiency (hazard ratio 3.54) and severe neurologic events (hazard ratio 3.40). According to multivariate analysis and propensity score-matching, eculizumab treatment was not associated with survival. We found that underlying conditions, especially immunodeficiency, are strongly associated with decreased survival in adults who have hemolytic uremic syndrome caused by STEC.

Interventions for atypical haemolytic uraemic syndrome

BACKGROUND

Atypical haemolytic uraemic syndrome (aHUS) is a rare disorder characterised by thrombocytopenia, microangiopathic haemolytic anaemia, and acute kidney injury. The condition is primarily caused by inherited or acquired dysregulation of complement regulatory proteins with ~40% of those affected aged < 18 years. Historically, kidney failure and death were common outcomes, however, improved understanding of the condition has led to discovery of novel therapies.

OBJECTIVES

To evaluate the benefits and harms of interventions for aHUS.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Register of Studies for randomised controlled studies (RCTs) up to 3 September 2020 using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov. MEDLINE(OVID) 1946 to 27 July 2020 and EMBASE (OVID) 1974 to 27 July 2020 were searched for non-RCTs.

SELECTION CRITERIA

All randomised and non-randomised clinical trials comparing an intervention with placebo, an intervention with supportive therapy, or two or more interventions for aHUS were included. Given the rare nature of the condition in question, prospective single-arm studies of any intervention for aHUS were also included.

DATA COLLECTION AND ANALYSIS

Two authors independently extracted pre-specified data from eligible studies and evaluated risk of bias using a newly developed tool based on existing Cochrane criteria. As statistical meta-analysis was not appropriate, qualitative analysis of data was then performed.

MAIN RESULTS

We included five single-arm studies, all of which evaluated terminal complement inhibition for the treatment of aHUS. Four studies evaluated the short-acting C5 inhibitor eculizumab and one study evaluated the longer-acting C5 inhibitor ravulizumab. All included studies within the review were of non-randomised, single-arm design. Thus, risk of bias is high, and it is challenging to draw firm conclusions from this low-quality evidence. One hundred patients were included within three primary studies evaluating eculizumab, with further data reported from 37 patients in a secondary study. Fifty-eight patients were included in the ravulizumab study. After 26 weeks of eculizumab therapy there were no deaths and a 70% reduction in the number of patients requiring dialysis. Complete thrombotic microangiopathic (TMA) response was observed in 60% of patients at 26 weeks and 65% at two years. After 26 weeks of ravulizumab therapy four patients had died (7%) and complete TMA response was observed in 54% of patients. Substantial improvements were seen in estimated glomerular filtration rate and health-related quality of life in both eculizumab and ravulizumab studies. Serious adverse events occurred in 42% of patients, and meningococcal infection occurred in two patients, both treated with eculizumab.

AUTHORS' CONCLUSIONS

When compared with historical data, terminal complement inhibition appears to offer favourable outcomes in patients with aHUS, based upon very low-quality evidence drawn from five single-arm studies. It is unlikely that an RCT will be conducted in aHUS and therefore careful consideration of future single-arm data as well as longer term follow-up data will be required to better understand treatment duration, adverse outcomes and risk of disease recurrence associated with terminal complement inhibition.

Plasma exchange and thrombotic microangiopathies: From pathophysiology to clinical practice

Thrombotic microangiopathy (TMA) brings together many diseases that have a commonality in the apparition of mechanical hemolysis with consuming thrombopenia. In all cases, these diseases can be life threatening, thereby justifying the implementation of treatment as an emergency. First-line treatment represents plasma exchange. This treatment has proven efficiency in improving the vital patient's and functional prognosis. However, the administration methods of plasma exchange can be redefined in light of the understanding of the pathophysiology of TMA. The aim of this review is to try to define, from pathophysiology, the place of plasma exchanges in the modern therapeutic arsenal of TMA.

Hemolytic uremic syndrome in a developing country: Consensus guidelines

BACKGROUND

Hemolytic uremic syndrome (HUS) is a leading cause of acute kidney injury in children. Although international guidelines emphasize comprehensive evaluation and treatment with eculizumab, access to diagnostic and therapeutic facilities is limited in most developing countries. The burden of Shiga toxin-associated HUS in India is unclear; school-going children show high prevalence of anti-factor H (FH) antibodies. The aim of the consensus meeting was to formulate guidelines for the diagnosis and management of HUS in children, specific to the needs of the country.

METHODS

Four workgroups performed literature review and graded research studies addressing (i) investigations, biopsy, genetics, and differential diagnosis; (ii) Shiga toxin, pneumococcal, and infection-associated HUS; (iii) atypical HUS; and (iv) complement blockade. Consensus statements developed by the workgroups were discussed during a consensus meeting in March 2017.

RESULTS

An algorithm for classification and evaluation was developed. The management of Shiga toxin-associated HUS is supportive; prompt plasma exchanges (PEX) is the chief therapy in patients with atypical HUS. Experts recommend that patients with anti-FH-associated HUS be managed with a combination of PEX and immunosuppressive medications. Indications for eculizumab include incomplete remission with plasma therapy, life-threatening features, complications of PEX or vascular access, inherited defects in complement regulation, and recurrence of HUS in allografts. Priorities for capacity building in regional and national laboratories are highlighted.

CONCLUSIONS

Limited diagnostic capabilities and lack of access to eculizumab prevent the implementation of international guidelines for HUS in most developing countries. We propose practice guidelines for India, which will perhaps be applicable to other developing countries.

Description of the Use of Plasma Exchange in Dogs With Cutaneous and Renal Glomerular Vasculopathy

Cutaneous and renal glomerular vasculopathy (CRGV) is a rare disease affecting dogs, with a recent apparent increase in prevalence since 2012 in the UK. This disease is characterized by a vasculopathy affecting small vessels of the kidney and skin, leading to thrombotic microangiopathy. The underlying etiology remains unknown although clinicopathological and histological findings resemble features of certain forms of thrombotic microangiopathy in people, for which plasma exchange (PEX) is considered an important component of therapy. The objective of the present study is to describe the use of PEX as adjunctive treatment in dogs diagnosed with CRGV. A retrospective review of dogs diagnosed with CRGV between 2014 and 2016 treated with PEX was performed. Clinical records were reviewed and data relating to signalment, diagnostic tests and management strategies were summarized. Information and complications relating to PEX were recorded. Six dogs were diagnosed with CRGV (n = 2 ante-mortem, n = 4 post-mortem) and underwent PEX as part of their therapy. All dogs had cutaneous lesions and were azotemic with oliguria or anuria. All dogs underwent at least one PEX cycle; one dog had a single cycle PEX, three dogs two cycles PEX, and two dogs had one cycle PEX and one cycle of prolonged intermittent renal replacement treatment. Complications seen during PEX therapy included hypothermia (n = 4), tachycardia (n = 2), hypotension (n = 2), and hypocalcemia (n = 6). Two dogs survived to discharge, the remaining four dogs were euthanized. The positive outcome in two dogs treated with PEX despite the reported high mortality rate once acute kidney injury with oliguria/anuria occurs does not confirm success of this treatment. However, survival in two dogs that were initially oligoanuric highlights that further consideration and evaluation of PEX for this patient group is warranted for this specific disease. Additional studies are urgently needed to identify the underlying etiology of CRGV before more targeted therapies can be developed. Based on our findings, further evaluation of the role of PEX in this specific disease are warranted.

Hemolytic uremic syndrome induced by infusion of oxaliplatin: A case report

Introduction

Oxaliplatin is a third-generation platinum compound with proven antitumor activity in the treatment of colorectal cancer. The occurrence of life-threating hemolitic uremic syndrome has been observed after oxaliplatin therapy. The kind of tumor and treatment modalities seem to influence the onset of hemolitic uremic syndrome.

Methods

The clinical course of the case is reviewed and compared with reports of other similar cases in the literature.

Results

We describe the development of hemolitic uremic syndrome as a result of prolonged oxaliplatin treatment of a colon cancer patient.

Conclusions

Although this rare event requires the concurrence of other unknown factors, it should be considered in a decision-making setting.

Thrombotic Microangiopathies (TTP, HUS, HELLP)

Thrombocytopenia, strictly defined as a platelet count less than 150,000, is common in the emergency department. Recognition, diagnostic investigation, and proper disposition of a thrombocytopenic patient are imperative. One group of disorders leading to thrombocytopenia is the thrombotic microangiopathies, hallmarked by platelet destruction. These thrombotic microangiopathies include thrombotic thrombocytopenic purpura (TTP), hemolytic uremic syndrome (HUS) and hemolysis, elevated liver enzyme levels, low platelet count (HELLP), which should be distinguished from similar disease processes such as immune thrombocytopenia (ITP), disseminated intravascular coagulation (DIC) and heparin induced thrombocytopenia (HIT). In this article, clinical presentations, pathophysiology, diagnostic workup, management plans, complications, and dispositions are addressed for this complex group of platelet disorders.

Systemic Lupus Erythematosus Presenting as Refractory Thrombotic Thrombocytopenic Purpura: A Diagnostic and Management Challenge. A Case Report and Concise Review of the Literature

BACKGROUND Thrombotic thrombocytopenic purpura (TTP) is one of the thrombotic microangiopathic (TMA) syndromes, caused by severely reduced activity of the vWF-cleaving protease ADAMTS13. Systemic lupus erythematosus (SLE), on the other hand, is an autoimmune disease that affects various organs in the body, including the hematopoietic system. SLE can present with TMA, and differentiating between SLE and TTP in those cases can be very challenging, particularly in patients with no prior history of SLE. Furthermore, an association between these 2 diseases has been described in the literature, with most of the TTP cases occurring after the diagnosis of SLE. In rare cases, TTP may precede the diagnosis of SLE or occur concurrently. CASE REPORT We present a case of a previously healthy 34-year-old female who presented with dizziness and flu-like symptoms and was found to have thrombocytopenia, hemolytic anemia, and schistocytes in the peripheral smear. She was subsequently diagnosed with TTP and started on plasmapheresis and high-dose steroids, but without a sustained response. A diagnosis of refractory TTP was made, and she was transferred to our facility for further management. Initially, the patient was started on rituximab, but her condition continued to deteriorate, with worsening thrombocytopenia. Later, she also fulfilled the Systemic Lupus International Collaborating Clinics (SLICC) criteria for diagnosis of SLE. Treatment of TTP in SLE patients is generally similar to that in the general population, but in refractory cases there are few reports in the literature that show the efficacy of cyclophosphamide. We started our patient on cyclophosphamide and noticed a sustained improvement in the platelet count in the following weeks. CONCLUSIONS Thrombotic thrombocytopenic purpura is a life-threatening hematological emergency which must be diagnosed and treated in a timely manner. Refractory cases of TTP have been described in the literature, but without clear evidence-based guidelines for its management, and is solely based on expert opinion and previous case reports. Further studies are needed to establish guidelines for its management. We present this case to highlight the role that cyclophosphamide might carry in those cases and to be a foundation for these future studies.

Antimicrobial resistance in Shiga toxin-producing Escherichia coli serogroups O157 and O26 isolated from human cases of diarrhoeal disease in England, 2015

OBJECTIVES

Shiga toxin-producing Escherichia coli (STEC) are zoonotic and transmission to humans occurs via contaminated food or contact with infected animals. In this study, WGS data were used to predict antimicrobial resistance (AMR) in STEC from symptomatic human cases to assess the extent of transmission of antibiotic-resistant E. coli from animals to humans.

METHODS

WGS data from 430 isolates of STEC were mapped to genes known to be associated with phenotypic AMR. Susceptibility testing was performed by a breakpoint method on all viable isolates exhibiting resistance to at least one antimicrobial.

RESULTS

327/396 (82.6%) of STEC O157 and 22/34 (64.7%) of STEC O26 lacked identifiable resistance genes and were predicted to be fully susceptible to 11 diverse classes of antimicrobials. For the remaining 81 isolates, 74 were phenotypically tested and there was concordance between WGS-predicted resistance and expression of phenotypic resistance. The most common resistance profile was ampicillin, streptomycin, trimethoprim/sulphonamide and tetracycline occurring in 25 (5.8%) isolates. Resistance to other antimicrobials, including resistance to chloramphenicol (2.1%), resistance to azithromycin (0.2%) and reduced susceptibility to ciprofloxacin (2.6%), was less frequent. Three isolates were identified as ESBL producers.

CONCLUSIONS

β-Lactams, trimethoprim/sulphonamides and tetracyclines account for the majority of therapeutic antimicrobials sold for veterinary use and this may be a risk factor for the presence of AMR in domestically acquired human clinical isolates of STEC. Isolates that were resistant to ampicillin, streptomycin, sulphonamide, tetracycline and azithromycin and had reduced susceptibility to ciprofloxacin were associated with cases who reported recent travel abroad.

Re-examination of 30-day survival and relapse rates in patients with thrombotic thrombocytopenic purpura-hemolytic uremic syndrome

BACKGROUND AND OBJECTIVES

Thrombotic thrombocytopenic purpura (TTP) and hemolytic uremic syndrome (HUS) are characterized by microangiopathic hemolytic anemia and thrombocytopenia. Interestingly, markedly different survival rates have been reported despite increases in survivability. We studied TTP-HUS 30-day mortality and relapse rates of patients who received TPE at our institution and compared them to published data.

PATIENTS AND METHODS

Retrospective study analyzed 30-day mortality and relapse rates attributed to TTP-HUS from 01/01/2008 to 12/31/2012 and compared them to comparable literature reporting mortality and survival. Studies describing other etiologies for TPE and different mortality time interval were excluded.

RESULTS

Fifty-nine patients were analyzed and all were initially treated with TPE and corticosteroids. Eleven patients were classified as not having TTP-HUS due to testing or clinical reassessment which ruled in other etiologies, and 18/59 patients had ADAMTS13 activity <10%. Of remaining patients, 36/48 (75%) were diagnosed as idiopathic and 12/48 (25%) as secondary TTP-HUS. Patients received a mean of 12 TPEs (range 1-42); 42/48 (87.5%) patients had ADAMTS13 activity measured; complete response obtained in 39/48 (81.2%) patients (platelet count >100 x 10(9)/L); partial response in 4/48 (8%); and 5/48 (10.4%) did not have increases in platelet counts (2/5 of these patients died within the study period). Forty percent of patients obtained platelet counts >150 x 10(9)/L. Overall 30-day mortality for our patient cohort was 6.7% (4/59). Comparison of our mortality rate to combined data of five published studies of 16% (92/571) showed a significant difference, p = 0.04. Our relapse rate was 18.6% (11/59) similar to previous reports.

CONCLUSIONS

Wide differences in mortality may be due to grouping of two distinct pathologic entities under TTP-HUS; and presence of confounding factors in the patient populations under study such as co-morbidities, promptness of TPE initiation, delay in diagnosis and therapeutic practice.

A diagnosis of haemolytic-uraemic syndrome blurred by alcohol abuse

A 60-year-old man with a history of alcohol abuse was admitted to the intensive care unit (ICU) for status epilepticus. At first, laboratory and imagery findings were almost normal, and the symptoms were attributed to severe alcohol withdrawal due to a history of gastroenteritis reported by his family. But, during the following days, haemolytic anaemia, thrombocytopenia, acute renal failure, and ischaemic and haemorrhagic lesions seen on a cerebral CT scan led to the diagnosis of haemolytic-uraemic syndrome (HUS). Despite these severe complications, the patient made a good recovery following ICU and plasma exchange with fresh frozen plasma (FFP), but cognitive deficit still existed after 1 month. It is important to know that neurological manifestations can precede typical biological and radiological signs in HUS, and to not be misled in the diagnosis process, especially when a more common differential diagnosis is possible.

Management of hemolytic uremic syndrome

Hemolytic uremic syndrome (HUS) is a disease characterized by hemolysis, thrombocytopenia, and acute kidney injury, although other organs may be involved. Most cases are due to infection with Shiga toxin-producing Escherichia coli (STEC). Early identification and initiation of best supportive care, with microbiological input to identify the pathogen, result in a favorable outcome in most patients. The remaining 10% of HUS cases are classed together as atypical HUS and have a diverse etiology. The majority are due to inherited or acquired abnormalities that lead to a failure to control complement activation. Atypical HUS occurring in other situations (for example, related to pregnancy or kidney transplantation) may also involve excessive complement activation. Plasma therapies can reverse defective complement control, and it is now possible to specifically target complement activation. This has led to improved outcomes in patients with atypical forms of HUS. We will review our current understanding of the pathogenesis of HUS and how this has led to advances in patient care.

Hemolytic uremic syndrome with simultaneous Shiga toxin producing Escherichia coli and complement abnormalities

Background

Hemolytic uremic syndrome is a common cause of acute kidney injury in children. In children, hemolytic uremic syndrome is most commonly associated with gasterointestinal infections caused by Shiga toxin-producing Escherichia coli or other enteric organisms. Although less common, atypical hemolytic uremic syndrome is triggered by multiple factors and portends a significantly worse prognosis with a high rate of recurrence.

Case presentation

Here we discuss the case of a 10 year old Caucasian male presenting with thrombocytopenia, anemia, and acute kidney injury.

Conclusions

This case highlights the clinical challenges in diagnosing and managing patients with hemolytic uremic syndrome. Because of similarity in symptoms, differentiating Shiga toxin-producing Escherichia coli associated hemolytic uremic syndrome and atypical hemolytic uremic syndrome can be challenging. However, because of the increased morbidity and mortality of atypical hemolytic uremic syndrome, early detection and initiation of therapy are critical. Providers must have a heightened suspicion in order to initiate supportive care or disease directed therapy in the case of atypical hemolytic uremic syndrome.

Cryosupernatant and Immunosuppression as Effective Alternative Therapies for TTP in Three Pediatric SLE Patients

Thrombotic thrombocytopenic purpura (TTP) and systemic lupus erythematosus (SLE) very rarely present simultaneously and pose a diagnostic and therapeutic dilemma to the physician. Prompt diagnosis and management with plasma exchange and immunosuppression is life-saving. To describe the effectiveness of cryosupernatant and steroids in pediatric SLE with TTP. We describe three children aged 12-14 years with SLE who were diagnosed with TTP based on fever, CNS manifestations, ANA, anti-dsDNA, anti-sm positivity, hypocomplementemia, and microangiopathic anemia with thrombocytopenia. All three children were managed with cryosupernatant and steroids without plasmapheresis. All children improved with cryosupernatant and steroids. All attained remission within 10 days. They were doing well at last follow up without relapse or flare. Cryosupernatant and steroids may be an effective therapy for Thrombotic thrombocytopenic purpura with systemic lupus erythematosus.

Severe Leptospira interrogans serovar Icterohaemorrhagiae infection with hepato-renal-pulmonary involvement treated with corticosteroids

Key Clinical Message

The traditional concept of immediate antibiotic treatment in suspected leptospirosis seems to be especially important for patients up to day 4 of clinical illness. As immune mechanisms probably play a crucial role in advanced leptospirosis with presumed pulmonary hemorrhages, patients might benefit from corticosteroids or other immunosuppressive agents beside antibiotics.

Taking bacteriophage therapy seriously: a moral argument

The excessive and improper use of antibiotics has led to an increasing incidence of bacterial resistance. In Europe the yearly number of infections caused by multidrug resistant bacteria is more than 400.000, each year resulting in 25.000 attributable deaths. Few new antibiotics are in the pipeline of the pharmaceutical industry. Early in the 20th century, bacteriophages were described as entities that can control bacterial populations. Although bacteriophage therapy was developed and practiced in Europe and the former Soviet republics, the use of bacteriophages in clinical setting was neglected in Western Europe since the introduction of traditional antibiotics. Given the worldwide antibiotic crisis there is now a growing interest in making bacteriophage therapy available for use in modern western medicine. Despite the growing interest, access to bacteriophage therapy remains highly problematic. In this paper, we argue that the current state of affairs is morally unacceptable and that all stakeholders (pharmaceutical industry, competent authorities, lawmakers, regulators, and politicians) have the moral duty and the shared responsibility towards making bacteriophage therapy urgently available for all patients in need.

Outbreak of Escherichia coli O104:H4 haemolytic uraemic syndrome in France: outcome with eculizumab

Background

An outbreak of haemolytic uraemic syndrome (HUS) due to Shiga toxin-secreting Escherichia coli (STEC) O104:H4 from contaminated fenugreek sprouts occurred in June 2011 near Bordeaux, France. In the context of this outbreak, all patients were treated with the monoclonal anti-C5 antibody, eculizumab.

Methods

The diagnosis of HUS was made based on haemolytic anaemia, low platelet count and acute kidney injury. Data were obtained from initial gastrointestinal symptoms to the end of follow-up 10 weeks after the start of eculizumab.

Results

Among 24 cases of STEC gastroenteritis, HUS developed in nine patients (eight adults and one child), 6 (median; range 3–12) days after digestive symptoms begun. The median (range) highest or lowest biological values were platelet count 26 (range 14–93) G/L; haemoglobin 6.6 (range 5–10.7) g/dL; LDH 1520 (range 510–2568) IU/L; creatinine 152 (range 48–797) µmol/L. All patients had extra-renal complications (liver 9, pancreas 5, brain 3 and heart 3). Two patients were dialysed, and one was ventilated. After failure of plasma exchange to increase platelets in the first three patients, eculizumab was administered in all nine patients, 0–4 days after HUS diagnosis (median 1 day). One patient with very severe neurological HUS received immunoadsorption. Outcome was favourable in all patients, with rapid normalization of haemoglobin, platelets, LDH levels, renal function and neurological improvement. There were no deaths and no serious adverse events related to eculizumab.

Conclusions

Early treatment of O104:H4 STEC-HUS by eculizumab was associated with a rapid and efficient recovery. Controlled prospective evaluation of eculizumab in STEC-HUS is warranted.

Management of pregnancy-associated thrombotic thrombocytopenia purpura

Thrombotic thrombocytopenia purpura (TTP) is an infrequent but serious disease. Pregnancy is a known risk factor for presentation or relapse of TTP. Difficulties in differentiating TTP from preeclampsia/HELLP (hemolysis, elevated liver enzymes and low platelets) syndrome, and current treatment recommendations are discussed in this case report. A woman with previously treated and stable TTP had a relapse at 36 weeks' gestation. Careful surveillance led to an early diagnosis. Severe disease in the peripartum period was treated successfully with cryosupernatant plasma-based plasmapheresis and platelet transfusion, with good maternal and neonatal outcomes. Cryosupernatant plasma is a viable alternative to fresh frozen plasma for plasmapheresis for TTP and may offer some therapeutic and logistical advantages. Platelet transfusion can be undertaken safely if needed to prevent or treat significant hemorrhage.

Lessons Learned From Outbreaks of Shiga Toxin Producing Escherichia coli

In 2011, a large outbreak caused by a Shiga toxin producing E. coli (STEC) occurred in Northern Germany, with a satellite outbreak in Western France, including the highest number of hemolytic uremic syndrome (HUS) cases ever encountered during a STEC outbreak. The outbreak strain was characterized as an enteroaggregative E. coli of serotype O104:H4 expressing a phage-encoded Shiga toxin 2. The majority of STEC infections and HUS cases were observed in adults, with a preponderance of the female gender. The outbreak imposed huge challenges on clinicians, microbiologists, and epidemiologists but also provided important new insight for the understanding of STEC infection. Thus, novel therapeutic strategies in the treatment of HUS in adults and for decolonization of long-term STEC carriers were evaluated. This review highlights the unusual features of the recent O104:H4 outbreak and focuses on emerging new strategies in diagnostics and treatment of acute STEC-related disease, as well as STEC long-term carriage.

Microbes without frontiers: severe haemolytic-uraemic syndrome due to E coli O104:H4

Antibiotic use in infection with Shiga-toxin-producing strains of Escherichia coli (E coli) is thought to increase the risk of developing haemolytic-uraemic syndrome (HUS). One paediatric study concluded that E coli O157:H7-infected patients who had received antibiotic therapy were 17 times more likely to progress to HUS than those who had not. Quinolones are among those incriminated. In vitro experiments suggest toxin induction of 80-fold with ciprofloxacin and E coli O104:H4. We report here the case of a 44-year-old man returning from Hamburg who presented with a 5 day history of bloody diarrhoea which had worsened after starting ciprofloxacin. A severe illness of overlapping HUS and thrombotic thrombocytopaenic purpura (TTP) ensued, with neurological complications requiring ventilation and intensive care admission. Stool sample eventually confirmed E coli O104:H4. Although the patient made a good recovery following treatment with haemofiltration and plasma exchange with fresh frozen plasma (FFP), ciprofloxacin may have exacerbated his clinical course.

Selection and characterization of a candidate therapeutic bacteriophage that lyses the Escherichia coli O104:H4 strain from the 2011 outbreak in Germany

In 2011, a novel strain of O104:H4 Escherichia coli caused a serious outbreak of foodborne hemolytic uremic syndrome and bloody diarrhea in Germany. Antibiotics were of questionable use and 54 deaths occurred. Candidate therapeutic bacteriophages that efficiently lyse the E. coli O104:H4 outbreak strain could be selected rather easily from a phage bank or isolated from the environment. It is argued that phage therapy should be more considered as a potential armament against the growing threat of (resistant) bacterial infections.

Shigatoxin-associated hemolytic uremic syndrome: current molecular mechanisms and future therapies

Hemolytic uremic syndrome is the leading cause of acute kidney injury in childhood. Ninety percent of cases are secondary to gastrointestinal infection with shigatoxin-producing bacteria. In this review, we discuss the molecular mechanisms of shigatoxin leading to hemolytic uremic syndrome and the emerging role of the complement system and vascular endothelial growth factor in its pathogenesis. We also review the evidence for treatment options to date, in particular antibiotics, plasma exchange, and immunoadsorption, and link this to the molecular pathology. Finally, we discuss future avenues of treatment, including shigatoxin-binding agents and complement inhibitors, such as eculizumab.

Shiga toxin-producing Escherichia coli O104:H4: a new challenge for microbiology

In 2011, Germany experienced the largest outbreak with a Shiga toxin-producing Escherichia coli (STEC) strain ever recorded. A series of environmental and trace-back and trace-forward investigations linked sprout consumption with the disease, but fecal-oral transmission was also documented. The genome sequences of the pathogen revealed a clonal outbreak with enteroaggregative E. coli (EAEC). Some EAEC virulence factors are carried on the virulence plasmid pAA. From an unknown source, the epidemic strains acquired a lambdoid prophage carrying the gene for the Shiga toxin. The resulting strains therefore possess two different mobile elements, a phage and a plasmid, contributing essential virulence genes. Shiga toxin is released by decaying bacteria in the gut, migrates through the intestinal barrier, and is transported via the blood to target organs, like the kidney. In a mouse model, probiotic bifidobacteria interfered with transport of the toxin through the gut mucosa. Researchers explored bacteriophages, bacteriocins, and low-molecular-weight inhibitors against STEC. Randomized controlled clinical trials of enterohemorrhagic E. coli (EHEC)-associated hemolytic uremic syndrome (HUS) patients found none of the interventions superior to supportive therapy alone. Antibodies against one subtype of Shiga toxin protected pigs against fatal neurological infection, while treatment with a toxin receptor decoy showed no effect in a clinical trial. Likewise, a monoclonal antibody directed against a complement protein led to mixed results. Plasma exchange and IgG immunoadsoprtion ameliorated the condition in small uncontrolled trials. The epidemic O104:H4 strains were resistant to all penicillins and cephalosporins but susceptible to carbapenems, which were recommended for treatment.

E. coli O104:H4 outbreak and haemolytic-uraemic syndrome

BACKGROUND

The first cases of the European epidemic of Shiga toxin-producing Escherichia coli O104:H4 (STEC-O104:H4) infection were reported in Germany in April 2011.

OBJECTIVES

To characterize the 2011 STEC-O104:H4 outbreak and its management. A literature review is made to assess the state of the art in STEC-haemolytic-uraemic syndrome (HUS) epidemiology, pathogenesis, management and prognosis, focusing on critically ill adults.

METHODS

References were obtained from the European Center for Disease Control and World Health Organization epidemiological updates, in addition to a PubMed search covering the period from 1980 to August 2011, including all published work on STEC-014:H4 and reviews on HUS management and prognosis.

RESULTS

The epidemic originated from a bean and seed sprouts farm in Lower Saxony, and was caused by the O104:H4 strain - a highly antibiotic resistant, hybrid enteroaggregative - Shiga toxin producing E. coli strain (STEC). The infection was characterized by increased HUS (25%) and a higher mortality rate. STEC enteritis and HUS are associated with significant mortality and morbidity, especially amongst patients with severe renal and neurological disorders. Management should center on prompt kidney protection by maintaining adequate renal perfusion, in addition to avoiding diuretics and nephrotoxic agents.

CONCLUSIONS

The published studies regarding antibiotic treatment lack good quality evidence. However, recent data suggest a potential modulating effect that explains the conflicting data but moreover suggests that azithromycin might be of use. Neutralizing monoclonal antibodies are a promising new therapy for STEC-HUS, with currently ongoing studies. Other treatments have not been shown to be superior to supportive therapy alone.

Microparticle generation and leucocyte death in Shiga toxin-mediated HUS

BACKGROUND

Shiga toxin-induced haemolytic uraemic syndrome (STEC-HUS) is an acute multisystem disorder characterized by renal failure, neurological dysfunction, haemolysis and intravascular thrombosis. Circulating microparticles originating from a number of cell types including thrombocytes and leucocytes are elevated in paediatric patients. In vitro data also suggest modification of leucocyte death by Shiga toxin. Here, we investigated microparticle generation and leucocyte cell death in vivo in adult STEC-HUS patients during acute disease and recovery.

METHODS

Multi-colour flow cytometry and immunofluorescence were used to assess microparticle concentration and provenience thrombocyte microparticle seeding to leucocytes and leucocyte cell death in adult STEC-HUS patients treated at a tertiary care centre during the STEC-HUS outbreak in Germany in 2011.

RESULTS

Plasma microparticle concentrations of both platelet and leucocyte origin were elevated during acute STEC-HUS. Platelet microparticles (MP) were detected on a high proportion of monocytes and granulocytes. Among therapeutic interventions, plasma exchange reduced platelet marker expression on leucocytes, inhibition of complement had only moderate impact on the number of circulating MP and did not alter platelet microparticle binding to leucocytes. Numbers of apoptotic and necrotic monocytes and granulocytes were significantly increased in patients with STEC-HUS compared to healthy controls. Complement inhibition significantly increased the number of circulating apoptotic cells. Monocyte apoptosis on admission was significantly higher in patients subsequently assigned to plasma exchange or admitted to the intensive care unit.

CONCLUSIONS

In STEC-HUS, elevated numbers of circulating MP and dead leucocytes were detected. Monocyte and granulocyte deaths are novel markers of acute STEC-HUS that may actively contribute to tissue destruction by liberation of pro-inflammatory enzymes and cytokines.

Management of an acute outbreak of diarrhoea-associated haemolytic uraemic syndrome with early plasma exchange in adults from southern Denmark: an observational study

BACKGROUND

Diarrhoea-associated haemolytic uraemic syndrome in adults is a life-threatening, but rare multisystem disorder that is characterised by acute haemolytic anaemia, thrombocytopenia, and renal insufficiency. We aimed to assess the success of management of this disorder with plasma exchange therapy.

METHODS

Patients diagnosed with diarrhoea-associated haemolytic uraemic syndrome in southern Denmark were treated with daily plasma exchange by centrifugation and substitution with fresh frozen plasma. Stool culture and serological testing was done to identify the cause of disease, and the success of management with plasma exchange therapy was assessed from change in platelet count, glomerular filtration rate, and lactate dehydrogenase.

FINDINGS

During May 25-28, 2011, five patients with a median age of 62 years (range 44-70) presented with diarrhoea-associated haemolytic uraemic syndrome, which was caused by an unusual Shiga-toxin-producing Escherichia coli serotype O104:H4. Strains of E coli showed a high resistance to third-generation cephalosporins because the strains had extended-spectrum β lactamases. After plasma exchange, median platelet count and glomerular filtration rate increased, median lactate dehydrogenase concentration decreased, and neurological status improved. The time interval from onset of bloody diarrhoea to start of plasma exchange had an inverse correlation with reduction of lactate dehydrogenase concentrations by plasma exchange (p=0.02). All patients were discharged with normal neurological status at 7 days (range 5-8) after starting plasma exchange.

INTERPRETATION

Early plasma exchange might ameliorate the course of diarrhoea-associated haemolytic uraemic syndrome in adults. However, this finding should be verified in randomised controlled trials

FUNDING

None.

Microangiopathic disorders in pregnancy

Microangiopathic disorders present with thrombocytopenia, hemolytic anemia, and multiorgan damage. In pregnancy, these disorders present a challenge both diagnostically and therapeutically, with widely overlapping clinical scenarios and disparate treatments. Although rare, a clear understanding of these diseases is important because devastating maternal and fetal outcomes may ensue if there is misdiagnosis and improper treatment. Microangiopathic disorders presenting in pregnancy are thus best assessed and treated by both obstetric and hematology teams. As a better understanding of the pathophysiology underlying each of the disease processes is gained, new diagnostic testing and therapies will be available, which will lead to improved outcomes.

Advances in our understanding of the pathogenesis of glomerular thrombotic microangiopathy

Glomerular thrombotic microangiopathy is a hallmark feature of haemolytic uraemic syndrome, the leading cause of acute renal failure in childhood. This paper is a review of the different mechanistic pathways that lead to this histological picture in the kidney. It will focus on atypical HUS and complement dysregulation, but will also highlight some other recent advances in our understanding of this condition, including the potential role of the molecule vascular endothelial growth factor-A (VEGF-A).

Escherichia coli O157

Escherichia coli O157 is an uncommon but serious cause of gastroenteritis. This bacterium is noteworthy because a few, but significant, number of infected people develop the haemolytic uraemic syndrome, which is the most frequent cause of acute renal failure in children in the Americas and Europe. Many infections of E coli O157 could be prevented by the more effective application of evidence-based methods, which is especially important because once an infection has been established, no therapeutic interventions are available to lessen the risk of the development of the haemolytic uraemic syndrome. This Review takes into account the evolution and geographical distibution of E coli O157 (and its close pathogenic relatives); the many and varied routes of transmission from its major natural hosts, ruminant farm animals; and other aspects of its epidemiology, its virulence factors, the diagnosis and management of infection and their complications, the repercussions of infection including costs, and prevention.

Recent advances in diagnosis and treatment of atypical haemolytic uraemic syndrome

New understanding of the underlying pathology of the thrombotic microangiopathies has resulted in guidelines for the investigation and management of atypical haemolytic uraemic syndrome in children and adults and the prospect of new therapies, which are in clinical trial. Patients should be investigated for defects in complement pathways and a trial of plasma exchange is indicated.

Interventions for haemolytic uraemic syndrome and thrombotic thrombocytopenic purpura

BACKGROUND

Haemolytic uraemic syndrome (HUS) and thrombotic thrombocytopenic purpura (TTP) are related conditions with similar clinical features of variable severity. Survival of patients with HUS and TTP has improved greatly over the past two decades with improved supportive care for patients with HUS and by the use of plasma exchange (PE) with fresh frozen plasma (FFP) for patients with TTP. Separate pathogenesis of these two disorders has become more evident, but management overlaps.

OBJECTIVES

To evaluate the benefits and harms of different interventions for HUS and TTP separately, in patients of all ages.

SEARCH STRATEGY

We searched MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials (CENTRAL), conference proceedings, reference lists of articles and text books and contact with investigators were used to identify relevant studies.

SELECTION CRITERIA

Randomised controlled trials (RCTs) evaluating any interventions for HUS or TTP in patients of all ages.

DATA COLLECTION AND ANALYSIS

Three authors independently extracted data and evaluated study reporting quality using standard Cochrane criteria. Analysis was undertaken using a random effects model and results expressed as risk ratio (RR) and 95% confidence intervals (CI).

MAIN RESULTS

For TTP, we found six RCTs (331 participants) evaluating PE with FFP as the control. Interventions tested included antiplatelet therapy (APT) plus PE with FFP, FFP transfusion and PE with cryosupernatant plasma (CSP). Two studies compared plasma infusion (PI) to PE with FFP and showed a significant increase in failure of remission at two weeks (RR 1.48, 95% 1.12 to 1.96) and all-cause mortality (RR 1.91, 95% 1.09 to 3.33) in the PI group. Seven RCTs were undertaken in children with HUS. None of the assessed interventions used (FFP transfusion, heparin with or without urokinase or dipyridamole, shiga toxin binding protein and steroids) were superior to supportive therapy alone, for all-cause mortality, neurological/extrarenal events, renal biopsy changes, proteinuria or hypertension at the last follow-up visit. Bleeding was significantly higher in those receiving anticoagulation therapy compared to supportive therapy alone (RR 25.89, 95% CI 3.67 to 182.83).

AUTHORS' CONCLUSIONS

PE with FFP is still the most effective treatment available for TTP. For patients with HUS, supportive therapy including dialysis is still the most effective treatment. All studies in HUS have been conducted in the diarrhoeal form of the disease. There were no RCTs evaluating the effectiveness of any interventions on patients with atypical HUS who have a more chronic and relapsing course.