Cardiac failure in hemolytic uremic syndrome and rescue with extracorporeal life support

Extracorporeal Membrane Oxygenation and Hemolytic Uremic Syndrome in Children: Outcome Review of a Multicenter National Database

Hemolytic uremic syndrome (HUS) is a triad of hemolytic anemia, thrombocytopenia, and acute renal failure. In critically ill children with HUS, extrarenal manifestations may require intensive care unit admission and extracorporeal membrane oxygenation (ECMO) support. Outcomes specific to HUS and ECMO in children have not been well investigated. The primary aim of this project was to query a multicenter database to identify risk factors associated with mortality in HUS patients supported on ECMO. A secondary aim was to identify factors associated with ECMO utilization in children with HUS. Utilizing the Pediatric Health Information System database (January 2004 and September 2018), this retrospective, multicenter cohort study identified the index HUS hospitalization among children aged 0 to 18 years. Univariate analysis was used to compare demographics, clinical characteristics, and procedures to identify risk factors associated with adverse outcomes. Among 4,144 subjects, 37 were supported on ECMO. Survival for those on ECMO support was 54%. Among nonsurvivors, 59% of deaths occurred within 14 days of hospitalization. The mean hospital LOS was 15.9 days in nonsurvivors versus 53.9 days for survivors (p < 0.001). When comparing subjects supported on ECMO to those who were not, patients with ECMO support had statistically longer hospital LOS and higher rates of extrarenal involvement (p < 0.001). This study found a mortality rate of 46% among HUS patients requiring ECMO. The investigated clinical risk factors were not associated with mortality among the ECMO population. The study identifies risk factors associated with ECMO utilization in children with HUS.

Cardiac Manifestation among Children with Hemolytic Uremic Syndrome

OBJECTIVE

The primary objectives of the study were to describe the association between cardiac manifestations and in-hospital mortality among children with hemolytic uremic syndrome.

STUDY DESIGN

Using the Pediatric Health Information System database, this retrospective, multicenter, cohort study identified the first hemolytic uremic syndrome-related inpatient visit among children ≤18 years (years 2004-2018). The frequency of selected cardiac manifestations and mortality rates were calculated. Multivariate analysis identified the association of specific cardiac manifestations and the risk of in-hospital mortality.

RESULTS

Among 3915 patients in the analysis, 238 (6.1%) had cardiac manifestations. A majority of patients (82.8%; n = 197) had 1 cardiac condition and 17.2% (n = 41) had ≥2 cardiac conditions. The most common cardiac conditions was pericardial disease (n = 102), followed by congestive heart failure (n = 46) and cardiomyopathy/myocarditis (n = 34). The percent mortality for patients with 0, 1, or ≥2 cardiac conditions was 2.1%, 17.3%, and 19.5%, respectively. Patients with any cardiac condition had an increased odds of mortality (OR, 9.74; P = .0001). In additional models, the presence of ≥2 cardiac conditions (OR, 9.90; P < .001), cardiac arrest (OR, 38.25; P < .001), or extracorporeal membrane oxygenation deployment (OR, 11.61; P < .001) were associated with increased risk of in-hospital mortality.

CONCLUSIONS

This study identified differences in in-hospital mortality based on the type of cardiac manifestations, with increased risk observed for patients with multiple cardiac involvement, cardiac arrest, and extracorporeal membrane oxygenation deployments.

Extra-corporeal membrane oxygenation and Eculizumab: Atypical treatments for typical haemolytic uraemic syndrome

A 19-year-old female with no medical history presented with bloody diarrhoea. Investigations revealed an acute kidney injury, thrombocytopenia and microangiopathic haemolysis. A diagnosis of haemolytic uraemic syndrome secondary to Shiga toxin-producing Escherichia coli 055 was confirmed and supportive therapy commenced in the intensive therapy unit. On day 11 of her admission, she rapidly deteriorated with evidence of refractory cardiogenic shock and neurological involvement, both features associated with a poor prognosis. Cross-specialty collaboration prompted a trial of veno-arterial extra-corporeal membrane oxygenation and Eculizumab, a complement inhibitor normally reserved for atypical haemolytic uraemic syndrome, as a bridge to organ recovery. To our knowledge, herein we present the first adult patient with haemolytic uraemic syndrome induced cardiogenic shock successfully supported to cardiac recovery with extra-corporeal membrane oxygenation. The potential role for Eculizumab in Shiga toxin-producing Escherichia coli/typical haemolytic uraemic syndrome is also discussed.

Shiga Toxin-Associated Hemolytic Uremic Syndrome: A Narrative Review

The severity of human infection by one of the many Shiga toxin-producing Escherichia coli (STEC) is determined by a number of factors: the bacterial genome, the capacity of human societies to prevent foodborne epidemics, the medical condition of infected patients (in particular their hydration status, often compromised by severe diarrhea), and by our capacity to devise new therapeutic approaches, most specifically to combat the bacterial virulence factors, as opposed to our current strategies that essentially aim to palliate organ deficiencies. The last major outbreak in 2011 in Germany, which killed more than 50 people in Europe, was evidence that an effective treatment was still lacking. Herein, we review the current knowledge of STEC virulence, how societies organize the prevention of human disease, and how physicians treat (and, hopefully, will treat) its potentially fatal complications. In particular, we focus on STEC-induced hemolytic and uremic syndrome (HUS), where the intrusion of toxins inside endothelial cells results in massive cell death, activation of the coagulation within capillaries, and eventually organ failure.

Typical or Atypical Hemolytic Uremic Syndrome and the Use of Eculizumab: 4 Illustrative Cases

Typical hemolytic uremic syndrome (HUS) in children is caused mostly by Escherichia coli 0157:H7 in our country. Atypical HUS (aHUS) causes include Streptococcus pneumoniae, methyl malonic aciduria, deficiency of ADAMST 13, and genetic or acquired disorder of the complement. Treatment of HUS relies on supportive measures while treatment of aHUS includes plasmapheresis and specific treatments. Recently, eculizumab has been proposed for the treatment of aHUS and many clinicians now believe that eculizumab should be the first-line standard of care. The purpose of this article is to illustrate the difficulties in the diagnostic process of HUS and therefore the subsequent problem to promptly choose the appropriate treatment. To date, workup of HUS continues to take many days leaving the clinicians with a choice between several therapeutic options. With the emergence of eculizumab, it becomes crucial to find faster diagnostic tools and to adapt HUS treatment protocols. We reported here clinical cases where eculizumab use was probably not appropriate once the correct diagnosis of typical HUS was made and cases where it would have been useful because of the late diagnosis of aHUS.

An outbreak of hemolytic uremic syndrome in southern Romania during 2015-2016: Epidemiologic, clinical, laboratory, microbiologic, therapeutic and outcome characteristics

BACKGROUND AND AIMS

To describe the epidemiologic, clinical, microbiological, therapeutic and outcome characteristics of a HUS outbreak occurring in southern Romania from 2015 to 2016.

METHODS

We retrospectively collected data from the medical records of all HUS cases hospitalized at the pediatric nephrology department of Marie Curie Children's Hospital of Bucharest, Romania.

RESULTS

There were 32 HUS cases (19 girls/13 boys, 87.6% <2 years), all associated with diarrhea (bloody in 13, 40.6%). Thirteen (40.6%) and 4 (12.5%) patients had oliguria and anuria at admission. Extreme pallor, generalized edema, vomiting, dehydration, fever and seizures were found in 100%, 56.3%, 31.3%, 31.3%, 25% and 9.4% of patients, respectively. E. coli and STEC were identified in the stools of 6 and 8 patients, respectively; E. coli O₂₆ and O₁₅₇ infection were documented serologically in 10 and 3 children, respectively. There were 15/32 (46.9%) patients with confirmed HUS. Eighteen (56.3%) patients were hypertensive; other complications included infections, left ventricular hypertrophy, cardiopulmonary arrest, seizures and encephalopathy in 62.5%, 37.5%, 28.3%, 18.8% and 12.5%, respectively. Peritoneal dialysis and hemodialysis were performed in 23 (72%) and 2 patients, respectively. Three patients (9.4%) died early during hospitalization. A 6-12-month follow-up of 26 patients revealed that 65.4% had post-HUS sequelae (persistent hypertension and chronic renal failure in 34.6% and 30.8%, respectively).

CONCLUSIONS

The principal STEC serotype involved was O₂₆:H₁₁ and the number of confirmed HUS cases reached half of the patients. Compared with the medical literature, this outbreak had a higher rate of complications and renal sequelae and was associated with a high fatality rate.

Postdiarrheal hemolytic and uremic syndrome with severe multiorgan involvement and associated early risk factors

AIM

Identifying early clinical and biological factors associated with severe forms of postdiarrheal hemolytic uremic syndrome (D+HUS) that may help practitioners determine appropriate treatment.

METHODS

This retrospective study was conducted in 49 children with D+HUS between 2001 and 2011. Severe forms were defined as occurrence of one of the following conditions: death, major neurological involvement, cardiovascular involvement, and/or the presence of sequelae (neurological, cardiovascular, pancreatic, or renal).

RESULTS

During the acute phase, 35 children exhibited at least one type of extrarenal involvement including 13 severe forms with a median delayed occurrence after admission of 4.5 days (range: 1-8) for comatose children and 5 days (range: 2-6) for cardiovascular involvement; 32 children required dialysis and three died. In multivariate analysis, (i) major neurological involvement (n=13), (ii) dialysis (n=32), and (iii) sequelae (n=12) were associated with (i) fever during the prodromal phase requiring dialysis at admission, (ii) C-reactive protein level (CRP) >22mg/L at admission, and (iii) major neurological involvement and a white blood cell count (WBC)>20×10³/mm³ during the acute stage, respectively.

CONCLUSIONS

D+HUS is a multiorgan disease with a delayed occurrence of life-threatening extrarenal organ involvement. Severe forms appear to be associated with early biological and clinical inflammatory parameters.

HUS-induced cardiac and circulatory failure is reversible using cardiopulmonary bypass as rescue

BACKGROUND

Extra-renal involvement in hemolytic uremic syndrome (HUS) includes gastrointestinal, pancreatic, hepatic, neurological and cardiac manifestations. The current 3-5% mortality rate in HUS patients is primarily attributed to complications related to the central nervous system and the heart. In this brief report, we illustrate that severe cardiac involvement in a patient with HUS is potentially reversible using cardiopulmonary bypass as rescue.

CASE-DIAGNOSIS/TREATMENT

A 12-year-old boy was diagnosed with enterohemorrhagic Escherichia coli-induced HUS related to E. coli serotypes O55:H7 and O121:H19. The patient developed anuria and hypertension of 150/105 mmHg and had neurological symptoms, with lethargy, confusion and later a tonic-clonic seizure successfully treated with midazolam. Laboratory tests on blood samples revealed acute renal failure, with a creatinine level of 3.98 mg/dL, thrombocytopenia of 47 × 10⁹/L, lactate dehydrogenase level of 3620 IU/L, low haptoglobin (<20 mg/dL), anemia (10.0 g/dL) and schistocytes on blood smears. Peritoneal dialysis was initiated without complications. Serum potassium level was normal. At day 3, the patient suffered cardiac arrest on two separate occasions. Troponin-T, creatine kinase and creatine kinase-MB levels were significantly increased. The second episode of cardiac arrest could not be reversed with advanced cardiopulmonary resuscitation, and a cardiopulmonary bypass circuit was established. Declining cardiac pump function to a near non-contractile state with an ejection fraction of <10% was observed on echocardiography. This persisted during the following days. After the patient had been on the cardiopulmonary bypass (CPB) circuit for 7 days, the myocardium slowly recovered function. Three days later, the CPB was successfully discontinued; the echocardiography showed near-normal ejection fraction, and electrocardiography (ECG) showed sinus rhythm.

CONCLUSIONS

Fatal outcome in patients with HUS may be the result of severe cardiac involvement. The present case illustrates the need for intensive supportive care, including the use of CPB, as the cardiac symptoms in HUS patients may be reversible. We suggest the monitoring of cardiac-specific enzymes, ECG and echocardiography in high-risk patients.

Direct cardiac involvement in childhood hemolytic-uremic syndrome: case report and review of the literature

Overhydration, hypertension, anemia, or dyselectrolytemias sometimes cause cardiovascular impairment in childhood hemolytic-uremic syndrome. Here, we report the case of a 4.5-year-old boy with hemolytic-uremic syndrome and sudden onset, 6 h later, of hemodynamic compromise secondary to a cardiac thrombotic micro-angiopathy. The child died. In the literature, we found 18 further cases with cardiac compromise ≤25 days after diagnosis. The following causes were found: micro-angiopathy, pericardial blood causing tamponade, and myocarditis.

CONCLUSION

We were able to document only 19 cases of childhood hemolytic-uremic syndrome complicated by a direct cardiac compromise. Nonetheless, we speculate that a direct cardiac compromise accounts for many cases of childhood hemolytic-uremic syndrome complicated by sudden death during the initial hospitalization. Hence, we propose to always measure troponin in children with hemolytic-uremic syndrome to detect a latent myocardial damage. What is Known: • Overhydration, hypertension, anemia, or dyselectrolytemias sometimes cause cardiovascular impairment in childhood hemolytic-uremic syndrome. What is New: • This study documents 19 cases of childhood hemolytic-uremic syndrome complicated by a direct cardiac compromise ≤ 25 days after diagnosis. • The Following causes were found: micro-angiopathy, pericardial blood causing tamponade, and myocarditis.

Acute Systolic Heart Failure Associated with Complement-Mediated Hemolytic Uremic Syndrome

Complement-mediated hemolytic uremic syndrome (otherwise known as atypical HUS) is a rare disorder of uncontrolled complement activation that may be associated with heart failure. We report the case of a 49-year-old female with no history of heart disease who presented with microangiopathic hemolytic anemia, thrombocytopenia, and acute kidney injury. Given her normal ADAMSTS13 activity, evidence of increased complement activation, and renal biopsy showing evidence of thrombotic microangiopathy, she was diagnosed with complement-mediated HUS. She subsequently developed acute hypoxemic respiratory failure secondary to pulmonary edema requiring intubation and mechanical ventilation. A transthoracic echocardiogram showed evidence of a Takotsubo cardiomyopathy with an estimated left ventricular ejection fraction of 20%, though ischemic cardiomyopathy could not be ruled out. Treatment was initiated with eculizumab. After several failed attempts at extubation, she eventually underwent tracheotomy. She also required hemodialysis to improve her uremia and hypervolemia. After seven weeks of hospitalization and five doses of eculizumab, her renal function and respiratory status improved, and she was discharged in stable condition on room air and independent of hemodialysis. Our case illustrates a rare association between acute systolic heart failure and complement-mediated HUS and highlights the potential of eculizumab in stabilizing even the most critically-ill patients with complement-mediated disease.

Extra-renal manifestations of complement-mediated thrombotic microangiopathies

Thrombotic microangiopathies (TMA) are rare but severe disorders, characterized by endothelial cell activation and thrombus formation leading to hemolytic anemia, thrombocytopenia, and organ failure. Complement over activation in combination with defects in its regulation is described in an increasing number of TMA and if primary for the disease denominated as atypical hemolytic-uremic syndrome. Although TMA predominantly affects the renal microvasculature, extra-renal manifestations are observed in 20% of patients including involvement of the central nerve system, cardiovascular system, lungs, skin, skeletal muscle, and gastrointestinal tract. Prompt diagnosis and treatment initiation are therefore crucial for the prognosis of disease acute phase and the long-term outcome. This review summarizes the available evidence on extra-renal TMA manifestations and discusses the role of acute and chronic complement activation by highlighting its complex interaction with inflammation, coagulation, and endothelial homeostasis.

Myocardial infarction is a complication of factor H-associated atypical HUS

Cardiac complications are frequently seen in thrombotic thrombocytopaenic purpura related to ADAMTS13 deficiency. We describe the case of a 43-year-old woman who was diagnosed with an atypical haemolytic-uraemic syndrome (aHUS) associated with a pathogenic mutation in the factor H gene (C623S). After 15 days of treatment, she suffered a sudden cardiac arrest and died despite intensive resuscitation attempts. She showed only one cardiovascular risk factor, hypercholesterolaemia. Her sudden death was secondary to cardiac infarction related to a coronary thrombotic microangiopathy. This is the first case of aHUS related to a mutation in the factor H gene associated with cardiac microangiopathy. This case emphasizes the need to screen for cardiac complication during the treatment of aHUS.

Hemolytic-uremic syndrome and myocardial dysfunction in a 9-month-old boy

Cardiovascular dysfunction in patients with hemolytic-uremic syndrome (HUS) may be related to secondary issues such as volume overload, hypertension or electrolyte disturbances including hyperkalemia. Additionally, primary myocardial involvement has been increasingly recognized as a potential comorbid feature of HUS. We report a 9-month-old child with HUS who developed clinical signs of poor myocardial function with depressed myocardial function noted by echocardiography. Supportive care including mechanical ventilation and inotropic agents were necessary for approximately 10 days. Follow-up echocardiography revealed return of normal ventricular function. Previous reports of primary cardiac involvement with HUS have included thrombotic microangiopathy of the coronary vasculature resulting in myocardial ischemia, myocardial infarction or depressed myocardial function, myocarditis, congestive heart failure with dilated cardiomyopathy and pericardial effusion with tamponade. Given the potential for morbidity and mortality during the preoperative period in patients with HUS, anesthesiologists involved in the care of such patients should be aware of the potential for myocardial involvement in this disease process. Preoperatively, the routine evaluation of myocardial function may be indicated.

Transient severe metastatic calcification in acute renal failure

Metastatic calcification, a known complication of prolonged end-stage renal disease, is herein described for the first time in a 10-month-old boy with acute renal failure, manifesting as a painful and swollen arm. Imaging revealed diffuse calcification and technetium-99 methylene diphosphonate (99Tc-MDP) uptake around the humerus and axilla. Calcium and vitamin D restriction, followed by intravenous administration of sodium thiosulfate caused a full symptomatic, radio- and scintigraphic improvement.

AN UNUSUAL TOXIC CAUSE OF HEMOLYTIC-UREMIC SYNDROME

Hemolytic uremic syndrome (HUS) has been associated with a variety of infective as well as non-infective causes. HUS as a toxic manifestation of exposure to herbicides/pesticides has not been reported so far in literature. We report a subject who presented with clinical features of features of HUS after intentional suicidal ingestion of the herbicidal agent monochloroacetic acid (MCA). A 55-year-old farmer was admitted with a history of consumption of monochloroacetic acid with vomiting, hematochezia and oligo-anuria. Our investigations revealed severe renal failure, metabolic acidosis, anemia, and thrombocytopenia with evidence of intravascular hemolysis. He was treated for HUS with plasma transfusions and haemodialysis in view of renal failure. During the course of hospital admission he developed acute antero-septal myocardial infarction and subsequently succumbed to the disease. MCA is used as an herbicidal agent and also a bleaching agent for silkworm cocoons. The toxicity of MCA has included metabolic acidosis, rhabdomyolysis and renal failure; however HUS has not been described in the literature. Extra -renal manifestations of HUS such as cardiomyopathy have also been infrequently described. This case is presented to highlight an as yet unknown toxicity of MCA.