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

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.

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.

Complement factor B mutation-associated aHUS and myocardial infarction

A 6-month-old female infant was referred with a 3-day history of low-grade fever, slight nasal congestion and rhinorrhoea. On admission, the clinical findings were unremarkable and she was discharged home. However, she became progressively more listless with a decreased urine output and was once again seen in the emergency department. Analytically she was found to have metabolic acidosis, hyperkalaemia, thrombocytopaenia, anaemia and schistocytes in the peripheral blood smear. Based on these findings, the diagnosis of haemolyticâ-uremic syndrome was made. A few hours postadmission, there was an abrupt clinical deterioration. She went into cardiorespiratory arrest and she was successfully resuscitated. An ST-segment elevation was noted on the ECG monitor and the troponin I levels were raised, suggesting myocardial infarction. Despite intensive supportive therapy, she went into refractory shock and died within 30 hours.

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.

Biomarkers detect involvement of acute myocardial injury in a paediatric haemolytic-uraemic syndrome patient

Although extrarenal manifestations of haemolytic-uraemic syndrome are not frequent, myocardial dysfunction should be given special consideration because of the importance of proper early haemodynamic management and potential complications. We report the case of a 21-month-old child with haemolytic-uraemic syndrome who developed clinical signs of poor myocardial function with depressed myocardial function noted by bedside echocardiography and significant elevation of biomarkers. Early intervention and supportive treatment for the patient were crucial during the acute phase of cardiac failure, and repeated monitoring of biomarkers and ecocardiography were useful diagnostic tools that provided relevant information throughout the patient's evolution.

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.

Cardiac tamponade in diarrhoea-positive haemolytic uraemic syndrome

The spectrum of extra-renal involvement secondary to diarrhoeal (D+) haemolytic uraemic syndrome (HUS) includes neurological, gastrointestinal, hepatic, pancreatic and cardiac complications. Among the cardiac complications, myocardial injury has been more commonly reported with HUS. Literature is scarce on HUS-associated pericardial involvement. We report a HUS-induced significant pericardial effusion that resulted in a cardiac tamponade. We also discuss the diagnostic and therapeutic implications of this complication.