A pediatric case of atypical hemolytic uremic syndrome (aHUS): Could any infection play a triggering role?

A 12-year-old boy was transferred to our pediatric department from a rural hospital for fever, cough, and vomiting associated with thrombocytopenia, non-immune hemolytic anemia, and acute kidney injury, leading to the diagnosis of hemolytic uremic syndrome (HUS). A nasopharyngeal swab and a lower respiratory sample detected Influenza A by polymerase chain reaction (PCR). The patient was treated with oseltamivir and intravenous fluids in addition to fresh frozen plasma (FFP). Enteropathogenic Escherichia coli (EPEC) was detected in a stool sample by PCR. Serum antibodies for Mycoplasma pneumoniae (IgM and IgG) and Helicobacter pylori (IgA and IgG) were increased. Further work-up revealed elevated serum C5b-9 suggesting a simultaneous viral and bacterial infection-mediated complement overactivation leading to the diagnosis of atypical HUS (aHUS). An association between aHUS and influenza A is reported in the literature, but the correlation of EPEC, Mycoplasma pneumoniae, and Helicobacter pylori with aHUS is not well-established. Fresh frozen plasma was administered for a total of 3 days, followed by clinical and laboratory improvement. The patient has remained asymptomatic until the latest follow-up, 5 months after discharge. This case demonstrates the potential triggering role of different pathogens in aHUS pathogenesis to raise awareness in the pediatric community.

Multisystem inflammatory syndrome in children (MIS-C): A nationwide collaborative study in the Greek population

Multisystem inflammatory syndrome in children (MIS-C) is a rare but severe hyperinflammatory condition that may occur following SARS-CoV-2 infection. This retrospective, descriptive study of children hospitalized with multisystem inflammatory syndrome in children (MIS-C) in 12 tertiary care centers from 3/11/2020 to 12/31/2021. Demographics, clinical and laboratory characteristics, treatment and outcomes are described. Among 145 patients (95 males, median age 8.2 years) included, 123 met the WHO criteria for MIS-C, while 112 (77%) had serological evidence of SARS-CoV-2 infection. Fever was present in 99%, gastrointestinal symptoms in 77%, mucocutaneous involvement in 68% and respiratory symptoms in 28%. Fifty-five patients (38%) developed myocarditis, 29 (20%) pericarditis and 19 (13%) coronary aneurysms. Among the above cases 11/55 (20%), 1/29 (3.4%) and 5/19 (26.3%), respectively, cardiac complications had not fully resolved at discharge. Underlying comorbidities were reported in 18%. Median CRP value was 155 mg/l, ferritin 535 ng/ml, PCT 1.6 ng/ml and WBC 14.2 × 109/mm3. Most patients had elevated troponin (41.3%) and/or NT-pro-BNP (49.6%). Intravenous immunoglobulin plus corticosteroids were used in 117/145 (80.6%), monotherapy with IVIG alone in 13/145 (8.9%) and with corticosteroids alone in 2/145 (1.3%). Anti-IL1 treatment was added in 15 patients (10.3%). Thirty-three patients (23%) were admitted to the PICU, 14% developed shock and 1 required ECMO. Mortality rate was 0.68%. The incidence of MIS-C was estimated at 0.69/1000 SARS-CoV-2 infections. Patients who presented with shock had higher levels of NT-pro-BNP compared to those who did not (p < 0.001). Acute kidney injury and/or myocarditis were associated with higher risk of developing shock.

CONCLUSION

MIS-C is a novel, infrequent but serious disease entity. Cardiac manifestations included myocarditis and pericarditis, which resolved in most patients before discharge. Timely initiation of immunomodulatory therapy was shown to be effective. NT-pro-BNP levels may provide a better prediction and monitoring of the disease course. Further research is required to elucidate the pathogenesis, risk factors and optimal management, and long-term outcomes of this clinical entity.

WHAT IS KNOWN

• MIS-C is an infrequent but serious disease entity. • Patients with MIS-C present with multi-organ dysfunction, primarily involving the gastrointestinal and cardiovascular systems.

WHAT IS NEW

• NT-pro-BNP levels may provide a better prediction and monitoring of the disease course. • Acute kidney injury and/or myocarditis were associated with higher risk of developing shock.

Genital Abnormalities and Growth Retardation as Early Signs of Dilated Cardiomyopathy with Ataxia Syndrome

Dilated cardiomyopathy with ataxia syndrome is a rare mitochondrial disease caused by autosomal recessive mutations in the DNAJC19 gene. The disease has been described in detail in the Canadian Hutterite population, but a few sporadic cases with de novo mutations have been published worldwide. We describe a homozygous pathogenic variant in the DNAJC19 gene, diagnosed in Northern Greece, presenting with genital anomalies, growth failure, cardiomyopathy, and ataxia, but without increased urinary 3-methylglutaconic acid and additional presence of vitamin D disorders, hypercalciuria, and osteopenia. This case not only expands the clinical characteristics of 3-methylglutaconic aciduria type V (MGCA5) but also highlights the power of genetic analysis for detecting a diagnosis when the metabolic screen is negative.

Beckwith-Wiedemann syndrome with multiple hepatic and cutaneous hemangiomas in a female patient of Albanian origin: Diagnostic and therapeutic considerations

We describe a 2-month-old female infant with macroglossia, macrosomia, omphalocele, neonatal hypoglycemia, earlobe creases, low nasal bridge, midface retrusion, syndromic facies and multiple cutaneous and hepatic hemangiomas (HH). Genetic evaluation confirmed the diagnosis of Beckwith-Wiedemann Syndrome (BWS) with mosaic uniparental disomy 11 as the underlying genetic mechanism suggested by partial hypermethylation of H19/IGF2:IG-DMR and partial hypomethylation of KCNQ1OT1:TSS-DMR on chromosome 11p15.5. Pediatric endocrinology and cardiology assessments were normal. No malignant liver or renal tumors were detected during the follow-up period. Treatment with propranolol was started for the multiple HH, according to international recommendations. At 3-, 6-, and 9-month follow up, a gradual decrease in the size of the hemangiomas and AFP levels was observed, without side effects. This is the fifth case in the literature combining HH and BWS, and among these, the third case with this specific genetic defect suggesting a possible association between HH and BWS caused by 11 paternal uniparental disomy [upd(11)pat]. The case also highlights that if treatment is warranted, then oral propranolol can be used for the management of infantile HH in BWS patients similarly to non-BWS patients.

Α rare case of myopathy, lactic acidosis, and severe rhabdomyolysis, due to a homozygous mutation of the ferredoxin-2 (FDX2) gene

Mitochondrial myopathy is a severe metabolic myopathy related to nuclear or mitochondrial DNA dysfunction. We present a rare case of mitochondrial myopathy, presented with multiple episodes of proximal muscle weakness, lactic acidosis, and severe rhabdomyolysis (CPK 319,990 U/L, lactic acid 22.31 mmol/L, and GFR 3.82 mL/min/1.73m2 ). She was hospitalized in the pediatric intensive care unit due to acute kidney injury, elevated blood pressure, and deterioration of respiratory and cardiac function. Investigation for inherited metabolic disorders showed elevated levels of ammonia, lactic acid to pyruvic acid ratio, and urine ketone bodies. Exome sequencing detected a homozygous pathogenic variant in FDX2 (ENST00000541276:p.Met4Leu/c.10A > T) and a heterozygous variant of uncertain significance in MSTO1 (ENST00000538143:p.Leu137Pro/c.410 T > C). After Sanger sequencing, the p.Met4Leu pathogenic variant in FDX2 (ENST00000541276:p.Met4Leu/c.10A > T) was identified in a heterozygous state in both her parents and sister. Recently, pathogenic variants in the FDX2 gene have been associated with mitochondrial myopathy, lactic acidosis, optic atrophy, and leukoencephalopathy. Only four reports of FDX2-related rhabdomyolysis have been described before, but none of the previous patients had hyperammonemia. This is a rare case of severe mitochondrial myopathy in a pediatric patient related to a pathogenic FDX2 variant, suggesting the need for genetic analysis of the FDX2 gene in cases of suspicion of mitochondrial myopathies.

Multisystem inflammatory syndrome in a child with low inflammatory markers, persistent hyponatremia, and natriuresis

BACKGROUND

Multisystem inflammatory syndrome in children (MIS-C) is a rare complication after infection with Coronavirus disease 2019 (COVID-19), and the differential diagnosis from Kawasaki disease is predominantly based on patients' older age and positive anti-SARS-CoV-2 antibodies in most cases.

CASE DESCRIPTION

We report an "atypical" case of MIS-C in a 3.5-year-old child, with relatively low levels of inflammatory markers, persistent hyponatremia, and hypoalbuminemia, along with exceptionally high levels of brain natriuretic peptide (BNP) and myocardial dysfunction. Persistent hyponatremia was mainly related to natriuresis, while BNP elevation was a marker of the disease severity, reflecting abnormal cardiac function.

CONCLUSION

Low inflammatory markers in children under the age of five years should not exclude a possible diagnosis of MIS-C. HIPPOKRATIA 2022, 26 (2):83-85.

Similar Myocardial Perfusion and Vascular Stiffness in Children and Adolescents with High Lipoprotein (a) Levels, in Comparison with Healthy Controls

Background and Aims

This study investigated the possible correlation between elevated lipoprotein (a) (Lp(a)) levels and early vascular aging biomarkers in healthy children and adolescents.

Methods

Twenty-seven healthy children/adolescents, mean age 9.9 ± 3.7 years, with high Lp(a) levels without other lipid abnormalities and 27 age- and sex-matched controls with normal Lp(a) levels, were included in the study. The investigation of possible early vascular aging was assessed by measuring vascular function indices: carotid intima-media thickness (c-IMT), pulse wave velocity (PWV), augmentation index (AIx), and subendocardial viability ratio (SEVR).

Results

Although serum lipid values were within normal levels, mean values of total cholesterol and apolipoprotein B were higher in the group of children with high Lp(a) levels than controls (p = 0.006 and p < 0.001, respectively). Vascular function indices did not show significant differences, neither between the 2 groups nor in the subgroups of children with increased Lp(a) levels. These subgroups were defined by the presence or absence of family history of premature coronary artery disease. Lp(a) levels did not show a significant correlation with the other parameters studied, both regarding the whole sample (patients and controls), as well as in the subgroups of elevated Lp(a) levels. However, in the group of children with high Lp(a) levels, c-IMT and PWV were positively correlated with diastolic blood pressure (r = 0.427, p = 0.026 and r = 0.425, p = 0.030, respectively), while SEVR was negatively correlated with AIx (r = -0.455, p = 0.017).

Conclusions

Healthy children and adolescents with high Lp(a) levels do not yet have impaired vascular indices, compared to controls. However, in order to prevent early atherosclerosis, it is crucial to early identify and follow up children with high Lp(a) levels and positive family history of premature coronary disease or other cardiovascular risk factors.

Association Between Serum Lipid Levels in Greek Children with Dyslipidemia and Mediterranean Diet Adherence, Dietary Habits, Lifestyle and Family Socioeconomic Factors

Background: Childhood dyslipidemia is an important risk factor for developing cardiovascular disease in adulthood. Our study aimed to investigate a possible correlation between nutritional, lifestyle, behavioral and socioeconomic factors and serum lipid levels in children with dyslipidemia. Methods: In this retrospective, observational study, in 31 children with dyslipidemia, aged 3–14 years, dietary habits, physical activity, hours watching television or playing video games, family’s socioeconomic status, weight of children and parents, and duration of breastfeeding were recorded. The children’s adherence to the Mediterranean diet was also evaluated by KidMed index. Statistical analysis was performed using SPSS.22. Results: Children with increased physical activity had lower triglyceride levels, compared to those with lower physical activity (p = 0.001). Children who consumed only one meal per day, had increased levels of total cholesterol (p = 0.01), LDL-cholesterol (p = 0.01), ApoB (p = 0.001) and lipoprotein (a) (p = 0.018), compared to those who consumed more than 3 meals per day (p < 0.05). Children who were breastfed less than 6 months had significantly increased LDL-C levels (p = 0.022), compared to children who were breastfed more than 6 months. All other parameters investigated did not differ significantly. Conclusions: This study showed association between lipid profile of children with dyslipidemia and specific nutritional and socioeconomic factors, such as increased physical activity, increased meals consumption during the day, and exclusive breastfeeding for more than 6 months. Nevertheless, further research is needed, in order to confirm these findings.

Familial Mediterranean fever and atherosclerosis in childhood and adolescence

Familial Mediterranean fever is a chronic inflammatory disease characterized by periodic and self-limited episodes of fever and aseptic polyserositis. Although colchicine treatment has altered the course of the disease, it is believed that subclinical inflammation is still present, leading to endothelial dysfunction and atherosclerosis in the course of time. In this review, following the published recommendations, we queried online databases such as MEDLINE Pubmed, Scopus, and Web of science for peer-reviewed studies and reviews written in English language, using the following keywords: familial Mediterranean fever, children, endothelial dysfunction, atherosclerosis, cardiovascular disease. The objective of this review is to highlight the correlation between familial Mediterranean fever and atherosclerosis, and moreover to describe new serum inflammatory markers and non-invasive methods of endothelial dysfunction, to detect the atherosclerosis process early starting from childhood.

Obesity and season as determinants of high blood pressure in a school-based screening study

This school-based screening study assessed the prevalence of high blood pressure (BP) levels according to the European Society of Hypertension (ESH) 2016 guidelines. Moreover, risk factors for BP elevation, and the effect of geographic and seasonal factors on BP screening were investigated. BP and anthropometric measurements were obtained from 2832 children and adolescents, aged 6-18 years, during the period 2013-2016. Three BP measurements were performed using a mercury sphygmomanometer, and the mean of the last two was used for the analysis. Obesity was defined according to the International Obesity Task Force (IOTF) criteria. The prevalence of high-normal BP/hypertension and overweight/obesity was 3.7%/0.9%, and 22.9%/8.5%, respectively. The majority of the participants presenting high BP (≥90th percentile) were overweight or obese. Increased prevalence of high BP was observed during spring (5.5%) and winter (5%) compared with 2.5% in autumn (P<0.05). SBP z scores were higher in males, during spring and summer, and in urban areas. In conclusion, a low rate of high-normal and hypertensive BP levels was found despite the high prevalence of overweight and obesity. Overweight and obesity were associated with higher BP levels, but there was also a seasonal difference in the prevalence of high BP levels.

Could vitamin D deficiency influence left heart ventricular geometry in youngsters with type 1 diabetes mellitus?

BACKGROUND

Experimental and clinical studies have shown the cardio-protective, anti-inflammatory, and anti-atherosclerotic actions of vitamin D.

MATERIAL AND METHODS

We aimed to investigate a possible correlation between vitamin D status and heart geometry using echocardiographic parameters of the left ventricle in youngsters with type 1 diabetes mellitus (T1D). Seventy-eight pediatric patients (aged 13.47 ± 2.86 years) with T1D of more than two years duration and 74 healthy controls (aged 12.04 ± 2.79 years) were enrolled in this case-control study. Anthropometric parameters were recorded, vitamin D and parathormone serum levels were measured, and trans-thoracic echocardiographic study was performed.

RESULTS

Vitamin D deficiency was found in 74 % T1D patients and in 72 % of the controls, while parathormone levels were normal in both groups. T1D patients presented significantly higher values of interventricular septal thickness at diastole (IVSD) compared to controls (0.76 ± 0.16 cm vs 0.71 ± 0.14 cm, p =0.043). All other echocardiographic parameters did not exhibit significant differences between patients and controls. The diastolic function of the left ventricle (LV) was normal in both groups. After sub-grouping, the participants according to the deficiency or not of vitamin D, only patients with T1D and low vitamin D levels had increased values of IVSD compared to controls (0.78 ± 0.17 vs 0.71 ± 0.14, p =0.008). Patients with T1D and normal vitamin D levels presented similar values of IVSD compared to controls (0.71 ± 0.12 vs 0.73 ± 0.15, p =NS).

CONCLUSIONS

Children and adolescents with T1D and normal vitamin D levels do not exhibit changes in LV dimensions or diastolic function, except for increased IVSD, compared to controls. Larger and longitudinal studies are required to confirm and consolidate this finding. HIPPOKRATIA 2019, 23(1): 9-14.

Broadening the Picture of Short-Chain Acyl-CoA Dehydrogenase Deficiency: A Case Report with Microcephaly, Leukoencephalopathy, and Characteristic Magnetic Resonance Spectroscopic Findings

Short-chain acyl-CoA dehydrogenase deficiency (SCADD) is a mitochondrial fatty acid metabolism disorder, which results in the accumulation of butyrylcarnitine and ethylmalonic acid in blood and urine. Evidence of genotype/phenotype correlation and neuroimaging characteristics is limited compared with other inborn errors of metabolism. We report a male patient with SCADD who initially presented with seizures, metabolic acidosis, microcephaly, and developmental delay with gradual amelioration of most symptoms. MRI/MRS revealed extended multifocal leukoencephalopathy, disturbed myelination, and abnormal brain energy metabolism with low choline/creatine ratio, which indicate the need for MRI/MRS follow-up even for asymptomatic patients with SCADD.

Truncated prelamin A expression in HGPS-like patients: a transcriptional study

Premature aging syndromes are rare genetic disorders mimicking clinical and molecular features of aging. A recently identified group of premature aging syndromes is linked to mutation of the LMNA gene encoding lamins A and C, and is associated with nuclear deformation and dysfunction. Hutchinson-Gilford progeria syndrome (HGPS) was the first premature aging syndrome linked to LMNA mutation and its molecular bases have been deeply investigated. It is due to a recurrent de novo mutation leading to aberrant splicing and the production of a truncated and toxic nuclear lamin A precursor (prelamin AΔ50), also called progerin. In this work and based on the literature data, we propose to distinguish two main groups of premature aging laminopathies: (1) HGPS and HGP-like syndromes, which share clinical features due to hampered processing and intranuclear toxic accumulation of prelamin A isoforms; and (2) APS (atypical progeria syndromes), due to dominant or recessive missense mutations affecting lamins A and C. Among HGPS-like patients, several deleted prelamin A transcripts (prelamin AΔ50, AΔ35 and AΔ90) have been described. The purpose of this work was to characterize those transcripts in eight patients affected with HGP-like rare syndromes. When fibroblasts were available, the relationships between the presence and ratios of these transcripts and other parameters were studied, aiming to increase our understanding of genotype-phenotype relationships in HGPS-like patients. Altogether our results evidence that progerin accumulation is the major pathogenetic mechanism responsible for HGP-like syndromes due to mutations near the donor splice site of exon 11.

Correlation of plasma B-type natriuretic peptide with shunt volume in children with congenital heart disease involving left-to-right shunt

INTRODUCTION

Concentrations of B-type natriuretic peptide (BNP) are recognised as a reliable marker of ventricular dysfunction in adults. In this study, plasma levels of BNP were determined in children with congenital heart disease (CHD) involving a left-to-right shunt, and were correlated with the shunt volume.

METHODS

Seventy-six children (38 boys/38 girls, mean age 22.4 months) with CHD (Group A: 31 with atrial septal defect [ASD], 23 with ventricular septal defect [VSD], 8 with ASD and VSD, 14 with patent ductus arteriosus [PDA]) and 34 healthy children (group B) were studied. BNP was measured by chemiluminescent microparticle immunoassay in all children. The amount of shunt (the ratio of pulmonary blood flow/systemic blood flow: Qp/Qs) was measured using Doppler velocimetry and two-dimensional echocardiography. A haemodynamically significant left-to-right shunt was defined as Qp/Qs>1.5. Correlations were evaluated between all patient groups and healthy subjects and BNP was compared with echocardiographic data reflecting right and left ventricle volume overload.

RESULTS

Thirty-four children of group A had Qp/Qs>1.5 (group A1) and 42 Qp/Qs<1.5 (group A2). BNP levels were higher in group A1 than group A2 (p=0.015), while there were no significant differences in BNP between group A2 and group B (p=0.79). BNP 24.4 pg/ml was determined as the cut-off point to identify patients with Qp/Qs>1.5. BNP values were similar among patients with ASD and VSD, but they were significantly higher in patients with PDA. BNP was positively correlated with Qp/Qs (r=0.59, p<0.001), and with the pulmonary artery velocity (r=0.27) and gradient (r=0.49), while there was a negative correlation with ejection fraction (r=-0.14). BNP levels were significantly higher in 10 infants with clinical signs of heart failure (p=0.025).

CONCLUSION

These results, which are consistent with previous reports, suggest a possible role of BNP as an early diagnostic marker of the significance of shunt in children with CHD.

Cardiac complications and immunophenotypic profile of infectious mononucleosis syndrome in children

OBJECTIVE

To investigate cardiac complications in infectious mononucleosis patients and to associate them with biochemical and immunological parameters, as well as with spleen ultrasound findings.

DESIGN

Cross-sectional study with follow-up.

SETTING

Tertiary care pediatric unit, in the city of Thessaloniki, Greece.

PARTICIPANTS AND INTERVENTIONS

Twenty-five children (15 boys, aged 1-11.6 years) suffering from infectious mononucleosis were studied during the acute phase and after 3-6 months. Cardiac evaluation comprised of electrocardiogram, echocardiogram, and measurement of creatine phosphokinase, creatine phosphokinase cardiac isoenzyme, and troponin levels. Biochemical and immunological tests included serum transaminases, serum amylase, CD3+/CD8+ T-lymphocytes subpopulation and CD4+/CD8+ T-lymphocytes ratio.

RESULTS

During acute phase, all children had splenomegaly and normal serum amylase values. 17 patients had elevated serum transaminases. Percentages of CD3+/CD8+ T-lymphocytes subpopulation were elevated and CD4+/CD8+ ratio was decreased in all patients. Echocardiography revealed mild pericardial effusion in 13 patients (10/21 with Epstein-Barr infection, 3/4 with cytomegalovirus infection), but none presented with myocarditis. Four out of these 13 patients also had markedly elevated liver enzymes, 10/13 had significant splenomegaly and 12/13 presented very low CD4+/CD8+ T-lymphocytes ratio. Pericardial effusion demonstrated a statistically significant association solely with very low CD4+/CD8+ T-lymphocytes ratio (<0.5). Repetition of laboratory tests 3-6 months post-discharge detected persistent mild pericardial effusion in five patients, along with decreased CD4+/CD8+ ratio in 1/5.

CONCLUSIONS

In infectious mononucleosis syndrome, asymptomatic pericardial effusion could be associated with very low CD4+/CD8+ ratio (<0.5). Further studies would extend and confirm such an association.

Cardiac manifestations of inborn errors of metabolism

AIM

The aim of the study was to investigate the frequency and type of cardiac manifestations in a defined group of patients with inborn errors of metabolism. This paper also explores the key role of cardiac manifestations in the diagnosis of inborn errors of metabolism in daily practice.

METHODS

Out of the 287 patients with the potential for inborn errors of metabolism who had been referred to the University Hospital of Heraklion (202 children and adolescents and 85 adults), 41 were found to have a variety of cardiac manifestations, including cardiomyopathy, cardiomegaly, atrioventricular conduction disorders and coronary artery disease.

RESULTS

In 15 out of the 41 patients a diagnosis of inborn errors of metabolism was established, while the total number of patients with inborn errors of metabolism was 60 out of the 287. In 6 out of the 15 patients the major symptoms were from the cardiovascular system and 7 of them were adults with symptoms initiating in childhood.

CONCLUSION

The cardiac findings consist of a neglected area in the diagnosis of the inborn errors of metabolism. Neurologists, pediatricians and internists should cooperate with cardiologists in managing people with unexplained cardiac symptoms and signs and be aware that several inborn errors of metabolism are associated with cardiac abnormalities and mild neurologic findings.