Organic acidurias in Egyptian children: The urge for high-risk screening.

BACKGROUND: Organic acidurias are a group of inborn errors of metabolism. They present a significant diagnostic challenge and are associated with serious morbidity and mortality. They are considered the most frequent inborn errors of metabolism among high-risk children. Gas chromatography-mass spectrometry is a reliable diagnostic technique for organic acidurias. This hospital-based study aimed to quantify the frequency of organic acidurias among a group of high-risk Egyptian pediatric patients and to highlight the importance of high-risk screening for such disorders. METHODS: One hundred and fifty high-risk children who presented to the inherited metabolic disease unit and the pediatric intensive care units of Cairo University Children Hospital were tested for urine organic acids using gas chromatography-mass spectrometry. RESULTS: Thirty percent (45/150) of the patients were confirmed as having an altered organic acids profile. Neurological manifestations were the most common presentation. Glutaric aciduria type I and maple-syrup urine disease were the most common disorders encountered among the group that was studied. CONCLUSION: Organic acid detection by gas chromatography-mass spectrometry is key to the diagnosis of many metabolic disorders. Until a national expanded newborn screening program is established, high-risk screening is strongly encouraged for the early detection of, and proper intervention for such disorders among Egyptian children.

Molecular analysis of dilated and left ventricular noncompaction cardiomyopathies in Egyptian children.

BACKGROUND: Paediatric cardiomyopathy is a progressive, often lethal disorder and the most common cause of heart failure in children. Despite its severe outcomes, the genetic aetiology is still poorly characterised. High-throughput sequencing offers a great opportunity for a better understanding of the genetic causes of cardiomyopathy. AIM: The current study aimed to elucidate the genetic background of cardiomyopathy in Egyptian children. METHODS: This hospital-based study involved 68 patients; 58 idiopathic primary dilated cardiomyopathy and 10 left ventricular noncompaction cardiomyopathy. Cardiomyopathy-associated genes were investigated using targeted next-generation sequencing. RESULTS: Consanguinity was positive in 53 and 70% of dilated cardiomyopathy and left ventricular noncompaction cardiomyopathy patients, respectively. Positive family history of cardiomyopathy was present in 28% of dilated cardiomyopathy and 10% of the left ventricular noncompaction cardiomyopathy patients. In 25 patients, 29 rare variants were detected; 2 likely pathogenic variants in TNNI3 and TTN and 27 variants of uncertain significance explaining 2.9% of patients. CONCLUSIONS: The low genetic detection rate suggests that novel genes or variants might underlie paediatric cardiomyopathy in Egypt, especially with the high burden of consanguinity. Being the first national and regional report, our study could be a reference for future genetic testing in Egyptian cardiomyopathy children. Genome-wide tests (whole exome/genome sequencing) might be more suitable than the targeted sequencing to investigate the primary cardiomyopathy patients. Molecular characterisation of cardiomyopathies in different ethnicities will allow for global comparative studies that could result in understanding the pathophysiology and heterogeneity of cardiomyopathies.

Genetic study of pediatric hypertrophic cardiomyopathy in Egypt.

Paediatric cardiomyopathy is a progressive and often lethal disorder and the most common cause of heart failure in children. Despite their severe outcomes, their genetic etiology is still poorly characterised. The current study aimed at uncovering the genetic background of idiopathic primary hypertrophic cardiomyopathy in a cohort of Egyptian children using targeted next-generation sequencing. The study included 24 patients (15 males and 9 females) presented to the cardiomyopathy clinic of Cairo University Children's Hospital with a median age of 2.75 (0.5-14) years. Consanguinity was positive in 62.5% of patients. A family history of hypertrophic cardiomyopathy was present in 20.8% of patients. Ten rare variants were detected in eight patients; two pathogenic variants (8.3%) in MBPC3 and MYH7, and eight variants of uncertain significance in MYBPC3, TTN, VCL, MYL2, CSRP3, and RBM20.Here, we report on the first national study in Egypt that analysed sarcomeric and non-sarcomeric variants in a cohort of idiopathic paediatric hypertrophic cardiomyopathy patients using next-generation sequencing. The current pilot study suggests that paediatric hypertrophic cardiomyopathy in Egypt might have a particular genetic background, especially with the high burden of consanguinity. Including the genetic testing in the routine diagnostic service is important for a better understanding of the pathophysiology of the disease, proper patient management, and at-risk detection. Genome-wide tests (whole exome/genome sequencing) might be better than the targeted sequencing approach to test primary hypertrophic cardiomyopathy patients in addition to its ability for the identification of novel genetic causes.

Hypertrophic cardiomyopathy: prognostic factors and survival analysis in 128 Egyptian patients.

BACKGROUND: Hypertrophic cardiomyopathy is an important cause of disability and death in patients of all ages. Egyptian children may differ from Western and Asian patients in the pattern of hypertrophy distribution, clinical manifestations, and risk factors. OBJECTIVES: The aim of our study was to report the clinical characteristics and outcomes of Egyptian children with hypertrophic cardiomyopathy studied over a 7-year duration and to determine whether the reported adult risk factors for sudden cardiac death are predictive of the outcome in these affected children. STUDY DESIGN AND METHODS: This retrospective study included 128 hypertrophic cardiomyopathy children. The data included personal history, family history, physical examination, baseline laboratory measurements, electrocardiogram, and Holter and echocardiographic results. Logistic regression analysis was used for the detection of risk factors of death. RESULTS: Fifty-one out of 128 patients died during the period of the study. Of the 51 deaths, 36 (70.5%) occurred in patients presenting before 1 year of age. Only eight patients had surgical intervention. Extreme left ventricular hypertrophy, that is, interventricular septal wall thickness or posterior wall thickness Z-score >6, sinus tachycardia, and supraventricular tachycardia were found to be independent risk factors for prediction of death in patients with hypertrophic cardiomyopathy. CONCLUSIONS: At our Egyptian tertiary care centre, hypertrophic cardiomyopathy has a relatively worse prognosis when compared with reports from Western and Asian series. Infants have a worse outcome than children presenting after the age of 1 year. A poorer prognosis in childhood hypertrophic cardiomyopathy is predicted by an extreme left ventricular hypertrophy, the presence of sinus tachycardia, and supraventricular tachycardia.