Prevalence, risk factors, and outcomes of acute kidney injury in a pediatric cardiac intensive care unit: A cross-sectional study.

Background and Aims: Acute kidney injury (AKI) is a common complication in pediatric cardiac intensive care unit (CICU). This study aims to identify the prevalence, risk factors, and outcomes of AKI in pediatrics admitted to a CICU unit of a tertiary hospital. Methods: We retrospectively gathered the data of 253 randomly selected patients admitted to the CICU unit from March 2018 to March 2022. Data were collected from EHRs. We used the Kidney Disease Improving Global Outcomes (KDIGO) criteria for identifying AKI in patients. Results: Overall, AKI prevalence was 22.9% in our population. In the multivariable analysis, vancomycin intake (odds ratio [OR]: 2.109, 95% confidence interval [CI]: 1.15-3.84), angiography (OR: 4.38, 95% CI: 1.28-14.93), and mechanical ventilation (OR: 2.08, 95% CI: 1.02-4.23) were independent risk factors of AKI development and patients with AKI had a higher in-hospital mortality rate (OR: 5.81, 95% CI: 2.55-13.19), higher need for cardiopulmonary resuscitation (OR: 3.08, 95% CI: 1.17-8.09), and longer ICU length of stay (OR: 6.49, 95% CI: 3.31-9.67). Furthermore, furosemide administration was associated with lower risk of developing AKI (OR: 0.52, 95% CI: 0.27-0.97). Conclusion: AKI is common and is associated with worse outcomes in patients with congenital heart disease. Our results emphasize the importance of early identification and monitoring of AKI in the pediatric CICU setting.

Multisystem inflammatory syndrome in children and Kawasaki disease; comparison of their clinical findings and one-year follow-up-a cross-sectional study.

BACKGROUND: Studies on Multisystem Inflammatory Syndrome in Children (MIS-C) and Kawasaki Disease (KD) have yielded inconsistent results and are lacking in Asian and African countries. This study aimed to compare the laboratory and clinical features, short-term outcomes, and one-year follow-ups of a large cohort of MIS-C and KD patients. METHODS: Data from 176 MIS-C and 56 KD patients admitted to Tehran Children's Medical Center between January 2021 and January 2022 were collected. Patients were followed up until January 2023. RESULTS: While lymphopenia and thrombocytopenia were more prevalent in MIS-C (73.2% vs. 20% in KD, p < 0.001), KD patients exhibited a higher median white blood cell count and prevalence of anemia, along with higher fibrinogen and erythrocyte sedimentation rate levels (p < 0.001, p < 0.001, p = 0.005, p < 0.001, respectively). MIS-C patients also exhibited lower ejection fraction, a greater occurrence of pericardial effusion, and a higher incidence of coronary aneurysms and ectasia, and ascites. Echocardiography after seven days of treatment showed a reduction in pathologies for both groups, but it was significant only for MIS-C. After one year, coronary artery abnormalities remained in only six cases. CONCLUSIONS: In conclusion, this study highlights differences between MIS-C and KD, including laboratory indices as well as echocardiographic and abdominal ultrasound findings. These findings contribute valuable data on Iranian patients to the existing literature on this topic and have significant implications for accurate diagnosis and improved management of pediatric patients presenting with these conditions.

The role of nailfold capillaroscopy in pediatric patients with Kawasaki disease.

BACKGROUND: Nailfold capillaroscopy has been used as a non-invasive diagnostic method for microvasculature evaluation in various rheumatological disorders. The present study aimed to determine the utility of nailfold capillaroscopy in the diagnosis of Kawasaki Disease (KD). METHOD: In this case-control study nailfold capillaroscopy was performed in 31 patients with KD and 30 healthy controls. All nailfold images were evaluated for capillary distribution and capillary morphology such as enlargement, tortuosity, and dilatation of the capillaries. RESULT: Abnormal capillaroscopic diameter was identified in 21 patients from the KD group and 4 patients in the control group. The most common abnormality in capillary diameter was irregular dilatation in 11 (35.4%) KD patients and in 4 people (13.3%) in the control group. Distortions of the normal capillary architecture was commonly seen in the KD group (n=8). A positive correlation was observed between coronary involvement and abnormal capillaroscopic results (r=.65, P<.03). The sensitivity and specificity of capillaroscopy for the diagnosis of KD were 84.0% (95%CI: 63.9-95.5%) and 72.2% (95%CI: 54.8-85.8%), respectively. The PPV and NPV of capillaroscopy for KD were 67.7% (95%CI: 48.6-83.3) and 86.7% (95% CI: 69.3-96.2), respectively. CONCLUSION: Capillary alterations are more common in KD patients compared to control group. Thus, nailfold capillaroscopy can be useful in detecting these alterations. Capillaroscopy is a sensitive test for detecting capillary alternations in KD patients. It could be used as a feasible diagnostic modality for evaluating microvascular damage in KD.

The role of nailfold capillaroscopy in pediatric patients with Kawasaki disease / El papel de la capilaroscopia periungueal pacientes pediátricos con la enfermedad de Kawasaki

Background: Nailfold capillaroscopy has been used as a non-invasive diagnostic method for microvasculature evaluation in various rheumatological disorders. The present study aimed to determine the utility of nailfold capillaroscopy in the diagnosis of Kawasaki Disease (KD). Method: In this case–control study nailfold capillaroscopy was performed in 31 patients with KD and 30 healthy controls. All nailfold images were evaluated for capillary distribution and capillary morphology such as enlargement, tortuosity, and dilatation of the capillaries. Result: Abnormal capillaroscopic diameter was identified in 21 patients from the KD group and 4 patients in the control group. The most common abnormality in capillary diameter was irregular dilatation in 11 (35.4%) KD patients and in 4 people (13.3%) in the control group. Distortions of the normal capillary architecture was commonly seen in the KD group (n=8). A positive correlation was observed between coronary involvement and abnormal capillaroscopic results (r=.65, P<.03). The sensitivity and specificity of capillaroscopy for the diagnosis of KD were 84.0% (95%CI: 63.9–95.5%) and 72.2% (95%CI: 54.8–85.8%), respectively. The PPV and NPV of capillaroscopy for KD were 67.7% (95%CI: 48.6–83.3) and 86.7% (95% CI: 69.3–96.2), respectively. Conclusion: Capillary alterations are more common in KD patients compared to control group. Thus, nailfold capillaroscopy can be useful in detecting these alterations. Capillaroscopy is a sensitive test for detecting capillary alternations in KD patients. It could be used as a feasible diagnostic modality for evaluating microvascular damage in KD.(AU)

Antecedentes: La capilaroscopia periungueal se ha utilizado como un método diagnóstico no-invasivo para evaluación de la microvasculatura en varios trastornos reumatológicos. El presente estudio pretendió determinar la utilidad de la capilaroscopia periungueal en el diagnóstico de la enfermedad de Kawasaki (KD). Método: En este estudio de casos y controles se realizó la capilaroscopia periungueal para 31 pacientes con KD y 30 controles sanos. Todas las imágenes de la ungueal se evaluaron para la distribución capilar y la morfología capilar, como la ampliación, la tortuosidad y la dilatación de los capilares. Resultado: Se identificó un diámetro capilaroscópico anormal en 21 pacientes del grupo KD y en 4 pacientes del grupo control. La anomalía más común en el diámetro de los capilares fue la dilatación irregular en 11 (35,4%) pacientes con KD y 4 personas (13,3%) en el grupo control. Las distorsiones de la arquitectura capilar normal se observaron comúnmente en el grupo KD (n=8). Se observó una correlación positiva entre la afectación coronaria y los resultados capilares anormales (r=0,65, p <0,03). La sensibilidad y la especificidad de una capilaroscopia para el diagnóstico de KD fueron del 84,0% (IC del 95%: 63,9-95,5%) y del 72,2% (IC del 95%: 54,8-85,8%), respectivamente. El VPP y el VAN de la capilaroscopia para KD fueron del 67,7% (IC del 95%: 48,6-83,3) y del 86,7% (IC del 95%: 69,3-96,2), respectivamente. Conclusión: Las alteraciones capilares son más frecuentes en los pacientes con KD en comparación con el grupo control. Así, la capilaroscopia periungueal puede ser útil en la detección de estas alteraciones. La capilaroscopia es una prueba sensible para detectar las alteraciones capilares en pacientes con KD. Podría utilizarse como modalidad diagnóstica factible para evaluación el daño microvascular en la KD.(AU)

A novel mutation in the ALS2 gene in an iranian kurdish family with juvenile amyotrophic lateral sclerosis.

Amyotrophic lateral sclerosis (ALS) is a rare disorder that affects both upper and lower motor neurons. Mutations in Alsin Rho Guanine Nucleotide Exchange Factor (ALS2) correlates with three similar but distinctive syndromes, including the juvenile form of ALS. An Iranian Kurdish family was involved in this study and all members were evaluated with relevant clinical guidelines. Whole exome sequencing and sanger sequencing were applied to all family members to undermine the possible genetic factors. A substitution c. 2110 C>T (p. Arg704X) identified in the ALS2 gene. Bioinformatics analysis indicated the mutation is located in the well-conserved and functional domain of the protein. This study recognized a novel mutation in the ALS2 gene in a proband with the juvenile form of ALS. To our knowledge, this is the first identified ALS2 mutation among the Iranian population.

Intravenous Methylprednisolone Pulse Therapy Versus Intravenous Immunoglobulin in the Prevention of Coronary Artery Disease in Children with Kawasaki Disease: A Randomized Controlled Trial.

BACKGROUND: Kawasaki disease (KD) is often complicated by coronary artery lesion (CAL), including dilatation or aneurysms. Intravenous immunoglobulin (IVIG) is used with aspirin to prevent CAL in KD. OBJECTIVE: Given that the primary treatment for other vasculitis is the use of corticosteroids, this study has been performed to evaluate the effect of intravenous methylprednisolone pulse (IVMP) therapy in preventing CAL in KD. METHOD: A randomized, single-blind clinical trial was conducted on 40 KD patients aged six months to five years. Patients were randomized into two groups according to the main treatment plan in addition to aspirin: case group (IVMP for three consecutive days and then oral prednisolone for three days) and control group (intravenous immunoglobulin 2 g/kg). Echocardiography was performed for all children at least three times, during the acute phase, two weeks, and two months later. RESULTS: Data analysis at the end of the study was done on 40 patients (20 patients in each group). There were no significant differences in age and sex distribution, mean fever, and acute phase duration, as well as baseline echocardiography in the two groups. The frequency of CAL was 20% in the case group and 45% in the control group, after two weeks (p<0.05), but there was no significant difference between two groups in types of coronary artery lesion after two weeks and the frequency and severity of CAL after two months. CONCLUSION: IVMP as initial line therapy effectively control systemic and vascular inflammation and decrease coronary artery damage in KD.

Hematological indices in pediatric patients with acyanotic congenital heart disease: a cross-sectional study of 248 patients.

Background: Congenital heart disease CHD is a significant cause of mortality and morbidity in children worldwide. Patients with congenital heart disease may develop hematological problems, including thrombocytopenia and neutropenia. In addition, several studies indicate the higher frailty of patients with CHDs to infections and malignancies. Nevertheless, the mechanisms of immune system changes in these patients have remained in the shadow of uncertainty. Moreover, very few studies have worked on cytopenia in CHD. This study has assessed the frequency of thrombocytopenia, neutropenia, lymphopenia, and anemia in pediatric patients with acyanotic congenital heart disease ACHD prior to open-heart surgery. Methods: This cross-sectional study was handled in the Pediatric Cardiology Clinic, Tehran University of Medical Sciences, during pre-operation visits from 2014 till 2019. Two hundred forty-eight children and adolescents with acyanotic congenital heart disease before open-heart surgery met the criteria to enter the study. Results: A total of 191 (76.7%) patients with Ventricular Septal Defects (VSD), 37 (14.85%) patients with Atrial Septal Defects (ASD), and 20 (8.11%) patients with Patent Ductus Arteriosus (PDA) were enrolled in this study. The median age was 23.87 months. Thrombocytopenia and neutropenia were found, respectively, in 3 (1.2) and 23 (9.2%) patients. Hemoglobin level and lymphocyte count were significantly lower in patients with neutropenia than patients with normal neutrophil count (P value = 0.024 and P value = 0.000). Significant positive correlations were found between neutropenia and anemia. There were no correlations between neutrophil count and Platelets. Also, anemia was found in 48 patients (19.3%). The study also found a statistically significant correlation between the co-existence of VSD and neutropenia in the patients (P value = 0.000). Conclusion: Although most were mildly neutropenic, there was a significant correlation between neutropenia and Ventricular Septal Defect compared to PDA and ASD groups. Regarding the importance of neutropenia to affect the prognosis of congenital heart defects in infections, it is important to consider further studies on the status of immune system function in these patients.

Whole Exome Sequencing Identified the Causative Mutation in a 4-Year-Old Female with Mulibrey Nanism: A Case Report.

Mulibrey Nanism is a rare multisystem disorder inherited in an autosomal recessive manner caused by mutations in the TRIM37 gene. Most of the reported cases are from Finland, but this condition has rarely occurred in other countries. Although the clinical diagnosis of Mulibrey nanism is a challenge during the first months of life, the disease can be suspected clinically due to the distinctive features of the patients. A 4-year-old female with pneumonia, cardiomyopathy, growth retardation, peripheral edema, and characteristic craniofacial features was referred to Tehran Hope Generation Foundation Genetic diagnosis Center, in October 2021. Genomic DNA was isolated from peripheral blood samples of the patient and her parents and Whole exome sequencing was performed for the patient. Whole exome sequencing revealed a homozygous G>A splice site variant (TRIM37; c.370-1G>A). Sanger sequencing confirmed the segregation of the variant with phenotype in this family. Whole exome sequencing can be helpful in the diagnosis of the patients suspecting to Mulibrey nanism and lacking sufficient clinical presentation according to the diagnostic algorithm.

COVID-19: A New Horizon in Congenital Heart Diseases.

Objective: Previous studies have demonstrated that both children and adult patients with a history of congenital heart disease (CHD) are at high risk for coronavirus disease 2019 (COVID-19) infection. This study investigates the status of COVID-19 infection among children undergoing surgical repair within the past 2 years. Methods: All alive patients operated on in a tertiary referral center between March 2018 and March 2020 were recruited in the present study. Detailed demographics, past medical and surgical history, and physical examination were reviewed for each patient. During the COVID-19 pandemic, data regarding the patient's status were collected by telephone survey from April 15 to April 30, 2020. Results: A total number of 210 patients are analyzed in this study. Participants' median age was 21.59 months [interquartile range (IQR) = 12-54.67], and 125 (59.5%) were female. The median interval between surgery and COVID-19 assessment was 305 days (IQR = 215-400). In addition, 67 (32%) patients used angiotensin receptor blocker (ARB)/angiotensin-converting enzyme (ACE) inhibitor (spironolactone and/or captopril). Sixteen patients (7.6%) were symptomatic and had positive chest CT results and/or RT-PCR compared to the previously reported prevalence of COVID-19 among the pediatric population (2.4% of children with <18 years of age); the prevalence of COVID-19 among the patients operated on due to CHD in the present study was significantly higher (p = 0.00012). Two patients were admitted to the intensive care unit (ICU); one patient was discharged 2 weeks later with acceptable status, and one patient died 2 days after ICU admission due to cardiac and respiratory arrest and myocarditis. The complexity of the underlying cardiac disorders was not different between patients with low risk (p = 0.522), suspicious patients (p = 0.920), and patients positive for COVID-19 (p = 0.234). The ARB/ACE inhibitor consumption was not associated with the COVID-19 infection [p = 0.527, crude odds ratio (OR) = 1.407, 95% CI = 0.489-4.052]. Conclusion: Children with a history of previous CHD surgery are more susceptible to infections, especially those infections with pulmonary involvements, as the lung involvement could cause worsening of the patient's condition by aggravating pulmonary hypertension. The results of the current study indicate that these patients are more prone to COVID-19 infection compared to the healthy children population.

Little Hearts Are Affected by COVID19: Importance of the Myocardial Systolic Evaluation.

Background: Identifying the cardiac changes could help design measures to recover the cardiovascular system and lessen the mortality and morbidity rate. Accordingly, this cross-sectional study was performed to evaluate the echocardiography indices which are indicators of the cardiac alterations of the children with COVID19 infection. Methods: This study was performed as a cross-sectional study evaluating echocardiography indices in children infected with COVID19. Fifteen children, known cases of the COVID19, and 14 healthy children were enrolled. Evaluated parameters include left ventricle ejection fraction (LVEF), left ventricle end-diastolic diameter (LVED), mitral valve Sa (MV Sa), Tricuspid annular plane systolic excursion (TAPSE), and laboratory parameters. Results: The participants' mean age and weight were 62.8 (±48.0) months and 19.95 (±15.67) kg, respectively. None of the laboratory and echocardiography parameters differed between males and females, between patients with and without positive past medical history, between the patients with and without respiratory tract symptoms, and between patients with and without GI tract symptoms (P.0.05). Patients had significantly higher TAPSE (p = 0.027), although MV Sa (p = 0.01) was significantly higher among healthy children. LV EF (p = 0.425) and LVED diameter (p = 0.603) were not different significantly. None of the patients had pericardial effusion, pleural effusion, and cardiac tamponade. Conclusion: The heart can be involved during the disease course in children, even at the level of echocardiography indices. This could contribute to a worse prognosis, higher morbidity, and mortality rate, especially in patients with overt myocardial involvement. Non-classic indicators, including LVEF, may not be conclusive for cardiac involvement in non-symptomatic patients.

Giant intracardiac thrombosis in an infant with leukaemia and prolonged COVID-19 viral RNA shedding: a case report.

BACKGROUND: COVID-19 can induce thrombotic disease both in the venous and arterial circulations, as a result of inflammation, platelet activation, endothelial dysfunction, and stasis. Although several studies have described the coagulation abnormalities and thrombosis in adult patients with COVID-19, there is limited data in children. Here, we present an 18-month-old boy with a prolonged SARS-CoV-2 RNA shedding and chronic right atrial and superior vena cava (SVC) thrombosis. CASE PRESENTATION: An 18-month-old boy with acute lymphoblastic leukemia (ALL) (pre-B cell ALL) and a history of chemotherapy was referred to our center due to intermittent fever with unknown origin. a positive nasopharyngeal PCR for COVID-19 was reported and stayed positive for eight consecutive weeks The high-resolution computed tomography (HRCT) showed no sign of pulmonary embolism. Initial echocardiography indicated a semilunar thrombotic mass extending from right SVC into the right atrium without coronary or myocardial involvement. Enoxaparin was administered with continuous monitoring of the level of anti-Xa activity. The serial echocardiographic studies found a slow but continuous reduction in the mass size. CONCLUSIONS: Our case shows that, as already described in adult patients, clinically relevant thrombosis can complicate the course of pediatric patients as well. In view of the specific and milder manifestations of COVID-19 in children, these complications may pose considerable diagnostic and therapeutic challenges.

Mutational analysis of CYP1B1 gene in Iranian pedigrees with glaucoma reveals known and novel mutations.

PURPOSE: Primary congenital glaucoma (PCG) (OMIM#231,300) can be caused by pathogenic sequence variations in CYP1B1, LTBP2, MYOC and PXDN genes. The purpose of this study was to investigate mutations in the CYP1B1 gene in families affected with primary congenital glaucoma (PCG) using linkage analysis and Sanger sequencing. METHODS: A total number of four families with nine affected PCG patients during six months were included in this study. The mutations were identified by homozygosity mapping to find the linked loci and then direct sequencing of all coding exons, the exon-intron boundaries and the 5' untranslated region of CYP1B1 using genomic DNA obtained from affected family members and their parents. Moreover, bioinformatic tools were applied to study mutation effect on protein structure and function. RESULTS: A total of four mutations were identified, and three of these were novel. Two were missense mutations: One was truncating mutation, and the other was an in-frame deletion. Mutations in CYP1B1 could fully explain the PCG phenotype in all of the patients. Also, the bioinformatic study of the mutations showed the structure of the protein is affected, and it is well conserved among similar species. CONCLUSION: In this study, we identified 4 CYP1B1 mutations, 3 of which were novel. In silico analysis of identified mutations confirmed their molecular pathogenicity. A similar analysis will help understand the biological role of CYP1B1 and the effect of mutations on the regulatory and enzymatic functions of CYP1B1 that result in PCG. CLINICAL TRIALS REGISTRATION: Not relevant.

LRP8 (rs5177) and CEP85L (rs11756438) are contributed to schizophrenia susceptibility in Iranian population.

Introduction Schizophrenia is recognized as one of the most important mental illnesses of the last century. Many genetic and environmental factors are involved in this condition. Recently, the genome-wide association study identified two significant genes LRP8 and CEP85L associated with psychiatric disorders. LRP8 (low-density lipoprotein receptor-related protein 8) acts as a cytoplasmic receptor for Reelin. Many studies have revealed that LRP8 was significantly related to schizophrenia and bipolar disorder in Chinese population. CEP85L standing for 'centrosomal protein 85 kDa-like' is another gene, which has been reportedly associated with BPD. Methods We performed a case-control study to analyze the association between rs5177 single-nucleotide polymorphism in the LRP8 gene plus the single-nucleotide polymorphism rs11756438 in the CEP85L gene and schizophrenia in the Iranian population. The genotype for rs5177 was determined by ARMS PCR method, while for rs11756438 genotype, it was determined by PCR-RFLP method after which statistical analysis was performed for each polymorphism. In rs5177, the CC genotype was susceptible to the disease while G allele was associated with disease protection. Results and Conclusion In rs11756438, the AA genotype was associated with disease susceptibility, while allele A did not have a significant association with the disease.

Giant Thrombosis at Left Anterior Descending Artery Aneurysm in a 10-Year Old Boy with Granulomatosis with Polyangiitis.

Granulomatosis with polyangiitis (GPA), necrotizing vasculitis of small and medium-sized vessels, is traditionally believed to mainly affect respiratory tract with additional focal kidney involvements as its primary manifestations with a relatively rare annual incidence rate of 20-50 cases per million. Six percent of the affected cases have cardiac involvements; among which, aneurysms comprise the lowest penetrance. By this paper, we aim to cast light on clinical diagnostic and treatment methods of a rare case presentation, a 10-year-old male GPA patient, diagnosed with massive thrombosis at his coronary artery aneurysm. GPA should be considered as differential diagnosis of prolong fever and coronary aneurysms in adolescents.

Pulmonary artery-focused contrast echocardiography with supplemental oxygen(PCESO) for echocardiographic diagnosis of anomalous origin of left coronary artery from pulmonary artery: Novel use of an old technique.

Pulmonary artery-focused agitated saline contrast echocardiography unveils tricky cases of ALCAPA by the entry of microbubbles into the left coronary artery (LCA) during systole and retrograde flow from LCA into the main pulmonary artery during diastole. Associated pulmonary hypertension, if present, augments the former flow and supplemental oxygen increases the latter.

Investigation of Chromosomal Abnormalities and Microdeletion/ Microduplication(s) in Fifty Iranian Patients with Multiple Congenital Anomalies.

OBJECTIVE: Major birth defects are inborn structural or functional anomalies with long-term disability and adverse impacts on individuals, families, health-care systems, and societies. Approximately 20% of birth defects are due to chromosomal and genetic conditions. Inspired by the fact that neonatal deaths are caused by birth defects in about 20 and 10% of cases in Iran and worldwide respectively, we conducted the present study to unravel the role of chromosome abnormalities, including microdeletion/microduplication(s), in multiple congenital abnormalities in a number of Iranian patients. MATERIALS AND METHODS: In this descriptive cross-sectional study, 50 sporadic patients with Multiple Congenital Anomalies (MCA) were selected. The techniques employed included conventional karyotyping, fluorescence in situ hybridization (FISH), multiplex ligation-dependent probe amplification (MLPA), and array comparative genomic hybridisation (array-CGH), according to the clinical diagnosis for each patient. RESULTS: Chromosomal abnormalities and microdeletion/microduplication(s) were observed in eight out of fifty patients (16%). The abnormalities proved to result from the imbalances in chromosomes 1, 3, 12, and 18 in four of the patients. However, the other four patients were diagnosed to suffer from the known microdeletions of 22q11.21, 16p13.3, 5q35.3, and 7q11.23. CONCLUSION: In the present study, we report a patient with 46,XY, der(18)[12]/46,XY, der(18), +mar[8] dn presented with MCA associated with hypogammaglobulinemia. Given the patient's seemingly rare and highly complex chromosomal abnormality and the lack of any concise mechanism presented in the literature to justify the case, we hereby propose a novel mechanism for the formation of both derivative and ring chromosome 18. In addition, we introduce a new 12q abnormality and a novel association of an Xp22.33 duplication with 1q43q44 deletion syndrome. The phenotype analysis of the patients with chromosome abnormality would be beneficial for further phenotype-genotype correlation studies.

A Pathogenic Homozygous Mutation in The Pleckstrin Homology Domain of RASA1 Is Responsible for Familial Tricuspid Atresia in An Iranian Consanguineous Family.

OBJECTIVE: Tricuspid atresia (TA) is a rare life-threatening form of congenital heart defect (CHD). The genetic mechanisms underlying TA are not clearly understood. According to previous studies, the endocardial cushioning event, as the primary sign of cardiac valvulogenesis, is governed by several overlapping signaling pathways including Ras/ ERK pathway. RASA1, a regulator of cardiovascular development, is involved in this pathway and its haploinsufficiency (due to heterozygous mutations) has been identified as the underlying etiology of the autosomal dominant capillary malformation/arteriovenous malformation (CM/AVM). MATERIALS AND METHODS: In this prospective study, we used whole exome sequencing (WES) followed by serial bioinformatics filtering steps for two siblings with TA and early onset CM. Their parents were consanguineous which had a history of recurrent abortions. Patients were carefully assessed to exclude extra-cardiac anomalies. RESULTS: We identified a homozygous RASA1 germline mutation, c.1583A>G (p.Tyr528Cys) in the family. This mutation lies in the pleckstrin homology (PH) domain of the gene. The parents who were heterozygous for this variant displayed CM. CONCLUSION: This is the first study reporting an adverse phenotypic outcome of a RASA1 homozygous mutation. Here, we propose that the phenotypic consequence of the homozygous RASA1 p.Tyr528Cys mutation is more serious than the heterozygous type. This could be responsible for the TA pathogenesis in our patients. We strongly suggest that parents with CM/AVM should be investigated for RASA1 heterozygous mutations. Prenatal diagnosis and fetal echocardiography should also be carried out in the event of pregnancy in heterozygous parents.

A novel splicing variant in FLNC gene responsible for a highly penetrant familial dilated cardiomyopathy in an extended Iranian family.

Recent achievements in the genetic diagnosis of Dilated Cardiomyopathy (DCM) have disclosed rare variants in numerous genes encoding different types of myocardial proteins. However, the causative gene underlying the pathogenesis of about 60% of familial cases with DCM has not been identified. One novel gene introduced in 2016 for cardiac-restricted DCM is FLNC. In this study, we applied Whole Exome Sequencing (WES) and bioinformatics-based methods to a member of an extended non-consanguineous family with DCM history accompanied with fatal arrhythmia in at least four consecutive generations. We found a novel splice-site mutation in FLNC gene (c.2389+1G>A) which cosegregated with all symptomatic individuals in the family. Computational prediction software tools as well as RT-PCR method were used to evaluate the impact of the FLNC splice site mutation. This substitution leads to exon 15th donor-site disruption and exon skipping, which would result in a premature stop codon three aminocids downstream of the mutation site. The aberrantly mRNA transcript can induce nonsense-mediated mRNA decay. Although carrier individuals show remarkable variable expression regarding the severity of DCM as well as the disease age of onset, a highly penetrant fatal arrhythmia was found to be shared between them. We strongly suggest that the involvement of FLNC gene, due to haploinsufficiency, should be considered in familial cases with DCM, especially if accompanied with arrhythmia and increased incidence of sudden cardiac death.