New Born Screening of Hemoglobinopathies in a Center Tunisian Population.

Sickle cell diseases, ß-thalassemia, and other hemoglobinopathies are common in Africa. Their distribution differs from one region to another. There are higher frequencies in Western and Northern Africa. Their clinical complications presented a real public health problem in each country. For this, early treatment can improve the severity of these diseases. Hemoglobinopathies targeted by screening are associated with SCD, ß, and α thalassemia. Our study aim is to report our experience with newborn screening for hemoglobinopathy in Tunis. The 156 newborn's cord blood was collected at the time of childbirth in the center region (Farhat Hached Hôspital). We opted for hemoglobin exploration to achieve maximum efficiency and effectiveness in screening. After that, all patients suspected to have hemoglobinopathies are affected by molecular investigation. Our findings showed the presence of some hemoglobinopathies such as ß-thalassemia and α-thalassemia with the following frequencies: 12% and 0.33%. The molecular results show the presence of HBB: c.93-21G>A, IVS-I-110G>A, HBBc. -106G>A -56G>C, HBBc.404T>C, Hb Yaounde described for the first time in Tunisia and α 3,7 . In conclusion, newborn screening diagnoses neonates with different examples of hemoglobinopathies, which will be beneficial not only for the care of the child but also for genetic counseling of the potential risk's parents.

Disorders of sex development in Wolf-Hirschhorn syndrome: a genotype-phenotype correlation and MSX1 as candidate gene.

BACKGROUND: Wolf-Hirschhorn (WHS) is a set of congenital physical anomalies and mental retardation associated with a partial deletion of the short arm of chromosome 4. To establish a genotype-phenotype correlation; we carried out a molecular cytogenetic analysis on two Tunisian WHS patients. Patient 1 was a boy of 1-year-old, presented a typical WHS phenotype while patient 2, is a boy of 2 days presented an hypospadias, a micropenis and a cryptorchidie in addition to the typical WHS phenotype. Both the array comparative genomic hybridization and fluorescence in situ hybridization techniques were used. RESULTS: Results of the analysis showed that patient 2 had a greater deletion size (4.8 Mb) of chromosome 4 than patient 1 (3.4 Mb). Here, we notice that the larger the deletion, the more genes are likely to be involved, and the more severe the phenotype is likely to be. If we analyze the uncommon deleted region between patient1 and patient 2 we found that the Muscle Segment Homeobox (MSX1) gene is included in this region. MSX1 is a critical transcriptional repressor factor, expressed in the ventral side of the developing anterior pituitary and implicated in gonadotrope differentiation. Msx1 acts as a negative regulatory pituitary development by repressing the gonadotropin releasing hormone (GnRH) genes during embryogenesis. We hypothesized that the deletion of MSX1 in our patient may deregulate the androgen synthesis. CONCLUSION: Based on the MSX1 gene function, its absence might be indirectly responsible for the hypospadias phenotype by contributing to the spatiotemporal regulation of GnRH transcription during development.

Nonketotic Hyperglycinemia in Tunisia. Report upon a Series of 69 Patients.

AIM: The aim of the study is to report on epidemiological, clinical, and biochemical characteristics of nonketotic hyperglycinemia (NKH) in Tunisia. METHODS: Patients diagnosed with NKH in Laboratory of Biochemistry at Rabta hospital (Tunis, Tunisia) between 1999 and 2018 were included. Plasma and cerebrospinal fluid (CSF) free amino acids were assessed by ion exchange chromatography. Diagnosis was based on family history, patient's clinical presentation and course, and increased CSF to plasma glycine ratio. RESULTS: During 20 years, 69 patients were diagnosed with NKH, with 25 patients originating from Kairouan region. Estimated incidences were 1:55,641 in Tunisia and 1:9,684 in Kairouan. Consanguinity was found for 73.9% of the patients and 42% of the families have history of infantile death due to a disease of similar clinical course than the propositus. Clinical symptoms initiated within the first week of life in 75% of the patients and within the first 3 months in 95.7% ones. The phenotype was severe in 76.8% of the patients. Main symptoms were hypotonia, feeding difficulties, coma, apnea, and seizures. Most patients died within few days to months following diagnosis. CSF to plasma glycine ratio was increased in all patients. CSF and plasma glycine levels were negatively correlated with age of disease onset and severity. CONCLUSION: NKH is quite frequent in Tunisia. Kairouan region has the highest NKH incidence rate, worldwide. However, due to lack of confirmatory enzymatic and genetic tests, NKH diagnosis was based on first-line biochemical tests. Characterization of causal mutations is needed for accurate diagnosis and prenatal diagnosis of this devastating life-threatening disease.

Molecular characterization of respiratory syncytial virus circulating in Tunisia between 2015 and 2018.

Introduction. Respiratory syncytial virus (RSV) is the most frequently identified viral agent in children with lower respiratory tract infection (LRTI). No data are available to date regarding RSV genotypes circulating in Tunisia.Aim. The aim of the present study was to investigate the genetic variability of the glycoprotein G gene in Tunisian RSV strains.Methodology. Nasopharyngeal aspirates were collected from infants hospitalized for LRTI in five Tunisian hospitals. All specimens were screened for RSV by a direct immunofluorescence assay (DIFA). To molecularly characterize Tunisian RSV strains, a phylogenetic analysis was conducted. Randomly selected positive samples were subjected to reverse transcription PCR amplifying the second hyper-variable region (HVR2) of the G gene.Results. Among a total of 1417 samples collected between 2015 and 2018, 394 (27.8 %) were positive for RSV by DIFA. Analysis of 61 randomly selected RSV strains revealed that group A RSV (78.7 %) predominated during the period of study as compared to group B RSV (21.3 %). The phylogenetic analysis showed that two genotypes of RSV-A were co-circulating: the ON1 genotype with a 72-nt duplication in HVR2 of the G gene was predominant (98.0 % of RSV-A strains), while one RSV-A strain clustered with the NA1 genotype (2.0 %). Concerning Tunisian group B RSV strains, all sequences contained a 60-nt insertion in HVR2 and a clustered BA10 genotype.Conclusion. These data suggest that RSV-A genotype ON1 and RSV-B genotype BA10, both with duplications in the G gene, were widely circulating in the Central coastal region of Tunisia between 2015 and 2018.

Transient neonatal diabetes mellitus and hypomethylation at additional imprinted loci: novel ZFP57 mutation and review on the literature.

AIM: 6q24-related transient neonatal diabetes mellitus (6q24-TNDM) is a rare imprinting disorder characterized by uncontrolled hyperglycemia during the first 6 months of life. The molecular etiology of 6q24-TNDM is attributable to overexpression of the paternally inherited PLAGL1 and HYMAI genes located on the 6q24 locus. One of these major defects is maternal loss of methylation (LOM) at 6q24. In addition, approximately 50% of TNDM patients that present LOM at 6q24 can also display hypomethylation at additional imprinted loci (multilocus imprinting disturbances, MLID). Interestingly, the majority of these patients carry mutations in the ZFP57 gene, a transcription factor required for the adequate maintenance of methylation during early embryonic development. METHODS: Methylation analysis of 6q24 and additional imprinted loci was carried out by MS-MLPA in a Tunisian male patient with clinical diagnosis of TNMD. For the same patient, mutation analysis of the ZFP57 gene was conducted by direct Sanger sequencing. RESULTS: We report a novel nonsense mutation (c.373C > T; p.R125*; ENST00000376883.1) at the ZFP57 gene causing TNDM-MLID and describe detailed phenotype/epigenotype analysis of TNMD patients carrying ZFP57 mutations. CONCLUSION: We provide additional support to the role of ZFP57 as a genetic determinant cause of MLID in patients with TNMD.

Demographic and seasonal characteristics of respiratory pathogens in neonates and infants aged 0 to 12 months in the Central-East region of Tunisia.

BACKGROUND: This study aimed to characterize the epidemiology of pathogenic respiratory agents in patients aged 0 to 12 months and hospitalized for acute respiratory infections in Tunisia between 2013 and 2014. METHODS: A total of 20 pathogens, including viruses, Mycoplasma pneumoniae, and Streptococcus pneumoniae, were detected using molecular sensitive assays, and their associations with the patient's demographic data and season were analyzed. RESULTS: Viral infectious agents were found in 449 (87.2%) of 515 specimens. Dual and multiple infectious agents were detected in 31.4% and 18.6% of the samples, respectively. Viral infection was predominant in the pediatric environment (90.8%, P < 0.001), male patients (88.0%), and spring (93.8%). Rhinovirus was the most detected virus (51.8%) followed by respiratory syncytial virus A/B (34.4%), coronavirus group (18.5%), adenovirus (17.9%), and parainfluenza viruses 1-4 (10.9%). Respiratory Syncytial virus A/B was significantly associated with gender (38.0% male cases vs 28.3% female cases, P = 0.02). Infections by Adenovirus, Bocavirus, and Metapneumovirus A/B increased with increasing age of patients (predominated cases aged 6-12 months, P < 0.001). S. pneumoniae was detected in 30.9% of th tested samples. In 18.2% of the negative viral infections, only S. pneumoniae was identified. CONCLUSION: A predominance of the rhinovirus infection was observed in this study. Coronavirus subtypes were described for the first time in Tunisia. The observed different pathogenic profiles across age groups could be helpful to avoid the misclassification of patients presenting with ARIs at the triage level when no standardized protocol is available. This study will provide clues for physicians informing decisions regarding preventive strategies and medication in Tunisia.

Transported neonates in Tunisia.

AIMS: To describe the transport of sick neonates to a tertiary care hospital and evaluate their condition at arrival and outcome. METHODS: A multicenter, prospective cohort study was performed in 7 NICUs in Tunisia from 1st april to 31 July 2015.Demographic parameters, transport details and clinical features at arrival were recorded. All neonates were followed up till discharge or death. RESULTS: A total of 239 consecutive neonates were enrolled in the study representing 5.7% of all admitted infants. Maternal risk factors were present in 26% of neonates admitted. Sex-ratio was 1.46. Preterm infants represented 24% of transported babies. Seventeen percent of neonates had severe respiratory distress and 10% had hemodynamic troubles. Referred hospital was not informed in 24% of cases. Regarding the transport mode, 113 newborns (47.5%) were transported in ambulance accompanied by a nurse. Documentation during transfert was present in 14% of cases. Five babies expired on arrival despite resuscitation.  Rate mortality was 8.4%. CONCLUSION: Transporting neonates in developing countries is a challenge. Organized transport services in Tunisia are not always available. So, in cases of at-risk pregnancy, it is safer to transport the mother prior to delivery than to transfer the sick baby after birth.

[Perinatal varicella: fetal and neonatal risks and management]. / La varicelle périnatale: risques et prise en charge fœtale et néonatale.

The occurrence of clinical varicella during pregnancy is rare but it may pose maternal and fetal risks. Perinatal maternal varicella may result in potentially severe neonatal varicella, especially when maternal eruptions occur between 5 days before and 2 days after delivery. We report eight cases of newborns of mothers with varicella in the peri-partum period in order to synthesize the current state of knowledge on the risk of contracting virus as well as to develop treatment protocol. We conducted a descriptive study at the Maternity and Neonatology Center, Sousse, over a period of 10 years. Eight newborns were included in the study. Prenatal diagnosis was made in 7 mothers. Only a woman developed varicella 3 days after delivery. Five newborns were symptomatic on admission. All newborns had typical varicella skin lesions, three of them had respiratory distress associated. Treatment was based on newborn isolation, local skin care and Acyclovir therapy. Patients evolution was favorable. The occurrence of varicella infection during pregnancy remains possible in the countries where vaccination is still not accessible to all. The risk of maternal and fetal complications justifies specific and well codified treatment.

Incidence of congenital heart disease in newborns after pulse oximetry screening introduction.

INTRODUCTION: Congenital heart defects are the most common congenital malformations in the newborn with an estimated incidence ranging between 6-9 ‰. In Tunisia, this incidence reaches 1.9 ‰. This can be explained by misdiagnosed cases. In fact, the diagnosis is based mainly on clinical examination which allows making the diagnosis only in 50 in 75 % of the cases. Several studies showed the interest of pulse oximetry oximeter in the screening of cyanogenic and duct dependent congenital heart diseases. The Objective of our work is to determine the incidence of congenital heart diseases screened by physical examination coupled with the measure of transcutaneous saturation Methods:  forward-looking and descriptive Study, concerning all the births of the central maternity of Sousse, during a period of 12 months. We have measured transcutaneous saturation of all the newborn children in association to routine physical, examination. This study aimed to screen congenital heart disease and then calculate their incidence. RESULTS: during the period of the study 10447 newborn children had been born in the central maternity of Sousse. Among whom, 26 had a congenital heart defect. The incidence of the neonatal cardiac malformations in our current study was found in 2.77 ‰ of alive births. It was about 1.1 ‰ of newborns in a similar study practised in 2009 (Chi2=76.2 et p<10-4). The heart disorder was diagnosed following the grip taking of the only percutaneous saturation in 5 newborn children and following the clinical examination in 21. CONCLUSION: the measure of the transcutaneous saturation in the first day of life is a little expensive and specific method for the early screening of the duct dependent cardiac malformations.

[Role of lymphatic scintigraphy and surgery in congenital chylothorax]. / Intérêt de la scintigraphie lymphatique et place de la chirurgie dans les chylothorax congénitaux.

Chylothorax is defined as accumulation of lymphatic fluid in the pleural space. Chylothorax in the neonatal period can be classified into three distinct categories: congenital chylothorax (CC), syndromic or malformative chylothorax (MC) and postoperative chylothorax (CO). Although rare, chylothorax is the most common cause of pleural effusions in the neonatal period. Making a positive diagnosis is easy by examination of the pleural fluid, but its mechanism and especially the integrity of thoracic duct and its collateral branches is sometimes difficult to determine. Lymphoscintigraphy is the test of choice in etipathogenic diagnosis. This diagnostic tool can be coupled, if possible, to SPECT-CT (single photon emission tomography / computed tomography) providing more specific anatomical informations. Tratment of chylothorax is based on the drainage of the pleural fluid, the suppression of dietary fats and on parenteral nutrition. Surgery is recommended in the case of medical treatment failure. We report the case of a newborn with unilateral chylothorax who did not respond to medical treatment. Lymphoscintigraphy allowed to diagnose etiopathogenic mechanism underlying chylothorax and therefore to direct surgical treatment.

[Cardiovascular manifestations of Kawasaki syndrome. Value of echocardiography in diagnosis and progression]. / Manifestations cardiovasculaires du syndrome de Kawasaki. Apport de l'échocardiographie dans le diagnostic et l'évolution.

Seven children with suspected Kawasaki disease were studied by echocardiogram. Coronary abnormalities occurred in all patients, associated with: thrombosis (2 patients) small pericardial effusion (2 patients) poor ventricular function (2 patients), moderate mitral regurgitation (2 patients). Patients received treatment with intravenous gamma globulin, aspirin, and anticoagulant. Echocardiogram abnormalities disappeared between 1 and 26 months after the onset of the disease; only persist coronary hyperechogenecity in 6 patients.