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S Sigaudy

Publications and source records attributed to S Sigaudy.

At least 19 recordsLinked to original sources

Genotype-phenotype correlation in Costello syndrome: HRAS mutation analysis in 43 cases.

BACKGROUND: Costello syndrome (CS) is a rare multiple congenital abnormality syndrome, associated with failure to thrive and developmental delay. One of the more distinctive features in childhood is the development of facial warts, often nasolabial and in other moist body surfaces. Individuals with CS have an increased risk of malignancy, suggested to be about 17%. Recently, mutations in the HRAS gene on chromosome 11p13.3 have been found to cause CS. METHODS: We report here the results of HRAS analysis in 43 individuals with a clinical diagnosis of CS. RESULTS: Mutations were found in 37 (86%) of patients. Analysis of parental DNA samples was possible in 16 cases for both parents and in three cases for one parent, and confirmed the mutations as de novo in all of these cases. Three novel mutations (G12C, G12E, and K117R) were found in five cases. CONCLUSIONS: These results confirm that CS is caused, in most cases, by heterozygous missense mutations in the proto-oncogene HRAS. Analysis of the major phenotypic features by mutation suggests a potential correlation between malignancy risk and genotype, which is highest for patients with an uncommon (G12A) substitution. These results confirm that mutation testing for HRAS is a reliable diagnostic test for CS.

Abnormalities, Multiple↗

Unusual phenotype with progressive vertebral fusion in a girl with an apparently balanced t(10;20)(p11;p13) translocation.

We report the case of a girl presenting with an unusual form of multiple joint fusion. Skeletal abnormalities consisted of radioulnar synostosis and vertebral fusions without any carpal, digital or tarsal involvement, and broad ribs and clavicles. Spinal X-rays were available from age 4 to 21, demonstrating that the spinal involvement was progressive and led to a complete anterior and lateral fusion of vertebrae. A complete sequencing of the NOGGIN gene failed to find any mutation. In addition, this girl was carrier of an apparently balanced reciprocal translocation t(10;20)(p11;p13). We investigated the role of the BMP2A gene as a potential candidate gene. Fluorescence in situ hybridization with YAC probes from chromosome 20 showed that the BMP2A gene was not disrupted by the translocation breakpoint.

Abnormalities, Multiple↗

Value of fetal autopsy after medical termination of pregnancy.

We carried out a retrospective study of 352 medical terminations of pregnancy (MTP) carried out in a large French administrative region over two consecutive years. We analysed the indications for MTP and then compared the prenatal ultrasound diagnosis with fetal autopsy findings in order to demonstrate the value of pathological examination of the fetus in prenatal diagnosis and genetic counselling as well as the need to check by autopsy the quality of ultrasound screening. Preliminary analysis of the indication for these MTP showed that in 69.9% ultrasound screening had been carried out, revealing mainly brain abnormalities (22.2%) and heart defects generally associated with chromosomal abnormalities (32.1%). Prenatal findings were in agreement with autopsy results, showing no false-positive prenatal diagnoses. However, in 7.9% of cases in which brain abnormalities were detected, confirmation was not possible at autopsy because of tissue autolysis, showing the need for optimal conditions of expulsion. In 35.8% of cases, confirmation of the diagnosis by autopsy was not useful for management but still added to medical knowledge and demonstrated to the mother the reality of the defects. In 50.9%, the autopsy findings were decisive for genetic counselling.

Aborted Fetus↗

[MRI and in utero ventriculomegaly].

Ventriculomegaly constitutes the major indication of fetal brain MRI. MRI is therefore of utmost importance to look for a cause through the depiction of criteria of malformations and through the definition of criteria of destructive lesions. Malformations and destructive lesions are the most common causes of ventricular dilatation. Some challenging points are worth mentioning in term of mechanism with the challenge of hydrocephalus (in term of increased in intracranial pressure) and of isolated ventriculomegaly. The image itself is also challenging since a similar image may be of different origin. In term of natural history of fetal brain injury an irregular, nodular aspect of the ventricular wall and/or the germinal matrix is often the only pathologic MRI finding that is known to be of clastic origin. In term of prognosis the challenge is represented by the isolated mild ventriculomegaly, the literature being quite confusing. The purpose of this review paper is to highlight the underlying mechanisms and pathophysiology of ventricular dilatation based on results from the literature as well as from personal experience.

Cerebral Ventricles↗

Value of fetal skeletal radiographs in the diagnosis of fetal death.

The aim of this study was to assess the value of fetal skeletal radiographs in determining the etiology of fetal death. A total of 1193 post-mortem fetal skeletal radiographs were analysed. Fetuses were classified into one of three groups (group I: abnormality diagnosed during pregnancy; group II: maternal pathology; group III: spontaneous abortion of pregnancy, IIIa before 26 weeks of gestation (WG), IIIb after 26 weeks of gestation). Face, supine and lateral skeletal views were performed. Skeletal abnormalities were detected in 33.9% of the fetuses, including 22.7% with minor abnormalities (abnormal rib number, no nasal bone ossification, amesophalangia or P2 hypoplasia of the fifth digit) and 14.5% with major abnormalities (other skeletal abnormalities). Among the fetuses with major abnormalities, 98.8% came from group I, 2.9% came from group II, 2.3% came from group IIIa and none came from group IIIb. Fetal skeletal radiographs are not useful in fetuses arising from spontaneous abortion of pregnancy without abnormality on ultrasound screening, abnormality clinical examination or in fetuses with prenatal diagnosis of chromosomal abnormality. This practice is valuable only if there is a multidisciplinary team, with all the participants (pathologists, radiologists, geneticists) knowledgeable about fetal pathology. In the absence of this multidisciplinary approach, it is easier to X-ray all fetuses to avoid misdiagnosis and the important consequences for genetic counselling.

Bone Diseases↗

[Outcome of infants with hypoplastic left heart syndrome diagnosed in utero].

The authors report the results of prenatal diagnosis of the hypoplastic left heart syndrome since 1998 in the University Hospitals of Marseille and Montpellier. Twenty-four prenatal diagnoses of this condition were made in mothers with a mean age of 29 (18 to 40 years) and after a mean term of 22 (18.5 to 33) weeks of amenorrhea. Seventeen therapeutic abortions were carried out and 7 neonates born after a mean term of 39 (28 to 40) weeks, were admitted to the paediatric intensive care unit. Two patients required ventilatory assistance with one early death. The other patients were stable after surgery. A Norwood (first stage) procedure was carried out in 6 neonates at a mean age of 5 (1 to 6) days. There was only one survivor (17%). Prenatal diagnosis of the hypoplastic left heart syndrome allows cardiac and extracardiac evaluation of foetuses with this condition. Therapeutic abortions may be proposed and was the commonest choice of the parents in this study. On the other hand, despite better management of neonates with this prenatal diagnosis, the poor prognosis of the Norwood first stage procedure is unchanged. A systematic search for a restriction of the foramen ovale on foetal echocardiography could optimise neonatal management of this problem.

Abortion, Therapeutic↗

[Bilateral vas deferens agenesis and inguinal hernia in a child. A rare, early presentation of cystic fibrosis].

UNLABELLED: Epididymal and ductal anomalies can be discovered incidentally during inguinal herniorraphy in children. The congenital bilateral absence of vas deferens is frequently associated with cystic fibrosis. CASE REPORT: This agenesia of vas deferens was detected in a 5-month-old boy who underwent an inguinal herniorraphy. Although the child did not present any symptoms, he actually presented cystic fibrosis: the sudoral test showed high levels of chloride (95 mmol/L) and an isolated homozygous delta F 508 deletion on the gene CFTR was evidenced on genetic investigations. CONCLUSION: The congenital bilateral absence of vas deferens is the most frequent anomaly of the male genital tract discovered in adults investigated for azoospermia. Relations with cystic fibrosis are well established but congenital bilateral absence of vas deferens discovered during infancy is an exceptional situation that requires genetic investigations to show evidence of a likely underlying cystic fibrosis.

Cystic Fibrosis↗

Wolf-Hirschhorn (4P-) syndrome in adults.

Wolf-Hirschhorn syndrome (WHS) or 4p-deletion syndrome has been extensively described in children. Knowledge on adult WHS patients is still limited due to the small number of published cases. We present 4 adults and review the literature. The phenotype of adult WHS is in general similar to that of childhood WHS. Growth retardation, microcephaly and mental retardation are the rule in both adults and children. Facial dysmorphism also remains similar. The main difference lies in the absence of serious internal (cardiac) abnormalities in adult WHS. Mental retardation ranges from moderate to severe. The nosological overlap between WHS and Pitt-Rogers-Danks syndrome (PRDS) is discussed. More extensive data on adult WHS are needed for appropriate counselling of families with affected young children.

Abnormalities, Multiple↗

Costello syndrome: report of six patients including one with an embryonal rhabdomyosarcoma.

UNLABELLED: Costello syndrome was first described in 1971. Besides papillomata, which were part of the initial description, patients tends to develop benign tumours of ectodermal origin. Aetiology is yet unknown but it is supposed to be the result of a sporadic dominant mutation. We report six patients with typical clinical findings and emphasise the importance of cardiac manifestations and the tendency to develop tumours. One patient developed an embryonal rhabdomyosarcoma, the occurrence of which has been reported twice before in patients with Costello syndrome. CONCLUSION: There might be a causal link between the development of rare tumours and this genetic disorder which may provide a new clue concerning the identification of the gene involved in Costello syndrome.

Cardiomyopathy, Hypertrophic↗

[Pigmentosum retinis and tubulo-interstitial nephronophtisis in Sensenbrenner syndrome: a case report].

PURPOSE: Sensenbrenner syndrome or cranio-ectodermal dysplasia is an extremely rare autosomal recessive condition (12 cases reported in literature). Our observation shows the possibility of both ocular and renal involvement associated with cranio-ectodermal abnormalities. PATIENTS: and method:We report the case of a girl who presented a typical cranio-ectodermal syndrome with dolicocephaly, short thorax, short limbs, short fingers and teeth abnormalities. At five years, she was found to have pigmentosum retinitis with amblyopy and moderate hyperopia. A chronic renal failure with uncontrollable hypertension underwent a cadaveric-donor transplantation at the age of six years. RESULTS: Two years later, the pigmentosum retinitis was stable. The kidney histology revealed a tubulo-interstitial nephronophtisis. The molecular analysis of the NPH 1 locus, which was associated with nephronophtisis, was negative. DISCUSSION: Our observation and two recent publications have in common ocular and renal abnormalities associated with cranio-ectodermal dysplasia. The underlying genetic defect would involve not only morphogenesis but also development and maturation of organs as eye and kidney. Sensenbrenner syndrome would thus be similar to certain disorders affecting the eye, kidney, skeleton and ectodermal structures such as the EEM, Senior-Loken, Mainzer-Saldino, and Jeune syndromes. CONCLUSION: The retinal dystrophy falls within the spectrum of clinical and genetic forms of pigmentosum retinitis. Our observation would confirm possible links between Sensenbrenner syndrome and oculorenal syndromes.

Abnormalities, Multiple↗

Microcephalic osteodysplastic primordial dwarfism Taybi-Linder type: report of four cases and review of the literature.

Microcephalic and osteodysplastic primordial dwarfism (MODP) types I, II, and III were defined by Majewski et al. in 1982. This group of syndromes was characterized by intrauterine growth retardation, microcephaly, and typical facial appearance with prominent nose and micrognathia. Type II was clearly different, both clinically and radiologically, whereas types I and III shared manifestations. Distinction between the latter two was established on the basis of subtle radiological differences. In 1967, Taybi and Linder described another syndrome with microcephalic congenital dwarfism. There is a consensus that MODP type I and III and Taybi-Linder cephaloskeletal dysplasia represent the same disorder. We report on four patients with MODP type Taybi-Linder syndromes, two of whom were born to unrelated but consanguineous parents, while the other two were sibs. Second-trimester prenatal detection by ultrasonography was possible in one case. Consanguinity in two cases and recurrence among sibs are consistent with autosomal recessive inheritance.

Abnormalities, Multiple↗

CHARGE syndrome: report of 47 cases and review.

The acronym CHARGE refers to a syndrome of unknown cause. Here we report on 47 CHARGE patients evaluated for the frequency of major anomalies, namely coloboma (79%), heart malformation (85%), choanal atresia (57%), growth and/or mental retardation (100%), genital anomalies (34%), ear anomalies (91%), and/or deafness (62%). In addition, we comment on anomalies observed very frequently in neonates and infants with the CHARGE syndrome, including, minor facial anomalies, neonatal brain stem dysfunction with cranial nerve palsy, and, mostly, internal ear anomalies such as semicircular canal hypoplasia that were found in each patient that could be tested. We propose several criteria for poor survival including male gender, central nervous system and/or oesophageal malformations, and bilateral choanal atresia. No predictive factor regarding developmental prognosis could be identified in our series. A significantly higher mean paternal age at conception together with concordance in monozygotic twins and the existence of rare familial cases support the role of genetic factors such as de novo mutation of a dominant gene or subtle sub-microscopic chromosome rearrangement. Finally, the combination of malformations in CHARGE syndrome strongly supports the view that this multiple congenital anomalies/mental retardation syndrome is a polytopic developmental field defect involving the neural tube and the neural crests cells.

Abnormalities, Multiple↗

Costello syndrome.

Costello syndrome is characterised by postnatal growth deficiency, coarse facies, redundant skin on the neck, palms, soles, and fingers, dark skin, acanthosis nigricans, and papillomata. The natural history evolves in two phases, a severe failure to thrive during the first months contrasting with a normal weight gain in later life. Cardiomyopathy is frequent but other visceral involvement is rare. Mild to moderate mental retardation is usual and most patients exhibit a characteristic sociable and friendly personality. The pathogenesis and molecular basis of the syndrome are unknown and the diagnosis is reliant on clinical expertise. Papillomata represent the most characteristic manifestation but may arise late in life. The peculiar course of the disease, the typical facies, and the ectodermal involvement with loose and hyperpigmented skin are characteristic enough to allow an early diagnosis. Most cases have been sporadic, suggesting de novo dominant mutations.

Abnormalities, Multiple↗