Audiological phenotyping evaluation in KBG syndrome: Description of a multicenter review.

OBJECTIVES: Our objective was to reinforce clinical knowledge of hearing impairment in KBG syndrome. KBG syndrome is a rare genetic disorder due to monoallelic pathogenic variations of ANKRD11.The typical phenotype includes facial dysmorphism, costal and spinal malformation and developmental delay. Hearing loss in KBG patients has been reported for many years, but no study has evaluated audiological phenotyping from a clinical and an anatomical point of view. METHODS: This French multicenter study included 32 KBG patients with retrospective collection of data on audiological features, ear imaging and genetic investigations. RESULTS: We identified a typical audiological profil in KBG syndrome: conductive (71%), bilateral (81%), mild to moderate (84%) and stable (69%) hearing loss, with some audiological heterogeneity. Among patients with an abnormality on CT imaging (55%), ossicular chain impairment (67%), fixation of the stapes footplate (33%) and inner-ear malformations (33%) were the most common abnormalities. CONCLUSION: We recommend a complete audiological and radiological evaluation and an ENT-follow up in all patients presenting with KBG Syndrome. Imaging evaluation is necessary to determine the nature of lesions in the middle and inner ear.

Gnathodiaphyseal dysplasia with a novel R597I mutation of ANO5: Mandibular reconstruction strategies.

Gnathodiaphyseal Dysplasia (GDD) is a rare, often misdiagnosed, autosomal-dominant disorder due to point mutations in the ANO5 gene. GDD combines craniofacial fibro-osseous lesions, dental loss and progressive curvature and cortical thickening of long bones and vertebra, causing pathological fractures. Diagnosis is based on bone pathology and mutation screening. Here we report three GDD cases within a single family with a novel ANO5 mutation: c.1790 G > T (p.Arg597Ile, i.e. R597I) on exon 16. Microsurgical mandibular reconstructions were performed in the three cases. We reviewed the literature on jaw reconstruction in this condition and discussed the challenges of craniofacial reconstruction in GDD due to the diffuse bone anomalies affecting potential flap donor zones and a specific risk for jawbone osteomyelitis.

Chondrodysplasia with multiple dislocations: comprehensive study of a series of 30 cases.

The group of chondrodysplasia with multiple dislocations includes several entities, characterized by short stature, dislocation of large joints, hand and/or vertebral anomalies. Other features, such as epiphyseal or metaphyseal changes, cleft palate, intellectual disability are also often part of the phenotype. In addition, several conditions with overlapping features are related to this group and broaden the spectrum. The majority of these disorders have been linked to pathogenic variants in genes encoding proteins implicated in the synthesis or sulfation of proteoglycans (PG). In a series of 30 patients with multiple dislocations, we have performed exome sequencing and subsequent targeted analysis of 15 genes, implicated in chondrodysplasia with multiple dislocations, and related conditions. We have identified causative pathogenic variants in 60% of patients (18/30); when a clinical diagnosis was suspected, this was molecularly confirmed in 53% of cases. Forty percent of patients remain without molecular etiology. Pathogenic variants in genes implicated in PG synthesis are of major importance in chondrodysplasia with multiple dislocations and related conditions. The combination of hand features, growth failure severity, radiological aspects of long bones and of vertebrae allowed discrimination among the different conditions. We propose key diagnostic clues to the clinician.

[Craniofacial strategy for syndromic craniosynostosis]. / Stratégie craniofaciale pour les faciocraniosténoses.

The complexity of treatment of faciocraniosynostosis justifies the treatment in a reference center for rare diseases. The growth disturbances in the skull and face being variable according to the type of mutation in the FGFr (Crouzon, Pfeiffer, Apert), the strategy is adapted to the phenotype according to the following principles: posterior expansion with or without distraction around 6 months to limit the descent of the cerebellum tonsils and to prevent the turricephalic development; fronto-facial monobloc advancement with internal distraction around the age of 18 months in case of severe exorbitism or breathing impairment. The dissociated strategy (fronto-orbital advancement first, followed by facial osteotomy of Le Fort 3 type). The growing evolution dictates the sequence of subsequent surgeries according to the monitoring of intracranial pressure by fundus examination and of the respiration by polysomnography. Le Fort 3 and transversal maxillary distraction may be repeated if necessary. Orthognathic surgery is almost always compulsory after the age of 14, before the aesthetic refinements which can be undertaken ultimately (rhinoplasty, genioplasty, canthopexies, fat grafting…).

[GACI syndrome: a case report with a neonatal beginning]. / Le syndrome GACI : à propos d'une observation à début néonatal.

GACI (generalized arterial calcification of infancy) is a rare autosomal recessive disorder characterized by arterial and periarticular calcifications. Most children die in the first months of life of cardiovascular complications. Hypophosphatemic rickets (HR) resistant to medical treatment may complete the phenotype and is associated with a milder phenotype. This report discusses the case of a girl who presented neonatal ectopic periarticular calcifications with spontaneous regression, and then at the age of 3 years developed HR. There was no clinical improvement after treatment with calcitriol and phosphate, and correction of alkaline phosphatase induced the recurrence of periarticular and tissular calcifications : the treatment was reduced and the bone distortion treated by surgery. GACI diagnosis was confirmed by genetic analysis. At the age of 4.5 years, she developed a retinal abnormality and decreased radial pulse: these clinical signs are usually observed in pseudoxanthoma elasticum (PXE). It is now established that GACI and PXE belong to the same entity characterized by arterial and tissular calcifications of which this original case report is an illustration.

Unexpected high frequency of skeletal dysplasia in idiopathic short stature and small for gestational age patients.

OBJECTIVE: To assess the prevalence of skeletal dysplasias (SDs) in patients with idiopathic short stature (ISS) or small for gestational age (SGA) status. SETTING: Rare Endocrine/Growth Diseases Center in Paris, France. DESIGN: A prospective study on consecutive patients with ISS and SGA enrolled from 2004 to 2009. METHOD: We used a standardized workup to classify patients into well-established diagnostic categories. Of 713 patients with ISS (n=417) or SGA status (n=296), 50.9% underwent a skeletal survey. We chose patients labeled normal or with a prepubertal slowdown of growth as a comparison group. RESULTS: Diagnoses were ISS (16.9%), SGA (13.5%), normal growth (24.5%), transient growth rate slowing (17.3%), endocrine dysfunction (12%), genetic syndrome (8.9%), chronic disease (5.1%), and known SD (1.8%). SD was found in 20.9% of SGA and 21.8% ISS patients and in only 13.2% in our comparison group. SD prevalence was significantly higher in the ISS group than in the comparison group, especially (50%) for patients having at least one parent whose height was <-2 SDS. Dyschondrosteosis and hypochondroplasia were the most frequently identified SD, and genetic anomaly was found in 61.5 and 30% respectively. Subtle SD was found equally in the three groups and require long-term growth follow-up to evaluate the impact on final height. CONCLUSION: SD may explain more than 20% of cases of growth retardation ascribed to ISS or SGA, and this proportion is higher when parental height is <-2 SDS. A skeletal survey should be obtained in patients with delayed growth in a context of ISS or SGA.

Osteopathia striata congenita with cranial sclerosis and intellectual disability due to contiguous gene deletions involving the WTX locus.

Osteopathia striata congenita with cranial sclerosis (OSCS) is a skeletal dysplasia caused by germline deletions of or truncating point mutations in the X-linked gene WTX (FAM123B, AMER1). Females present with longitudinal striations of sclerotic bone along the long axis of long bones and cranial sclerosis, with a high prevalence of cleft palate and hearing loss. Intellectual disability or neurodevelopmental delay is not observed in females with point mutations in WTX leading to OSCS. One female has been described with a deletion spanning multiple neighbouring genes suggesting that deletion of some neighbouring loci may result in abnormal neurodevelopment. In this cohort of 13 females with OSCS resulting from deletions of WTX, a relationship is observed where deletion of ARHGEF9 and/or MTMR8 in conjunction with WTX results in an additional neurodevelopmental phenotype whereas deletion of ASB12 along with WTX is associated with a good neurodevelopmental prognosis.

[Prenatal symptoms and diagnosis of inherited metabolic diseases]. / Maladies héréditaires du métabolisme : signes anténatals et diagnostic biologique.

Inherited metabolic diseases are mostly due to enzyme deficiency in one of numerous metabolic pathways, leading to absence of a compound downstream from and the accumulation of a compound upstream from the deficient metabolite(s). Diseases of intoxication by proteins (aminoacidopathies, organic acidurias, urea cycle defects) and by sugars (galactosemia, fructosemia) usually do not give prenatal symptoms since mothers protect their fetuses from pathological metabolite accumulation. A well-known exception is hypoplasia of corpus callosum, as is sometimes observed in nonketotic hyperglycinemia and sulfite oxidase deficiency. Conversely, women with phenylketonuria "poison" their fetus if they are not treated (spontaneous abortions, intrauterine growth restriction [IUGR], cardiac malformations, and brain disease). Amino acid synthesis defects can lead to prenatal symptoms: microcephaly in serine deficiency (detectable by amino acid analysis in fetal cord blood), and brain malformations in glutamine synthetase deficiency. Impaired folate metabolism is involved in a large fraction of neurodevelopmental defects referred to as spina bifida, yet the underlying genetic component(s) are largely unknown. Energy metabolism diseases caused by defects in the synthesis or utilization of relevant metabolites lead to organ dysfunctions or malformations, but prenatal diagnosis is usually impossible unless genetic analysis can rely on a previously affected child in the family. A somewhat intermediate condition is defects of mitochondrial beta-oxidation of fatty acids, as they may sometimes be symptomatic prenatally (notably the HELLP syndrome or other presentations), and in this case, organic acid and acylcarnitine analysis in amniotic fluid can be informative in the absence of an index case. In contrast, complex molecule diseases commonly give prenatal symptoms that may permit the diagnosis even in the absence of index cases: hydrops fetalis and skeletal anomalies in lysosomal storage diseases, hydrops fetalis in congenital disorders of glycosylation (CDG) and transaldolase deficiency, brain malformations in O-glycosylation defects, brain malformations, kidney cysts and skeletal anomalies in peroxysomal diseases (Zellweger syndrome), syndactyly, genitalia malformations, and IUGR in Smith-Lemli-Opitz (SLO) syndrome. Although many metabolic disorders show biochemical abnormalities during fetal development that are informative for prenatal diagnosis, only a fraction of them are clinically/sonographically symptomatic before birth, thus allowing for prenatal diagnosis in the absence of an index case, i.e., serine deficiency, some fatty acid beta-oxidation defects, transaldolase deficiency, lysosomal diseases, CDG, Zellweger syndrome, and SLO syndrome.

Stüve-Wiedemann syndrome: long-term follow-up and genetic heterogeneity.

Stüve-Wiedemann syndrome (SWS, OMIM 601559) is a severe autosomal recessive condition caused by mutations in the leukemia inhibitory receptor (LIFR) gene. The main characteristic features are bowing of the long bones, neonatal respiratory distress, swallowing/sucking difficulties and dysautonomia symptoms including temperature instability often leading to death in the first years of life. We report here four patients with SWS who have survived beyond 36 months of age with no LIFR mutation. These patients have been compared with six unreported SWS survivors carrying null LIFR mutations. We provide evidence of clinical homogeneity of the syndrome in spite of the genetic heterogeneity.

Congenital skin pedicles with or without amniotic band sequence: Extending the human phenotype resembling mouse disorganization.

Congenital skin pedicles are very rare and usually described in association with multiple congenital anomalies. Here, we report on six patients with congenital pedicle skin hamartomatous lesions. Two patients showed a single skin pedicle lesion, one of whom was also shown to have 22q11.2 microdeletion syndrome, and four patients also had severe limb anomalies for which they were originally diagnosed with amniotic band sequence (ABS). We propose that all these infants instead show various forms of the phenotype resembling disorganization in the mouse. This article supports previous reports suggesting that "Disorganization-like" mutations may cause cases with apparent ABS. Owing to these reports, we propose the hypothesis that hamartomatous skin pedicles and "ABS plus" are different phenotypes of the human disorder resembling disorganization.

[Epidemiology and prognosis of childhood cancers in Dakar, Senegal]. / Epidémiologie et pronostic des affections malignes de l'enfant à Dakar, Sénégal.

Childhood cancer has often been considered as a problem mainly affecting industrialized countries. In reality more than half of cases occur in developing countries where management and diagnosis are major issues. This retrospective study includes 130 children (0.3% of admissions) between the ages of 0 and 15 years hospitalized for malignant disease at the Principal Hospital in Dakar, Senegal between January 1, 1990 and December 31, 2000. Mean age was 97 months and M/F sex ratio was 1.2. Mean delay for admission was 3 months. The five most frequent cancers, accounting for 75% of cases, were leukemia (n = 28), lymphoma (n = 21), nephroblastoma (n = 21), retinoblastoma (n = 16) and osteochondrosarcoma (n = 10). Treatment was completed in 18% of cases. Half of patient were lost from follow-up. The cure rate was 10% overall and 50% for patients receiving complete treatment. The highest cure rate was achieved for nephroblastoma, i.e., 58% of cases treated. Management of childhood cancer in Africa is confronted with numerous problems, namely, paucity of specialized staff, absence of expert centers, shortage of anticancer drugs, lack of financial resources, and delay in treatment. These factors associated with frequent malnutrition and recurrent infectious diseases, greatly lower cure rates in comparison with industrialized countries.

[Escherichia coli meningitis in a 16-month old infant revealing a posterior fossa epidermoid cyst]. / Méningite à Escherichia coli chez un nourrisson de 16 mois révélant un kyste épidermoïde de la fosse postérieure.

UNLABELLED: Meningitis due to Escherichia coli is rare, and generally observed in very particular circumstances, such as neonatal period, anatomical anomalies or in immune-deficient patients. CASE REPORT: A 16-month-old male infant was admitted for acute meningitis. E coli was detected in the cerebro-spinal fluid (CSF). As appropriate antibiotic treatment proved inefficient, a cerebral computerised tomography (CT) scan was performed, revealing an epidermoid cyst of the posterior fossa. The cyst was resected after CSF sterilisation. Postoperative recovery was satisfactory. CONCLUSION: When an unusual bacterial species such as E coli is detected in CSF, the authors suggest consideration of a cutaneous or ETN focus, or a congenital malformation with communication between cutaneous and meningeal structures.