Orofaciodigital syndrome with cerebral dysgenesis.

Orofaciodigital syndromes (OFD) are a group of diseases classified according to the phenotype and the mode of inheritance. We report on a fetus presenting with some features of the OFDs but with additional global cerebral dysgenesis. Ultrasonography at 19 weeks of pregnancy disclosed hypoplasia of the cerebral hemispheres with a large intrahemispheric cyst, as well as dysmorphic facial features and brachy-syndactyly IV-V. Fetal brain MRI confirmed these features and disclosed additional morphological anomalies: Agenesis of the vermis, complete agenesis of the corpus callosum, pachygyria of the left hemisphere. Pathological examination showed a disproportionate fetus with large head and short limbs. Dysmorphic features included hypertelorism, broad nasal root, long philtrum, severe micrognathia, microstomia, cleft palate, and lobulated tongue. Radiographs showed distal malformations of the four limbs. Neuropathological examination showed a severe disturbance of the architecture of both hemispheres, more severe on the right side, with four cystic structures located between the hemispheres. Olfactory stalks, mammillary bodies, and midline structures were absent. Cerebellum and brainstem were hypoplastic. On the right hemisphere as on most part of the left one, microscopic findings displayed a complete disruption of the developing mantle with disturbance of the neuronal migration. The present fetus fulfilled the diagnosis of OFD syndrome: Dysmorphic features, cleft palate and lobulate tongue and polysyndactylies of the feet and hands. The cerebral involvement would make it closer to OFD type VI, but brain malformations were far more severe in the present case, with complex and generalized cortical dysgenesis, evoking a disturbance occurring at a very early stage of the embryogenesis.

Focal sonographic periventricular pattern associated with mild ventriculomegaly in foetal cytomegalic infection revealing cytomegalic encephalitis in the third trimester of pregnancy.

OBJECTIVES: To report focal sonographic periventricular pattern related to residual germinal matrix lesions in foetal cytomegalic infection in association with mild ventriculomegaly seen during the third trimester of pregnancy correlating with neuropathological findings of encephalitis. METHODS: We reviewed prenatal cerebral sonographic examination performed in three patients, during the third trimester of pregnancy, looking for either late 'isolated' ventriculomegaly (n = 2) or sonographic follow-up of cerebral structures following a known primary CMV infection in the early stage of pregnancy (n = 1). In cases of isolated ventriculomegaly, serological examination identified prenatal CMV infection. Magnetic resonance imaging (MRI) was performed in all cases. Imaging findings were compared with those following neuropathological examination. RESULTS: In all cases, ultrasound examination revealed an abnormal focal symmetrical bilateral periventricular pattern on the mid-lateral border of the lateral ventricles, including a mainly hyperechogenic lesion containing a few microcysts (case 1), a mixture of echogenic tissue and cysts (case 2) and mainly cystic areas (case 3). No alteration of cephalic biometry was noted. Neuropathological examination correlated these abnormal areas with lesions of the residual germinal matrix including inflammation and necrosis, but revealed also an extensive inflammatory process of the whole foetal brain. CONCLUSIONS: This focal sonographic periventricular pattern associated with mild ventriculomegaly without any abnormalities of the cerebral and cerebellar organogenesis nor cephalic biometry alteration in the third trimester of pregnancy should be considered as a marker of encephalitis following CMV infection of the foetal brain.

Campomelic acampomelic dysplasia presenting with increased nuchal translucency in the first trimester.

This is the first report of a fetus affected with campomelic acampomelic dysplasia presenting with increased nuchal translucency. Ultrasonography at 13 weeks of amenorrhea showed a nuchal translucency 5.6 mm thick. The karyotype performed on amniotic fluid cells was normal (46,XY). Ultrasonography at 22 weeks revealed a normal femoral length and female genitalia. A second amniocentesis was performed to confirm the karyotype and for dosage of steroid hormones. Testosterone dosage was low, corresponding to a female fetus. Ultrasonography at 32 weeks showed growth retardation of the long bones (< 3rd centile) that were not curved. A severe malformation syndrome was suspected and the pregnancy was terminated at 33 weeks. The fetus displayed macrocephaly, facial dysmorphism and female external genitalia. X ray showed straight and thickened long bones, hypoplastic scapulae and moderate platyspondyly. In view of the association of sex reversal, hypoplasia of the scapulae, and the presence of straight long bones, campomelic acampomelic dysplasia was suspected and confirmed by the finding of a SOX9 mutation. This case shows the importance of a careful echographic survey in a fetus with a nuchal translucency > 4 mm, especially if there is discordance between phenotypic and genotypic sex, since growth retardation may occur later during the pregnancy.

The spectrum of type III lissencephaly: a clinicopathological update.

A third type of lissencephaly that does not fufil diagnostic criteria of type I ("classical") and type II ("cobblestone") lissencephaly was described by our group as a new entity identified as OMIM 601160. This lethal familial syndrome comprises micrencephaly/lissencephaly and a spectrum of abnormalities lined to a severe fetal akinesia deformation sequence. Neuropathological findings suggest severe neurodegeneration leading to a marked neuronal dropout of the entire central nervous system and atrophy. Similar neuropathological findings have been described in the Neu-Laxova syndrome (NLS), an apparently different lethal malformation syndrome. Neuropathological similarities between OMIM 601160 and NLS raise the question of clinicopathological variability and genetic heterogeneity of type III lissencephaly. To answer this question, we compared our clinicopathological findings in a series of fetuses with OMIM 601160 to pathological data reported in NLS. In the study, 5 unrelated families with 7 affected fetuses were included. Interestingly, we found striking clinicopathological similarities between OMIM 601160 and NLS, which may represent a variability of a single neurodegenerative disease with early prenatal onset. Molecular studies in multiplex families defined through detailed clinicopathological screening are needed to clarify the distinction, if any, between these two entities.

Molecular screening of the TGIF gene in holoprosencephaly: identification of two novel mutations.

Holoprosencephaly (HPE) is the most common severe brain anomaly in humans, which results from incomplete cleavage of the forebrain during early embryogenesis. The aetiology of HPE is very heterogeneous. Among the genetic factors, TGIF ( TG-interacting factor), which codes for a transcription factor modulating the signalling pathway of TGF-beta, was previously implicated. We investigated 127 HPE probands by sequencing their TGIF gene and identified the first nonsense mutation reported so far and also a novel missense mutation, in two families that presented a large range of disease severity. The low number of mutations in TGIF suggests that this gene has no major contribution to the aetiology of HPE and our study confirms the wide clinical heterogeneity of the disease.