Three-dimensional helical computed tomography in prenatal diagnosis of fetal skeletal dysplasia

OBJECTIVES

(1) To study the use and diagnostic value, as a complement to ultrasound, of helical computed tomography (helical CT) to differentiate normal fetuses from cases of skeletal dysplasia; (2) to define the most relevant indications for helical CT; and (3) to evaluate its diagnostic performance with respect to radiological criteria considered discriminatory.

METHODS

This was a retrospective study from 2005 to 2008 in 67 pregnant women who underwent helical CT after 26 weeks of gestation for suspected fetal skeletal dysplasia due to fetal shortened long bones on ultrasound (≤ 10(th) percentile), either alone or associated with other bone abnormalities. The results were compared with pediatric examinations in 41 cases and with fetal autopsy findings after elective termination of pregnancy in the others.

RESULTS

Helical CT had a sensitivity of 82%, specificity of 91% and positive and negative predictive values of 90% and 83%, respectively, for diagnosis of fetal skeletal dysplasia. An etiological diagnosis that had not been suspected at ultrasound was specified in 15% of cases and diagnoses suspected at ultrasound were confirmed in 24% and discounted in 43% of cases. The prevalence of skeletal dysplasia was increased in cases of micromelia < 3(rd) percentile or if there was a combination of bone signs. Helical CT showed 69% sensitivity in identifying individual predefined pathological bone signs which were confirmed on fetal autopsy findings.

CONCLUSION

Helical CT is a key examination, in combination with ultrasound, in the diagnosis of fetal skeletal dysplasia from 26 weeks of gestation. It should be reserved for cases with severe micromelia below the 3(rd) percentile and for those with micromelia ≤ 10(th) percentile associated with another bone sign. A checklist of discriminatory signs is proposed.

Epilepsy and primary cerebral tumours

Although the association of epilepsy with cerebral tumours is well recognized, the reported incidence of seizures and relationship to tumour pathology varies significantly. This study assessed retrospectively the incidence of seizures, relationship to tumour pathology, natural history of epilepsy and prognostic significance of presentation with a seizure in 120 consecutive adults with histologically proven primary cerebral hemisphere tumours including meningiomas. 52% had a seizure and most were at presentation. Seizures were more common with anaplastic astrocytoma (AA) (18 23 ) than glioblastoma multiforme (21 56 ) (p = 0.001) and seizure occurrence was associated with cortical invasion. 52% of meningioma patients had a seizure. Seizures recurred in 34%, more frequently with glioma (19 of 46) than meningioma (1 of 15) (p < 0.05). Patients with AA presenting with a seizure had a longer survival (28 months) than patients without seizure (8 months) (p = 0.05 one sided). In conclusion, seizures are a common complication of cerebral tumours, usually at presentation and correlate with tumour pathology. A seizure at presentation in AA correlates with longer survival.

Rapidly progressive Whipple's disease of the central nervous system

We describe a patient with rapidly progressive Whipple's disease confined to the central nervous system (CNS). The diagnosis was made pre-mortem following stereotactic and open brain biopsis and confirmed at autopsy. Despite appropriate antibiotic treatment, the disease ran a fulminant course to death after nine weeks.

[Prenatal diagnosis of cleft lip with or without cleft palate: retrospective study and review]

OBJECTIVES

To evaluate the management of prenatally diagnosed cleft lip with or without cleft palate and the immediate postnatal outcome.

MATERIAL AND METHODS

Retrospective study of all cases of cleft lip with or without cleft palate referred to our fetal medicine unit, between January 2005 and January 2011. The anatomical type of cleft, associated malformations, and the postnatal outcome were reviewed.

RESULTS

Forty-three cases of fetal cleft lip with or without cleft palate were reviewed. The mean gestational age at diagnosis was 24 weeks ± 4. The postnatal distribution of clefts was: 30 cleft lip and palate (70%) and 13 cleft lip (30%). The prenatal diagnosis of the cleft type was exact in 27 cases (62.8%). Nine cases had associated anomalies (21%), detected prenatally in three cases (37.5%). There was no karyotypical abnormality. Six pregnancies were terminated (14%). The immediate postnatal outcome was comparable with unselected newborns.

CONCLUSION

The prenatal diagnosis of cleft lip with or without cleft palate is correct, with two thirds of exact diagnoses. Large clefts palate are the best detected. Associated malformations cannot always be diagnosed by prenatal ultrasound, but have to be searched for because they modify the fetal outcome.

Intragenic rearrangements in LARGE and POMGNT1 genes in severe dystroglycanopathies

Dystroglycanopathies are a heterogeneous group of muscular dystrophies with autosomal recessive inheritance characterized by abnormal glycosylation of alpha-dystroglycan. The most severe phenotypes are Walker-Warburg Syndrome (WWS) and muscle-eye-brain disease (MEB) presenting with lissencephaly type II (LIS II) and in which muscular dystrophy is associated with mental retardation and eye abnormalities. To date, six distinct genes, POMT1, POMT2, POMGNT1, FKTN, FKRP, LARGE and recently in one case DPM3, have been shown to be involved in dystroglycanopathies. Genomic sequencing alone is still frequently used for diagnosis purpose, not allowing detection of intragenic rearrangements at the heterozygous state contrarily to RNA analysis, quantitative PCR and CGH array analysis. These latter methods enabled us to identify four new intragenic rearrangements in the LARGE gene in three fetuses with WWS, born to two unrelated families: deletion of exons 9-10 and duplication of introns 1-4 for the first family and deletion of exons 4 and 7 for the second one; and a deletion of the last six exons of the POMGNT1 gene in two unrelated MEB patients. Genomic dosage studies using emerging tools such as CGH array should be included in routine molecular analysis of dystroglycanopathies, not only for the screening of the LARGE gene in which this kind of mutation seems to be more frequent than point mutations, but also for the other involved genes, especially in severe clinical cases.

[Genetic testing in the context of the revision of the French law on bioethics]

This article focuses on six questions raised by genetic testing in human: (1) the use of genetic tests, (2) information given to relatives of patients affected with genetic disorders, (3) prenatal and preimplantatory diagnosis for late onset genetic diseases and the use of pangenomic tests in prenatal diagnosis, (4) direct-to-consumer genetic testing, (5) population screening in the age of genomic medicine and (6) incidental findings when genetic testing are used.

412 OVARIAN RESPONSE IN ALPACAS (VICUGNA PACOS) TO SUPERSTIMULATORY TREATMENT WITH FOLLICLE-STIMULATING HORMONE AND EQUINE CHORIONIC GONADOTROPIN

The objective of this study was to evaluate the ovarian response in alpacas to superstimulatory treatment with FSH and eCG. Alpacas females (n = 49) were examined daily by transrectal ultrasonography using a 7.5-MHz linear-array transducer (Aloka SSD500, Tokyo, Japan) to determine ovarian follicular dynamics. Alpacas (n =41) were selected when a growing follicle ≥7 mm in diameter was detected and were given an i.m. injection of 4 μg of buserelin (Conceptal®, Intervet, Millsboro, MD, USA) on Day 0 (i.e. beginning of treatment). On Day 2, alpacas were assigned to 1 of the following 2 treatments: (1) the FSH group (n = 21), which received a total dose of 200 mg NIH-FSH-P1 of pFSH (Folltropin®-V, Bioniche Animal Health Inc., Belleville, Ontario, Canada) in decreasing dosages of 52, 48, 40, 32, and 28 mg divided in twice-daily i.m. injections for 5 days; and (2) the eCG group (n = 20), which received a single dose of 750 IU of eCG (Folligon®, Intervet, Millsboro, MD, USA). Animals received an i.m. dose of 0.150 mg of triapost (PGF; Iliren, Intervet, Millsboro, MD, USA) on Day 6. On Day 7, ovaries of all alpacas were examined by transrectal ultrasonography, followed by mating and embryo collection on Day 14. Data were analyzed by ANOVA. The mean number of follicles <7 mm in diameter was 5.8 ± 1.0 and 3.2 ± 0.9 for those treated with FSH and eCG, respectively (NS). The number of follicles 7 to 13 mm in diameter was 5.8 ± 1.5 and 9.7 ± 1.2 for the FSH and eCG groups, respectively (P < 0.05). The number of follicles >13 mm in diameter was 0.3 ± 0.4 and 1.0 ± 0.3 for the FSH and eCG groups, respectively (NS). The mean (± SD) follicle diameter was 8.3 ± 0.3 and 9.0 ± 0.2 for the FSH and eCG groups, respectively (NS). The mean (± SD) number of CL was 6.0 ± 1.9 and 8.7 ± 2.3 for the FSH and eCG groups, respectively (NS). Only 82.9% of animals (34/41) were flushed and embryos were recovered in 18 animals (52.9%), with 2.7 ± 0.4 and 2.7 ± 0.7 embryos in the FSH and eCG groups, respectively (NS). Large unovulated follicles (diameter >13 mm) were observed in 34.1% of animals (14/41) on Day 14 and most of them (71.4%) were in the group treated with eCG (10/14; P < 0.05). In conclusion, the use of eCG resulted in a higher number of preovulatory follicles (7-13 mm in diameter) than FSH. However, the percentage of animals with large unovulated follicles was also higher in the eCG-treated group, resulting in no differences in the number of CL counted or embryos obtained per treatment.

Lissencéphalies : aspects cliniques et génétiques

The term lissencephaly covers a group of rare malformations sharing the common feature of anomalies in the appearance of brain convolutions (characterised by simplification or absence of folding) associated with abnormal organisation of the cortical layers as a result of neuronal migration defects during embryogenesis. Children with lissencephaly have feeding and swallowing problems, muscle tone anomalies (early hypotonia and subsequently limb hypertonia), seizures (in particular, infantile spasms) and severe psychomotor retardation. Multiple forms of lissencephaly have been described and their current classification is based on the associated malformations and underlying aetiology. Two large groups can be distinguished: classical lissencephaly (and its variants) and cobblestone lissencephaly. In classical lissencephaly (or type I), the cortex appears thickened, with four more or less disorganised layers rather than six normal layers. In the variants of classical lissencephaly, extra-cortical anomalies are also present (total or subtotal agenesis of the corpus callosum and/or cerebellar hypoplasia). The classical lissencephalies and the variant forms can be further divided into several subgroups. Four forms can be distinguished on the basis of their genetic aetiology: anomalies in the LIS1 gene (isolated lissencephaly and Miller-Dieker syndrome), anomalies in the TUBA3 and DCX genes, and lissencephalies caused by mutations in the ARX gene (XLAG syndrome, X-linked lissencephaly with agenesis of the corpus callosum). The incidence of all forms of type I lissencephaly is around 1 in 100,000 births. In addition to these four entities, isolated lissencephalies without a known genetic defect, lissencephalies with severe microcephaly (microlissencephaly) and lissencephalies associated with polymalformative syndromes are also included in the group of classical lissencephalies. Cobblestone lissencephaly (formally referred to as type II) is present in three entities: the Walker-Warburg, Fukuyama and MEB (Muscle-Eye-Brain) syndromes. It is characterised by global disorganisation of cerebral organogenesis with an uneven cortical surface (with a pebbled or cobblestone appearance). Microscopic examination reveals total disorganisation of the cortex and the absence of any distinguishable layers. Management is symptomatic only (swallowing problems require adapted feeding to prevent food aspiration, articular and respiratory physiotherapy to prevent orthopaedic problems resulting from hyptonia and treatment of gastrooesophageal reflux). The epilepsy is often resistant to treatment. The encephalopathy associated with lissencephaly is often very severe and affected children are completely dependent on the carer.

Molecular heterogeneity in fetal forms of type II lissencephaly

Type II lissencephaly (type II LIS) is a group of autosomal recessive congenital muscular dystrophies (CMD) associated with defects in alpha-DG O-glycosylation, which comprises Walker-Warburg syndrome, Fukuyama cerebral and muscular dystrophy, or muscle-eye-brain disease. The most severe forms of these diseases often have a fetal presentation and lead to a pregnancy termination. We report here the first molecular study on fetal type II LIS in a series of 47 fetuses from 41 unrelated families. Sequencing of the different genes known to be involved in alpha-DG O-glycosylation allowed the molecular diagnosis in 22 families: involvement of POMT1 was demonstrated in 32% of cases, whereas POMGNT1 and POMT2 were incriminated in 15% and in 7% of cases, respectively. We found 30 different mutations in these three genes, 25 were described herein for the first time, 15 in POMT1, and five in POMT2 and POMGNT1. Despite sequencing of FKRP, FCMD, and LARGE, no definitive molecular diagnosis could be made for the other half of our cases. Preliminary results concerning genotype-phenotype correlations show that the choice of the first gene sequenced should depend on the clinical severity of the type II LIS; POMT1 and POMT2 for severest clinical picture and POMGNT1 for milder disease. The other genes, FKRP, FCMD, and LARGE, seem not to be implicated in the fetal form of CMD.

Detection of an Alu insertion in the POMT1 gene from three French Walker Warburg syndrome families

Walker Warburg syndrome (WWS) is the most severe of a group of multiple congenital disorders known as lissencephaly type II ( LIS Type II) associated with congenital muscular dystrophy and eye abnormalities. The POMT1 gene is the most frequently affected found in 20% of patients with WWS. We describe five fetuses with WWS in three non-related families carrying a same mutation in the POMT1 gene. All fetuses presented with tetra ventricular hydrocephaly, and arachnoidal neuroglial ectopia and cortical dysplasia characteristic of LIS type II. We performed sequencing of the POMT1 gene on fetal DNA. The five fetuses were found to share an insertion of an inversed Alu repeated DNA element within exon 3 of the POMT1 gene, all at the heterozygous state except one at the homozygous state. This mutation was associated with a common transition c.2203 C > T (p.Arg735Cys) in exon 20 on the same allele and similar intragenic haplotype, suggesting that the three families could be related or indicating a possible founder effect in France. Insertions of Alu sequences, which are rarely found in coding regions, have occasionally been reported to cause other genetic diseases. However, this is the first report of a retrotransposon insertion in the POMT1 gene associated with WWS.

Treatment of rectosigmoid endometriosis by laparoscopically assisted vaginal rectosigmoidectomy

OBJECTIVE

To describe the use of mechanical anastomoses in cases of laparoscopically assisted vaginal rectosigmoidectomy for the treatment of rectosigmoid endometriosis.

METHODS

Pilot study evaluating eight patients with rectosigmoid endometriosis referred for surgical treatment. All patients were submitted to laparoscopically assisted vaginal segmental resection of the rectosigmoid with anastomoses performed using linear and circular staplers.

RESULTS

The average length of the surgical procedure was 177.5 min and average duration of hospitalization was 4.13 days. There were no intra-operative complications and integrity of the anastomoses was confirmed in all patients. One patient reported partial improvement of symptoms and 7 patients presented complete clinical remission 12 months following surgery.

CONCLUSION

Laparoscopically assisted vaginal segmental resection of the sigmoid infiltrated by endometriosis is a feasible surgical procedure. The technique combines transvaginal access with mechanical intestinal anastomoses performed using linear and circular staplers, and achieves good results with low morbidity.

Phenotypic spectrum of CHARGE syndrome in fetuses with CHD7 truncating mutations correlates with expression during human development

BACKGROUND

The acronym CHARGE refers to a non-random cluster of malformations including coloboma, heart malformation, choanal atresia, retardation of growth and/or development, genital anomalies, and ear anomalies. This set of multiple congenital anomalies is frequent, despite rare patients with normal intelligence, and prognosis remains poor. Recently, CHD7 gene mutations have been identified in CHARGE patients; however, the function of CHD7 during development remains unknown.

METHODS

We studied a series of 10 antenatal cases in whom the diagnosis of CHARGE syndrome was suspected, considering that a careful pathological description would shed light on the CHD7 function during development. CHD7 sequence analysis and in situ hybridisation were employed.

RESULTS

The diagnosis of CHARGE syndrome was confirmed in all 10 fetuses by the identification of a CHD7 heterozygous truncating mutation. Interestingly, arhinencephaly and semi-circular canal agenesis were two constant features which are not included in formal diagnostic criteria so far. In situ hybridisation analysis of the CHD7 gene during early human development emphasised the role of CHD7 in the development of the central nervous system, internal ear, and neural crest of pharyngeal arches, and more generally showed a good correlation between specific CHD7 expression pattern and the developmental anomalies observed in CHARGE syndrome.

CONCLUSIONS

These results allowed us to further refine the phenotypic spectrum of developmental anomalies resulting from CHD7 dysfunction.