Fanny Pelluard

Mutations in KIAA0586 Cause Lethal Ciliopathies Ranging from a Hydrolethalus Phenotype to Short-Rib Polydactyly Syndrome

KIAA0586, the human ortholog of chicken TALPID3, is a centrosomal protein that is essential for primary ciliogenesis. Its disruption in animal models causes defects attributed to abnormal hedgehog signaling; these defects include polydactyly and abnormal dorsoventral patterning of the neural tube. Here, we report homozygous mutations of KIAA0586 in four families affected by lethal ciliopathies ranging from a hydrolethalus phenotype to short-rib polydactyly. We show defective ciliogenesis, as well as abnormal response to SHH-signaling activation in cells derived from affected individuals, consistent with a role of KIAA0586 in primary cilia biogenesis. Whereas centriolar maturation seemed unaffected in mutant cells, we observed an abnormal extended pattern of CEP290, a centriolar satellite protein previously associated with ciliopathies. Our data show the crucial role of KIAA0586 in human primary ciliogenesis and subsequent abnormal hedgehog signaling through abnormal GLI3 processing. Our results thus establish that KIAA0586 mutations cause lethal ciliopathies.

Contribution of referent pathologists to the quality of trophoblastic diseases diagnosis

OBJECTIVE To evaluate the contribution of referent pathologists (RPs) to the quality of diagnosis of trophoblastic diseases and to study the level of diagnostic agreement between the initial pathologists and the RPs. METHODS This observational retrospective study was carried between 1 November 1999 and 11 January 2011 using the database of the French Trophoblastic Disease Reference Centre in Lyon. All files for hydatiform moles (HMs), trophoblastic tumours and non-molar pregnancies for which there was an initial suspicion of trophoblastic disease were included, whenever there was rereading of the slides by an RP. A total of 1851 HMs and 150 gestational trophoblastic tumours were analysed. RESULTS When the initial pathologist diagnosed a complete mole, the RP confirmed the diagnosis in 96% of cases. When the initial pathologist diagnosed a partial mole, the RP confirmed the diagnosis in only 64% of cases. For trophoblastic tumours, when the initial pathologist diagnosed a choriocarcinoma, the RP confirmed the diagnosis in 86% of cases. When the initial anatomopathology suggested an invasive mole, the diagnosis was confirmed in 96% of cases. Finally, when the initial diagnosis was a placental site trophoblastic tumour or an epithelioid trophoblastic tumour, the RP confirmed the diagnosis in 60 and 100% of cases, respectively. CONCLUSION A systematic policy of rereading of slides for all suspicious moles improves the quality of management of trophoblastic diseases at a national level.

Fetal phenotype associated with the 22q11 deletion

The 22q11 deletion syndrome is one of the most common human microdeletion syndromes, with a wide spectrum of abnormalities. The fetal phenotype associated with the 22q11 deletion is poorly described in the literature. A national retrospective study was performed from 74 feto‐pathological examinations. The objectives were to evaluate the circumstances of the 22q11 deletion diagnosis and to describe fetal anomalies. Post mortem examinations were performed after 66 terminations of pregnancy and eight fetal deaths. The series included nine fetuses from the first trimester, 55 from the second trimester, and ten from the third trimester. A 22q11 FISH analysis was recommended for 57 fetuses after multidisciplinary prenatal diagnostic counseling and for 17 fetuses by a fetal pathologist. Conotruncal heart defects were the most common anomalies (65 fetuses), followed by thymus defects (62 fetuses), and malformations of the urinary tract (25 fetuses). This study identified several unusual and severe features rarely described in the literature. Neurological abnormalities were described in ten fetuses, with seven neural tube defects and five arhinencephalies. This series also included lethal malformations: two hypoplastic left heart syndromes, two bilateral renal agenesis, and one tracheal agenesis. Genetic analysis for a 22q11 deletion is usually indicated when a congenital conotruncal heart and/or thymus defect is detected, but might also be useful in case of other lethal or severe malformations that initially led to the termination of pregnancy.

Reduced placental telomere length during pregnancies complicated by intrauterine growth restriction.

Objectives Recent studies have shown that telomere length was significantly reduced in placentas collected at delivery from pregnancies complicated by intrauterine growth restriction secondary to placental insufficiency. Placental telomere length measurement during ongoing pregnancies complicated by intrauterine growth restriction has never been reported. This was the main objective of our study. Methods In our center, late chorionic villus samplings were performed between 18 and 37 weeks of amenorrhea in 24 subjects with severe intrauterine growth restriction (cases) and in 28 subjects with other indications for prenatal diagnosis (controls). Placental insufficiency was assessed by histo-pathological examination. Relative measurement of telomere length was carried out prospectively by quantitative Fluorescent In Situ Hybridization using fluorescent Peptide Nucleic Acid probes on interphase nuclei obtained from long-term cultured villi and with an automated epifluorescent microscope. A quantitative Polymerase Chain Reaction technique was performed to confirm the quantitative Fluorescent In Situ Hybridization results. The number of copies of gene loci encoding the RNA template (hTERC) and the catalytic subunit (hTERT) of the enzyme complex telomerase were also estimated in these placentas by Fluorescent In Situ Hybridization. Results Mean fluorescence intensity of telomere probes estimated by quantitative Fluorescent In Situ Hybridization was significantly less for cases compared to controls (p<0.001). This result indicated that mean telomere length was significantly reduced in placentas during pregnancies complicated by intrauterine growth restriction. Reduced telomere length was confirmed by the quantitative Polymerase Chain Reaction technique. No copy number variation of the hTERC and hTERT loci was noticed for cases, or for controls. Conclusion This study clearly demonstrates a reduction of placental telomere length in ongoing pregnancies (from 18 to 37 weeks of amenorrhea) complicated by severe intrauterine growth restriction secondary to placental insufficiency.

Severe X-linked chondrodysplasia punctata in nine new female fetuses

Conradi–Hünermann–Happle [X‐linked dominant chondrodysplasia punctata 2 (CDPX2)] syndrome is a rare X‐linked dominant skeletal dysplasia usually lethal in men while affected women show wide clinical heterogeneity. Different EBP mutations have been reported. Severe female cases have rarely been reported, with only six antenatal presentations.

Fetal presentation of PHACES syndrome

PHACES syndrome, proposed by Frieden et al. [1996], consists of Posterior fossa CNS anomalies, Hemangioma, Arterial anomalies, Coarctation of the aorta and Cardiac anomalies, Eye anomalies, and Sternal defects. The condition has been reviewed extensively elsewhere [Gorlin et al., 2001]. Earlier, Leiber [1982] noted the syndrome in binary, tertiary, or quaternary combinations. Here, we present two cases of possible PHACES syndrome with fetal presentation. Case 1 involved the third pregnancy of a 29-year-old woman. The second pregnancy ended in the induced abortion of an anencephalic fetus. In the third pregnancy, an arachnoid cyst was suspected at 22 weeks gestation on ultrasound. A second ultrasound at 28 weeks gestation was consistent with Dandy– Walker malformation and abortion was induced at 30 weeks. Postmortem findings included Dandy–Walker malformation and aortic stenosis. Case 2 involved the third pregnancy of a 27-year-old woman. The second pregnancy ended in spontaneous abortion. A third trimester routine ultrasound suggested Dandy–Walker malformation and absent eyeballs. Abortion was induced at 36 weeks gestation. Postmortem examination showed macrosomia, prominent forehead, large anterior fontanelle, cryptophthalmia, excess cervical skin, absent optic nerves and optic chiasm, and Dandy–Walker malformation. To our knowledge, these are the first two cases described prenatally that suggest PHACES syndrome. Both of our cases had fetal presentation. Neither of our cases had hemangioma. However, almost all of them developed postnatally [Rossi et al., 2001]. Although various eye anomalies have been reported, particularly anterior segment abnormalities and microphthalmia, anophthalmia present in case 2, has not been previously described.

Incidence of obstetrical thrombotic thrombocytopenic purpura in a retrospective study within thrombocytopenic pregnant women. A difficult diagnosis and a treatable disease

BackgroundThrombotic thrombocytopenic Purpura (TTP) defined as ADAMTS-13 (A Disintegrin And Metalloprotease with ThromboSpondin type 1 domain 13) activity <10 % is a rare aetiology of thrombocytopenia during pregnancy, although the precise incidence is unknown. During pregnancy, the diagnosis of TTP is crucial as it has high feto-maternal morbidity-mortality and requires urgent plasma exchange. The purpose of this study was to assess the incidence of TTP retrospectively and to describe case presentations and follow-up.MethodsA monocentric retrospective study (2008–2009) was conducted among pregnant women followed in a tertiary care obstetrical unit who experienced at least one episode of severe thrombocytopenia (platelets ≤75 G/L) during 2008 and 2009. In cases of uncertain aetiology of thrombocytopenia, ADAMTS-13 activity was assessed by the full length technique.ResultsAmong 8,908 deliveries over the 2 year period, 79 women had a platelet count nadir ≤75 G/L. Eighteen had a known aetiology of thrombocytopenia and 11 were lost to follow-up. Among 50 remaining patients, ADAMTS-13 activity was undetectable (<5 %) in 4, consistent with the diagnosis of TTP. Platelet count spontaneously normalized in 3 patients after delivery. None presented focal cerebral involvement. Three of the four, who were primipara patients, had a sustained severe deficiency in the absence of anti-ADAMTS-13 antibodies, and ADAMTS-13 gene sequencing indicated a constitutive deficiency. The fourth, a multipara patient, had an acquired, auto-immune TTP. Placental pathology in the three primipara patients showed severe and non-specific ischemic lesions. Two patients lost their babies shortly after birth. In subsequent pregnancies in these two patients, prophylactic plasma infusion initiated early with increasing volume throughout pregnancy prevented TTP relapse, improved placental pathology, and led to normal delivery.ConclusionsThe prevalence of TTP among thrombocytopenic pregnant women is high, up to 5 % in a tertiary unit. Platelet count normalization after delivery does not eliminate TTP. Clinicians should be aware of TTP during pregnancy, and, even if assessed retrospectively, ADAMTS-13 assessment is of particular importance for identifying patients with congenital TTP. In these patients, preventive plasma infusion and/or exchange can dramatically improve foetal prognosis, resulting in successful childbirth.

Pathological Findings in Feto-maternal Hemorrhage.

Feto-maternal hemorrhage (FMH) is the cause of late fetal death in 1.6%–11% of cases. In spite of this high frequency, its pathological features have received little attention. The definitive diagnosis of lethal FMH requires confirmation of sufficient fetal blood volume loss. This is determined by tests such as the Kleihauer-Betke test, which may not have been obtained or not have been available before the autopsy. The pathologist may offer a tentative diagnosis of FMH from the autopsy findings. The objective of this study was to better characterize the placental and fetal autopsy findings in lethal FMH. This was a retrospective study of 17 cases of FMH proven by a positive Kleihauer-Betke test. The cases were selected from the autopsy files of the Department of Pathology, Centre Hospitalier Universitaire de Bordeaux. The pathological reports as well as the placental and fetal photographs and the microscopic slides of each case were systematically reviewed. The fetal autopsy findings in FMH are characterized by a eutrophic pale macerated fetus, low liver weight, absent intrathoracic petechiae, increased extramedullary hematopoiesis in the liver and kidney, and increased circulating nucleated red blood cells. The placenta shows an increased frequency of intervillous thrombi. Although nonpathognomonic, some of the pathological features are strongly suggestive of FMH. When the latter is present, a Kleihauer-Betke test should be performed, even some days after the delivery.

Fraser syndrome: Features suggestive of prenatal diagnosis in a review of 38 cases.

Fraser syndrome (FS) is a rare malformation recessive disorder. Major criteria are cryptophtalmos, syndactyly, respiratory, genital and urinary tract anomalies. Few prenatal presentations have been reported.

Truncus arteriosus communis: report of three cases and review of literature

Background Truncus arteriosus communis (TAC) is a congenital heart defect in which the physiologic arterial common trunk was not divided into aorta and pulmonary artery trunk. Objectives In this paper, we report on three observed cases from which we looked for (in conjunction with literature review) the different causes of TAC many of which have genetic origins. Methods We collected three clinical files of fetuses having a TAC. Two of them were examinated after a medical termination of pregnancy motivated by severe cardiopathy. The malformation had been diagnosed based on different techniques: echocardiography, skeletal radiography, arteriography, fetal autopsy, karyotype and fluorescence in situ hybridization (FISH). Results Imaging and fetopathological examination revealed the presence of TAC type 3 and 4 in the Van Praaghs classification. FISH analysis showed a 22q11.2 deletion in one fetus in favour of Digeorge syndrome. The karyotype analysis performed in two cases was normal. Conclusion Truncus arteriosus is a rare pathology caused by numerous etiologies from which many of them have genetic origin. This malformation can be diagnosed early during prenatal period. Postmortem fetopathological examination allows a better diagnosis approach and eventually a genetic counseling in recurrent cases such as case of consanguinity.