Mosaic trisomy 22 at amniocentesis: Prenatal diagnosis and literature review.

OBJECTIVE: We present prenatal diagnosis of mosaic trisomy 22 at amniocentesis in a pregnancy with facial cleft, oligohydramnios and intrauterine growth restriction (IUGR), and we review the literature. CASE REPORT: A 37-year-old woman underwent amniocentesis at 19 weeks of gestation because of advanced maternal age. Amniocentesis revealed a karyotype of 47,XX,+22[9]/46,XX[9]. Array comparative genomic hybridization (aCGH) analysis on uncultured amniocytes showed a result of arr(22) × 3 [0.8]. Prenatal ultrasound revealed fetal median facial cleft, oligohydramnios and IUGR. Repeat amniocentesis at 22 weeks of gestation using uncultured amniocytes revealed an aCGH result of arr 22q11.1q13.33 (17,397,498-51,178,264) × 2.8 compatible with 80% mosaicism for trisomy 22, and a fluorescence in situ hybridization (FISH) result of mosaic trisomy 22 with trisomy 22 in 54/100 interphase cells. The cultured amniocytes at repeat amniocentesis had a karyotype of 47,XX,+22[12]/46,XX[8]. The parental karyotypes were normal. Polymorphic DNA marker analysis confirmed a maternal origin of the extra chromosome 22. The pregnancy was terminated, and a 256-g female fetus was delivered with facial dysmorphism and median facial cleft. Cytogenetic analysis of the skin fibroblasts revealed a karyotype of 47,XX,+22[33]/46,XX[7]. CONCLUSION: Fetuses with high level mosaicism for trisomy 22 at amniocentesis may present IUGR, facial cleft and oligohydramnios on prenatal ultrasound.

Developmental maxillofacial anomalies.

There is a wide variety of developmental maxillofacial anomalies secondary to defective transformation of the first pair of pharyngeal arches into adult structures. Computed tomography and magnetic resonance imaging are essential to precisely define aberrant maxillofacial anatomy and guide appropriate management. This review article provides an overview of maxillofacial embryogenesis, clinical symptoms, and characteristic imaging features of several anomalies, including choanal atresia, congenital nasal piriform aperture stenosis, dacryocystoceles, nasolacrimal duct stenosis, cleft lip and palate, micrognathia, and midline nasal masses. Finally the major features of common first pharyngeal arch syndromes are discussed.

Disruption of PCP signaling causes limb morphogenesis and skeletal defects and may underlie Robinow syndrome and brachydactyly type B.

Brachydactyly type B (BDB1) and Robinow syndrome (RRS) are two skeletal disorders caused by mutations in ROR2, a co-receptor of Wnt5a. Wnt5a/Ror2 can activate multiple branches of non-canonical Wnt signaling, but it is unclear which branch(es) mediates Wnt5a/Ror2 function in limb skeletal development. Here, we provide evidence implicating the planar cell polarity (PCP) pathway as the downstream component of Wnt5a in the limb. We show that a mutation in the mouse PCP gene Vangl2 causes digit defects resembling the clinical phenotypes in BDB1, including loss of phalanges. Halving the dosage of Wnt5a in Vangl2 mutants enhances the severity and penetrance of the digit defects and causes long bone defects reminiscent of RRS, suggesting that Wnt5a and Vangl2 function in the same pathway and disruption of PCP signaling may underlie both BDB1 and RRS. Consistent with a role for PCP signaling in tissue morphogenesis, mutation of Vangl2 alters the shape and dimensions of early limb buds: the width and thickness are increased, whereas the length is decreased. The digit pre-chondrogenic condensates also become wider, thicker and shorter. Interestingly, altered limb bud dimensions in Vangl2 mutants also affect limb growth by perturbing the signaling network that regulates the balance between Fgf and Bmp signaling. Halving the dosage of Bmp4 partially suppresses the loss of phalanges in Vangl2 mutants, supporting the hypothesis that an aberrant increase in Bmp signaling is the cause of the brachydactyly defect. These findings provide novel insight into the signaling mechanisms of Wnt5a/Ror2 and the pathogenesis in BDB1 and RRS.

Congenital chest malformations: a multimodality approach with emphasis on fetal MR imaging.

Congenital chest malformations can range from small and asymptomatic entities to large space-occupying masses that require immediate surgical treatment. They may affect the foregut, pulmonary airway, and vasculature. Hybrid conditions are commonly seen, with interrelated chest malformations having various radiologic and pathologic features. An understanding of the in utero complications associated with fetal chest masses is essential for appropriate monitoring during pregnancy, treatment recommendations, and delivery management. Technologic advances have greatly improved the diagnosis of fetal anomalies. Congenital chest malformations are usually evaluated in the prenatal period with fetal sonography, but fetal magnetic resonance (MR) imaging is a well-established modality that is used as an adjunct technique in difficult diagnostic situations. MR imaging can provide excellent tissue contrast with more accurate analysis of the fetal anatomy and superior differentiation between the abnormalitites and adjacent structures, thereby allowing early planning of prenatal management.

Modulation of diabetes-induced palate defects by maternal immune stimulation.

Maternal diabetes can induce a number of developmental abnormalities in both laboratory animals and humans, including deformities of the face and palate. The incidence of birth defects in newborns of women with diabetes is approximately 3 to 5 times higher than among nondiabetics. In mice, nonspecific activation of the maternal immune system can reduce fetal abnormalities caused by various etiologies including hyperglycemia. This study was conducted to determine whether nonspecific maternal immune stimulation could reduce diabetes-induced palate defects and orofacial clefts. Female ICR mice were immune stimulated before induction of hyperglycemia with Freund's complete adjuvant (FCA), granulocyte-macrophage colony-stimulating factor (GM-CSF), or interferon-gamma (IFNgamma). Streptozocin was used to induce hyperglycemia (26-35 mmol blood glucose) in females before breeding. Fetuses from 12 to 18 litters per treatment group were collected on Day 17 of gestation. Palate width and length were measured, and the incidence of orofacial clefts was determined. Palate length and width were both decreased by maternal hyperglycemia. Maternal immune stimulation with GM-CSF or FCA limited the degree of palate shortening from the hyperglycemia. Each of the three immune stimulants attenuated significant narrowing of the palate. Rates of orofacial clefts were not significantly different between treatment groups. Palatogenesis is a complex process driven by cellular signals, which regulate cell growth and apoptosis. Dysregulation of cellular signals by maternal hyperglycemia can result in fetal malformations. Maternal immune stimulation may prevent dysregulation of these signaling pathways thus reducing fetal malformations and normalizing palate growth.

The prenatal pituitary gland--hidden and forgotten.

The sella turcica and pituitary gland in a human fetus (18 weeks gestation) with unilateral oro-ocular cleft combined with unilateral cleft lip and palate are described histologically. In this fetus the sella turcica was not a normal sella but a caudally open funnel. The adenopituitary gland tissue was positioned ectopically within the funnel canal and in the pharyngeal submucosa.

The role of folic acid in oral clefting.

The objective of this study is to describe the role of periconceptional folic acid supplementation and assess it's potential in the prevention of foetal abnormalities, and consists of a review of the literature undertaken using an electronic and hand search. This includes research trials and methodology associated with folic acid supplementation. It is recommended that all women planning to conceive should supplement their diet with folic acid in order to prevent abnormalities in neural tube development, particularly if there is a history of a previously affected pregnancy. There is increasing evidence that folic acid supplementation may, in addition, reduce the incidence of oral facial clefting. Further research with multi-disciplinary approaches in biochemistry, genetics, gene/environment interactions, and embryology are indicated.

Síndrome de Eagle / Eagle syndrome

As autoras apresentam um caso de Síndrome de Eagle: o alongamento do processo estilóide e/ou a ossificação do ligamento estiloioídeo, caracterizando clínica e radiograficamente esta anomalia de crescimento

Fissuras lábio-palatais: consideraçöes embriológicas / Cleft lip and palate: embryological considerations

A primeira parte deste ensaio aborda de forma suscinta o mecanismo de formaçäo embriogênica da face, acompanhado de painéis fotográficos que ilustram as malformaçöes faciais mais comuns no homem e os prováveis processos faciais embrionários envolvidos