Dysmorphic villi mimicking partial mole in a case with del(18)(q21).
ABSTRACT In this article, we report the histopathologic findings in a placenta from an early second trimester abortion. The placental villi showed prominent scalloping with many intravillous trophoblastic pseudoinclusions and mild trophoblastic hyperplasia, mimicking the morphology of partial hydatidiform mole. The placental karyotype was 46,XY,del(18)(q21). These histopathologic changes have been previously described in numerical chromosomal aberrations like triploidy, tetraploidy, and trisomies, but not in structural chromosomal abnormalities.
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Article: The placenta may predict the baby.[Show abstract] [Hide abstract]
ABSTRACT: At the basis of the structure of biological systems are genes that regulate the development of the cells that make up the tissues and organs. We humans start off as a symmetrical ball of cells. Even as our first 50 cells begin to separate themselves into an inner cell mass (which will become the embryo, fetus and, eventually, baby) and the trophoblasts (which will become the placenta), genes are regulating the creation of the developmental axes that will form the basis of the entire organism. Defects in the genes that regulate these processes lead to a wide range of embryonic, fetal and neonatal defects, from minor cosmetic abnormalities, to disasters that terminate pregnancy within a few days to weeks after fertilization. Here we describe a particular placental abnormality, propose a mechanical basis for the formation of this defect, and suggest that its presence may be a general marker of developmental abnormalities. By 21 days after fertilization the trophoblasts have begun to sort themselves out into what will become the tree-like structures that make up the placenta: the chorionic trees, branches and villi. The terminal villi (from the Latin for shaggy hair) are finger-like structures that contain the fetal circulation, and like our fingers, are covered with an epithelial layer (in the case of the villi, two layers). The trophoblast bilayer has an inner cytotrophoblast layer made of single nucleatedJournal of Theoretical Biology 12/2003; 225(1):143-5. · 2.30 Impact Factor
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ABSTRACT: Deletions of chromosome 18q are among the most common segmental aneusomies compatible with life. The estimated frequency is approximately 1/40,000 live births [Cody JD, Pierce JF, Brkanac Z, Plaetke R, Ghidoni PD, Kaye CI, Leach RJ. 1997. Am. J. Med. Genet. 69:280-286]. Most deletions are terminal encompassing as much as 36 Mb, but interstitial deletions have also been reported. We have evaluated 42 subjects with deletions of 18q at our institution. This is the largest number of individuals with this chromosome abnormality studied by one group of investigators. Here we report the physical findings in these individuals. We have compared our findings with those of previously reported cases and have found a significantly different incidence of several minor anomalies in our subjects. We also describe here several anomalies not previously reported in individuals with deletions of 18q, including short frenulum, short palpebral fissures, disproportionate short stature, overlap of second and third toes, and a prominent abdominal venous pattern. Characteristics found in subjects were analyzed for correlation with cytogenetic breakpoints. Several traits were found to correlate with the extent of the deletion. Large deletions were associated with significantly decreased head circumference and ear length as well as the presence of proximally placed and/or anomalous thumbs. Individuals with the smallest deletions were more likely to have metatarsus adductus. Although relatively few genotype/phenotype correlations were apparent, these data demonstrate that correlations with breakpoint are possible. This implies that more correlations will become evident when the more precise molecularly based genotyping is completed. These correlations will identify critical regions on the chromosome in which genes responsible for specific abnormal phenotypes are located.American Journal of Medical Genetics 09/1999; 85(5):455-62. · 3.23 Impact Factor
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ABSTRACT: The management of patients with first-trimester spontaneous abortions is handicapped by two problems: difficulty in recognizing conceptions that abort because of abnormal karyotypes and an incomplete understanding of what causes abortions with normal karyotypes. Our goals in this study were to define features useful in distinguishing normal from abnormal karyotype and to identify pathological processes contributing to abortions with a normal karyotype. The study population consisted of 668 well-characterized first-trimester spontaneous abortions derived from a larger study of 1,054 consecutively karyotyped spontaneous abortions. Clinical factors increased in specimens with normal karyotype were maternal age younger than 20 years (P=.0003) and autoimmune markers (P=.0474). Developmental features associated with abnormal karyotype were developmental stage less than 6 weeks (P=.0017), hydropic villi greater than 1 mm (P=.0004), and villi with two or more dysmorphic features (P=.0001). Developmental stage greater than 11.5 weeks was increased with normal karyotype (P=.0001). Histological features increased in specimens with a normal karyotype were chronic intervillositis (P=.0003), increased perivillous fibrin deposition with intermediate trophoblast (P=.0006), decidual plasma cells (P=.0040), deciduitis without plasma cells (P=.0660), and chronic villitis (P=.1581). Overall, 19% of samples with a normal karyotype versus 8% with abnormal karyotype had one or more of these findings (P < .0001). Autoimmune markers, chronic intervillositis, and increased perivillous fibrin with intermediate trophoblast all had positive predictive values greater than 85% for normal karyotype, whereas dysmorphic villi had a positive predictive value of 90% for abnormal karyotype. Patients with recurrent spontaneous abortion and normal karyotype were more likely to have one or more of the histological features listed above (31%) than patients with normal karyotype and no prior abortions (13%) and patients with recurrent abortion and abnormal karyotype (11%).Human Pathlogy 02/1999; 30(1):93-100. · 2.81 Impact Factor