69, XXX Karyotype Triploidy Syndrome

Headnote

Keywords: Triploidy, plecentamegali, polydactily

[PP-305]

Triploidy is a chromosomal abnormality characterized by the presence of an additional haploid set of chromosomes. Triploidy is estimated to occur in 3% of conceptions. Most triploids are aborted spontaneously in the first trimester, while those who proceed to live birth die at an early postnatal stage. Second trimester maternal serum alpha-fetoprotein (MS-AFP), human chorionic gonadotrophin (hCG), and unconjugated estriol (uE3) levels are evaluated in pregnancies to determine the risk of aneuploidy. The common clinical features of triploidy syndrome include severe intrauterine growth retardation, macrocephaly, total syndactyly of third and fourth fingers, and CNS, heart, and renal defects, dysplastic cranial bones, eye defects, cleft lip and/or palate, malformed ears, micrognathia, genital anomalies, asymmetric growth retardation, rarely spina bifida, hypotonicity, and atrophy of the cerebral cortex and corpus callosum. Hydatidiform mole, one of the characteristic features of pure triploidy, is found in more than 90% of cases.In our case, a woman at the age of 37 years and 16 weeks 4 day of gestation of her first pregnancy was referred for higher risk of trisomy 21 (1/8) and higher level of thyroid hormones. After evulation, plecantomegaly, oligohydroamnios and polydactily were detected. Amniocentesis was performed at 16 week 5 day of pregnancy. The karytotype was 69, XXX, consistent with a triploid fetus. Upon termination of the pregnancy,gross examination of the 21 week fetus revealed a female fetus weighing 380 g, with only polydactily,iugr and parcial mole. Our case is very isolated form of triploidy. This shows that triploidy can be seen without gross anomaly. First trimester examination is very important for diagnosis. Patients with higher risk for triploidy amniocent