S Hashimoto, L Igarashi, M Kobayashi, H Tsutsumi

Abstract

Almost all triploid fetuses abort spontaneously in the first trimester; live-born triploid infants are rare. We herein report a triploid infant who survived for >250 days. The infant was delivered at 33 weeks 4 days of gestation because of severe fetal growth restriction. The birth weight was 1,108 g, and multiple malformations were present. Chromosomal analysis demonstrated a karyotype of 69,XXY. At the time of this report, she lived at home and was 280 days old. A review of triploid infants revealed that the relatively unique clinical features of triploidy were syndactyly of the third and fourth fingers and abnormal erythrocyte indices. The associated karyotypes were 69,XXX and 69,XXY but not 69,XYY. Two of five infants died of pneumonia. Two infants, including the infant described herein, developed infantile spasms after the age of 200 days. Triploid infants with long-term survival are at high risk of developing pneumonia and infantile spasms.

幾乎所有三倍體胎兒在孕早期均會出現自發性流產，活產的三倍體嬰兒十分罕見；我們在此報道一例存活時間長於250天的三倍體嬰兒。此患兒因嚴重的宮內發育遲緩於孕33+4周出生，出生體重1180g，出生時即發現其有多種先天畸形。染色體核型分析結果為69XXY。目前，此患兒在家中已存活超過280天。通過對三倍體嬰兒的回歸，發現三倍體患兒相對特殊的臨床特點包括：第3、4指並指以及異常的血紅細胞指標。相關的核型包括：69 XXX,69 XXY，而非69 XYY。5例三倍體嬰兒中有兩例死於肺炎。其中兩例，包括我們目前報道的此例，在出生200天後出現嬰兒痙攣症。長期存活的三倍體嬰兒出現肺炎及嬰兒痙攣症的風險高。