Recurrent Cystic Hygroma and Poor Pregnancy Outcomes in a Single Patient.

Abstract

Background: Cystic hygroma is a rare, benign cystic congenital malformation of the lymphatic vessels that occurs in 1 in 800 pregnancies and 1 in 8000 live births. The etiology of CH still remains unknown, and there are very few cases of successive pregnancies all containing CH. Literature suggests that CH is passed down in an autosomal recessive inheritance pattern, which is what is suspected in a case such as this. Cases: These cases are unique recurrence of cystic hygroma in three successive pregnancies in a single patient over a period of 4 years and 6 months. Patient had history of ischemic stroke and diagnosed with protein C deficiency at 19 years old and she was on Coumadin and low dose aspirin (ASA) prior to and less than 6 weeks of gestation during the first and second pregnancies but on Lovenox prior to her third pregnancy and continued throughout the pregnancy. Chromosomal analysis of the first fetus showed a 7:11 translocation between the short arm of chromosome 11 and the short arm of chromosome 7 with breakpoints of chromosome t (7;11)(p(13;p15.1). Conclusion: To this day there has been no reported literature of CH complicated by this specific type of translocation; leading us to the conclusion that it was likely coincidental. Moreover, both the parents, the second and the third fetuses all had normal chromosomal analysis and normal microarray. Unfortunately, whole genome and exon sequencing could not be performed but the patient had negative maternal expanded carrier screening. Teaching Points Pregnancies complicated by cystic hygroma require more than just mere analysis for chromosome anomaly but also require fetal DNA analysis and evaluations to rule out other fetal conditions such as immune and non-immune causes of fetal hydrops, and fetal structural abnormalities like congenital heart disease, thoracic mases that can obstruct vascular and lymphatic drainage, skeletal dysplasia and sometimes inborn error of metabolism. The CH in each pregnancy was suspected to be related familial predisposition or autosomal recessive inheritance pattern that caused damage to the lymphatic system during fetal development because there were no other known identifiable genetic or environmental causes in the three cases.