Repeated failed non-invasive prenatal testing owing to low cell-free fetal DNA fraction and increased variance in a woman with severe autoimmune disease

摘要

A 41-year-old woman (gravida 2 para 1) with autoimmune disease was referred for genetic counseling following an increased risk of trisomy 21 (1:164) on combined first-trimester screening. She had a history of severe autoimmune thrombocytopenia, with past treatments including splenectomy, steroids, intravenous immunoglobulin (IVIG) and cyclosporin. She also had an autoimmune neutropenia, a past history of myasthe-nia gravis treated with thymectomy and Hashimoto's thyroiditis. Her weight was 67 kg.