2023 ACMG Annual Clinical Genetics Meeting Digital Edition: Poster Gallery-Prenatal Cytogenetic Test Review Adds Value to Clinical Care

Pdf Summary

Summary:<br /><br />This document discusses the importance of pre-test review of genetic orders in prenatal cytogenetic testing. Mistakes in test orders can lead to irrevocable clinical decisions and mismanagement of samples. Genetic counselors play a crucial role in reviewing test orders, confirming that the correct tests are ordered based on indications, and resolving any discrepancies between paperwork and electronic orders. They also monitor ongoing fetal array and molecular tests to prevent delays and address problems quickly.<br /><br />The document provides three case examples to illustrate the value of pre-test review. In the first case, a pregnant patient with a family history of X-linked hydrocephalus had amniotic fluid (AF) received for testing. The genetic counselor determined that the most important test was for the familial variant associated with the previous child's condition. Instead of waiting for cultures, the AF was sent directly for testing, resulting in a positive detection of the familial variant.<br /><br />In the second case, a pregnant patient with fetal skeletal abnormalities had amniotic fluid received for testing. The genetic counselor performed a chromosomal microarray (CMA) and identified a large region of homozygosity on chromosome 14, suggesting a diagnosis of Kagami-Ogata syndrome. Recognizing that confirmatory testing for UPD14 was necessary, the genetic counselor prioritized this test over the skeletal dysplasia sequencing panel, resulting in a timely diagnosis.<br /><br />In the third case, a pregnant patient at high risk for trisomy 13 had a suboptimal chorionic villus sample received for testing. The genetic counselor recommended adding maternal cell contamination (MCC) testing due to the presence of MCC potentially affecting the normal FISH result. MCC testing confirmed maternal contamination, prompting the need for repeat testing by amniocentesis for an accurate fetal chromosome assessment.<br /><br />Overall, these case examples highlight the importance of careful review and communication with healthcare providers in prenatal cytogenetic testing to ensure appropriate test prioritization, avoid unnecessary procedures, and provide timely and accurate results.

Asset Subtitle

Presenting Author - Danielle LaGrave, MS; Co-Author - Rachel M. Lasher, MS, CGC; Co-Author - Michelle Q. Bosworth, MS; Co-Author - Amanda S. Openshaw, MS, CGC; Co-Author - Katie Rudd, PhD, FACMG; Co-Author - Erica F. Andersen, PhD, FACMG;

Meta Tag

Chromosomal Abnormalities

Clinical Cytogenetics

Counseling

Cytogenetics

Prenatal Diagnosis

Co-Author Rachel M. Lasher, MS, CGC

Co-Author Michelle Q. Bosworth, MS

Co-Author Amanda S. Openshaw, MS, CGC

Co-Author Katie Rudd, PhD, FACMG

Co-Author Erica F. Andersen, PhD, FACMG

Presenting Author Danielle LaGrave, MS

Keywords

pre-test review

genetic orders

prenatal cytogenetic testing

test orders

clinical decisions

mismanagement of samples

genetic counselors

fetal array

molecular tests

case examples