Analysis of Recent Four Years' Cross-Matching Tests of One Commercial Laboratory

The cross-matching test, an essential pre-transfusion test, is usually performed using only a segment of a blood bag and a recipient's blood sample at a commercial laboratory. We analyzed cross-matching test results obtained at LabGenomics laboratory, client of which were mainly small- and medium-sized medical clinics. Data for a total of 12,902 cross-matching tests referred from January 2012 to December 2015 were analyzed for incompatibility in the results and trends based on the distribution of medical clinics. Medical clinics were categorized as nursing home, obstetrics and gynecology, plastic surgery, dental clinic, orthopedic surgery, and others. Incompatible results were observed for 35 cases (1.09%) in 2012, 22 cases (0.68%) in 2013, 31 cases (1.02%) in 2014, and 41 cases (1.20%) in 2015. Overall, 55.4% of referrals came from a nursing home, 6.4% from obstetrics and gynecology, 4.4% from plastic surgery, 20.0% from dental clinic, 5.9 % from orthopedic surgery, and 7.9% from others. Further studies are required to evaluate the efficacy of cross-matching test results and its relationship with transfusion requirements.

An Experience of Using the Harmony Test for Genomics-Based Non-Invasive Prenatal Testing / 임상검사와정도관리

Serological prenatal screening tests are widely used to detect fetal chromosomal abnormalities such as Down and Edward syndromes. Amniocentesis is conducted as a confirmatory test in the screening-positive case. After discovering of presence of fetal cell-free DNA in maternal blood, non-invasive prenatal test (NIPT) coupled with next generation sequencing are performed in abroad. Results of genomics-based NIPT results supplied to Labgenomics laborotory from June, 2013 to August, 2014 were analyzed. Maternal blood samples were collected into specific Cell-Free DNA BCT tube and were transported. The samples were then delivered to Ariosa Diagnostics by FEDEX. Fetal cell-free DNA samples were analyzed using the Harmony test with sequencing of relevant chromosomes and by using the FORTE (fetal-fraction optimized risk of trisomy evaluation) algorism at Ariosa Diagnostics. In all, 149 cases from 28 medical clinics were analyzed. Six subjects were required recollection of samples because of a low fetal DNA fraction in the initially obtained samples. Of these 6 subjects, no sample could be collected from one. Of the remaining 148 cases, 144 had a low risk of trisomy, and 4 had a high risk for Down syndrome, thus providing a positivity percentage of 2.7%. Fetal DNA fraction in the maternal blood samples ranged from 4.2% to 23.7% with a mean value of 12.0%. We have experienced cases with a high risk for Down syndrome with genomics-based NIPT referred to abroad.