Kevin Spencer1. 1. Clinical Biochemistry Department, Harold Wood Hospital, Gubbins Lane, Romford RM3 0BE, UK. KevinSpencer1@aol.com
Abstract
BACKGROUND: In a rapid point-of-care screening programme for chromosomal anomalies, analysis of biochemical markers in maternal blood can now be accomplished in a rapid time frame (less than 20 min). The need to leave whole blood samples some 10 min for coagulation and a further 5 min for centrifugation adds additional processing time. METHODS: The possibilities for reducing this processing time were investigated using various anticoagulated blood collection systems and the Kryptor analytical platform. Plasma levels of alpha-fetoprotein (AFP), pregnancy-associated plasma protein-A (PAPP-A) and free human chronic gonadotrophin beta-subunit (beta-hCG) were compared with those in maternal serum. RESULTS: From the mean results from ten patients it was shown that use of heparin plasma resulted in a statistically significant reduction in levels of PAPP-A and that EDTA plasma reduced the levels of PAPP-A dramatically. For AFP, levels in citrated plasma and EDTA plasma were also significantly reduced, whereas levels of free beta-hCG were not affected. CONCLUSION: Use of alternative sample types for PAPP-A is not possible. The sample of choice for first trimester screening using the Kryptor platform is maternal serum.
BACKGROUND: In a rapid point-of-care screening programme for chromosomal anomalies, analysis of biochemical markers in maternal blood can now be accomplished in a rapid time frame (less than 20 min). The need to leave whole blood samples some 10 min for coagulation and a further 5 min for centrifugation adds additional processing time. METHODS: The possibilities for reducing this processing time were investigated using various anticoagulated blood collection systems and the Kryptor analytical platform. Plasma levels of alpha-fetoprotein (AFP), pregnancy-associated plasma protein-A (PAPP-A) and free human chronic gonadotrophin beta-subunit (beta-hCG) were compared with those in maternal serum. RESULTS: From the mean results from ten patients it was shown that use of heparin plasma resulted in a statistically significant reduction in levels of PAPP-A and that EDTA plasma reduced the levels of PAPP-A dramatically. For AFP, levels in citrated plasma and EDTA plasma were also significantly reduced, whereas levels of free beta-hCG were not affected. CONCLUSION: Use of alternative sample types for PAPP-A is not possible. The sample of choice for first trimester screening using the Kryptor platform is maternal serum.
Authors: S Kate Alldred; Yemisi Takwoingi; Boliang Guo; Mary Pennant; Jonathan J Deeks; James P Neilson; Zarko Alfirevic Journal: Cochrane Database Syst Rev Date: 2017-03-15
Authors: S Kate Alldred; Yemisi Takwoingi; Boliang Guo; Mary Pennant; Jonathan J Deeks; James P Neilson; Zarko Alfirevic Journal: Cochrane Database Syst Rev Date: 2017-03-15
Authors: Claire H Kim; Shelley S Tworoger; Meir J Stampfer; Simon T Dillon; Xuesong Gu; Sherilyn J Sawyer; Andrew T Chan; Towia A Libermann; A Heather Eliassen Journal: Sci Rep Date: 2018-05-30 Impact factor: 4.379
Authors: S Kate Alldred; Yemisi Takwoingi; Boliang Guo; Mary Pennant; Jonathan J Deeks; James P Neilson; Zarko Alfirevic Journal: Cochrane Database Syst Rev Date: 2015-11-30
Authors: S Kate Alldred; Boliang Guo; Yemisi Takwoingi; Mary Pennant; Susanna Wisniewski; Jonathan J Deeks; James P Neilson; Zarko Alfirevic Journal: Cochrane Database Syst Rev Date: 2015-12-10