title: The Contact Activation System (CAS) in cord blood: Measurement of CAS components and comparison with mother's blood. A pilot study.
abstract: BACKGROUND
  Classical reference data concerning the coagulation system and fibrinolysis in fetuses and newborns date back to the 1990 s. Since that time a number of methodological or other improvements have been implemented, which may cast some doubt on timeliness of the data. The study objective was to measure the levels of Contact Activation System (CAS) components by antigen, i.e. factors XII and XI (FXII, FXI), prekallikrein (PK) and high molecular weight kininogen (HMWK) in cord blood and maternal blood.
  
  
  METHODS
  The study group consisted of 35 healthy parturient women with an uneventful pregnancy and birth. The samples of cord blood and maternal blood were obtained immediately after delivery, before clumping the umbilical cord. The CAS components were measured by immunoenzymatic method (ELISA).
  
  
  RESULTS
  The median concentrations of CAS components in cord blood plasma and mother's plasma were as follow: FXII: 1.02 (0.60- 2.58) ng/mg protein vs. 0.94 (0.66-1.86) ng/mg protein (p>0.05); FXI: 2.71(0.03-8.0) ng/mg protein vs. 0.92 (0.03-10.44) ng/mg protein (p>0.05); PK: 168.78 (104.28-261.16) pg/mg protein vs. 113.44 (79.94-146.70) pg/mg protein (p>0.05); HMWK: 2169.45 (1530.64- 2539.83) ng/mg protein vs. 2857.96 (2541.52-3161.04) ng/mg protein (p<0.001).
  
  
  CONCLUSIONS
  1. The antigen levels of the three contact factors, i.e. FXII, FXI and PK in the cord blood of full-term and healthy fetuses were similar to those observed in mother's blood immediately after delivery. Only high molecular weight kininogen was found to be lower (accounting for 84% of the values noted in mothers). 2. Based on our measurements, we claim that the cited reference data concerning the contact factors in full-term and healthy newborns are underestimated; hence, new reference values need to be determined for each antigen and activity contact factor level.
authors.affiliation: Department of Propedeutics of Medicine, Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University in Toruń, Poland. Electronic address: kizproped@cm.umk.pl.
authors.forename: Mieczysław
authors.initials: M
authors.lastname: Uszyński
authors.affiliation: State Vacational Collage in Suwałki, Poland.
authors.forename: Jarosław
authors.initials: J
authors.lastname: Kuczyński
authors.affiliation: Department of Pathophysiology, Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University in Toruń, Poland.
authors.forename: Ewa
authors.initials: E
authors.lastname: Żekanowska
authors.affiliation: Regional Hospital in Włocławek, Poland.
authors.forename: Waldemar
authors.initials: W
authors.lastname: Uszyński
mesh_terms: D000328:Adult; D005260:Female; D005312:Fetal Blood / Q000166:cytology / Q000378:metabolism*; D006801:Humans; D010865:Pilot Projects; D011247:Pregnancy / Q000097:blood*; D055815:Young Adult
keywords: Contact Activation System factors; Cord blood