title: Activated protein C resistance: the influence of ABO-blood group, gender and age.
abstract: We have evaluated the potential influence of ABO-blood group, gender and age, on laboratory procedures used for detection of Activated Protein C Resistance (APCR), using over 300 normal donor samples and two distinct laboratory test procedures, one based on an Activated Partial Thromboplastin Time (APTT) and the other on a Russell Viper Venom Time (RVVT). We observed a statistically significant influence of ABO-blood group on APTT test times, both in the presence and absence of Activated Protein C (APC), which was no longer evident when using assay ratios. This ABO effect was not observed using the RVVT-based assay procedure. We also observed a gender effect on the APTT-based procedure, such that females (compared to males) provided shorter APTT test times (both with and without APC). This effect was still evident when using APTT assay ratios, but was again not observed using the RVVT-based procedure. We also observed an age related increase in APTT ratios. Interestingly, some previous studies have reported some specific gender and age related effects on APTT-based testing, but reports using RVVT-based testing are lacking, as are ABO related studies. Such findings should be considered as potential variables when associating specific laboratory based findings of APCR to clinical thrombophilia conditions.
authors: Department of Haematology, Institute of Clinical Pathology and Medical Research (ICPMR), WSAHS, Westmead Hospital, NSW 2145, Australia. emmanuel@icpmr.wsahs.nsw.gov.au
authors: Emmanuel J
authors: EJ
authors: Favaloro
authors: Soma
authors: S
authors: Soltani
authors: Jane
authors: J
authors: McDonald
authors: Ella
authors: E
authors: Grezchnik
authors: Leanne
authors: L
authors: Easton
mesh_terms: D000017:ABO Blood-Group System / Q000097:blood*; D020016:Activated Protein C Resistance / Q000097:blood*; D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D001315:Australia; D001780:Blood Coagulation Tests; D019411:Clinical Laboratory Techniques; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012015:Reference Standards; D012737:Sex Factors; D019851:Thrombophilia / Q000503:physiopathology
chemical_list: D000017:ABO Blood-Group System