To evaluate the capacities of adaptation of the STA-R analyzer (Diagnostica Stago, Asnieres, France) to the study of pediatric hemostasis, classical studies were undertaken and they have included: (1) Within-run assays (n = 21, 2 control levels) and day-to-day precision studies (n = 20, 2 control levels) for the following tests: prothrombin time (PT), activated partial thromboplastin time (APTT), factor II (FII), factor VII + X (FVII + X), factor V (FV), fibrinogen (fg) and antithrombin (AT); (2) Comparison of the results of APTT, FII, FVII + X, FV and fg assays (in 50 plasmas) obtained with STA-R and STA (analyzer currently used, in our pediatric laboratory). Specific pediatric evaluation has included: (1) Evaluation of the STA-R results for low concentrations of the coagulation factors; (2) Determination of the lowest dead volume; (3) Introduction of peculiar samples among "routine" series. The results showed that within-run assays and day-to-day precision studies have confirmed the good performances of the STA-R. The comparison of the STA-R and STA results from 50 plasmas shows a correlation coefficient of 0.990, 0.995, 0.996, 0.997 and 0.996 for APTT, fg, FII, FVII + V and FV respectively. Such results are confirmed for low concentrations of coagulation factors. The acceptable dead volume could be lowered down to 50 microliters. Very small samples, selected assays and emergencies could be easily introduced among routine series. It is concluded that the STA-R showed very good technical performances. The STA-R is adapted to the routine tests as well as to the very specific samples of neonates and children.
Adolescent ; Blood Coagulation Factors ; Blood Coagulation Tests ; instrumentation ; Child ; Child, Preschool ; Fibrinogen ; Hemostasis ; Humans ; Infant ; Partial Thromboplastin Time

OBJECTIVETo explore the distribution and influence factors of protein C (PC), protein S (PS) and antithrombin (AT) activities and to determine the prevalence of their deficiencies in the Chinese Han healthy population.

METHODSHealthy volunteers including blood donors and individuals for routine check-up were recruited from 4 Chinese medical centers. The plasma levels of PC, PS and AT activities were measured. The plasma levels of activities were measured by chromogenic substrate assay (AT and PC) and clotting assay (PS).

RESULTSA total of 3493 healthy Chinese adults had been recruited in this study. Males had higher PS and PC activities than females, especially for PS (P < 0.01). PC activities increased with age in both sexes but decreased in men after 50 years old. There was no significant change with age were of PS in 50 years old, while there was a decline in males and a rise in females above 50 years old. AT tended to increase with age in women but decreased with age in men after 50 years old. Based on the age and gender, the general prevalence of PC, PS and AT deficiencies in the general Chinese Han population were 1.15%, 1.49% and 2.29%, respectively.

CONCLUSIONPC, PS and AT activities have correlation with age and gender in Chinese Han population. Reference range should be laid down and deficiencies should be identified

Adolescent ; Adult ; Aged ; Aged, 80 and over ; Antithrombin III ; metabolism ; Antithrombin III Deficiency ; epidemiology ; Antithrombins ; metabolism ; Asian Continental Ancestry Group ; Female ; Humans ; Male ; Middle Aged ; Plasma ; metabolism ; Prevalence ; Protein C ; metabolism ; Protein C Deficiency ; epidemiology ; Protein S ; metabolism ; Protein S Deficiency ; epidemiology ; Young Adult