APC resistance in neonates and infants: Adjustment of the aPTT - based method

Prothrombin G20210A Gene Mutation and Further Prothrombotic Risk Factors in Childhood Thrombophilia

“…12,15,16 Thrombosis during childhood is frequently discussed as being due to nongenetic endogenous or exogenous trigger mechanisms. [17][18][19][20] Because in our study Ϸ62% of patients with thrombosis had an underlying disease, we can support these findings. Moreover, the frequencies of hereditary risk factors in patients with spontaneous thrombosis were not significantly different from the frequencies found in patients with underlying disease, but there was a trend toward higher carrier frequencies in spontaneous thrombosis.…”

“…In the current study, the carrier frequencies of these prothrombotic defects were each in the same range as for adult patients and confirm earlier reports of smaller studies on childhood thrombophilia. 1,2,[12][13][14][17][18][19][20][21][23][24][25][26] The only exception from this general finding was the carrier frequency of protein C deficiency, which was found to be relatively high in the patients investigated here, especially in patients with spontaneous thrombosis. On the one hand, this may be attributed to the small number of patients; on the other hand, according to the trend toward higher carrier frequencies of all risk factors in the spontaneous thrombosis group, this finding may reflect the high importance of protein C deficiency for young patients.…”

“…On the other hand, several cases have been published showing the relevance of risk factors within the hemostatic system for thromboembolic episodes during childhood and adolescence. [17][18][19][20][21] In this report we present the results of a multicenter case-control study on pediatric patients with venous thrombosis with regard to the prothrombin G20210A mutation and further hereditary risk factors.…”

Arginine 506 to glutamin mutation in the factor V gene in infancy and childhood: evidence of fibrinolytic impairment

“…Platelet poor plasma was snap-frozen and stored in plastic tubes at )79°C. The response to activated protein C and the Arg 506 to Gln mutation in the factor V gene was measured as described earlier [18,19]. Tissue-type plasminogen activator (t-PA) antigen urokinase-type plasminogen activator, (u-PA) antigen, plasminogen activator inhibitor (PAI) 1 antigen D-Dimer and thrombin generation (F1+2) were analysed serially in duplicate within 1 month of collection.…”

Thromboembolic Diseases in Neonates and Children

“…Suitable proteinbased assays, i.e. APC-resistance [66,67], protein C activity, free and total protein S antigen, antithrombin activity, fibrinogen concentration, plasminogen activity, coagulation factors VIIIC and XII, lipoprotein (a) [68,69], and fasting homocysteine concentrations should be investigated along with DNA-based assays, i.e. factor V G1691A mutation, prothrombin G20210A variant and MTHFR C677T genotype.…”