Normal thrombin generation in neonates in spite of prolonged conventional coagulation tests.
Conventional coagulation tests might be inadequate to explore mechanisms regulating thrombin generation in neonates, because they do not allow full activation of the reduced levels of protein C. Therefore, they do not reflect the action of pro- and anti-coagulants as does the endogenous thrombin potential assessed in the presence of thrombomodulin. Endogenous thrombin potential measured without thrombomodulin was greater than the lower-limit of the adult reference interval in 30% of 109 full-term and 49% of 55 pre-term neonates, a finding consistent with the reduced levels of procoagulants in this setting. When the test was modified adding thrombomodulin, endogenous thrombin potential reverted into the adult reference interval in 97% and 100% full-term and pre-term neonates. In conclusion, the coagulation balance in neonates is restored by the concomitant reduction of pro- and anticoagulants. The restored balance can be shown in vitro by the endogenous thrombin potential test that includes thrombomodulin, but not by conventional coagulation tests.
Tripodi
Armando
A
Angelo Bianchi Bonomi Hemophilia and Thrombosis Center, Department of Internal Medicine, University and IRCCS Maggiore Hospital, Mangiagalli and Regina Elena Foundation, Milano, Italy.
Ramenghi
Luca A
LA
Chantarangkul
Veena
V
De Carli
Agnese
A
Clerici
Marigrazia
M
Groppo
Michela
M
Mosca
Fabio
F
Mannucci
Pier Mannuccio
PM
D000328:Adult; D001777:Blood Coagulation / Q000502:physiology*; D001780:Blood Coagulation Tests; D005260:Female; D005312:Fetal Blood / Q000502:physiology*; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn / Q000097:blood*; D007234:Infant, Premature / Q000097:blood; D008297:Male; D010314:Partial Thromboplastin Time; D012016:Reference Values; D013917:Thrombin / Q000096:biosynthesis*
D013917:Thrombin