Avtor/Urednik		Benedik-Dolničar, Majda; Slavec, Breda
Naslov		Ocenitev primarne hemostaze z novim analizatorjrm trombocitne funkcije
Prevedeni naslov		The platelet function analyzer (PFA-100): a novel system for evaluation of primary haemostasis
Tip		članek
Vir		Med Razgl
Vol. in št.		Letnik 39, št. Suppl 5
Leto izdaje		2000
Obseg		str. 47-54
Jezik		slo
Abstrakt		The PFA-100TM system provides an in-vitro method for measurement of platelet function in whole blood anticoagulated with sodium citrate. This system simulates primary hemostasis after cut of small vessel. The PFA-100TM is a microprocessor controlled instrument and it uses two disposable cartridges: a collagen/epinephrin (coll/epi) and collagen/ADP (coll/ADP). This causes adhesion and aggregation of platelets. The process culminates in the formation of a primary platelet plug and time which is necessary for this is called the closure time (CT). In this study we established normal reference ranges for a CT in 52 children and adoles- cents without bleeding disorders. The mean value with cartridge coll/epi was 119 and mean value +- 2 SD from 78 to 160 s, the mean value with cartridge coll/ADP was 90 and mean value +-2SD from 55 to 124s. In the group of 21 patients with von Willebrand disease (vWd) 14 patients had prolonged CT with both cartridges, 5 only with cartridge coll/epi, one only with coll/ADP and one patient with mild form of vWd had normal CT with both cartridges. We established sensitivity of 86% for CT coll/epi and 81% for coll/ADP and specificity 98% for coll/epi and 91,8% for coll/ADP. Negative predictive value for coll/epi was 94,5% and for coll/ADP 89,6%; positive predictive value for coll/epi was 94,7% and for coll/ADP 100%. All patients with severe form of congenital disorders of platelet function, all patients with low number of platelets and the patient with uremia had prolonged CT but all patients with severe form of haemophilia A had normal CT. We can conclude that PFA-100TM system is very useful as a routine screening test for assessing primary haemostasis disorders.
Izvleček		PFA-100 (platelet function analyzer - analizator funkcije trombocitov) je sistem, ki in vitro meri delovanje trombocitov (Tr) v krvi, odvzeti z dodatkom Natrijevega citrata, ter posnema primarno hemostazo po poškodbi majhne žile. Kontrolirano spodbujanje Tr s kolagenom se dogaja v eni celici s 10 mikro g adrenalina (Kol/Adr) in v drugi s 50 mikro g ADP (Kol/ADP), kar povzroči prilepljanje in zlepljanje Tr. Čas, ki je potreben za nastanek trombocitnega čepa, imenujemo zapiralni čas (ZČ). V študijo smo vključili 52 otrok in mladostnikov brez motenj krvavitev in določili referenčne vrednosti za ZČ. S testno celico Kol/Adr je bila povprečna vrednost 119, povprečje +- 2 standardni deviaciji (SD) od 78 do 160 s, s testno celico Kol/ADP pa povprečna vrednost 90 in povprečje t 2 SD od 55 do 124 s. V skupini 21 bolnikov s von Willebrandovo boleznijo (vWB) jih je imelo 14 podaljšan ZČ z obema testnima celicama, pri 5 je bil podaljšan le ZČ Kol/Adr, pri enem le Kol/ADP, pri enem z zelo lahko obliko vWB tipa 1 pa je bil ZČ normalen z obema testnima celicama. Ugotovili smo občutljivost za ZČ Kol/Adr 86 % in za Kol/ADP 81 % ter specifičnost za Kol/Adr 98 % in za Kol/ADP 91,8 %. Negativna napovedna vrednost je bila za Kol/Adr 94,5 %, za Kol/ADP pa 89,6 % in pozitivna napovedna vrednost za Kol/Adr 94,7 %, za Kol/ADP 100 %. Bolniki s težko obliko prirojene motnje delovanja trombocitov, z znižanim številom trombocitov in bolnica s pridobljeno motnjo trombocitov zaradi uremije so imeli podaljšan ZČ, vsi bolniki s težko obliko hemofilije A pa normalnega. Lahko zaključimo, da je testni sistem PFA zelo uporaben kot rutinski presejalni test za odkrivanje motenj primarne hemostaze.
Deskriptorji		PLATELET FUNCTION TESTS VON WILLEBRAND'S DISEASE CHILD ADOLESCENCE