Author/Editor		Benedik-Dolničar, Majda
Title		Von Willebrandova bolezen: prepoznavanje in zdravljenje
Translated title		Von Willebrand disease: diagnosis and treatment
Type		članek
Source		Zdrav Vestn
Vol. and No.		Letnik 73, št. Suppl 1
Publication year		2004
Volume		str. I-147-54
Language		slo
Abstract		Background. Von Willebrand disease (VWD) is a most frequently inborn bleeding disorder caused by quantitative or qualitative defects of von Willebrand factor (VWF). VWF promotes platelet-vessel wall (adhesion) and platelet-platelet interaction (aggregation). It is also the carrier for factor Vlll (F Vlll) in plasma. A deficiency of VWF may results in impairment of both, primary and secondary haemostasis. Therefore, patients with VWD can have bleeding symptoms typical for the defect in primary haemostasis (mucocutaneous haemorrhages). In severe deficiency of VWF there are also haemarthroses and haematomas typical for patients with coagulation defects. Several types and subtypes of VWD have been described. The diagnosis is based on measurements of VWF concentration and activity and F Vlll activity in plasma. The tests identifying VWD subtypes are ristocetin induced platelet agglutination (RIPA), multimeric analysis of VWF and measurement of the binding of VWF to F VIII. Conclusions. Due to heterogeneity of VWFdefects, the correct diagnosis of types and subtypes is sometimes difficult but is important for appropriate treatment. There are two main therapeutic options for patients with VWD: desmopressin and blood derived concentrates of F VIII/VWF. In certain cases antifibrinolytics and hormones can be suitable treatment. Desmopressin is the treatment of choice in patients with type 1 VWD. It raises endogenous F Vlll and VWF and thereby corrects the intrinsic coagulation defect as well as the prolonged bleeding time (BT) or closure time (CT-PFA'°°) in most type 1 VWD patients. In type 3 and in the majority of type 2 patients desmopressin is not effective and it is necessary to use concentrates containing F Vlll and VWF. These are always effective in raising of F VIll activity, whereas the BT/CT may not be completely corrected, but the normalisation of the BT/CT is not always necessary.
Summary		Izhodišča. Von Willebrandova bolezen (VWB) je najpogostejša prirojena motnja strjevanja krvi, ki jo povzroči odsotnost, pomanjkanje ali motnja v delovanju von Willebrandovega faktorja (VWF). VWF omogoča prilepljanje (adhezijo) trombocitov na žilno steno in zlepljanje (agregacijo) trombocitov. Deluje tudi kot prenašalna molekula faktorja Vlll (F VIII) v plazmi. Pomanjkanje VWF povzroči motnjo v primarni in lahko tudi v sekundarni hemostazi. Bolniki s VWB imajo krvavitve, značilne za motnjo primarne hemostaze (sluznične in kožne krvavitve), v primeru težkega pomanjkanja VWF pa se pojavljajo tudi krvavitve v sklepe, mišice in obsežne podkožne krvavitve, ki so značilne za koagulacijske motnje. Opisanih je več tipov in podtipov VWB. Diagnoza temelji na merjenju koncentracije antigena VWF v plazmi, določanju aktivnosti VWF, merjenju koagulacijske aktivnosti F VIII v plazmi. Za opredelitev podtipov VWB pa je potrebno napraviti tudi test aglutinacije trombocitov z ristocetinom (RIPA test), analizirati sestavo multimerov VWF, določiti količino VWF v trombocitih in napraviti test, ki ocenjuje vezavo VWF na F Vlll. Zaključki. Zaradi velike heterogenosti motnje je natančna opredelitev tipa in podtipa včasih težka, vendar pa pomembna zaradi izbire primernega načina zdravljenja. Na voljo sta dva načina zdravljenja: dezmopresin (DDAVP) in plazemski koncentrat FVIII-VWF. Včasih pa zadostujejo že zdravila, ki lahko vplivajo na zaustavljanje krvavitve (antifibrinolitiki, hormoni). Dezmopresin je metoda izbire pri bolnikih s tipom I VWB. Pri večini prehodno poveča raven endogenega F VIII in VWF v plazmi in tako popravi motnjo v intrinzični poti koagulacije ter skrajša čas krvavitve po metodi Ivy (ČK) oz. zapiralnega časa (ŽČPFA'°°). Pri večini bolnikov s tipom 2 VWB in pri bolnikih s tipom 3 VWB DDAVP ni učinkovit, zato je potrebna uporaba koncentrata F VIII, ki ima ohranjeno aktivnost VWF. (Izvleček skrajšan pri 2000 znakih).
Descriptors		VON WILLEBRAND'S DISEASE VON WILLEBRAND FACTOR DESMOPRESSIN FACTOR VIII