title: Anti-factor VIII inhibitors and lupus anticoagulants in haemophilia A patients.
abstract: In a study of 170 haemophilia A patients, 43 were found to have an inhibitory effect; seven had anti-factor VIII inhibitors (a-fVIII)(A), 18 had lupus anticoagulants (LAs) with a strong (B: 12) or weak (C: 6) time-dependent effect and 18 had no time-dependent LAs (D). The a-fVIII showed a neutralizing effect only against factor VIII and negative diluted Russell viper venom time (dRVVT). The LAs were diagnosed by dRVVT; the Staclot LA agreed with the dRVVT. During the study, three patients changed from an a-fVIII to an LA pattern; they also modified their clinical response. Our prevalence of a-fVIII was low (4%) and we found 21% of LA, with a high (50%) prevalence of time-dependent inhibition. This pattern raises the possibility of the coexistence of LA and a-fVIII, stressing the need to develop specific tests to identify a-fVIII and LA.
authors.affiliation: Instituto de Investigaciones Hematológicas Mariano R. Castex, Academia Nacional de Medicina, Buenos Aires, Argentina.
authors.forename: A N
authors.initials: AN
authors.lastname: Blanco
authors.forename: M A
authors.initials: MA
authors.lastname: Cardozo
authors.forename: M
authors.initials: M
authors.lastname: Candela
authors.forename: M T
authors.initials: MT
authors.lastname: Santarelli
authors.forename: R
authors.initials: R
authors.lastname: Pérez Bianco
authors.forename: M A
authors.initials: MA
authors.lastname: Lazzari
mesh_terms: D000465:Algorithms; D005169:Factor VIII / Q000037:antagonists & inhibitors*; D006467:Hemophilia A / Q000097:blood* / Q000821:virology; D006801:Humans; D016682:Lupus Coagulation Inhibitor / Q000097:blood*; D011517:Prothrombin Time
chemical_list: D016682:Lupus Coagulation Inhibitor; D005169:Factor VIII