title: Acquired factor XII deficiency in a woman with recurrent pregnancy loss: working on a differential diagnosis in a single case.
abstract: BACKGROUND
  Antiphospholipid syndrome (APS) has been often associated to RPL since 1980 and some reports in the Literature rarely described antibodies to factor XII in patients with APS.
  
  
  METHODS
  We report the case history of 34-year-old caucasian women with recurrent fetal loss and persistent prolonged activated partial thromboplastin time. Haemostatic tests revealed persistent light decrease of clotting factor XII with normal values of IgG and IgM anticardiolipin antibodies and transient positivity for lupus anticoagulant (LA). Few reports in the Literature described antibodies to factor XII in patient with antiphospholipid syndrome (APS) and transient LA. So, once other causes of RPL were excluded, the patient was diagnosed an unusual form of APS associated to antibodies to factor XII, reduced factor XII plasma levels, transient LA and prolonged activated partial thromboplastin time.
  
  
  CONCLUSIONS
  We suggest to consider also antibodies directed to clotting factors (e.g. factor XII in our case) as second step of thrombophilia screening in RPL, in particular if a persistent prolonged aPTT is present without an apparent cause.
authors.affiliation: Dipartimento Universitario di Scienze Ostetriche Ginecologiche e Medicina della Riproduzione, Area Funzionale di Medicina della Riproduzione ed Endoscopia Ginecologica, Università degli Studi di Napoli Federico II, Naples, Italy. maryduva@yahoo.it
authors.forename: Maristella
authors.initials: M
authors.lastname: D'Uva
authors.forename: Ida
authors.initials: I
authors.lastname: Strina
authors.forename: Antonio
authors.initials: A
authors.lastname: Mollo
authors.forename: Antonio
authors.initials: A
authors.lastname: Ranieri
authors.forename: G
authors.initials: G
authors.lastname: De Placido
authors.forename: P
authors.initials: P
authors.lastname: Di Micco