title: Factor XI deficiency diagnosed following use of adalimumab.
abstract: Adalimumab is a drug used in the treatment of refractory psoriasis. We present a case of a 55-year-old male patient who developed petechiae and purpura after the ninth dose of adalimumab therapy. The results of laboratory investigations revealed factor XI (F.XI) deficiency. It should be recognized that F XI deficiency may develop in patients using long-term adalimumab, leading to increased risk of bleeding.
authors.affiliation: Department of Hematology, Bezmialem Vakif University, Faculty of Medicine, Fatih, Istanbul, Turkey.
authors.forename: Guven
authors.initials: G
authors.lastname: Cetin
authors.affiliation: Internal Medicine Clinic, Bezmialem Vakif University, Faculty of Medicine, Fatih, Istanbul, Turkey.
authors.forename: Cumali
authors.initials: C
authors.lastname: Karatoprak
authors.affiliation: Internal Medicine Clinic, Bezmialem Vakif University, Faculty of Medicine, Fatih, Istanbul, Turkey.
authors.forename: Muharrem
authors.initials: M
authors.lastname: Kiskac
authors.affiliation: Internal Medicine Clinic, Bezmialem Vakif University, Faculty of Medicine, Fatih, Istanbul, Turkey.
authors.forename: Mehmet
authors.initials: M
authors.lastname: Zorlu
authors.affiliation: Department of Physical Medicine and Rehabilitation, Bezmialem Vakif University, Faculty of Medicine, Fatih, Istanbul, Turkey.
authors.forename: Aylin
authors.initials: A
authors.lastname: Rezvani
authors.affiliation: Internal Medicine Clinic, Bezmialem Vakif University, Faculty of Medicine, Fatih, Istanbul, Turkey.
authors.forename: Mehmet Ali
authors.initials: MA
authors.lastname: Cikrikcioglu
mesh_terms: D000068879:Adalimumab; D000893:Anti-Inflammatory Agents / Q000008:administration & dosage / Q000009:adverse effects* / Q000627:therapeutic use; D061067:Antibodies, Monoclonal, Humanized / Q000008:administration & dosage / Q000009:adverse effects* / Q000627:therapeutic use; D005173:Factor XI Deficiency / Q000139:chemically induced* / Q000473:pathology; D006470:Hemorrhage / Q000139:chemically induced; D006801:Humans; D008297:Male; D008875:Middle Aged; D011565:Psoriasis / Q000188:drug therapy; D011693:Purpura / Q000139:chemically induced
chemical_list: D000893:Anti-Inflammatory Agents; D061067:Antibodies, Monoclonal, Humanized; D000068879:Adalimumab
keywords: Adalimumab; bleeding; bleeding diathesis; factor XI deficiency; psoriasis