title: The presence of heparin-platelet factor 4 antibodies as a marker of hypercoagulability during hemodialysis.
abstract: We have assessed the prevalence of heparin-platelet factor 4 antibodies in a group of 100 patients on chronic intermittent hemodialysis with repeated exposure to heparin in order to establish the clinical significance of an immunological response to heparin. Heparin-induced platelet reactivity was studied in a subgroup of 86 patients. Routine laboratory parameters such as plasma C-reactive protein, albumin and immunoglobulins were included. Clinical endpoints were thrombosis in blood access, change of blood access, other thromboembolic events, bleeding complications, falling platelet count, and ischemic vascular disease or death within 1 year of blood sampling. Blood access thrombosis was a frequent complication (26%), often leading to change of dialysis blood access (21%). Antibodies were detected in 3-6% of hemodialysis patients and antibody levels correlated to blood access thrombosis and change of access (p<0.05). An unexpected finding was that of increased heparin-induced platelet reactivity in 36% of the control group of 24 uremic patients prior to dialysis or exposure to heparin. The findings suggest that antibodies to heparin-platelet factor 4 may contribute to hypercoagulability during hemodialysis, leading to thrombotic complications in affected patients.
authors.affiliation: Department of Clinical Chemistry, Danderyd Hospital, Stockholm, Sweden. anna.yu@ks.se
authors.forename: Anna
authors.initials: A
authors.lastname: Yu
authors.forename: Stefan H
authors.initials: SH
authors.lastname: Jacobson
authors.forename: Anette
authors.initials: A
authors.lastname: Bygdén
authors.forename: Nils
authors.initials: N
authors.lastname: Egberg
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000906:Antibodies / Q000097:blood*; D001792:Blood Platelets / Q000502:physiology; D004797:Enzyme-Linked Immunosorbent Assay; D006493:Heparin / Q000276:immunology* / Q000494:pharmacology; D006801:Humans; D008875:Middle Aged; D010974:Platelet Aggregation; D010978:Platelet Factor 4 / Q000276:immunology* / Q000494:pharmacology*; D006435:Renal Dialysis / Q000009:adverse effects*; D019851:Thrombophilia / Q000150:complications / Q000276:immunology*; D013927:Thrombosis / Q000150:complications / Q000276:immunology
chemical_list: D000906:Antibodies; D010978:Platelet Factor 4; D006493:Heparin