Abstract
We studied 99 patients with systemic autoimmune disease (5 males, 94 women; mean age 37 year, range 16-72): 28 Primary Antiphospholipid Syndrome, 67 Systemic lupus Erythematosus, 1 Mixed Connective Tissue Disease, 2 Undifferentiated Connective Tissue Disease and 1 Discoid Lupus. Based on the observation that native PT shows conformational changes in presence of Ca++ ions and discloses new epitopes available for binding with phospholipids, we performed 3 different methods for the detection of aPT in presence and absence of Ca++, finding a different incidence of specific autoantibodies, associated with clinical features of APS (aPT in presence of Ca++) or non associated (aPT in absence of Ca++). The presence of aPT was significantly associated also with the presence of Lupus Anticoagulant (LAC). The detection of aPT (in presence of Ca++) significantly enhances diagnostic sensibility of APS allowing the identification of a subset of patients (6/99) with clinical features of APS, but with negative LAC, aCL and a beta2-GPI; in fact (limited to thrombotic episodes) the sensibility rises from 56.2% with one test (LAC) to 81.1% with the application of LAC, aCL, a(beta)2GPI and aPT.
Publication types
-
Comparative Study
-
Evaluation Study
MeSH terms
-
Adolescent
-
Adult
-
Aged
-
Antibody Specificity
-
Antiphospholipid Syndrome / blood
-
Antiphospholipid Syndrome / complications
-
Antiphospholipid Syndrome / diagnosis
-
Antiphospholipid Syndrome / immunology*
-
Autoantibodies / blood
-
Autoantibodies / immunology*
-
Calcium / pharmacology
-
Chelating Agents / pharmacology
-
Connective Tissue Diseases / complications
-
Connective Tissue Diseases / immunology
-
Edetic Acid / pharmacology
-
Enzyme-Linked Immunosorbent Assay
-
Female
-
Glycoproteins / immunology
-
Humans
-
Immunoglobulin G / immunology
-
Lupus Coagulation Inhibitor / analysis
-
Lupus Erythematosus, Discoid / complications
-
Lupus Erythematosus, Discoid / immunology
-
Lupus Erythematosus, Systemic / complications
-
Lupus Erythematosus, Systemic / immunology
-
Male
-
Middle Aged
-
Mixed Connective Tissue Disease / complications
-
Mixed Connective Tissue Disease / immunology
-
Predictive Value of Tests
-
Prothrombin / immunology*
-
Prothrombin Time
-
Thrombophilia / etiology
-
Thrombophilia / immunology*
-
beta 2-Glycoprotein I
Substances
-
Autoantibodies
-
Chelating Agents
-
Glycoproteins
-
Immunoglobulin G
-
Lupus Coagulation Inhibitor
-
beta 2-Glycoprotein I
-
Prothrombin
-
Edetic Acid
-
Calcium