Mono-organic versus Multi-organic Involvement in Primary Antiphospholipid Syndrome
Abstract: The prevalence of mono-organic and multi-organic involvement during long-term follow-up in patients with primary antiphospholipid syndrome (pAPS) was investigated. We studied 60 pAPS patients followed up at least 5 years. Patients with associated systemic lupus erythematosus were excluded. All patients received oral anticoagulant therapy. A diagnosis of mono-organic involvement was considered when one organ was affected exclusively, and multi-organic involvement was considered when two or more organs became affected during follow-up. Average age at diagnosis was 32.9  12.4 years, 40 subjects were female and 20 male, and mean disease evolution totaled 11.5  4.5 years. The mean number of clinical events was 3.75  1.87. Among patients, immunoglobulin G anticardiolipin (IgM aCL) titers totaled 50  40.3 IgG phospholipid units, and IgM aCL titers totaled 47.3  35.4 IgM phospholipid units. The most frequent clinical manifestations at study onset were deep venous thrombosis, stroke, pulmonary thromboembolism, fetal loss, and pre-eclampsia. At the beginning of follow-up, 46 patients had mono-organic involvement and 14 had multi-organic involvement (P= 0.0001). In contrast, at the end of the study, only 8 patients still had mono-organic involvement, leading to deep venous thrombosis (n= 3), stroke (n= 3), and retinal thrombosis (n= 2) (P= 0.0001). Kaplan-Meier analysis showed that the probability of remaining with mono-organic involvement decreased throughout the cumulative years, especially during the first 3. The hazard risk ratio for developing multi-organic involvement was 1.47 patients per year. In conclusion, PAPS is a chronic disorder with unpredictable clinical course and multi-organic involvement, especially during the first years. The conversion to multi-organic involvement supports the concept that pAPS is a systemic autoimmune disease.
multi-organic involvement primary antiphospholipid syndrome mono-organic involvement deep venous thrombosis