Clinical relevance of the recent update of the classification criteria for definite antiphospholipid syndrome: an obstetric medicine clinic series of 107 patients

The clinical and laboratory manifestations profile of antiphospholipid syndrome among Saudi Arabia population: Examining the applicability of Sapporo criteria

Antiphospholipid syndrome is a organized autoimmune disease presented with vascular thrombosis and pregnancy morbidity. The Sapporo classification criteria of APS were revised in 2006 and are used as the main diagnosis guideline, which validity as standard measurements is still in debate. This study observe the clinical and laboratory indices of APS among Saudi patients. This is a retrospective study hospital-based population. The clinical and Laboratory manifestations of diagnosed APS patients from electronical medical records identifies by ICD-9 code 795.79 in the King Saud University Medical City, Riyadh, Saudi Arabia, between 1990 and 2012. We selected patients with ICD-9 code 795.79 as. Sapporo criteria applied to all patients, then divided into cases fulfilled criteria and cases failed the criteria. To notice the difference in clinical and laboratory indices and comorbidities between the two groups, the T-test was performed and Logistic regression for the fulfilled criteria and clinical indices of vascular thrombosis, DVT/PE, recurrent, and pregnancy morbidity. A total of 72 (90%) females and 8 (10%) males, with the female-to-male ratio 9:1. The mean (±SD) age at diagnosis was 28.1 (±8.7) years (range 11-63 years). There were 22 patients (27.5%) attained the revised criteria (APS confirmed) and no significant difference between the two groups was observed (p > 0.2). However, we found Sapporo confirmed APS cases had significantly higher percentage of serological manifestation presence than clinically diagnosed APS cases. Though there is no statistically significance, Sapporo confirmed APS cases had advanced odds of undergoing vascular thrombosis (OR = 1.61, 95%CI) and DVT/PE (OR = 1.53, 95%CI) and lesser odds of undergoing recurrent DVT/PE (OR = 0.67, 95%CI) and pregnancy morbidity (OR = 0.63, 95%CI) than the clinically diagnosed APS cases. Over 70% of the study population with diagnosed APS did not accomplish the revised Sapporo criteria due to negative laboratory manifestations, which reflects heterogeneous but not degreed disease severity profiles.

Diminished expression of β2-GPI is associated with a reduced ability to mitigate complement activation in anti-GPIIb/IIIa-mediated immune thrombocytopenia

Anti-GPIIb/IIIa-mediated complement activation has been reported to be important in the pathogenesis of immune thrombocytopenia (ITP). However, the role of the complement system and the involved regulatory mechanism remain equivocal. Beta2-glycoprotein I (β2-GPI), known as the main target for antiphospholipid autoantibodies, has been demonstrated as a complement regulator. Here, we investigated the complement-regulatory role of β2-GPI in anti-GPIIb/IIIa-mediated ITP. Plasma complement activation and enhanced complement activation capacity (CAC) were found in ITP patients with anti-GPIIb/IIIa antibodies in vivo and in vitro. Diminished plasma levels of β2-GPI were shown in patients of this group, which was inversely correlated with C5b-9 deposition. C5b-9 generation was inhibited by approximate physiological concentrations of β2-GPI, in a dose-dependent manner. Inhibition of C3a generation by β2-GPI and the existence of β2-GPI/C3 complexes in plasma indicated a regulation on the level of the C3 convertase. Furthermore, β2-GPI down-regulated the phosphorylation levels of c-Jun N-terminal kinase (JNK) and cleavage of BH3 interacting domain death agonist (Bid) and ultimately harbored platelet lysis. Our findings may provide a novel link between diminished plasma levels of β2-GPI and enhanced complement activation, indicating β2-GPI as a potential diagnostic biomarker and therapeutic target in the treatment of anti-GPIIb/IIIa-mediated ITP.

Immune thrombocytopenia with antiphospholipid antibodies in monozygotic twins

We describe monozygotic twins with immune thrombocytopenia (ITP) associated to antiphospholipid antibodies with a dissimilar clinical expression. The first patient was diagnosed to have ITP at 63 years old and was treated with corticosteroids. She presented ulterior exacerbations of thrombocytopenia requiring intravenous immunoglobulin and subsequent treatment with rituximab. She ultimately had a favorable response without thrombotic events during follow-up. The second patient who had a history of three spontaneous abortions and endometrial adenocarcinoma in complete remission was evaluated for severe thrombocytopenia, ITP was diagnosed at the age of 63. She was treated with steroids and had a favorable response. After few months she developed deep venous thrombosis and pulmonary embolism requiring anticoagulation therapy without hemorrhagic events. Both patients were found to have antiphospholipid antibodies and HLA DR4 (DRB1*04) and HLA DR5 (DRB1*12). The association of those two entities in monozygotic twins could support the presence of common predisposing genes. However, with both patients being genotipically identical, the clinical expression was different. Those cases highlight the possibility that environmental factors may affect the expression of those disorders.

Challenges in the Diagnosis of the Antiphospholipid Syndrome

Background: The antiphospholipid syndrome (APS) is an important cause of acquired thromboembolic complications and pregnancy morbidity. Its diagnosis is based on clinical and laboratory criteria, defined by strict guidelines. The original clinical and laboratory criteria for the identification of APS patients were published in 1999, in the so-called Sapporo criteria. In 2006 these criteria were revised, and recently more precise guidelines for analysis of the lupus anticoagulant have been provided. However, several questions related to the diagnosis of APS remain unanswered.

Content: In addition to providing a historical perspective, this review covers several challenges in the diagnosis of APS with respect to clinical and laboratory features, while highlighting pathogenic pathways of the syndrome. We discuss ongoing dilemmas in the diagnosis of this complex disease. Although antiphospholipid antibodies are found in association with various clinical manifestations, the older established clinical criteria were not substantively altered in the 2006 update. Several laboratory tests recommended in the latest criteria, including phospholipid-dependent coagulation tests for the detection of the lupus anticoagulant and ELISAs for measuring anticardiolipin and β2-glycoprotein I antibodies, still show methodological and diagnostic shortcomings. In addition, antiphospholipid antibodies have been described against other antigens, but their clinical role remains uncertain.

Conclusions: Despite updated APS criteria, diagnosis of this syndrome remains challenging. Further research on clinically relevant antibodies and standardization of their detection are needed to improve clinical risk assessment in APS.

Revised classification criteria for antiphospholipid syndrome and the thrombotic risk in patients with autoimmune diseases

BACKGROUND

The classification criteria for antiphospholipid syndrome (APS) were updated in 2006.

OBJECTIVE

The aim of the study was to analyze associations between clinical complications and laboratory test abnormalities typical for APS in a group of patients with autoimmune diseases, based on the recently updated criteria.

PATIENTS/METHODS

Three hundred and thirty-six patients were enrolled into the study, with the majority (n = 235) suffering from systemic lupus erythematosus. Laboratory determinations included: lupus anticoagulant (LA), anticardiolipin (aCL) and anti-beta(2)-glycoprotein I (anti-beta(2)GPI) antibodies (ABs) [of both immunoglobulin G (IgG) and IgM class].

RESULTS

A significant association was found between laboratory and clinical features of APS; odds ratios (ORs) for thrombosis associated with the presence of LA, aCL, and anti-beta(2)GPI Abs were 4.04 [95% CI: 2.44-6.68], 3.71 (95% CI 2.32-5.92) and 2.57 (95% CI 1.60-4.1), respectively. Detailed analysis showed marked differences between the risk of clinical complications associated with the presence of an antibody in the IgG class (OR 4.15, 95% CI 2.42-7.12, and OR 4.77, 95% CI 2.37-9.61 for aCL and anti-beta(2)GPI, respectively) and in the IgM class (OR 2.2, 95% CI 1.31-3.70, and OR 1.9, 95% CI 1.15-3.14 for aCL and anti-beta(2)GPI, respectively). The postulated inclusion of anti-beta(2)GPI antibody positivity into the previous laboratory criteria changed only slightly the number of patients diagnosed with APS (from 112 to 117).

CONCLUSIONS

The updated APS classification criteria clearly represent a step forward. However, our results argue against the use of overall positivity for aCL or anti-beta(2)GPI, and favor a clear distinction between the IgG and IgM classes of antiphospholipid ABs. Patients with both LA and anti-beta(2)GPI IgG or LA and aCL IgG positivity may represent the subgroups at the highest risk of thrombotic complications.

Assessment of the 2006 revised antiphospholipid syndrome classification criteria

OBJECTIVE

To analyse antiphospholipid (aPL) antibody-positive patients using the 2006 revised antiphospholipid syndrome (APS) classification criteria.

METHODS

A descriptive study of 200 aPL-positive patients identified in a local, hospital-based registry, analysing demographic, clinical and aPL characteristics. Patients were analysed for (1) fulfillment of the 1999 original (Sapporo) and 2006 revised APS classification criteria; (2) non-criteria aPL features (for all aPL-positive patients, based on the 2006 revised criteria definitions); and (3) non-aPL thrombosis risk factors at the time of the clinical events (for patients with APS, based on the 2006 revised criteria stratifications).

RESULTS

Of the 200 patients, 183 patients had sufficient data for analysis. Of these, 39 (21%) patients did not meet the laboratory requirement of the original 1999 criteria. Of 81 patients with APS who met the 1999 classification criteria, 47 (58%) also met the 2006 revised criteria. Of 63 asymptomatic (no vascular or pregnancy events) aPL-positive patients who met the laboratory requirement of the 1999 classification criteria, 38 (60%) also met the laboratory requirement of the 2006 revised criteria. More than 50% of the patients with APS with vascular events had identifiable non-aPL thrombosis risk factors at the time of clinical events.

CONCLUSIONS

Only 59% of the patients meeting the 1999 APS Sapporo classification criteria met the 2006 APS classification criteria. The revised criteria will have positive implications in APS research by way of limiting the inclusion of a heterogeneous group of patients and also by way of providing a risk-stratified approach.