P.L. Meroni

‘Criteria’ aPL tests: Report of a Task Force and preconference workshop at the 13th International Congress on Antiphospholipid Antibodies, Galveston, Texas, April 2010:

Current classification criteria for definite antiphospholipid syndrome (APS) mandate the use of one or more of three positive ‘standardized’ laboratory assays to detect antiphospholipid antibodies (aPL) (viz: anticardiolipin [aCL] IgG and IgM; anti-β2glycoprotein I [anti-β2GPI] antibodies IgG and IgM; and/or a lupus anticoagulant [LAC]), when at least one of the two major clinical manifestations (thrombosis or pregnancy losses) are present. Although, efforts of standardization for these ‘criteria’ aPL tests have been conducted over the last 27 years, reports of inconsistencies, inter-assay and inter-laboratory variation in the results of aCL, LAC, and anti-β2GPI, and problems with the interpretation and the clinical value of the tests still exist, which affect the consistency of the diagnosis of APS. A Task Force of scientists and pioneers in the field from different countries, subdivided in three working groups, discussed and analyzed critical questions related to ‘criteria’ aPL tests in an evidence-based manner, during the 13th International Congress on Antiphospholipid Antibodies (APLA 2010, April 13–16, 2010, Galveston, TX). These included: review of the standardization and the need for international consensus protocol for aCL and anti-β2GPI tests; the use of monoclonal and/or polyclonal standards in the calibration curve of those tests; and the need for establishment of international units of measurement for anti-β2GPI tests. The group also reviewed the recently updated guidelines for LAC testing, and analyzed and discussed the possibility of stratification of ‘criteria’ aPL tests as risk factors for APS, as well as the clinical value of single positive vs. multiple aPL positivity. The group members presented, discussed, analyzed data, updated and re-defined those critical questions at a preconference workshop that was open to congress attendees. This report summarizes the findings, conclusions, and recommendations of this Task Force.

Risk factors for a first thrombotic event in antiphospholipid antibody carriers. A multicentre, retrospective follow-up study

Objectives: To asses risk factors for a first thrombotic event in antiphospholipid antibody (aPL) positive carriers and evaluate the efficacy of prophylactic treatments. Methods: Recruitment criteria were age 18–65 years, no history of thrombosis, positivity for lupus anticoagulant and/or IgG/IgM anticardiolipin antibody (aCL) on ⩾2 occasions at least 6 weeks apart. Demographic, laboratory and clinical parameters were collected at enrolment and at the time of the thrombotic event. Results: 370 patients/subjects (mean (SD) age 34 (9.9) years) were analysed retrospectively for a mean (SD) follow-up of 59.3 (45.5) months. Thirty patients (8.1%) developed a first thrombotic event during follow-up. Hypertension and medium/high levels of IgG aCL were identified by multivariate logistic regression analysis as independent risk factors for thrombosis. Thromboprophylaxis during high-risk and long-term periods was significantly protective. Conclusions: Hypertension or medium/high titres of IgG aCL are risk factors for a first thrombotic event in asymptomatic aPL carriers and primary prophylaxis is protective.

EULAR recommendations for women's health and the management of family planning, assisted reproduction, pregnancy and menopause in patients with systemic lupus erythematosus and/or antiphospholipid syndrome.

Objectives Develop recommendations for womens health issues and family planning in systemic lupus erythematosus (SLE) and/or antiphospholipid syndrome (APS). Methods Systematic review of evidence followed by modified Delphi method to compile questions, elicit expert opinions and reach consensus. Results Family planning should be discussed as early as possible after diagnosis. Most women can have successful pregnancies and measures can be taken to reduce the risks of adverse maternal or fetal outcomes. Risk stratification includes disease activity, autoantibody profile, previous vascular and pregnancy morbidity, hypertension and the use of drugs (emphasis on benefits from hydroxychloroquine and antiplatelets/anticoagulants). Hormonal contraception and menopause replacement therapy can be used in patients with stable/inactive disease and low risk of thrombosis. Fertility preservation with gonadotropin-releasing hormone analogues should be considered prior to the use of alkylating agents. Assisted reproduction techniques can be safely used in patients with stable/inactive disease; patients with positive antiphospholipid antibodies/APS should receive anticoagulation and/or low-dose aspirin. Assessment of disease activity, renal function and serological markers is important for diagnosing disease flares and monitoring for obstetrical adverse outcomes. Fetal monitoring includes Doppler ultrasonography and fetal biometry, particularly in the third trimester, to screen for placental insufficiency and small for gestational age fetuses. Screening for gynaecological malignancies is similar to the general population, with increased vigilance for cervical premalignant lesions if exposed to immunosuppressive drugs. Human papillomavirus immunisation can be used in women with stable/inactive disease. Conclusions Recommendations for womens health issues in SLE and/or APS were developed using an evidence-based approach followed by expert consensus.

Pathogenic anti-nucleosome antibodies:

There is increasing evidence that in systemic lupus erythematosus, nucleosomes, the basic chromatin component, represent both a driving immunogen and a major in vivo target for antibodies. Either a disturbed apoptosis or a reduced clearance of apoptotic cells by phagocytes may lead to an increased exposure of apoptotic nucleosomes to the immune system. These nucleosomes, which have been cleaved and modified during the process of apoptosis, escape normal clearance and encompass epitopes that normally are not encountered by the immune system. This may then lead to tolerance breaking and autoimmunity by the activation of nucleosome-specific autoreactive T cells (that help B cells) and subsequently to the production of anti-nucleosome, anti-histone and anti-DNA autoantibodies. Some anti-nucleosome antibody subsets are pathogenic and are involved in the nephritogenic process in systemic lupus erythematosus. Accordingly, several studies reported: (i) increased plasma circulating nucleosomes that positively correlated with an active disease, (ii) nucleosomes in typical glomerular deposits as well as in the basement membrane of non-lesional skin of systemic lupus erythematosus patients and (iii) a close correlation between nephritis and the presence of anti-nucleosome antibodies. Recent studies reported anti-nucleosome antibodies also in primary anti-phospholipid syndrome and particularly in patients with associated lupus-like disease.

Impact of in utero environment on the offspring of lupus patients

The number of patients affected by systemic lupus erythematosus (SLE) that decide to have children has greatly increased probably because of recent improvements in the diagnosis and management of the disease. This has stimulated our interest in defining the outcome of children, focusing both on neonatal problems and long term development. SLE patients still carry a risk of pregnancy loss. However, due to careful monitoring and treatment by a multidisciplinary team, the number of losses has dramatically decreased, but an increased number of preterm deliveries is still a problem. Neonatal lupus is linked to the presence of anti-Ro/SS-A and anti-La/SS-B antibodies in the mother, although other factors probably of fetal origin are important. Neonatal lupus is a complex condition whose most serious manifestation is the congenital heart block (CHB). Usually, children with complete CHB need permanent pacing, but apparently do not have neuropsychological problems. Studies focusing on the neuropsychological development of SLE offspring show an increased number of learning disabilities in children with normal intelligence levels. Fetal consequence of maternal treatment need to be considered choosing non teratogenic drugs, but the withdrawal of medications just because the patient is pregnant should be avoided to avoid SLE flares.

European attempts for the standardisation of the antiphospholipid antibodies

According to the Sydney criteria, antiphospholipid syndrome (APS) diagnosis is closely related to the demonstration of antiphospholipid antibodies (aPL) in patients sera. For this purpose, three different assays are conventionally accepted: lupus anticoagulant (LA), anticardiolipin (aCL) and anti-β2 glycoprotein I (β2GPI) antibodies. LA, described in the 1950s is a coagulation-based functional assay, which indirectly detects the presence of aPL. The aCL ELISA was developed in 1985; the identification of β2GPI as a major target of aPL, allowed the introduction of anti-β2GPI ELISA. Even if the diagnostic criteria for APS have been well defined, the laboratory detection of aPL is not always reproducible for many reasons. To achieve a univocal diagnostic definition of APS, efforts were made to reduce the inter- and/or intra-laboratory variability of the diagnostic tests. In this article, we analyse the studies performed to standardise aPL assays that were developed within the European Forum on Antiphospholipid Antibodies.

Obstetric and vascular APS: Same autoantibodies but different diseases?

Beta2 glycoprotein I (β2GPI)-dependent antiphospholipid antibodies (aPLs) are the main pathogenic autoantibody population and at the same time the laboratory diagnostic tool for the antiphospholipid syndrome (APS). These antibodies are responsible for both the vascular and the obstetric manifestations of the syndrome but the pathogenic mechanisms behind these manifestations are not the same. For example, thrombotic events do not appear to play a major role in APS miscarriages and a direct reactivity of β2GPI-dependent aPLs on decidual and trophoblast cells was reported. A local expression of β2GPI on these tissues was reported both in physiological conditions and in APS women, thus explaining the local tropism of the autoantibodies. The two hit hypothesis was suggested to explain why the vascular manifestations of APS may occur only occasionally in spite of the persistent presence of aPLs. This is not apparently the case for the obstetric variant of the syndrome, making the difference even more striking. A different pathogenesis may also provide the rationale for the well-known fact that the vascular and the obstetric manifestations may occur independently although in a minority of cases.

Mosaic of anti-endothelial antibodies: Review of the first international workshop on anti-endothelial antibodies: clinical and pathological significance Milan, 9 November 1994

PL Meroni, 1 MA Khamashta, 2P Youinou 3 and Y Shoenfeld 4 1Istituto di Medicina Interna, Malattie Infettive and Immunopatologia, University of Milan, Italy, 2Lupus Research Unit, The Rayne Institute, St. Thomas’ Hospital, London, UK, 3Laboratory of Immunology, Brest University Medical School, Brest, France and 4Research Unit of Autoimmune Diseases, Sheba Medical Center and Tel-Aviv University, Israel

Immune function in children born to mothers with autoimmune diseases and exposed in utero to immunosuppressants.

The administration of immunosuppressive drugs during pregnancy is often necessary in women with autoimmune diseases. Teratogenicity of immunosuppressives during pregnancy has been evaluated, only few data exist about the effects on immune systems. We therefore performed a pilot study on the influence of foetal exposure to immunosuppressives on immune function of babies born to mothers with autoimmune disorders. We investigated serological and cellular parameters as indicators of immune system status. We included in the study 14 babies (mean age 11 months, range 1—24) born to mothers with autoimmune diseases and exposed in utero to different immunosuppressants and, as controls, 14 babies whose mothers had autoimmune manifestations but did not receive immunosuppressive therapy. We evaluated: (i) complete blood count, (ii) immunoglobulin levels and IgG subclasses, (iii) antibody response to hepatitis B vaccine, (iv) leukocyte subpopulations and (v) interleukin-2 and interferon γ in vitro production by resting or activated peripheral blood mononuclear cells. We did not find statistically significant differences between exposed and not exposed babies or among treatments for the tested parameters. Immunosuppressive regimens currently in use for controlling maternal autoimmune disorders do not significantly affect the immune status of the offspring. Lupus (2007) 16, 651—656.

Vitamin D and antiphospholipid syndrome

Vitamin D (vitD) has been shown to have multiple immunomodulatory properties. Hypovitaminosis D has been described in many systemic autoimmune diseases. Antiphospholipid syndrome (APS), an autoimmune disease characterized by immune-mediated thrombosis and pregnancy loss, is a peculiar model for studying vitD, since these patients do not usually have a full-blown autoimmune disease, nor do they have particular restrictions regarding sun exposure. We assessed 25-OH vitD levels in 115 APS and 128 normal healthy donors (NHD) with the LIAISON® chemiluminescent immunoassay by DiaSorin (Italy). Median values were lower in APS patients than in NHD, with the greatest difference occurring during summertime (p < 0.01), suggesting that APS patients may be somehow prevented from vitD generation upon sun exposure. In our cohort, APS patients may have been instructed to use sunscreens in the presence of positive antinuclear antibodies (ANA). Comparing patients with positive and negative ANA, we found comparable vitD levels during the summer. By subdividing APS patients according to clinical features, thrombotic APS patients showed significantly lower levels than did pure obstetric APS patients (p < 0.01). In conclusion, our study confirms previous reports of hypovitaminosis D in APS patients, making them more similar to patients with other systemic autoimmune diseases than NHD. Hypovitaminosis D may be part of the mosaic of factors that determine autoimmunity, rather than a consequence of chronic disease and its treatment. The observation that patients with thrombotic APS, an aggressive phenotype, may be more deficient than those with exclusive obstetric manifestations fits well with the beneficial effects of vitD on thrombosis described both in vitro and in vivo. Therefore, there may be a rationale to assess the efficacy of vitD supplementation in APS patients.