Analytical and clinical comparison of different immunoassay systems for the detection of antiphospholipid antibodies.

INTRODUCTION: We evaluated analytical and clinical performances of IgG and IgM anticardiolipin (aCL) antibodies and anti-ß2-glycoprotein I (a-ß2GpI) antibodies and upper limit reference ranges (99th percentiles) in comparison with manufacturer's cutoff values with different commercial methods. METHODS: We assayed aCL and a-ß2GpI in serum samples from 30 healthy individuals, 77 patients with antiphospholipid syndrome (APS) diagnosed according to the Sydney criteria, 51 patients with autoimmune diseases, eight patients with previous thrombotic events, six patients with other diseases, and 18 patients with infectious diseases, using ELISA Inova Diagnostics; EliA Phadia Laboratory Systems; CliA Zenit-RA; and CliA Bio-Flash. RESULTS: Anticardiolipin and a-ß2GpI IgG and IgM immunoassays showed good analytic performances with both 99th percentile and manufacturer's cutoff reference values. Our results showed fair to moderate agreement among assays. In-house cutoff values gave significantly better performances only for a-ß2GpI IgG with all the immunoassays analyzed with the exception of Inova CliA Bio-Flash where we obtained the same performances with in-house and manufacturer's cutoffs. CONCLUSIONS: By guidelines, all laboratories are strongly advised to validate/verify the manufacturer's cutoff values. We recommend establishing low-positive, medium-/high-positive, and high-positive CliA IgG aCL and a-ß2GpI ranges in order to help clinicians in the diagnosis and treatment of APS.

Patients with antiphosholipid syndrome and thrombotic recurrences: A real world observation (the Piedmont cohort study).

BACKGROUND: Patients with antiphospholipid syndrome (APS) often have thrombotic recurrences, sometimes despite appropriate ongoing anticoagulant treatment. Identifying APS vascular patients at high risk for thrombotic recurrences is still an unsolved issue. OBJECTIVES: To report the real-life experience of thrombotic recurrences in APS patients included in the Piedmont observational cohort study, and evaluate clinical and laboratory risk factors for thrombotic recurrences. PATIENTS: A multi-centre observational study was performed by enrolling 177 patients with vascular APS (primary APS in 99 subjects (56%)); the median follow-up was five years (range 1-26 years). RESULTS: The observed thrombotic recurrence rate was about 7.5/100 patient years in the first five years after the first thrombotic event. While the first recurrence often occurred (45%) in patients who were not on oral anticoagulant therapy (OAT), the second recurrence mainly occurred despite ongoing OAT (80%). However, due to the real-life observational nature of this study, treatment was based on the treating physician's judgement, and no structured therapeutic protocol was applied. Moreover, compliance with OAT was not available. No differences in antiphospholipid antibodies (aPL) profile were observed between patients with or without thrombotic recurrences, but a high risk aPL profile (Miyakis type 1 and 2a) was present in 96% of our patients, 26% of whom had triple positivity. Diabetes (p < 0.01, OR 10), inherited thrombophilia (p < 0.0078, OR 4) and OAT withdrawal were independent risk factors for recurrences. CONCLUSIONS: With the limit of a real-life observational cohort study, the thrombotic recurrence rate in APS was as high as 7.5/100 patient years in the first five years after the first thrombotic event. OAT discontinuation, diabetes and inherited thrombophilia, when associated with a high-risk aPL profile, are risk factors for thrombotic recurrences.

Thrombotic recurrences and bleeding events in APS vascular patients: a review from the literature and a comparison with the APS Piedmont Cohort.

In APS vascular patients, thrombotic recurrences are more frequent than in non-APS thrombotic patients. To better define this clinical setting, a systematic review of the literature after 1999 was performed: 8 cohort studies (including the recent APS Piedmont Cohort) and 6 intervention studies were selected and evaluated. Thrombotic recurrences, bleeding events, therapeutic strategies, antiphospholipid (aPL) profile, inherited and acquired risk factors (when present) were calculated and compared. Emerging risk factors for thrombotic recurrences include withdrawal of oral anticoagulant therapy (OAT), high intensity OAT (INR range 3-4), aPL profile (triple positivity, Miyakis types 1 and 2a profiles) and association with inherited or acquired pro-thrombotic risk factors. Moreover, there are evidences that high risk (mainly for aPL profile) APS vascular patients have a high recurrence rate in spite of correct OAT treatment. Clinical trials in this clinical setting are needed.

Primary prevention in antiphospholipid antibody carriers.

The discovery of antiphospholipid antibodies (aPL) positivity in individuals who have never experienced thrombosis or pregnancy complications is not a rare event, and is one of the unresolved issues in the field of antiphospholipid syndrome (APS). This paper focuses on primary prophylaxis for thrombotic events in aPL carriers. In our view, patients with high risk aPL profiles and/or other cardiovascular risk factors, concomitant diagnosis of systemic lupus erythematosus (SLE) and patients with an history of obstetric APS (OAPS) should be offered thromboprophylaxis. Chronic thromboprophylaxis with low-dose aspirin and hydroxychloroquine in aPL positive SLE patients should be prescribed both to prevent thrombosis and to avoid early organ damage.

Anti-cardiolipin and anti-ß2-glycoprotein I antibodies: normal reference ranges in northwestern Italy.

Laboratory tests for anticardiolipin antibodies (aCL) and anti-ß2glycoprotein I antibodies (a-ß2GPI) face problems common to many autoantibody assays: the lack of a reference standard and the need for each laboratory to assess assay-specific cut-off values. The aims of the study were to evaluate the reference range upper limits (99th percentile) used for aCL and a-ß2GPI in the northwest of Italy and to investigate the analytical performances of these assays with the newly obtained reference ranges. We assayed aCL and a-ß2GPI in 104 serum samples from patients without a history of thrombosis, pregnancy morbidity, tumours, infections and/or autoimmune diseases (30 males and 74 non-pregnant females). We tested all the commercial assays available in our regions (i.e. Orgentec Diagnostika, Aesku Diagnostics and Inova Diagnostics ELISA; CliA Zenit-RA and EliA Phadia Laboratory Systems). A further 30 serum samples, including 10 from healthy subjects, 10 from antiphospholipid syndrome (APS) patients and 10 from septic patients were assessed to investigate the analytical performance of the obtained cut-off limits. Reference range upper limits obtained with the commercial kits differ among assays and from the values reported by the manufacturer. Moreover, normal reference ranges calculated for IgG and IgM aCL differed from the arbitrary selected laboratory classification values suggested in the guidelines of 40 GPL and MPL.

Antiphospholipid syndrome in northwest Italy (APS Piedmont Cohort): demographic features, risk factors, clinical and laboratory profile.

We report the experience from the Antiphospholipid Antibodies (aPL) Regional Consortium in northwest Italy, meant to support clinical research and foster collaboration among health professionals regarding the diagnosis and management of antiphospholipid syndrome (APS) patients. This cohort-study (APS Piedmont Cohort) was designed to register the clinical characteristics at inception and associated immunological manifestations at diagnosis (if any) of patients who strictly fulfilled the current criteria for APS, all recruited at the Piedmont and Valle d'Aosta regions. Clinical and laboratory data from 217 APS patients (171 with vascular events, 33 with pregnancy morbidity and 13 with both), from 16 centres within the geographical area were collected. Venous thrombosis was recorded in 45.6% of patients, arterial thrombosis in 35%, small-vessel thrombosis in 1.12% and mixed arterial and venous thrombosis in the remaining 19.4% of the cases. Pregnancy morbidity included 19 patients with unexplained fetal death beyond the 10th week of pregnancy, 17 with premature birth before the 34th week and 10 with three or more unexplained spontaneous abortions before the 10th week of gestation. This consortium represents an instrument by which to audit clinical practice, to provide counselling to local centres and to sustain future basic and clinical APS research.

Failure of intravenous immunoglobulin to prevent congenital heart block: Findings of a multicenter, prospective, observational study.

OBJECTIVE: Congenital heart block (CHB) is presumed to be caused by transplacental passage of maternal immunoglobulin against Ro and La ribonucleoproteins. The recurrence rate in subsequent pregnancies following the birth of a child with CHB is approximately 19%. The purpose of this study was to determine whether intravenous immunoglobulin (IVIG) therapy could prevent the development of CHB in the fetuses of high-risk pregnant women. METHODS: A total of 24 pregnancies in 22 women who had a previous pregnancy in which CHB developed, were over the age of 18 years, were <12 weeks pregnant, and had anti-Ro, anti-La, or both antibodies were monitored in this multicenter, prospective, observational study. Fifteen patients received infusions of IVIG. The 9 pregnancies in the remaining 7 patients served as controls. IVIG was administered at a dose of 400 mg/kg at weeks 12, 15, 18, 21, and 24 of pregnancy. Echocardiograms were performed at least every 3 weeks from week 15 to week 30 of gestation. Electrocardiograms were obtained at birth. The outcome measure was the development of third-degree CHB detected by fetal echocardiogram. RESULTS: CHB developed in 3 babies among the 15 pregnancies in the treatment group (20%) and in 1 baby among the 9 pregnancies in the control group (11%). CHB was detected at weeks 18, 23, and 26, respectively, in the 3 babies in the treated group and at week 19 in the baby in the control group. Three of the affected pregnancies ended in termination; 2 for reasons related to the fetal disease and 1 for reasons related to both maternal (severe pulmonary hypertension) and fetal disease (at 21 weeks of gestation). CONCLUSION: IVIG at the dose and frequency used in this study was not effective as prophylactic therapy for CHB in high-risk mothers.

Neonatal lupus in triplet pregnancy of a patient with undifferentiated connective tissue disease evolving to systemic lupus erythematosus.

Pregnancy in patients suffering from undifferentiated connective tissue disease (UCTD) represents a risk situation for both the mother and the child. SSA/SSB autoantibodies can determine neonatal lupus (NL) in the foetus, regardless of the maternal disease. Furthermore, pregnancy increases the risk of flares and evolution to differentiated connective tissue disease (CTD). We report an uncommon case in which these complications occurred in a mother and in her foetuses. A 37-year-old woman affected by UCTD developed systemic lupus erythematosus (SLE) after her triplet pregnancy. The only manifestation of neonatal lupus we observed in the three newborns was SSA positivity associated with asymptomatic transient neutropenia.

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 > or =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.

Coeliac disease associated with Sjögren's syndrome, renal tubular acidosis, primary biliary cirrhosis and autoimmune hyperthyroidism.

Although coeliac disease may occur in patients affected by another immune-mediated disorder, its coexistence with multiple autoimmune diseases is not frequently described. We report here the case of a 45-year-old woman referred to our centre because of diarrhoea and weight loss, who had already received a diagnosis of primary biliary cirrhosis, Sjögren's syndrome and renal tubular acidosis. Following the development of diarrhoea we established the diagnosis of coeliac disease, based on the presence of anti-endomysium antibodies and a compatible duodenal biopsy. Despite gluten withdrawal she went on to develop an autoimmune hyperthyroidism. The patient tested positive for HLA DRB1*03 and DQB1*02. The association is unlikely to be casual and may be explained by autoimmune mechanisms, genetic susceptibility and favouring environmental factors commonly shared by the diseases of our patient.

The possible role of autoimmunity in the pathogenesis of diabetes in B-thalassemia major.

OBJECTIVE: To evaluate the possible role of autoimmunity in the pathogenesis of diabetes associated with B-thalassemia, we studied a cohort of 53 B-thalassemic individuals, under long term blood transfusion, that included twelve patients with diabetes (22.6%). MATERIAL AND METHODS: To evaluate the activation of an autoimmune response, individuals were tested for islet cell antibodies (ICA), glutamic acid decarboxylase (GAD) autoantibodies, insulin autoantibodies (IAA) and serum anti-nuclear antibodies (ANA). RESULTS: Nine of the total B-thalassemic population (16.98%) were ICA-positive. The frequency of ICA-positive subjects among thalassemic individuals was higher than in the general population. Five (41.6%) of the ICA-positive individuals were diabetic. Of these, three were serum C-peptide-negative (<0.21 nmol/l). HLA class II typing of our thalassemic population did not reveal significantly different allelic frequencies with respect to the control population. CONCLUSIONS: Our study demonstrates evidence of immune system activation against pancreatic B-cells in B-thalassemia and we propose that iron deposition may, through oxidative damage, act as an environmental factor that triggers the autoimmune response. Therefore, we speculate that pancreatic autoimmunity may contribute to selective B-cells damage in the pathogenesis of diabetes associated with B-thalassemia.

Analysis of T-cell clones in systemic lupus erythematosus.

BACKGROUND AND OBJECTIVE: It is fairly well established that T-helper (TH)((1)) cells play a role in the pathogenesis of organ-specific autoimmune diseases, while their role and their relationship with TH((2)) cells is far from being defined in systemic lupus erythematosus (SLE). To address this issue, six female patients who fulfilled the American Rheumatism Association criteria for the diagnosis of SLE were studied. DESIGN AND METHODS: We analyzed the intracellular production of cytokines by T-cells from the peripheral blood (PB). Then, we established T-cell clones (TCC) from the peripheral blood (PB) of all cases as well as from the synovial fluid of one patient with an articular flare-up. RESULTS: The percentages of IL-4 positive and IFN-g positive PB T-cells were not different between SLE patients and normal controls. When 93 TCC (67 CD4(+), 23 CD8(+)) from the PB of 5 different SLE patients were compared to 118 TCC (94 CD4(+), 23 CD8(+)) from 5 healthy controls no statistical difference was observed between SLE and controls in terms of TH((1)), TH((2)) or TH((0)) phenotype. However, SLE clones showed a reduced ability to secrete IL-10 (p = 0. 002). In contrast, the analysis of the 30 clones obtained from synovial fluid revealed that 11/23 CD4(+) clones were TH((1)), 12/23 were TH((0)), 2/7 CD8(+ )clones were TH((1)) and 5/7 were TH((0)). No TH((2)) clones were obtained from the synovial fluid. INTERPRETATION AND CONCLUSIONS: The data suggest that the T-cell subsets operating in actively inflamed organs of SLE may belong to the TH((1)) and TH((0)) subsets.

Increased nitric oxide in exhaled air of patients with systemic lupus erythematosus.

OBJECTIVE: In experimental animals, elevated nitric oxide (NO) production has been implicated in the pathogenesis of a lupus-like syndrome. Abnormalities of lung function tests are reported in a high proportion of patients with systemic lupus erythematosus (SLE). We investigated whether NO output in exhaled air might be increased in patients with SLE and whether it is related to disease activity and to respiratory function abnormalities. METHODS: Lung volume, maximal expiratory flow at 50 and 25% of vital capacity (MEF50 and MEF25), diffusion coefficient for carbon monoxide (KCO), and NO in the exhaled air were measured in 27 outpatients with SLE (23 women, age 39.2 +/- 16.3). NO in exhaled air was also measured in 30 healthy control subjects. Disease activity was assessed by the European Consensus Lupus Activity Measurement (ECLAM) scoring system. RESULTS: Mean values of peak concentrations of NO exhaled air were 64.8 +/- 27.9 parts per billion (ppb) in patients and 31.6 +/- 7.7 ppb in controls, p < 0.001. Peak NO concentration was directly related to ECLAM activity score (p < 0.05) and inversely related to MEF25 (p < 0.05). CONCLUSION: NO in exhaled air is significantly increased and correlated with disease activity in patients with SLE. Whether increased NO output depends on respiratory tract inflammation, as the relationship with MEF25 may suggest, or on circulating cytokines produced elsewhere remains to be investigated.

Anemia of chronic disorders in systemic autoimmune diseases.

BACKGROUND AND OBJECTIVE: Anemia of chronic disorders (ACD) is a mild to moderate anemia characterized by decreased serum iron, decreased total iron-binding capacity and increased iron stores that occurs in a wide variety of diseases including cancer, chronic infections and inflammatory disorders. The reason for this review is two-fold. First, systemic autoimmune diseases are frequently characterized by ACD. Second, advances in our knowledge of the pathophysiology of systemic autoimmune diseases as well as pathogenesis and treatment of ACD have so far been dealt with separately. Consequently, the approach to the evaluation of ACD in systemic autoimmune disorders has usually been either immunology- or hematology-oriented. The aim of this review is to integrate the pertinent information from both these fields in order to arrive at a more complete understanding of a problem common to hematologists and immunologists. INFORMATION SOURCES: The articles reviewed have been published in journals listed in the Science Citation Index and Medline. In addition, the authors have a vast experience in the field of hematology and are actively working in the field of systemic autoimmune disorders. STATE OF ART AND PERSPECTIVES: ACD is a parameter of disease activity in systemic autoimmune diseases. The severe inflammatory stimuli responsible for the pathophysiology of these disorders lead to several systemic changes (referred to as chronic active phase response) through which the organism tries to cope with chronic tissue injuries. These reactions are brought about by inflammation-associated cytokines, like IL-6, IL-1, TNF alpha, TGF beta that regulate hepatic synthesis of acute phase proteins. Many cytokines involved in chronic acute phase response, including IL-1, TNF alpha, TGF beta, have an inhibitory activity on erythroid colony formation in vitro. In addition, circulating TNF alpha is elevated in rheumatoid arthritis (RA), IL-1 beta serum levels are significantly increased in RA with ACD and RA patients treated in vivo with antibodies (Abs) to TNF alpha show disease improvement, including an increase in Hb values. Reduced erythropoietin (EPO) activity, usually the result of reduced production, plays a role in the pathogenesis of ACD observed in systemic autoimmune diseases. Both the production and the action of EPO may fall under the control of IL-1 and IFN-gamma. The most controversial and stimulating aspect of the pathogenesis of ACD in systemic autoimmune disorders is the role of iron metabolism and nitric oxide (NO), which contributes to the regulation of iron cellular metabolism. Both iron deficiency and iron overload may influence the proliferation of B and T lymphocytes and differentially affect T helper (TH)-1 and TH-2 lymphocytes. Furthermore, TH-1 cytokines stimulate and TH-2-type cytokines inhibit NO production. For these reasons, cell-mediated immunity may be expected to have influence on NO synthesis and on the mechanisms leading to iron accumulation in the reticuloendothelial system.

Autoimmune phenomena and hepatitis C virus in lymphoproliferative and connective tissue disorders.

Since hepatitis C virus (HCV) infection is frequently detected in patients with lymphoproliferative or autoimmune disorders and since the virus may infect lymphocytes, the question is raised whether malignant transformation and autoimmune manifestations in the presence of HCV are HCV-related or merely fortuitous. A close association has been firmly established between HCV infection and essential type II mixed cryoglobulinemia (ECM), an indolent lymphoproliferative disorder characterized by cryoprecipitable immune-complexes (IC) that may evolve into classical non Hodgkin's lymphomas (NHL) retaining the ability to produce cryoprecipitable rheumatoid factor (RF). It is reasonable to consider HCV as one cofactor in lymphomagenesis, even if the precise pathogenetic relationship between HCV infection, the chronic presence of cryoprecipitable IC and the development of NHL have not been established yet. Several epidemiological studies have documented the ability of chronic HCV infection to favour the production of autoAb. It is not clear why only some patients with HCV infection develop autoAb, nor why the most frequent autoAb detected in HCV-infected subjects are cryoglobulins. Though a high prevalence of anti-HCV has been found in a variety of systemic and organ-specific autoimmune diseases, it is likely that several of these associations are fortuitous with the notable exception of membranoproliferative glomerulonephritis. As HCV can provoke or exacerbate inflammatory signs and cause the production of RF, it is reasonable to suspect that HCV infection may be able to trigger the development of some connective tissue diseases or to exacerbate their clinical course. Nonetheless, it is clinically prudent to conclude that the pathogenetic relationships of Sjögren syndrome, rheumatoid arthritis and polyarthritis with HCV infection are more likely to be regarded as mediated via the intermediate development of ECM.

High prevalence of autoimmune phenomena in hepatitis C virus antibody positive patients with lymphoproliferative and connective tissue disorders.

The aim of this study was to investigate whether hepatitis C virus (HCV) may perturb the immune system towards autoreactivity. We studied the relationship between the prevalence of anti-HCV and the presence of laboratory and/or clinical autoimmune features in 300 patients: lymphoid malignancies (167) and autoimmune disorders (connective tissue diseases 100; idiopathic thrombocytopenic purpura (ITP) 33). As a control, hepatitis B surface antigen (HBV) and anti-hepatitis B core antigen (anti-HBc) were related to the same parameters. Anti-HCV and anti-HBV were detected in 68/300 (22.6%) and 70/300 (24.6%) patients, respectively. HCV prevalence was 18% in lymphoproliferative disorders (anti-HBc 28.1%) and 26% in connective tissue disease (anti-HBc 16.3%). Among ITP cases, 12/33 (36.4%) were anti-HCV+ and 10/33 (30.3%) anti-HBc+. In 24/30 (80%) anti-HCV+ patients with lymphoproliferative disorders at least one serologic or clinical autoimmune abnormality was detected. To the contrary, only 10/45 (22.2%) anti-HBc+ patients with lymphoproliferative disorders had at least one serologic or clinical abnormality (P < 0.0001). A statistically significant correlation was observed between HCV prevalence and the number of autoimmune alterations in both lymphoproliferative and connective tissue disorders, which was not found for anti-HBc. These data suggest that HCV may skew the immune system toward the production of autoantibodies and also support the possibility that some cases of ITP may be linked to both HCV and HBV infection.