The silica clotting time (SCT) is a phospholipid-dependent coagulation assay used for the laboratory diagnosis of lupus anticoagulant (LA) antibodies. The sensitivity and specificity of a new commercial SCT for identifying LA in patients who meet the clinical criteria for antiphospholipid syndrome (APS), and its association with thrombotic events were evaluated here. Forty-five patients who met the clinical criteria for APS according to the Sapporo International Consensus Statement were examined. Sixty-nine patients who did not meet the clinical criteria for APS, and 20 blood donors were used as controls. Plasma samples from the patients and controls were tested for LA using a new commercial SCT with low and high synthetic phospholipid concentrations. The results were compared with those obtained by diluted Russell's viper venom time (dRVVT) and activated partial thromboplastin time (APTT). SCT's sensitivity for identifying LA in patients who met the clinical criteria of APS was higher compared to APTT and dRVVT (53.3% vs. 31.1% and 31.1%), and the specificities of these assays were 96.6%, 100%, and 98.9%, respectively. When dRVVT was combined with SCT, and dRVVT was combined with APTT their sensitivities were 57.7% and 48.8%, and their specificities were 96.6% and 98.9%, respectively. A stepwise logistic regression analysis indicated that the combination of dRVVT with SCT was associated with total thrombotic events (odds ratio (OR) 5 11.5, 95% confidence interval (CI) 5 1.25-106.3, P 5 0.031) as well as with venous thrombosis (OR 5 4.09, 95% CI 5 1.16-14.43, P 5 0.028). According to our results, SCT is the most sensitive assay for identifying LA in patients who meet the clinical criteria for APS. Moreover, the highest sensitivity was reached with a combination of SCT and dRVVT. The method's association with total thrombotic events and venous thrombosis was in fact significant.

Objective: We evaluated the induction and clinical significance of ANA, anti-dsDNA and anti-ENA during infliximab therapy in patients with Rheumatoid Arthritis (RA) or Ankylosing Spondylitis (AS). Methods: We tested sera from 30 RA and 30 AS patients before and during treatment with infliximab. ANA and antidsDNA were determined by indirect immunofluorescence and anti-ENA by an “in house” counterimmunoelectrophoresis. Statistical analysis was performed by X2 and McNemar’s tests and U-test of Mann-Whitney. Results: Eight of the 30 RA patients and 1 of the 30 AS patients were positive for ANA before treatment with infliximab. Eighteen of the 22 (81.8%) negative patients with RA and 11 of the 29 (37.9%) negative patients with AS became positive for ANA during infliximab treatment. No ANA positive patients became negative during the therapy. The difference between ANA before and after treatment resulted significant in both RA and AS patients (p=0.001). The frequency of anti-dsDNA and anti-ENA did not change significantly from baseline, in both RA and AS patients. Acquired ANA positivity was not associated with clinical signs of lupus syndrome and was not correlated with adverse events. The mean values of ESR and CRP in RA patients who became positive for ANA were significantly decreased (p=0.01 and p=0.02 respectively). Conclusions: Infliximab treatment induced a significant increase in the frequency of ANA in RA and AS patients. The significance of ANA development in these diseases is at present unknown. The significant decrease of ESR and CRP in RA patients who became positive for ANA after treatment should be investigated in a larger number of patients

Objective: we proposed to determine the clinical significance of anti-NuMA and anti-HsEg5 antibodies in a group of patients affected with rheumatic diseases. Materials and methods: indirect immunofluorescence on HEp-2000 cells at serum dilution of 1:40 was used to examin 26 sera which had previously showed a “mitotic spindle” fluoroscopic pattern type during laboratory routine. Results: 21 sera (80,7%) were identified with NuMA and 5 (19,3%) with HsEg5 patterns alone or associated with other ANA patterns. However only patients with isolated positiveness and that is 15 with NuMA and 4 with HsEg5 stainings were included in this study. Of the NuMA positive patients 5 were affected with arthropathies associated to different forms of thyroiditis, 2 with seronegative arthritis, 2 with antiphospholipid syndrome, 1 with systemic lupus erythematosus (SLE), 1 with rheumatoid arthritis, 1 with sicca syndrome, 1 with undifferentiated connective tissue disease, 1 with Mycoplasma pneumaniae infection and 1 with retinal thrombosis. Of the HsEg5 positive patients 3 were affected with SLE and 1 with seronegative arthritis. Conclusions: NuMA does not prevail in any defined rheumatic disease, while HsEg5 staining were more frequent (75%) in patients affected with SLE all of whom showing high antibody titres

Objectives: To evaluate the prevalence and clinical significance of cathepsin G antibodies in patients affected with systemic sclerosis (SSc, scleroderma). Methods: 115 patients affected by SSc, 55 (47,8%) with diffuse scleroderma (dSSc) and 60 (52,2%) with limited scleroderma (lSSc), were tested for cathepsin G antibodies by ELISA method. Moreover these sera were evaluated by indirect immunofluorescence (IIF) on ethanol and formalin fixed human neutrophils. Results: By means of the ELISA method 16 (13,9%) patients were found to be sera positive for anti-cathepsin G, 2 (12.5%) of which showed a perinuclear fluorescence pattern (P-ANCA) and 4 (25%) an atypical ANCA staining, while 10 (62,5%) were negative on IIF. The IIF on scleroderma sera revealed 5 (4,3%) P-ANCA and 18 (15,7%) atypical ANCA patterns. The anti-cathepsin G antibodies significantly prevailed in scleroderma sera (p=0.02) when their frequency was compared with that of healthy controls; while they were not significantly associated to any clinical or serological features of SSc patients. Conclusions: The anti-cathepsin G antibodies were significantly frequent in scleroderma sera; however, no clinical correlations were found. Thus, the significance of their presence in SSc still needs to be clarified

Objective: This study aimed to evaluate the sensitivity and specificity of the anti-b2-glycoprotein I antibodies for pregnancy morbidity in the antiphosoplipid syndrome (APS). Methods: 335 women were recruited and on the basis of their clinical features were subdivided into 2 groups homogenous for number and age. The first (study) group contained the women whose pregnancy complications satisfied the classification criteria for APS. The second (control) group was made up of women with pregnancy complications not included in the classification criteria for APS. Anti-b2-GPI, anticardiolipin antibodies (aCL) and lupus anticoagulants (LA) were determined in all of these women. Results: The only antiphospholipid antibodies occurring with a significant frequency (p=0,00) in the women with pregnancy criteria for APS were the IgG anti-b2-GPI and the IgG aCL present respectively in 23,92% and in 27,60% of the women. Its association was found to be significant (p=0,000). The distribution of the different levels of positivity of the IgG and IgM anti-b2 GPI in the patients of the study and control groups was not significantly different. The highest sensitivity for pregnancy complications was that of the IgG aCL and of the IgG anti-b2 GPI whose difference was not statistically significant. The comparison of the specificity of the IgG and IgM anti-b2 GPI with that of the IgG and IGM aCL was not statistically significant. Conclusions: The importance of determining the IgG anti-b2 GPI as part of routine laboratory testing of women with pregnancy complications typical of APS was confirmed. Together with IgG aCL these antibodies have proved to be the most sensitive and specific markers of pregnancy complications in APS