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R A Sinico

Publications and source records attributed to R A Sinico.

68 records · Page 4Linked to original sources

In vitro synthesis of IgM rheumatoid factor by lymphocytes from patients with essential mixed cryoglobulinemia.

Peripheral blood mononuclear cells (PBMC) from patients with Essential Mixed Cryoglobulinemia (EMC) were studied for their ability to synthesize polyclonal IgM and rheumatoid factor (RF) IgM in vitro. Our results indicate: that EMC-PBMC produce smaller amounts of polyclonal IgM but higher quantities of IgM-RF than normal PBMC after pokeweed mitogen (PWM) or Staphylococcus aureus activation, so that the IgM-RF to total IgM ratio is significantly greater in EMC than in normal cultures; that enriched EMC-B lymphocytes display a significantly higher spontaneous synthesis of IgM-RF than normal B lymphocytes and that the IgM-RF B cell clones are receptive to T cell regulation. Taken together these findings suggest an expansion of B cell clones committed to IgM RF production and the presence in peripheral blood of differentiated B lymphocytes capable of secreting IgM-RF in EMC.

Adult↗

Plasma exchange in the treatment of essential mixed cryoglobulinemia nephropathy. Long-term follow up.

Plasma exchange is increasingly used for management of Essential Mixed Cryoglobulinemia. However little is known about the long term effects of this treatment. Therefore we have reviewed the clinical and laboratory data of 20 patients with type II EMC who were followed for a mean of 24 months. 16 patients had renal involvement, which was characterized histologically in all of them: 9 had diffuse proliferative GN plus endoluminal "thrombi" in 6 and vasculitis in 5, 4 had lobular membranoproliferative GN and 3 had focal proliferative GN. 14 patients had renal failure and 13 had proteinuria greater than or equal to 2 g/24 hr. PE (combined with immunosuppressive drugs in 18) was performed for a mean of 18 procedures. The combined treatment induced prompt remission of extrarenal and renal involvement. Serum creatinine and proteinuria decreased significantly in all but 2 patients during the treatment (s. creatinine from 2.9 to 1.6 mg/dl; proteinuria from 3.5 to 1.6 g/24 hr). Analysis of long term follow up revealed that these effects were long lasting in all the cases. We conclude that PE should be used for EMC nephropathy whenever prompt remission is not obtained by conventional therapy especially in consideration of its long term beneficial effects.

Adult↗

[Prevalence and clinical significance of cathepsin G antibodies in systemic sclerosis].

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.

Adult↗

Contribution of immunofluorescence to the identification and characterization of anti-neutrophil cytoplasmic autoantibodies. The role of different fixatives.

OBJECTIVE: To study the sera from selected groups of antineutrophil cytoplasmic antibody (ANCA) positive patients by means of the indirect immunofluorescence test (ANCA-IIF) with different fixatives, in order to better discriminate among the various ANCAs (Ag-specificity and disease associations), especially those for which the antigen targets have not yet been identified. METHODS: Eighty pathological serum samples and 15 normal sera were evaluated. Pathological samples included sera from 30 ulcerative colitis (UC) ANCA positive patients, 30 P-ANCA/myeloperoxidase (MPO-ANCA) positive microscopic polyangiitis (MPA) patients, 10 C-ANCA/proteinase 3 (PR3-ANCA) positive Wegener's granulomatosis (WG) patients, and 10 antinuclear antibody (ANA) positive (ANCA negative) systemic lupus erythematosus (SLE) patients. ANCA were detected by IIF on ethanol, methanol and formalin-fixed granulocytes and by ELISAs specific for MPO, PR3, lactoferrin (LF) and bactericidal/permeability-increasing protein (BPI). Additionally, sera were tested for the presence of antinuclear antibodies on IIF. RESULTS: 96% of serum samples from UC patients, positive by IIF on ethanol-fixed granulocytes, became negative when tested on formalin-fixed neutrophil slides. On the contrary, 95% of sera from vasculitic patients showed a clear diffuse granular cytoplasmic pattern on the same substrate; sera from all 10 SLE patients did not show any reactivity when formalin was used as fixative. On methanol-fixed neutrophils, 100% of UC P-ANCA positive sera were positive with the same pattern versus only 20% of vasculitic P-ANCA positive (MPO positive). Methanol fixation had no effect on PR3-ANCA and ANA positive sera. CONCLUSION: The comparison of IIF patterns of sera tested on different fixed cells may be useful to distinguish vasculitis-related P-ANCA versus ANA and vasculitis-related P-ANCA versus UC-related P-ANCA.

Antibodies, Antineutrophil Cytoplasmic↗

[ANCA-associated vasculitis].

ANCA-associated vasculitis. The term "antineutrophil cytoplasm antibody (ANCA)- associated vasculitis" (AASV) ihighers generally used to include primary vasculitis syndromes in which circulating ANCA against proteinase 3 (PR3) and myeloperoxidase (MPO) are commonly found. AASV syndromes include Wegener's granulomatosis, microscopic polyangiitis, idiopathic pauci- immune necrotizing crescentic glomerulonephritis and Churg-Strauss syndrome (CSS). AASV syndromes share some general clinical-histological manifestations, such as rapidly progressive renal failure and focal necrotizing glomerulonephritis with extracapillary proliferation in the absence (or in the presence of modest) immunoglobulins deposits (pauci- immune). Untreated AASV follow a progressive course with a fatal outcome due to vital organ failure. The combination of cyclophosphamide and prednisone is now established as the treatment of choice for patients with AASV, but there is considerable debate over the duration of therapy and the best way to administer cyclophosphamide. Treatment of AASV can be divided into two phases: an induction of remission and a maintenance of remission phase. Patients with AASV and renal involvement (serum creatinine less than 500 ml/L or 5.6 mg/dl) should be treated with a combination of oral prednisone with gradual tapering and cyclophosphamide. Once remission is achieved, usually after 3-6 months, azathioprine should replace cyclophosphamide. It is not known for how long treatment should be continued but at least one year of treatment after remission is warranted. When serum creatinine is than 500 ml/L (5.6 mg/dl) and/or oliguria is present, the addition of methylprednisolone pulses and/or plasma exchange should be considered.

Antibodies, Antineutrophil Cytoplasmic↗

[Non SLE connective tissue diseases: general aspects and kidney].

Connective tissue diseases represent a group of heterogeneous disorders that share certain common features, including inflammation of the skin, joints and other structures rich in connective tissue, as well as altered immunoregulation patterns, including autoantibody production and cell-mediated immunity abnormalities. While certain distinct clinical entities can be defined, manifestations can vary considerably from patient to patient, and the overlap of clinical features between and among specific diseases is common. Genetic, environmental and sex hormonal factors are likely to be of pathogenic importance. Among these diseases, systemic lupus erythematosus is the most frequent, followed by systemic sclerosis or scleroderma (SSc), Sjogren's disease, polymyositis and dermatomyositis and mixed connective tissue disease. Systemic sclerosis involves multiple organs in a process consisting of disseminated sclerosis affecting all compartments. Prominent vascular lesions typify the renal lesions. Scleroderma crisis is a major complication of SSc, characterized by severe hypertension, rapidly progressive renal failure, thrombotic microangiopathy with hemolitic anemia and low platelet count: the prompt use of angiotensin-converting enzyme (ACE) inhibitors significantly increased the 1-yr survival rate from 15 to 76%. Sjogren's syndrome is an immunologic disorder characterized by progressive lymphocytic destruction of the exocrine gland, frequently resulting in symptomatic eye and mouth dryness. The interstitial lesions constitute the principal renal manifestations: interstitial infiltrates and small lymphocytes, which can be homogenous and massive. In polymyositis and dermatomyositis renal involvement is rare.

Connective Tissue Diseases↗

[The clinical immunology laboratory in diagnosis and monitoring of systemic lupus erythematosus and connective tissue diseases].

The laboratory and particularly clinical immunology laboratories have an essential role in diagnosing and monitoring systemic lupus erythematosus (SLE), as well as other connective tissue diseases. The role of the clinical immunology laboratory in these diseases is to confirm or exclude diagnosis, to monitor disease activity, and to identify subgroup of patients. To obtain the best results in terms of diagnostic performance and clinical usefulness, the following recommendations should be fulfilled: anti-nuclear antibodies (ANA) determination by indirect immunofluorescence on Hep-2 cells is an effective screening assay in patients with clinical features of SLE. A negative ANA test makes the diagnosis of SLE unlikely. Anti-dsDNA antibodies are highly specific for SLE and are associated with renal involvement. The method of choice for anti-dsDNA is the Farr assay; however, the necessity of using radioactive materials reduces its applicability. As an alternative, immunofluorescence on Crithidia Luciliae can be used in the diagnostic phase due to its high specificity. The detection of antibodies to extractable nuclear antigens (ENA) and to phospholipids (lupus anticoagulant and anti-cardiolipin antibodies) is useful in identifying subgroups of patients at risk for some clinical manifestations. Anti-dsDNA measurement with a quantitative assay (the Farr assay or ELISA) is currently the best method to monitor disease activity along with complement levels. New assays (anti-C1q and anti-nucleosome antibodies) have been recently proposed for the diagnosis (anti-nucleosome) and monitoring of SLE patients (anti-C1q and anti-nucleosome antibodies), with promising results.

Algorithms↗

Anti-Ro/SSA antibodies in rheumatoid arthritis: clinical and immunologic associations.

OBJECTIVE: To assess the prevalence of anti-Ro/SSA in RA and to analyse clinical and serological features of anti-Ro/SSA positive patients with RA. METHODS: 195 consecutive patients affected by RA were studied by counterimmunoelectrophoresis and ELISA for the detection of anti-Ro/SSA antibodies. Anti-Ro were found in 12 patients, with a prevalence of 6%. These 12 patients were pooled with other 15 patients known to have anti-Ro/SSA antibodies and RA, in order to evaluate their clinical and laboratory features. RESULTS: Anti-Ro positive patients showed a common pattern of joint involvement at onset and a comparable progression of disease compared to anti-Ro negative subjects. In addition, extra-articular manifestations (such as xerophthalmia, xerostomia, scleritis, oral ulcers and amyloidosis) and peculiar autoantibody profile (hypergammaglobulinemia, anti-dsDNA and AMA) were found significantly associated to anti-Ro/SSA positivity. Even though DMARDs withdrawals were more frequently detected in anti-Ro/SSA patients, especially when using gold salts, no statistical difference between the two groups was detected. In addition, anti-TNFalpha treatment did not cause further progression of autoimmunity neither on laboratory nor on clinical ground. CONCLUSION: Anti-Ro/SSA can be detected in about 6% of patients affected by RA. These patients presented a peculiar clinical picture characterised by extra-articular manifestations some of which are known to be anti-Ro/SSA correlated, while others are more disease-specific (amyloidosis, episcleritis). Anti-Ro/SSA are significantly associated with other autoantibodies not specific for RA such as anti-dsDNA and AMA. Treatment with anti-TNF drugs did not cause further progression of autoimmunity neither on laboratory nor on clinical ground.

Amyloidosis↗

[New insights in the treatment of ANCA-associated systemic vasculitis].

The prognosis of untreated ANCA-associated systemic vasculitis (AASV) is poor with up to 90% of patients dying within 2 years. The combination of prednisone and cyclophosphamide is now established as the treatment of choice and leads to control of the disease in 80-90% of the patients. Such treatment has turned these acutely fatal diseases into chronic relapsing disorders with accumulating drug-related morbidity in over 50% of the patients, including diabetes, bladder and lympho-proliferative malignancy and infertility. Treatment of AASV can be divided into three phases: therapy for induction of remission, for maintenance of remission and therapy for refractory and relapsing disease. In addition, the treatment must be tailored to the stage and severity of the disease and a new classification of AASV was introduced: localized vasculitis, early systemic vasculitis, generalized vasculitis, severe renal vasculitis and refractory vasculitis. Different randomized clinical trials have been performed with the aim of optimizing the existing therapeutic regimens: some of these have been concluded, others are still ongoing. Newer therapeutic approaches are currently being tested and have involved the use of mycophenolate mofetil, anti tumour necrosis factor (TNF) drugs (anti TNF antibody infliximab and humanized soluble TNF receptor etanercept), monoclonal anti- lymphocyte antibody (anti-CD20). These new alternative therapies could be used in patients with frequent relapses, in patients who fail to achieve remission with standard induction therapy and in those with severe side effects due to cumulative doses of cyclophosphamide.

Antibodies, Antineutrophil Cytoplasmic↗

Significance of hepatitis C virus genotypes and viral load in patients with "essential" mixed cryoglobulinemia.

Several studies have established a strong association between hepatitis C virus (HCV) infection and essential mixed cryoglobulinemia (EMC). However, the mechanisms by which HCV infection may result in cryoglobulinemia in some patients but not in others remain unknown. In this paper we shall summarize some of the work done in our laboratories on certain aspects of HCV in patients with EMC.

Cryoglobulinemia↗

Cross-reactive idiotypes on cryoprecipitating monoclonal IgMk rheumatoid factors.

Shared idiotype specificities (CRIs) among monoclonal IgM rheumatoid factors from patients with essential mixed cryoglobulinemia have been demonstrated with the use of polyclonal antisera and have been confirmed, more recently, using monoclonal antibodies. In this paper we will summarize some of the work that has been performed in our laboratory using anti-idiotypic monoclonal antibodies. Such reagents allowed us to detect CRIs on cryoprecipitable rheumatoid factors, to detect idiotype-positive cells in bone marrow and peripheral blood, and to identify glomerular immune deposits.

Cross Reactions↗