Frequency Of Rheumatoid Factor Research Articles

Rheumatoid factor and anti-citrullinated protein antibodies (ACPA) in psoriatic arthritis (PsA), and skin psoriasis: Relevance and clinical implications

Aim of the workAnti-citrullinated protein antibodies (ACPAs), is a highly specific markers for rheumatoid arthritis, can also be found in psoriatic arthritis (PsA). This work aimed to look into the frequency of rheumatoid factor (RF) and ACPA in PsA and psoriasis patients without clinical evidence of arthritis (PSO), and to correlate findings with demographics, disease characteristics, laboratory findings, and radiological damage in PsA. Patients and methods: The study included 78 PsA patients, 47 PSO patients, and 69 normal controls. Full clinical assessments, RF and ACPA assays, and modified radiological Steinbroker score (Mss) for PsA were performed. Results: The age of the patients was 45.6 ± 8.7 years and the M:F 59:66 (M:F 0.9:1). Positive RF was not significantly different between PsA and PSO groups (p = 0.35), but positive ACPA was significantly more common in PsA patients (p < 0.001) than in PSO and controls. No significant difference was observed between the PSO and controls (p = 0.08). In PsA, RF titers correlated significantly with ESR (p = 0.002), swollen joint count (SJC)(p = 0.02), tender joint count (TJC)(p = 0.02), and mSS (p = 0.001), while in the PSO RF correlated significantly with ESR (p = 0.011) and CRP levels (p = 0.02). In the PsA, ACPA titer significantly correlated with CRP levels (p < 0.001), SJC (p = 0.002), TJC (p = 0.003), mSS (p < 0.001) and PASI (p < 0.001), but with none of these in the PSO. Conclusion: PsA patients have more frequent positive RF and ACPA than PSO patients. ACPA values are significantly correlated with markers of inflammation, swollen and tender joint count and radiological damage in PsA and not in PSO patients.

Anticentromere antibody positive patients with primary Sjögren's syndrome have distinctive clinical and immunological characteristics.

To investigate the clinical manifestations, immunological characteristics, circulating lymphocyte subsets and risk factors of anticentromere antibody (ACA) positive patients with primary Sjögren's syndrome (pSS). Data of 333 patients with newly diagnosed pSS were collected and analysed retrospectively. The demographic features, glandular dysfunction, extraglandular manifestations, laboratory data, peripheral blood lymphocyte profiles and serum cytokines were compared between ACA-positive and ACA-negative pSS patients. Logistic regression analysis was used to evaluate the association between ACA and pSS characteristics. The prevalence of ACA among pSS patients was 13.5%. ACA-positive pSS patients were older at diagnosis and had longer disease duration. Xerostomia, xerophthalmia, parotid enlargement, Raynaud's phenomenon (RP), lung and digestive system involvement were more common in ACA-positive group, whereas haematological involvement such as leukopenia was more common in the ACA-negative group. Less frequency of rheumatoid factor, hypergammaglobulinaemia, anti-SSA and anti-SSB positivity, as well as higher positivity rate of ANA were observed in ACA-positive pSS patients, who exhibited a lower ESSDAI. In addition, decreased B cells and elevated NK cells were found in ACA-positive patients. Multivariate analysis identified that disease duration longer than 5 years, parotid enlargement, normal immunoglobulin and the absence of anti-SSA antibody were risk factors of ACA-positive pSS. ACA positive pSS patients have distinctive clinical manifestations and less severe immunological features, present a lower disease activity and lower activation of the humoral immune system. Physicians should pay attention to RP, lung and liver involvement in this subset of pSS.

Association of rheumatoid arthritis and its severity with human leukocytic antigen-DRB1 alleles in Kurdish region in North of Iraq

BackgroundRheumatoid arthritis is a complex multifactorial chronic disease, the importance of human leukocytic antigen (HLA) as a major genetic risk factor for rheumatoid arthritis was studied worldwide. The objective of this study is to identify the association of HLA-DRB1 subtypes with rheumatoid arthritis and its severity in Kurdish region.MethodsA case–control study recruited 65 rheumatoid arthritis patients and 100 healthy individuals as control group all over the Kurdistan region/Iraq. Both patient and control groups are genotyped using polymerase chain reaction with sequence specific primer. Anti-CCP antibodies were measured by ELISA test. Rheumatoid factor, C-reactive protein, and disease activity score 28 which measured by DAS-28 values were calculated. The DAS-28 was used to assess the clinical severity of the patients.ResultsHLA-DRB1-0404 and HLA-DRB1-0405 frequencies showed a strong association with disease susceptibility (P < 0.001). The frequency of HLA-DRB1-0411 and HLA-DRB1-0413 were significantly higher in control group (P < 0.001). The frequency of rheumatoid factor and Anti-CCP were significantly higher among shared epitope-positive patients compared to shared epitope-negative patients (P < 0.001). Regarding the disease activity by DAS-28, rheumatoid arthritis patients didn’t show significant difference between the shared epitope-positive and shared epitope-negative patients.ConclusionsHLA-DR0404 and HLA-DR0405 alleles are related to RA, while HLA-DR1-0411 and HLA-DRB1-0413 protect against RA in the Kurdistan region in the North of Iraq.

Comparative characteristics of the clinical and laboratory features of the primary Sjogren’s syndrome associated with anticentromere antibodies and the “classic” subtype of the disease

Objective: to compare clinical and laboratory manifestations in 2 groups of patients with primary Sjogren’s syndrome (pSS): with and without anticentromere antibodies (ACA); compare the incidence, clinical and laboratory characteristics of lymphomas in these two groups.Materials and methods. We examined 119 patients with ACA-positive pSS (pSS-ACA+). pSS was diagnosed based on Russian 2001 criteria, systemic sclerosis (SSc) – criteria ACR/EULAR 2013. To diagnose liver diseases, the level of transaminases, alkaline phosphatase and antimitochondrial antibodies (AMA) was determined, as well as liver biopsy. The diagnosis of primary biliary cholangitis (PBC) was established according to the recommendations of the American Association for the Study of Liver Diseases, the Russian Gastroenterological Association and the Russian Society for the Study of the Liver. Lymphomas were diagnosed according to histological, immunohistochemical and molecular studies of affected organs biopsies, according to the classification of the World Health Organization. A combination of pSS and SSc was diagnosed in 37 patients, and they were excluded from further analysis. We compared clinical and laboratory features in patients with pSS-ACA+ (n=82) and ACA-negative pSS (pSS-ACA–, n=64) and characterized lymphomas in the pSS-ACA+ (n = 14) and pSS-ACA– (n=10) groups.Results and discussion. In patients with pSS-ACA+, a later age of disease onset was revealed, the duration of the disease before lymphoma development did not differ. In patients with pSS-ACA+, we found a lower frequency of rheumatoid factor (RF), antibodies to Ro (anti-Ro) and La (anti-La), decreased C3-complement, hypergammaglobulinemia, increased IgG concentration, CRP, increased ESR, leukopenia and anemia. 51.2% of patients with pSS-ACA+ were seronegative for anti-Ro, anti-La and RF. Patients with pSS-ACA+ had a higher frequency of AMA and elevated IgM. The incidence of cryoglobulinemia and paraproteinemia did not differ. The frequency of recurrent parotitis in pSS-ACA+ was significantly lower, there were no differences in the frequency and severity of other signs of salivary and lacrimal gland damage. PBC and epitheliitis of the biliary ducts in patients with pSS-ACA+ were detected significantly more often. Damage to the peripheral nervous system, lungs, hypergammaglobulinemic purpura, arthralgia and autoimmune thyroiditis were significantly more often detected in the group of patients with pSS-ACA–. In the pSS-ACA+ group, Raynaud’s phenomenon was significantly more frequent, mainly with scleroderma-type capillaroscopic abnormalities. There was no difference in the frequency of other signs characteristic of SSc. MALT lymphomas were diagnosed in the study groups with the same frequency. Patients with lymphomas in the pSS-ACA+ group were characterized by significantly higher laboratory activity. All patients with lymphomas in both groups showed persistent parotid salivary gland enlargement. Lymphomas in both groups developed in patients with late stage salivary and lacrimal gland damage, systemic manifestations of pSS in both groups were rare.Conclusion. pSS-ACA+ is an independent subtype of pSS, which has a number of significant clinical and laboratory differences from the “classic” variant of the disease. ACA in pSS are associated with a low frequency of anti-Ro, anti-La, and RF, as well as an increased risk of PBC and limited SSc. MALT lymphomas in the pSS-ACA+ and pSS-ACA– groups developed with the same frequency and were associated with the progression of glandular damage, regardless of the presence of systemic manifestations.

Latent rheumatic, thyroid and phospholipid autoimmunity in hospitalized patients with COVID-19

Autoimmune responses mediated by autoantibodies have been observed in SARS-CoV-2 infection. Herein, we evaluate the presence of rheumatic, thyroid and phospholipid autoantibodies in sera samples from 120 adult hospitalized patients with COVID-19 in comparison to pre-pandemic samples from 100 healthy individuals. In addition, to estimate the frequency of these autoantibodies in COVID-19, a meta-analysis of selected articles was conducted. Hospitalized patients with COVID-19 had latent autoimmunity characterized by a high frequency of anti-thyroid peroxidase antibodies, rheumatoid factor (RF), anti-cyclic citrullinated peptide third generation antibodies, antinuclear antibodies (ANAs), IgM anti-β2-glycoprotein I (β2GP1) and IgM anti-cardiolipin antibodies. The meta-analysis confirmed our results, with RF and ANAs being the most common autoantibodies. In addition, cluster analysis revealed that those patients with high frequency of RF, IgM anti-β2GP1 antibodies and ANAs had a longer hospital stay, required more vasopressors during hospitalization, and were more likely to develop critical disease. These data suggest that latent autoimmunity influences the severity of COVID-19, and support further post-COVID studies in order to evaluate the development of overt autoimmunity.

Clinical significance of serum B cell chemokine (CXCL13) in early rheumatoid arthritis patients

BackgroundThe diagnosis of early rheumatoid arthritis (RA) is challenging. B-cell chemokine (CXCL13) plays a critical role in the disease pathogenesis. Aim of the workTo assess the diagnostic value of serum CXCL13 in early RA and compare it with rheumatoid factor (RF) and anti-cyclic citrullinated peptide (anti-CCP) antibodies. Patients and methodsThe study included 60 RA patients; 30 early, 30 established RA and 30 healthy controls. The modified health assessment questionnaire (MHAQ), modified Sharp-van der Heijde score (MSS) and disease activity score (DAS28) were assessed in RA patients. RF, anti-CCP and serum level of CXCL13 were measured. ResultsPatients had a mean age of 39 ± 7.4 years and disease duration of 4.4 ± 5.7 years; they were 46 females and 12 males (F:M 3.8:1). Serum CXCL13 was significantly higher in early (191.7 ± 74.4 pg/ml) compared to established (136.4 ± 79 pg/ml) RA (p = 0.007) which were not observed with RF and anti-CCP; both were higher than in control (30.4 ± 13.5 pg/ml) (p < 0.001). In early RA, the frequencies of CXCL13, RF and anti-CCP positivity were 90%, 73.3% and 56.7% while in the established cases the frequencies were 36.7%, 66.7% and 63.3% respectively. CXCL13 significantly correlated with DAS28 (early: 0.49, p = 0.006; established: r = 0.38, p = 0.04) but not with MHAQ or MSS. The CXCL13 significantly correlated with both the RF and anti-CCP in both early and established cases (p < 0.001). ConclusionCXCL13 is an important for the diagnosis of early RA with a superior diagnostic performance compared to RF and anti-CCP. It may also be considered a potential biomarker of disease activity.

Association of STAT4 rs7574865 and PTPN22 rs2476601 polymorphisms with rheumatoid arthritis and non-systemically reacting antibodies in Egyptian patients.

The aim of this study was to investigate association of protein tyrosine phosphatase non-receptor type 22 (PTPN22) rs2476601 and signal transducer and activator of transcription 4 (STAT4) rs7574865 polymorphisms with rheumatoid arthritis (RA) susceptibility and to assess potential association with the status of rheumatoid factor (RF) and anti-cyclic citrullinated peptide (anti-CCP) antibodies, serum neopterin, and disease activity. RF, anti-CCP antibodies, and neopterin were assayed in serum of 100 unrelated RA patients and 114 controls. STAT4 rs7574865 G/T and PTPN22 rs2476601 C/T polymorphisms were genotyped by the TaqMan allelic discrimination method. The frequency of STAT4 variant allele was significantly higher in RA patients than in controls (p=0.01), while the variant allele of PTPN22 was identified in only two RA patients, in a heterozygous form and in none of control subjects. The frequency of STAT4 variant allele carrier genotypes (GT+TT) was significantly higher among RA patients than in controls (43.7 vs. 10.5%, p=0.02) and associated with RA under additive and dominant models. The frequency of RF and anti-CCP positivity was significantly higher among RA patients carrying T allele genotypes compared to patients carrying wild genotype (P=0.02 and 0.04, respectively). No significant associations between STAT4 variant and serum neopterin or disease activity parameters were identified. Our study confirmed the association of STAT4 rs7574865 polymorphism with RA and was the first to indicate an association with RF and anti-CCP antibodies positivity. We also found PTPN22 rs2476601 has no role in susceptibility to RA in Egyptian patients.

Collagen Autoantibodies and Their Relationship to CCP Antibodies and Rheumatoid Factor in the Progression of Early Rheumatoid Arthritis.

Serum autoantibodies to cyclic citrullinated peptides (anti-CCP) and rheumatoid factor (RF) are important markers for diagnosis and prognosis of rheumatoid arthritis (RA), but their autoantigens are not cartilage-specific. Autoantibodies to joint-specific type II collagen (CII) also occur in RA, and monoclonal antibodies of similar specificity induce collagen antibody-induced arthritis in animals, but their role in RA is uncertain. We utilized an enzyme-linked immunosorbent assay (ELISA) with the CB10 peptide of CII to compare the frequency of autoantibodies with those of anti-CCP and RF in stored sera from a prospective study of 82 patients with early RA to examine the outcome, defined as remission (n = 23), persisting non-erosive arthritis (n = 27), or erosions (n = 32). Initial frequencies of anti-CB10, anti-CCP and RF were 76%, 54%, and 57% in RA, and 4%, 0%, and 9% in 136 controls. The frequency of anti-CB10 was unrelated to outcome, but anti-CCP and RF increased with increasing severity, and the number of autoantibodies mirrored the severity. We suggest RA is an immune complex-mediated arthritis in which the three antibodies interact, with anti-CII inducing localized cartilage damage and inflammation resulting in citrullination of joint proteins, neoepitope formation, and a strong anti-CCP response in genetically-susceptible subjects, all amplified and modified by RF.

Rate of positive autoimmune markers in Human T lymphotropic virus type 1 carriers: a case-control study from Iran.

Human T lymphotropic virus type 1 (HTLV-1) infection with high prevalence in the north-east of Iran, particularly in Mashhad, can lead to adult T-cell leukemia (ATL) and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) and a variety of autoimmune diseases. The aim of the study was to examine the presence of autoimmune markers in HTLV carries. Serum samples were obtained from blood donors in Mashhad, northeastern Iran. One hundred and five HTLV-1 positive (cases) and 104 age- and sex-matched HTLV-1 negative donors (controls) were assessed for presence of serum autoimmune markers by enzyme-linked immunosorbent assay. The mean ages of cases and controls were 40.8 ± 9.4 and 41.5 ± 9.3 years, respectively (P = 0.5). In the case group, 81.9% and in the control group 83.7% were male (P = 0.74). The frequency of positive antinuclear antibodies and anticyclic citrullinated peptide antibodies in the serum of the two groups were not significantly different (P = 0.68 and P = 0.62, respectively). Only one antineutrophil cytoplasmic antibody-positive case (1%) was observed in the group and no anti-phospholipid immunoglobulin G positivity was observed. The frequency of rheumatoid factor (RF) was greater in case group than in the control group, although the difference was not significant (P = 0.08). The amount of RF in all 12 RF positive sera were higher than normal levels (33-37 IU/mL). Because we failed to detect any significant relation between serum autoimmune markers and HTLV-1 infection, and because of the relatively low prevalence of autoimmune diseases, it could be concluded that healthy HTLV-1 carriers do not produce rheumatologic-related auto-antibodies more than the healthy population.

Anti-CCP Antibodies and Rheumatological Findings in Brazilian Patients with Crohn's Disease

Background/Aims: Arthropathy is the most common extraintestinal manifestation observed in patients with Crohn's disease (CD). The present study aimed to screen rheumatoid arthritis (RA) using anti-CCP antibodies and rheumatoid factor (RF) in CD patients from Southern Brazil. Additionally, the presence of arthralgia and spondyloarthritis (SpA) was evaluated. CD patients, previously diagnosed using clinical data, imaging tests, endoscopic and histological findings, were included consecutively. Methods: A total of 100 patients participated in the study, of which 60% were female, with a mean age of 41.9 ± 12.04 (16-83 years). As controls, sera from 100 healthy individuals from the same geographic area were analyzed. Results: Arthralgias were present in 55% of the patients, being more frequent in women (65.5%; 36/55), than in males (34.5%). No association was found between arthralgia and the treatment method used. Six patients (6/100) had SpA previously diagnosed. In the CD group, anti-CCP was positive only in one patient, while RF was positive in 7 patients (7%; 7/100). The anti-CCP positive patient (woman, 38 years old, RF positive), fulfilled the ACR criteria and was diagnosed as RA. In the control group, anti-CCP antibodies were detected in 1% (1/100) and RF was positive in 6 of the samples (6%). Conclusion: Our data showed low frequency of anti-CCP antibodies and RF in Brazilian patients with CD. Additionally, we found a high prevalence of arthralgia in these patients, with 6% of them diagnosed with SpA.

Anti-citrullinated protein antibodies in rheumatoid arthritis: a bridge between genetic predisposition and autoimmunity

Anti-citrullinated protein antibodies in rheumatoid arthritis: a bridge between genetic predisposition and autoimmunity

The frequency of antibodies against cyclic citrullinated peptides and rheumatoid factor in healthy population: a field study of rheumatoid arthritis from northern turkey

Rheumatoid arthritis (RA) is a chronic, systemic and an autoimmune disease characterized by inflammation of the synovial membrane that affects approximately 1 % of the total world population. Rheumatoid factor (RF) is a widely used auto antibody in diagnosis of the RA and found positive in 50-80 % of the patients but with a lower specificity. On the other hand, anti-cyclic citrullinated peptide (anti-CCP) is the latest serological marker with a specificity around 98 %. This field survey was conducted in different regions to investigate the frequency of RF and anti-CCP and also frequency of RA in a northern province of Turkey. This study was conducted in 70 local areas (12 urban and 58 rural) in the province of Tokat, which is located in northern Turkey. The population of Tokat was reported to be 828,000 at the last census and about 530,000 individuals aged > 18 years old. The study population of 941 subjects (462 male and 479 female; urban 501 and rural 440) was selected by random sampling method among 530,000 individuals. Of the 941 healthy controls assigned to the study, 479 of them were female (51 %) and 462 of them were males (49 %), and median age of all participants was 41 ± 17. Twenty-six subjects were RF positive (2.8 %), and 9 patients were anti-CCP positive (1 %). The presence of both RF and anti-CCP antibodies has also been shown in two patients (0.2 %). In conclusion, we demonstrated that the frequency of RA was 0.53 %, RF presence was 2.8 %, and anti-CCP presence was 1 % in total 941 healthy subjects enrolled into study.

Clinical Sindbis Alphavirus Infection Is Associated With HLA-DRB1*01 Allele and Production of Autoantibodies

Sindbis virus (SINV) is a mosquito-borne alphavirus found in Eurasia, Africa, and Oceania. Clinical SINV infection, characterized by arthropathic disease that may persist for years, is primarily reported in Northern Europe where the disease has considerable public health importance in endemic areas. The aim of this study was to investigate the role of genetic factors in the susceptibility and outcome of SINV infection and to elucidate the association between SINV infection and autoimmunity. The study included 49 patients with serologically confirmed symptomatic SINV infection who were followed for 3 years after acute infection. Human leukocyte antigen (HLA) genes known to be associated with rheumatic and infectious diseases and complement C4 genes were determined in 35 patients. Furthermore, a set of autoantibodies was measured at the acute phase and 3 years after infection in 44 patients. The frequency of DRB1*01 was significantly higher among patients with SINV infection than in the reference population (odds ratio, 3.3; 95% confidence interval, 1.7-6.5; P = .003). The DRB1*01 allele was particularly frequent in patients who at 3 years postinfection experienced joint manifestations. The frequency of rheumatoid factor at 3 years postinfection was 29.5% and had increased significantly (P = .02) during the 3-year period. In addition, antinuclear and antimitochondrial antibodies were present in serum 3 years postinfection with frequencies of 15.9% and 6.8%, respectively. Our data show that symptomatic SINV infection is associated with the HLA system and that autoantibody titers are elevated in patients 3 years postinfection. These findings indicate that SINV-induced arthritis shares features with autoimmune diseases.

Antibodies to mutated citrullinated vimentin in patients with chronic hepatitis C Virus genotype IV infection-related arthropathy

One of the extra-hepatic manifestations of hepatitis C virus (HCV) infection is polyarthritis that mimics rheumatoid arthritis (RA). Anti-mutated citrullinated vimentin (MCV) was recently introduced in the diagnostic workup of RA, but its exact role in HCV infection and its related arthropathy is still unclear. The aim of the study is to determine the prevalence of anti-MCV antibodies in HCV-infected patients with or without articular involvement, and to investigate whether anti-MCV antibodies have an additional role to anticyclic citrullinated peptide (CCP) antibodies and rheumatoid factor (RF) in differentiating patients with RA from patients with HCV-related arthropathy. Fifty-five HCV-infected patients (HCV RNA positive) and 30 RA patients (fulfilling the American College of Rheumatology classification criteria for RA and negative for HCV) were included. Anti-MCV antibodies, anti-CCP antibodies, RF and cryoglobulins were measured. Articular involvement in hepatitis C patients was evaluated. Articular involvement was detected in 30/55 (54.5%) of HCV-infected patients. The most frequent pattern was symmetric polyarthralgias and the most frequent joints to be involved were the wrists, metacarpophalangeal joints, shoulders and knees. In HCV arthropathy, anti-MCV was positive in 9/30 (30%), anti-CCP in 0% and RF in 22/30 (73.3%). Whereas, in chronic HCV without arthropathy, anti-MCV was positive in 8 patients (32%), anti-CCP in one patient (4%) and RF in 23/25 (92.0%). There was no significant difference between the two HCV groups as regards the frequencies of anti-MCV (P = 0.89), anti-CCP (P = 0.93) and RF (P = 0.15). In RA, anti-MCV was positive in 93.3% anti-CCP in 96.7% and RF in 86.7%. There was no significant difference in RF between RA and HCV arthropathy (P = 0.33). Meanwhile, there was a highly significant difference between both groups regarding anti-MCV and anti-CCP (P < 0.0001 for each). The sensitivity of anti-MCV, anti-CCP and RF for RA was 93.3, 96.7 and 86.7%, respectively. Whereas their specificity was 69.1, 98.2 and 18.2%, respectively. In addition, the mean levels of anti-MCV and anti-CCP were significantly increased in RA than in all HCV patients (P = 0.038 and P < 0.0001, respectively). Meanwhile, there were no significant differences in mean levels of anti-MCV and anti-CCP between HCV patients with arthropathy and those without arthropathy (P = 0.11 and P = 0.73, respectively). Also, there were no differences in mean RF between both HCV groups. There was a significant positive correlation between anti-MCV and anti-CCP levels in patients with HCV-related arthropathy (r = 0.39, P = 0.032) and in those without arthropathy (r = 0.578, P = 0.002). Cryoglobulins were detected in 7/30 HCV-related arthropathy (23.3%) and were positively correlated with anti-MCV(r = 0.485, P = 0.007). Anti-CCP still attains the major role in differentiating RA from HCV arthropathy. Anti-MCV seems to play no additional role in this aspect. The role of mutation of vimentin in the pathogenesis of HCV arthropathy is not as clear as it is for RA and needs further investigation.

Anti-cyclic citrullinated peptide antibodies are not associated with familial Mediterranean fever

This study investigated the presence of anti-cyclic citrullinated peptide (anti-CCP) antibodies in familial Mediterranean fever (FMF) patients and controls. Forty-nine patients with FMF were enrolled (23 had a history of arthritis during attacks and 26 had no such history). Two control groups were enrolled: 20 patients with rheumatoid arthritis (RA) and 30 healthy individuals. Clinical and laboratory assessments of the FMF patients were performed during attack-free periods. Erythrocyte sedimentation rate (ESR), serum C-reactive protein (CRP), rheumatoid factor (RF), and anti-CCP antibody levels were measured. In RA patients' ESR and CRP levels, frequency of RF, and anti-CCP antibody levels were significantly higher than in both FMF patients and healthy controls (p 0.001). Moreover, anti-CCP was negative in all healthy controls as well as in all FMF patients. Our results show that anti-CCP antibodies are not associated with FMF.

IgM, IgG, and IgA rheumatoid factors in pigeon hypersensitivity pneumonitis

The association of rheumatoid factor (RF) and lung disease in several immunologically mediated conditions has suggested that it may be physiopathologically relevant. Since previous reports in hypersensitivity pneumonitis (HP) have dealt mainly with the immunoglobulin M (IgM) RF measurement, we studied such antibody activity in other immunoglobulins, to determine the IgG and IgA RF levels in pigeon-HP, and in asymptomatic breeders (AB) and rheumatoid arthritis (RA) as controls. RFs were measured in 35 HP patients, 41 AB, 31 RA controls, and 55 healthy donors by enzyme-linked immunosorbent assay (ELISA) using human or rabbit immunoglobulin G (IgG), anti-IgM, F(ab')2 of IgG, and IgA F(ab')2 conjugates. An affinity chromatography, fragment crystallizable (Fc) preparations of IgG, pepsin digestion, and Western blots were used to confirm RF specificity. We also evaluated anti-avian antibodies (AA) and cross-reacting antibodies. The HP group revealed positive IgM (51.4%), IgG (31.4%), and immunoglobulin A (IgA) (34.2%) RF tests, and these antibody values exceeded the AB reference levels (P<0.02). HP and RA showed a similar frequency and distribution of RFs. Possible immunoassay interferences were excluded. As in other immunologically mediated diseases, IgG and IgA RFs may play a pathogenic role in HP, amplifying the inflammatory reaction, immune-complex formation, and complement activation. IgM-RF producing cells that have been implicated in the presentation of self and foreign antigens, and T-cell activation might induce the isotype switching of RFs.

Systemic autoimmune diseases co‐existing with chronic hepatitis C virus infection (the HISPAMEC Registry): patterns of clinical and immunological expression in 180 cases

To describe the clinical and immunologic characteristics of a large series of patients with systemic autoimmune diseases (SAD) associated with chronic hepatitis C virus (HCV) infection. We analysed 180 patients diagnosed with SAD and chronic HCV infection seen consecutively at our centres during the last 10 years. The clinical and immunological patterns of disease expression were compared with 180 SAD-matched patients without chronic HCV infection. A total of 180 HCV patients fulfilled the classification criteria for the following SAD: Sjogren's syndrome (n = 77), systemic lupus erythematosus (n = 43), rheumatoid arthritis (n = 14), antiphospholipid syndrome (n = 14), polyarteritis nodosa (n = 8) and other SAD (n = 24). One hundred and thirty (72%) patients were female and 50 (28%) male, with a mean age at SAD diagnosis of 50 years. The main immunologic features were antinuclear antibodies in 69% of patients, cryoglobulinaemia in 62%, hypocomplementaemia in 56% and rheumatoid factor (RF) in 56%. Compared with the SAD-matched HCV-negative group, SAD-HCV patients presented a lower prevalence of females (P = 0.016), an older age at SAD diagnosis (P = 0.039) and a higher prevalence of vasculitis (P < 0.001) and neoplasia (P < 0.001). Immunologically, SAD-HCV patients presented a lower prevalence of antinuclear (P = 0.036), anti-extractable nuclear antigen (P = 0.038) and anti-DNA (P = 0.005) antibodies, and a higher frequency of RF (P = 0.003), hypocomplementaemia (P < 0.001) and cryoglobulins (P < 0.001). In comparison with an SAD-matched HCV-negative population, SAD-HCV patients were older and more likely to be male, with a higher frequency of vasculitis, cryoglobulinaemia and neoplasia. This complex pattern of disease expression is generated by a chronic viral infection that induces both liver and autoimmune disease.

An epidemiologic study of trends in prevalence of rheumatoid factor seropositivity in Pima Indians: evidence of a decline due to both secular and birth-cohort influences.

Previous population studies have suggested that both rheumatoid factor (RF) production and rheumatoid arthritis (RA) may be declining in occurrence, and both secular and birth-cohort influences have been implicated. Since Pima Indians have a very high incidence of RA and also have shown recent evidence of a decline in RA, this study evaluated the relative contributions of age, secular, and birth-cohort influences on RF seropositivity in the Pima Indian population. RF data, as assayed by both the bentonite flocculation test (BFT) and the sheep cell agglutination test (SCAT), were available on 5,345 Pima Indians born between 1886 and 1975, who were surveyed at biennial intervals between 1966 and 1995. An age-period-cohort analysis was conducted using data on 18,295 examinations undertaken during the period of study. There was a decline in the proportion of positive test results for RF (titer > or = 1:32) by both BFT and SCAT, in both male and female subjects from 1966-1975 to the later decades of the study (1976-1985 and 1986-1995). Across all periods, by both assays, the crude proportion of positive titers increased with increasing age of the subjects. There was a very clear birth-cohort effect: the highest likelihood of seropositivity was in those individuals born around the end of the nineteenth century, with continuing decline in seropositivity up to the most recent birth cohort. A logistic regression analysis, adjusting for Pima heritage and sex, demonstrated a substantially greater influence of birth cohort than of calendar year on the frequency of RF positivity. In the Pima Indian population, environmental influences in early life are important predictors of the lifelong likelihood of RF positivity. This may have implications for understanding the epidemiology and etiology of RA.

Reconstitution of peripheral blood lymphocyte subsets in the long-term disease-free survivors of patients with acute myeloblastic leukemia.

The number of long-term survivors of patients with acute myeloblastic leukemia (AML) has increased as a result of the progress of chemotherapy. We examined the recovery of peripheral blood lymphocytes (PBL) subset after chemotherapy to clarify the reconstitution of the immune system in AML. Thirty patients with AML in complete remission (CR) were entered into the study. There were 12 males and 18 females; one M0, six M1, 14 M2, three M3, two M4 and four M5 according to FAB classification. The age ranged from 21 to 78 years (median age, 46 years) and the duration of disease-free survival after completion of chemotherapy ranged from 5 to 122 months (median, 35 months). The chemotherapy was performed according to the protocol designed by the Japan Adult Leukemia Study Group (JALSG). PBL subsets were analyzed by flow cytometry with the use of monoclonal antibodies against CD2, CD3, CD4, CD5, CD8, CD16, CD20, CD45RA, CD56, CD57 and HLA-DR. There was a significant positive relationship between the absolute number of CD4+, CD45RA+ CD4+ cells and the duration of time post-therapy and a significant negative relationship between %CD5+ B, CD56+ cells and the duration of time post-therapy. The appearance of autoantibodies (rheumatoid factor and anti-DNA antibody) tended to increase after 2 years, however, there was no relationship between CD5+ B cells and the frequency of rheumatoid factor. These findings demonstrate that patients in CR have a low number of CD4+ and CD45RA+ CD4+ T cells at an early period after chemotherapy and that each subset recovered to a normal level in 2 years. %CD5+ B and CD56+ cells gradually decreased and returned to their normal level after 4 years. There were high numbers of DR+ T cells and NK cells for a long time, suggesting that activated T cells and NK cells may play a role in the immune surveillance system after chemotherapy.

High Prevalence of Rheumatoid Factor in Community-based Series of Patients with Rheumatoid Arthritis Meeting the New (1987) ARA Criteria: RF-negative non-erosive rheumatoid arthritis is very rare

The aim of the study was to assess the prevalence of rheumatoid factor (RF) in a community-based rheumatoid arthritis (RA) series. The subjects of the series represented prevalent RA cases in the Kuusamo community in Northern Finland with 13,000 adult inhabitants. The patients were selected from the official Finnish data registers and from among the subjects who had consulted the local general practitioners due to rheumatic complaints in the recent years, using the American Rheumatism Association (ARA) 1987 classification criteria for inclusion. For this study, ninety-five out of the 103 RA patients so found were RF-tested by immunoturbidimetry. At the time of the study, 71 (75%) of the 95 cases were RF positive, 83 (87%) being 'ever' positive (in one case the early RF status was unclear). Our result contrasts with the much lower prevalence figures (25-60%) obtained from the earlier cross-sectional population-based RA studies, which have used the ARA 1958 definite RA as the inclusion criterion of the subjects. All the eleven patients with RF-negative RA had erosive joint disease. The RF-negative RA patients had a significantly lower frequency of HLA-DR4 (18%) than the RF-positive ones (58%), p<0.05. We found a high frequency of RF among prevalent community-based RA cases meeting the ARA criteria. According to our results, RF-negative non-erosive RA is very rare among cases selected with the above methods.