A longitudinal study of antibody responses to selected host antigens in rheumatic fever and rheumatic heart disease.

Introduction. Group A streptococci can trigger autoimmune responses that lead to acute rheumatic fever (ARF) and rheumatic heart disease (RHD).Gap Statement. Some autoantibodies generated in ARF/RHD target antigens in the S2 subfragment region of cardiac myosin. However, little is known about the kinetics of these antibodies during the disease process.Aim. To determine the antibody responses over time in patients and healthy controls against host tissue proteins - cardiac myosin and peptides from its S2 subfragment, tropomyosin, laminin and keratin.Methodology. We used enzyme-linked immunosorbent assays (ELISA) to determine antibody responses in: (1) healthy controls; (2) patients with streptococcal pharyngitis; (3) patients with ARF with carditis and (4) patients with RHD on penicillin prophylaxis.Results. We observed significantly higher antibody responses against extracellular proteins - laminin and keratin in pharyngitis group, patients with ARF and patients with RHD when compared to healthy controls. The antibody responses against intracellular proteins - cardiac myosin and tropomyosin were elevated only in the group of patients with ARF with active carditis. While the reactivity to S2 peptides S2-1-3, 8-11, 14, 16-18, 21-22 and 32 was higher in patients with ARF, the reactivity in the RHD group was high only against S2-1, 9, 11, 12 when compared to healthy controls. The reactivity against S2 peptides reduced as the disease condition stabilized in the ARF group whereas the reactivity remained unaltered in the RHD group. By contrast antibodies against laminin and keratin persisted in patients with RHD.Conclusion. Our findings of antibody responses against host proteins support the multistep hypothesis in the development of rheumatic carditis. The differential kinetics of serum antibody responses against S2 peptides may have potential use as markers of ongoing cardiac damage that can be used to monitor patients with ARF/RHD.

Sentinel biomarkers in HCV positive patients with mixed cryoglobulinemia.

BACKGROUND: Infections, autoimmunity and cancer play a role as determinants of etiology in Hepatitis C virus (HCV) related mixed cryoglobulinemia (MC). Several factors of risk have been suggested as markers of pathogenesis and progression of HCV-related MC into B cell Non-Hodgkin's Lymphoma (B-NHL). Here, we evaluated IgG subclass distribution, free light chains (FLCs) and vascular endothelial growth factor (VEGF) as a new combination of biomarkers. METHODS: We measured IgG1-4 subclasses, FLCs and VEGF levels in sera 53 from HCV-related MC, in comparison with 40 sera from HCV negative patients with rheumatoid arthritis (RA) and 30 from healthy blood donors (HBD). RESULTS: IgG3 levels were significantly higher in HCV-MC patients with a decrement of IgG2 and IgG4; FLC levels significantly increased in both MC and RA patients' groups; serological VEGF was higher in HCV-MC patients than in HBD in correlation with k and λ levels. CONCLUSION: Our results suggest that a specific IgG subclasses pattern together with raised levels of FLCs and VEGF could represent the biomarker "signature" of an inflammation multistage of acquired immune system.

Value of serum procalcitonin for the diagnosis of bacterial septic arthritis in daily practice in rheumatology.

INTRODUCTION/OBJECTIVES: Septic arthritis is a diagnostic and therapeutic emergency because of a high morbidity and mortality. Nevertheless, the etiologic diagnosis is often difficult. The aim of our study was to determine if serum procalcitonin was a discriminatory biomarker in case of arthritis of undetermined etiology. METHOD: Patients were separated in five groups: gouty arthritis, calcium pyrophosphate deposition arthritis, osteoarthritis or post-traumatic arthritis ("mechanical" arthritis), chronic inflammatory rheumatic arthritis, and septic arthritis. Levels of serum white blood cells, C-reactive protein and procalcitonin were measured. RESULTS: Ninety-eight patients were included: 18 in the "gout" group, 26 in the "calcium pyrophosphate deposition arthritis" group, 16 in the mechanical group, 18 in the "chronic inflammatory rheumatic" group, and 20 in the "sepsis" group. The area under the receiver operating characteristic curve of white blood cells, C-reactive protein, and procalcitonin levels to diagnose a septic arthritis were 0.69 (IC95% 0.55-0.83), 0.82 (IC95% 0.73-0.91), and 0.87 (IC95% 0.76-0.98) respectively. For a cutoff of 0.5 ng/ml, procalcitonin sensitivity, specificity, positive predictive value, negative predictive value, positive likelihood ratio and negative likelihood ratio were 65%, 91%, 65%, 91%, 7.2, and 0.4, respectively. Serum C-reactive protein and procalcitonin levels were correlated, were not different in sepsis or gout groups, and were higher in non-septic arthritis with poly-arthritis than with mono-arthritis (p < 0.05). CONCLUSIONS: Serum procalcitonin is a useful biomarker in arthritis management with diagnosis performances higher than those of other biomarkers (white blood cells, C-reactive protein).Key Points• Diagnostic performances of serum procalcitonin level in septic arthritis are higher than those of serum C-reactive protein or white blood cells levels.• Serum procalcitonin levels are not different in septic arthritis or gouty arthritis.• Serum procalcitonin levels are higher in non-septic arthritis with poly-arthritis than with mono-arthritis.

A novel approach for characterizing variations in serum peptides in rheumatic heart disease.

BACKGROUND & OBJECTIVES: Acute rheumatic fever and rheumatic heart disease (RHD) are important public health problems in developing countries. In this study, peptidomic analyses on RHD patients and healthy individuals were performed to characterize variations in serum peptide levels using label-free quantitation approaches. METHODS: Blood samples were obtained from 160 healthy controls and 160 RHD patients. Of the 448 identified peptides, 272 were analyzed by two label-free mass spectrometry methods, the spectral count and spectral index. RESULTS: There were 38 proteins and 95 peptides with significant (adjusted P<0.001) differences in the abundance of peptides between healthy controls and RHD patients, including multiple peptides derived from histone H2B, villin-like protein, complement C4-B and motile sperm domain containing protein-2. The levels of 10 peptides were upregulated, and 85 peptides were downregulated in patients compared to controls. In addition, in patients, the levels of four proteins were upregulated and 34 were downregulated compared to controls. INTERPRETATION & CONCLUSIONS: This study shows that detection of significant changes in serum peptides reflects the difference between RHD patients and healthy controls. This label-free method may be helpful for clinicians to treat RHD patients during the perioperative period.

Plasma adiponectin levels and relations with cytokines in children with acute rheumatic fever.

AIM: We aimed to investigate the role of adiponectin in acute rheumatic fever by evaluating correlations with cytokines and acute-phase reactants. METHODS: Patients were divided into three groups by clinical findings. Group 1 included 8 patients with only chorea, Group 2 included 13 patients with arthritis and carditis, and Group 3 included 12 patients with only carditis. A total of 54 age- and gender-matched children were enrolled in the control group. Blood samples were drawn for analysing acute-phase reactants, adiponectin, tumour necrosis factor-α, interleukin-6, and interleukin-8 levels at baseline on Days 2, 5, 10, and 15, and at 8 weeks. RESULTS: There was no statistically significant difference between baseline age, gender, body mass index, serum triglyceride, total cholesterol, and low-density lipoprotein levels of the study and control groups (p>0.05). No correlation was found between baseline plasma adiponectin levels, age, body mass index, follicle-stimulating hormone, luteinising hormone, oestradiol, total testosterone, and blood lipid levels of the study and control groups (p>0.05). We found that adiponectin and interleukin-6 levels increased, tumour necrosis factor-α levels decreased, and interleukin-8 levels remained unchanged in acute rheumatic fever, which is an inflammatory disease. Moreover, adiponectin level was higher and tumour necrosis factor-α level was lower in the improvement period in comparison with the acute period, particularly in the carditis group. CONCLUSION: It was considered that, increasing throughout the treatment period, adiponectin may have anti-inflammatory effects in acute rheumatic fever. In addition, adiponectin levels are associated with a decline in inflammatory mediators in rheumatic fever.

New onset of dermatomyositis/polymyositis during anti-TNF-α therapies: a systematic literature review.

We performed a systematic search of databases from 1990 to 2013 to identify articles concerning the new onset of dermatomyositis/polymyositis (DM/PM) in patients treated with anti-TNF-α therapy. We retrieved 13 publications describing 20 patients where the new onset of DM/PM after anti-TNF-α therapy was recorded. 17 patients were affected by rheumatoid arthritis (RA), one by Crohn's disease, one by ankylosing spondilytis, and one by seronegative arthritis. In 91% of the cases antinuclear autoantibodies were detected after the introduction of anti-TNF-α therapy. In 6 patients antisynthetase antibodies were detected and other clinical findings as interstitial lung disease (ILD) were recorded. Improvement of DM/PM after anti-TNF suspension (with the concomitant use of other immunosuppressors) was recorded in 94% of cases. The emergence of DM/PM and antisynthetase syndrome seem to be associated with the use of anti-TNF-α agents, especially in patients with chronic inflammatory diseases (mainly RA) with positive autoantibodies before therapy initiation. In particular, physicians should pay attention to patients affected by RA with positive antisynthetase antibodies and/or history of ILD. In those cases, the use of the TNF-α blocking agents may trigger the onset of PM/DM or antisynthetase syndrome or may aggravate/trigger the lung disease.

Autoimmune endocrine disorders and coeliac disease in children and adolescents with juvenile idiopathic arthritis and rheumatic fever.

OBJECTIVES: There have been few studies on the association between childhood autoimmune and rheumatic diseases. Therefore, this study aims to assess the frequency of autoimmune thyroiditis (AT), coeliac disease (CD) and type 1 diabetes mellitus (T1DM) in children and adolescents with juvenile idiopathic arthritis (JIA) and rheumatic fever (RF). METHODS: This cross-sectional study includes 53 patients with JIA, 66 patients with RF and 40 healthy subjects controls. All subjects were evaluated for thyrotropin (TSH), triiodothyronine (T3), free thyroxine (FT4), antithyroglobulin (Tg) and antiperoxidase antibodies, fasting glucose, C-peptide, anti-glutamic acid decarboxylase (GAD), anti-islet cell (IA) and antitransglutaminase IgA (tTG) antibodies. Patients with thyroid dysfunction, positive anti-thyroid antibodies or tTG underwent thyroid ultrasonography and jejunal biopsy, respectively. RESULTS: In group 1 (n=53), 21 patients presented thyroid disorders (40%; 42% oligoarticular), either subclinical hypothyroidism (13%) or positive anti-thyroid antibodies (26%, 50% oligoarticular), significantly higher than in control group (p<0.009, OR=10.5, CI 1.29-85.2). In group 2 (n=66), thyroid disorders were identified in 11 patients, four (6%) with subclinical hypothyroidism and seven (11%) with positive anti-thyroid antibodies (p=0.06, compared with the control group). There were no cases of clinical overt hypothyroidism, positive anti-GAD or anti-IA, nor changes in serum C-peptide and glycemia. CD was confirmed in one patient from each group. CONCLUSIONS: Patients with JIA (especially the oligoarticular form) and RF should be investigated for thyroid dysfunction. Longitudinal studies could establish screening protocols for CD in patients with JIA and RF. The cost-effectiveness of T1DM screening is not justified in this population.

Association of circulating levels of MMP-8 with mortality from respiratory disease in patients with rheumatoid arthritis.

INTRODUCTION: Matrix metalloproteinases (MMPs) are implicated in the destruction of the joint and have been shown to be strongly associated with inflammation in rheumatoid arthritis (RA). Circulating MMPs have also been associated with cardiovascular disease in the general population, and are predictive of cardiovascular mortality. The purpose of the present study was to determine whether circulating levels of MMPs are predictive of mortality in RA. METHODS: A multiplex suspension array system (Luminex®) was used to measure levels of MMPs (1, 2, 3, 8 and 9) in sera taken at recruitment of RA patients (n = 487) in a study of factors associated with mortality in RA. Patients were tracked on the National Health Service Central Register for notification of death, and the relationship between baseline MMP levels and mortality was analysed using Cox proportional hazards regression analysis. RESULTS: At the time of follow-up, 204/486 patients had died, of which 94 (46.1%) had died of circulatory diseases, 49 of malignancy (24.0%), and 42 (20.6%) of respiratory diseases. In a stepwise analysis which included all MMPs, only MMP-8 was significantly associated with all cause mortality (P = 0.0007, 0.6% hazard ratio increase per ng/ml). No association was found between MMP levels and mortality due to circulatory disease or malignancy. However MMP-8 levels were strongly associated with mortality due to respiratory disease (P < 0.0001, 1.3% hazard ratio increase per ng/ml). The association with respiratory disease related mortality remained highly significant in multivariate models which included smoking as well as markers of severity and disease activity such as rheumatoid factor, nodular disease, and C-reactive protein (CRP). CONCLUSIONS: The serum level of MMP-8 is a strong predictor of mortality in RA, especially that due to respiratory disease. This finding is consistent with increased activation of neutrophils in RA and identifies serum MMP-8 as a useful marker for increased risk of premature death.

Clinical and echocardiographic features of children with rheumatic heart disease and their serum cytokine profile.

Acute rheumatic fever (ARF) and rheumatic heart disease (RHD) constitute important public health problems in developing countries. Children with ARF and RHD seen at Children's Hospital-Sudan from May 2008-2009 were examined clinically and by echocardiography. Blood cytokines (interleukin 10 (IL10), Tumor necrosis factor alpha (TNF- alpha) and interferon gamma (IFN-gamma) were done. Thirty six children were enrolled; 63% had established RHD, and 37% ARF. Mitral regurgitation (MR) was the most common lesion (94%).Ninety five percent of the valve lesions were severe. The serum interleukin IL10 level ranged between 3-6 pg/ml. TNF alpha levels were 9- 100 pg/ml in 12 patients (40%), 101-1000 pg/ml in 10 patients (33%), more than 1000 in 8 patients (26%). The level of IFN gamma ranged between 2-7 pg/m in all patients except 2 (84 and 135 pg/ml). RHD is manifested with severe valvular lesions and a high TNF alpha indicating and ongoing inflammation.

Autoantigens identified by screening a human heart cDNA library with acute rheumatic fever sera.

Acute rheumatic fever (ARF) is an autoimmune sequela of group A streptococcal infection mostly affecting school-aged children. Recurrent episodes of ARF can result in the development of rheumatic heart disease (RHD). One in 40 indigenous Australians in the Northern Territory is affected by RHD. This disease mostly impacts young people; 45% of those who require heart valve surgery in Australia due to RHD are younger than 25 years old. ARF is characterized by autoimmune attack of the heart; therefore, the presence of the autoantibodies involved could potentially be used to diagnose ARF. To this end, a human heart cDNA library was screened with serum from a patient with ARF, and 12 autoreactive human heart antigens were identified. They include five different IgG heavy chains and a range of tissue-specific cell-signaling proteins, species of which have been implicated in other autoimmune diseases. Preliminary ELISA results show that ARF patients have significantly higher levels of antibodies recognizing the cardiac autoantigens than controls. These antigens are promising candidates for the development of a serological assay for the diagnosis of ARF. The nature of the proteins identified has exciting implications for future research into the pathogenesis of ARF.

Efficacy of anti-CD20 treatment in patients with rheumatoid arthritis resistant to a combination of methotrexate/anti-TNF therapy.

Rheumatoid arthritis (RA) is characterized by chronic joint inflammation and destruction. B cells play important role in modulating immune responses in RA. In the present study we assessed the impact of the B cell targeting as a third line treatment option. Forty-six patients with established erosive RA non-responding to combination treatment with DMARDs and TNF-alpha inhibitors were treated with anti-CD20 antibodies (rituximab). Rituximab was given intravenously once weekly on four occasions. All patients continued with the previous DMARD. Patients were followed by DAS28, levels of circulating B cells, frequency of immunoglobulin-producing cells, immunoglobulins, and rheumatoid factor levels during the period of 12-58 months. Clinical improvement was achieved in 34 of 46 patients (73%) supported by a significant reduction in DAS28 (from 6.04 to 4.64, P < 0.001). Infusion of rituximab resulted in the elimination of circulating B cells in all but one patient. Within 12 months follow-up, B cells returned to circulation in 86% of patients. Fifty-three percent of the patients were successfully retreated with rituximab or re-started with anti-TNF-alpha treatment. Of the 11 non-responders, five were retreated with anti-CD20 within 2 months, four of them with success, four patients received TNF-alpha inhibitors, the remaining two patients received an additional DMARD. Most of the RA patients resistant to TNF-alpha inhibitors may be effectively treated with anti-CD20 antibodies. The treatment is well tolerated and may be used repeatedly in the same patient and potentially increase sensitivity to previously inefficient treatment modalities.

Adrenomedullin and total nitrite levels in children with acute rheumatic fever.

OBJECTIVE: To investigate the levels of adrenomedullin (AM) and total nitrite, a stable product of nitric oxide (NO), in children with acute rheumatic fever (ARF). DESIGN AND METHODS: Eleven children with ARF were investigated in comparison with 14 healthy controls. Adrenomedullin was detected by HPLC, while total nitrite was quantitated by the Griess reaction. RESULTS: Plasma urinary AM and total nitrite levels were significantly higher in children with ARF, irrespective of whether they were in the acute or convalescent phase of disease. Plasma AM (pmol/mL) levels were 49.19 +/- 3.23 in the acute phase, 44.52 +/- 4.26 in the convalescent phase, 35.49 +/- 3.43 in controls, and urinary AM excretion (pmol/mg creatinine) was 43.45 +/- 18.40 in the acute phase, 32.38 +/- 15.37 in the convalescent phase, and 24.84 +/- 11.38 in controls. Plasma total nitrite levels (mumol/L) were 75.37 +/- 13.13 in the acute phase, 59.81 +/- 12.78 in the convalescent phase, and 41.09 +/- 10.27 in controls. Urinary total nitrite excretion (mumol/mg creatinine) was 3.82 +/- 1.56 in the acute phase, 2.15 +/- 0.58 in the convalescent phase, and 1.33 +/- 0.61 in controls. The differences were statistically significant for all (P < 0.05). CONCLUSION: This study considered that AM and NO may have a role in the immunoinflammatory process of ARF.

Determinação de anti-estreptolisina "O" e proteína C reativa entre escolares do município de Laranjal, PR / Determination of antistreptolysin \"O\" and C-reactive protein among school children of Laranjal, PR

Para a determinação de anti-estreptolisina "O" e proteína C reativa, no município de Laranjal-PR, foram analisados soros de 411 escolares, entre 5 a 16 anos. Para anti-estreptolisina "O", 13,6 por cento tiveram títulos elevados e 5,1 por cento foram reativos para proteína C reativa. Não foram observadas diferenças em relação ao sexo e faixa etária.

[Changes of serum soluble tumor necrosis factor receptor I in patients with rheumatic fever].

OBJECTIVE: To study the changes and the effects of soluble tumor necrosis factor receptor I (sT-NFR I) in patients with rheumatic fever, and to find out the laboratorial marker of clinic activity in patients with rheumatic fever. METHODS: The serum concentrations of sTNFR I in 16 patients with ARF, 16 patients with chronic inactive rheumatic heart disease (CRHD) and 15 healthy controls were measured by methods of ELISA and the relationship between sTNFR I and ESR or CRP were studied. RESULTS: The sTNFR I serum concentrations in patients with ARF (3.92 +/- 1.28) ng.ml-1 were significantly higher than those with CRHD (1.43 +/- 0.66) ng.ml-1 and healthy controls (1.06 +/- 0.42) ng.ml-1 (all P < 0.01). The serum concentrations of sTNFR I in patients with CRHD were almost the same with those in healthy controls (P > 0.05); Their positive correlation was significantly observed between sTNFR I and CRP(P < 0.001), and wasn't observed between sTNFR I and ESR. CONCLUSION: The Patients with ARF have high serum levels of sTNFR I. It may be used as the laboratorial marker in the clinic assessment of activity in patients with rheumatic fever.

Antibodies to streptococcal surface enolase react with human alpha-enolase: implications in poststreptococcal sequelae.

The pathogenic mechanisms for developing acute rheumatic fever after group A streptococcal pharyngitis are still poorly understood. The glycolytic enzyme enolase is one of the major proteins on the surface of group A streptococci. Herein, significant cross-reactivity was shown between streptococcal enolase and human enolase. Fluorocytometric analysis revealed that antistreptococcal enolase antibodies react with the enolase expressed on the surface of hematopoietic cells. Furthermore, the enolase on the leukocyte surface was found to be up-regulated by inflammatory stimuli. Evaluation of antibody titers indicated that serum samples from patients with acute rheumatic fever have higher levels of antibodies that react with the human and bacterial enolases than do serum samples from patients with streptococcal pharyngitis or healthy control subjects. These results show that streptococcal enolase is a novel cross-reactive antigen that may play an important role in the initiation of the autoimmune diseases related to streptococcal infection.

Anticardiolipin antibodies in childhood rheumatic disorders.

Anticardiolipin antibodies (aCL) have been reported to occur in a wide variety of autoimmune and non-autoimmune disorders in adults. Our objective was to investigate the prevalence and isotype distribution of aCL and its relationship with the features of antiphospholipid syndrome (APS) in childhood rheumatic disorders. Between November 1995 and May 1996, all patients who visited our paediatric rheumatology clinic whose guardians signed a consent form participated in the study. The study population included 106 patients (36 systemic lupus erythematosus (SLE), 28 juvenile rheumatoid arthritis (JRA), 11 fibromyalgia, 7 sarcoidosis, 5 dermatomyositis, 3 rheumatic fever (RF), 3 vasculitis, 2 scleroderma, and 11 miscellaneous). aCL measurements were performed by enzyme linked immunoabsorbent assay (ELISA). All patients were carefully evaluated for symptoms and signs of APS. Eighteen of the 106 patients (17%) were tested positive for one or more of the three aCL isotypes. In SLE, aCL were found positive in 13 of 36 (37%); in JRA 2 of 28 (7%); in sarcoidosis 2 of 7; and in RF 1 of 3. aCL of IgG isotype were found positive in 16 patients (11 SLE, 2 sarcoidosis, 2 JRA, and 1 RF). This isotype was usually detected at low titers (16-24 GPL). aCL of IgM isotype were found positive in five patients (2 sarcoidosis, 2 SLE, 1 JRA), and aCL of IgA isotype were found positive in only three patients (2 SLE, 1 sarcoidosis). Clinical features of APS were rarely seen in our SLE population and were not associated with the presence of aCL. None of the patients in the other groups exhibited any clinical manifestations of APS. In conclusion, aCL were found in 37% of our childhood SLE patients as compared with only 7% in JRA. These were mostly aCL of IgG isotype of low titers and therefore were not associated with the main features of APS. Prospective studies with a larger sample size may be needed to ascertain the exact prevalence and clinical significance of aCL in childhood-onset SLE.

Immunological relationship between the class I epitope of streptococcal M protein and myosin.

The class I epitope of streptococcal M protein is an epidemiological marker for acute rheumatic fever (ARF)-associated serotypes of group A streptococci and is recognized by anti-M protein monoclonal antibody (MAb) 10B6. Using MAb 10B6, we determined the relationship between the class I epitope of M protein and the alpha-helical coiled-coil protein myosin. MAb 10B6 reacted by enzyme-linked immunosorbent assay and Western blotting with human cardiac myosin and rabbit skeletal myosin and its heavy meromyosin (HMM) subfragment. Overlapping synthetic peptides of M5 protein were used to identify the region of M5 protein recognized by MAb 10B6. Two C repeat peptides (C2A and C3) containing the amino acid sequence KGLRRDLDASREAK reacted with MAb 10B6. Partial sequence identity, RRDL, was found in the HMM fragment of myosin, which reacted with MAb 10B6. However, not all peptides of M5 protein and myosin containing the RRDL sequence reacted with MAb 10B6. ARF sera and sera from uncomplicated pharyngitis (UNC) reacted with C repeat region peptides of M protein, while acute glomerulonephritis sera were not as reactive. Affinity-purified human antibody to peptide C3 reacted with myosin. The data demonstrate that the class I epitope of M protein is immunologically cross-reactive with myosin and the HMM subfragment, and antibodies to peptide C3 and myosin were present in ARF and UNC sera.

[Method of measuring non-protein bound fucose]. / Metod opredeleniia fukozy, ne sviazannoi s belkami.

A method for measuring fucose not bound to proteins in the serum is developed. The level of this enzyme is shown to increase with age. It is increased in adult patients with myeloma, liver cirrhosis, and rheumatic fever and in children with exacerbations of chronic osteomyelitis and gastroduodenitis.