SERONEGATIVE CELIAC DISEASE IN BRAZILIAN PATIENTS: A SERIES OF CASES.

BACKGROUND: Celiac disease (CD) is an autoimmune disease characterized by immune reaction mostly to wheat gluten. The diagnosis is based on clinical, serological and histological findings in patients ingesting gluten. Cases that the clinical profile indicates CD and the autoantibodies are negative bring so a dilemma for the professional, as the risk of missed the diagnosis or a delay at the same. OBJECTIVE: To show the importance of correct diagnosis of cases with seronegative celiac disease (SNCD). METHODS: Ten cases of SNCD Brazilian patients were retrospectively studied (2013 to 2019). Data of clinical complaints, autoantibodies, IgA serum levels, histological findings and HLA-DQ2/DQ-8 were compiled. Dual-X densitometry, delay at diagnosis, previous autoimmune diseases and family history of CD were also checked. RESULTS: All SNCD patients presented clinical symptoms of CD, with confirmed diagnosis by histological findings of the duodenal mucosa and HLA-DQ2 and/or HLA-DQ8 positivity. All patients had normal IgA levels and negative autoantibodies (IgA-anti-transglutaminase and anti-endomysial). Dual-X densitometry detected osteopenia in two women and osteoporosis in two males, all with low levels of vitamin D. Delay diagnostic ranged from 1 to 19 years. Familiar occurrence of CD was reported in 40% of the cases. After one year of gluten-free diet, eight patients refer improve of symptoms, while duodenal biopsies, done in five cases, showed histological improvement. CONCLUSION: Patients who demonstrate the clinical profile of celiac disease with negative serology and normal levels of IgA, especially those who have family members with celiac disease, should be submitted to duodenal biopsies to look for histological findings.

Doença celíaca soronegativa em pacientes brasileiros: uma série de casos / Seronegative celiac disease in brazilian patients: a series of cases

ABSTRACT BACKGROUND: Celiac disease (CD) is an autoimmune disease characterized by immune reaction mostly to wheat gluten. The diagnosis is based on clinical, serological and histological findings in patients ingesting gluten. Cases that the clinical profile indicates CD and the autoantibodies are negative bring so a dilemma for the professional, as the risk of missed the diagnosis or a delay at the same. OBJECTIVE: To show the importance of correct diagnosis of cases with seronegative celiac disease (SNCD). METHODS: Ten cases of SNCD Brazilian patients were retrospectively studied (2013 to 2019). Data of clinical complaints, autoantibodies, IgA serum levels, histological findings and HLA-DQ2/DQ-8 were compiled. Dual-X densitometry, delay at diagnosis, previous autoimmune diseases and family history of CD were also checked. RESULTS: All SNCD patients presented clinical symptoms of CD, with confirmed diagnosis by histological findings of the duodenal mucosa and HLA-DQ2 and/or HLA-DQ8 positivity. All patients had normal IgA levels and negative autoantibodies (IgA-anti-transglutaminase and anti-endomysial). Dual-X densitometry detected osteopenia in two women and osteoporosis in two males, all with low levels of vitamin D. Delay diagnostic ranged from 1 to 19 years. Familiar occurrence of CD was reported in 40% of the cases. After one year of gluten-free diet, eight patients refer improve of symptoms, while duodenal biopsies, done in five cases, showed histological improvement. CONCLUSION: Patients who demonstrate the clinical profile of celiac disease with negative serology and normal levels of IgA, especially those who have family members with celiac disease, should be submitted to duodenal biopsies to look for histological findings.

RESUMO CONTEXTO: A doença celíaca (DC) é uma doença autoimune caracterizada por reação imune principalmente ao glúten do trigo. O diagnóstico é baseado em achados clínicos, sorológicos e histológicos em pacientes que ingerem glúten. Casos em que o perfil clínico indica DC e os autoanticorpos são negativos trazem um dilema para o profissional, como o risco de não realizar ou atrasar o diagnóstico da DC. OBJETIVO: Mostrar a importância do diagnóstico correto de casos com doença celíaca soronegativa (DCSN). MÉTODOS: Dez casos de pacientes brasileiros com DCSN foram estudados retrospectivamente (2013 a 2019). Foram compilados dados de queixas clínicas, autoanticorpos, níveis séricos de IgA, achados histológicos e HLA-DQ2 / DQ-8. Densitometria, atraso no diagnóstico, doenças autoimunes prévias e histórico familiar de DC também foram verificados. RESULTADOS: Todos os pacientes com DCSN apresentaram sintomas clínicos de DC, com diagnóstico confirmado por achados histológicos da mucosa duodenal e positividade para HLA-DQ2 e/ou HLA-DQ8. Todos os pacientes apresentavam níveis normais de IgA e autoanticorpos negativos (IgA-anti-transglutaminase e anti-endomisial). A densitometria detectou osteopenia em duas mulheres e osteoporose em dois homens, todos com baixos níveis de vitamina D. O atraso no diagnóstico variou de 1 a 19 anos. A ocorrência familiar de DC foi relatada em 40% dos casos. Após 1 ano de dieta isenta em glúten, oito pacientes referem melhora dos sintomas, enquanto as biópsias duodenais, realizadas em cinco casos, mostraram melhora histológica. CONCLUSÃO: Pacientes que apresentam quadro clínico de doença celíaca com sorologia negativa e níveis normais de IgA, principalmente aqueles que possuem familiares com doença celíaca, devem ser submetidos à biópsia duodenal para pesquisa de achados histológicos.

Cardiovascular risk and mannose binding lectin in patients with rheumatoid arthritis from southern Brazil.

BACKGROUND: Mannose binding lectin (MBL) appears to be involved in susceptibility to rheumatoid arthritis (RA), in the inflammatory process and in the genesis of atherosclerotic disease. OBJECTIVE: To study the association of MBL serum levels and its genotypic variation with carotid arteries intimal thickness (IMT) in RA patients from Southern Brazil. METHODS: MBL serum levels, MBL2 genotyping and IMT were investigated in 90 RA patients along with their demographic, clinical and laboratory profile. MBL levels and MBL2 genotyping were evaluated in 90 healthy controls. RESULTS: A significant lower MBL serum concentration was observed in patients with RA in relation to controls (528 ng/mL vs 937.5 ng/mL, p = 0.05, respectively). The median IMT in RA patients was 0.59 mm (0.51 to 0.85 mm). There was no correlation between levels of MBL with disease activity, erythrocyte sedimentation rate, autoantibodies presence or IMT (p = NS). A weak and negative correlation was found between MBL and CRP levels (Rho = -0.24; p = 0.02;). The MBL2 variant at codon 54 (variant B) and HYPA haplotype were the most frequently observed in the RA sample (67.5% and 31.7%). MBL2 wild type (A/A) were associated with lower IMT when compared with heterozygotes (A/O; p = 0.04) and low producers (O/O; p = 0.05). In addition, high producers genotypes had lower levels of CRP when compared with medium (p = 0.04) or with low producers (p = 0.05). CONCLUSION: RA patients had lower MBL levels than controls. MBL were negatively associated with CRP serum levels; low MBL genotypes producers increased thickness of the IMT than high producers.

Rheumatic Disease Autoantibodies in Patients with Autoimmune Thyroid Diseases.

BACKGROUND: Patients with autoimmune thyroid diseases (ATD) such as Graves' disease (GD) and Hashimoto thyroiditis (HT) may have non-organ specific autoantibodies such as antinuclear antibodies (ANA) and rheumatoid factor (RF). AIM: To study the prevalence of rheumatic autoantibodies in a group of ATD patients without known rheumatic diseases and to evaluate its association with the patients' epidemiological and treatment profiles. To follow positive non-organ specific autoantibody-positive ATD individuals to investigate whether they will develop a rheumatic disorder. METHODS: A sample of 154 ATD patients (70 HT and 84 GD; mean age 45.3 ± 14.2) had determination of ANA by immunofluorescence, using hep-2 cells as substrate, extractable nuclear antigen profile by ELISA kits and RF by latex agglutination. Epidemiological and treatment profiles were obtained through chart review. These patients were followed for the mean period of 5 years, between 2010 and 2015. RESULTS: Positive ANA was found in 17.5% (27/154) of the patients: anti-Ro/SS-A in 4/154 (2.5%); anti-RNP in 4/154 (2.5%), and anti-La/SS-B in 3/154 (1.9%). None had anti-Sm antibodies. RF was detected in 12/154 (7.7%) of ATD patients and was more common in older individuals (p = 0.007). There was a positive association between the presence of RF and ANA (p = 0.03; OR 3.89; 95% CI 1.1-13.3). None of the patients with positive autoantibodies developed clinical rheumatic diseases during the period of observation. CONCLUSION: We found rheumatic autoantibodies in 17.5% of ATD patients without rheumatic diseases. None of them were associated with the appearance of clinical rheumatic disorder during the period of 5 years.

Anticoagulant Choices Affect the Mean Platelet Volume Measurement by Impedance.

BACKGROUND: Mean platelet volume (MPV) is a parameter that evaluates the platelet size. Clinical applications of MPV are limited because of its poor standardization in routine laboratories. This study analyzed the effect of anticoagulants on MPV measurements by impedance technology. METHODS: Blood from 36 healthy volunteers was collected in vacuum tubes filled with K2EDTA and sodium citrate, analyzed immediately (basal) and at 1, 2, and 3 hours after venipuncture. RESULTS: Comparisons between the anticoagulants demonstrated a significant difference (p < 0.05) after 1 hour of exposure with K2EDTA, causing a time-dependent increase on MPV measured. No significant changes in MPV were observed with sodium citrate with 3 hours of exposure (p > 0.05). CONCLUSIONS: The use of sodium citrate is highly indicated for assessment of MPV when the measurement time after blood collection is estimated to be more than 1 hour.

Mannose-binding lectin deficiency and miscarriages in rheumatoid arthritis.

OBJECTIVE: To investigate the association between mannose-binding lectin (MBL) serum level and MBL2 polymorphisms, and the frequency of spontaneous miscarriages in rheumatoid arthritis (RA) patients. METHODS: One hundred seventy seven women (mean age 50 years) with RA from Southern Brazil were studied and 4.5% had a history of abortion (8/177). The MBL levels were determined by ELISA. MBL2 polymorphisms in the promoter (-550H/L, -221X/Y), 5' untranslated region (4 P/Q) and exon 1 (p.Gly54Asp: B allele, p.Arg52Cys: D allele and p.Gly57Glu: C allele; collectively labelled O) were genotyped by sequencing. RESULTS: Mannose-binding lectin levels of RA patients ranged from ≤100 ng/mL to 6640 ng/mL (median 541.5 ng/mL). There was a significant difference in MBL median levels (100 ng/mL vs. 625 ng/mL, respectively, p = .001) and frequency of MBL deficiency (75.0% vs. 24.1%, p = .007, OR = 10.3, 95%CI = 1.9-55.4), in patients with a history of miscarriage vs those without it. Patients with RA and miscarriage had more frequently haplotypes related with low MBL levels (p = .007, OR = 10.5, 95%CI = 1.3-84) than high producers. Moreover, LYPB haplotype and O allele were significantly associated with the occurrence of miscarriage (p = .001, OR = 9.7, 95%CI = 2.4-39.1 and p = .009, OR = 5.9, 95%CI = 1.4-23.4, respectively). CONCLUSIONS: The results suggest that MBL deficiency and the presence of MBL2 gene polymorphisms that lead to MBL deficiency are risk factors for the occurrence of miscarriage in patients with RA.

Analysis of four serum biomarkers in rheumatoid arthritis: association with extra articular manifestations in patients and arthralgia in relatives / Análise de quatro marcadores sorológicos na artrite reumatoide: associação com manifestações extra-articulares no paciente e artralgia em familiares

ABSTRACT Objectives: To evaluate the frequency of four serum biomarkers in RA patients and their relatives and identify possible associations with clinical findings of the disease. Methods: This was a transversal analytical study. Anti-cyclic citrullinated peptide (anti-CCP), anti-mutated citrullinated vimentin (anti-MCV) and IgA-rheumatoid factor (RF) were determined by ELISA and IgM-RF by latex agglutination in 210 RA patients, 198 relatives and 92 healthy controls from Southern Brazil. Clinical and demographic data were obtained through charts review and questionnaires. Results: A higher positivity for all antibodies was observed in RA patients when compared to relatives and controls (p < 0.0001). IgA-RF was more frequent in relatives compared to controls (14.6% vs. 5.4%, p = 0.03, OR = 2.98; 95% CI = 1.11-7.98) whereas anti-CCP was the most common biomarker among RA patients (75.6%). Concomitant positivity for the four biomarkers was more common in patients (46.2%, p < 0.0001). Relatives and controls were mostly positive for just one biomarker (20.2%, p < 0.0001 and 15.2%, p = 0.016, respectively). No association was observed between the number of positive biomarkers and age of disease onset, functional class or tobacco exposure. In seronegative patients predominate absence of extra articular manifestations (EAMs) (p = 0.01; OR = 3.25; 95% CI = 1.16-10.66). Arthralgia was present in positive relatives, regardless the type of biomarker. Conclusions: A higher number of biomarkers was present in RA patients with EAMs. Positivity of biomarkers was related to arthralgia in relatives. These findings reinforce the link between distinct biomarkers and the pathophysiologic mechanisms of AR.

RESUMO Objetivos: Avaliar a frequência de quatro marcadores sorológicos em pacientes com AR e seus familiares e identificar possíveis associações com achados clínicos da doença. Métodos: Estudo analítico transversal. Determinaram-se os níveis de anticorpos antipeptídeo citrulinado cíclico (anti-CCP), anticorpos antivimentina citrulinada-mutada (anti-MCV) e fator reumatoide (FR) IgA por Elisa e de FR-IgM por aglutinação em látex em 210 pacientes com AR, 198 familiares e 92 controles saudáveis do sul do Brasil. Coletaram-se dados clínicos e demográficos por meio da revisão de prontuários e questionários. Resultados: Observou-se maior positividade para todos os anticorpos em pacientes com AR em comparação com os familiares e controles (p < 0,0001). O FR-IgA era mais frequente em familiares quando comparados com os controles (14,6% versus 5,4%, p = 0,03, OR = 2,98; IC95% = 1,11 a 7,98). O anti-CCP foi o biomarcador mais comum entre pacientes com AR (75,6%). A positividade concomitante para os quatro biomarcadores foi mais comum nos pacientes (46,2%, p < 0,0001). Familiares e controles eram positivos em sua maioria para apenas um biomarcador (20,2%, p < 0,0001 e 15,2%, p = 0,016, respectivamente). Não foi observada associação entre o número de biomarcadores positivos e a idade de início da doença, classe funcional ou exposição ao fumo. Em pacientes soronegativos, predominou a ausência de manifestações extra-articulares (MEA) (p = 0,01; OR = 3,25; IC95% = 1,16 a 10,66). A artralgia estava presente em familiares positivos, independentemente do tipo de biomarcador. Conclusões: Um maior número de biomarcadores estava presente em pacientes com AR com MEA. A positividade dos biomarcadores estava relacionada com a artralgia em familiares. Esses achados reforçam a ligação entre os diferentes biomarcadores e os mecanismos fisiopatológicos da AR.

Analysis of four serum biomarkers in rheumatoid arthritis: association with extra articular manifestations in patients and arthralgia in relatives.

OBJECTIVES: To evaluate the frequency of four serum biomarkers in RA patients and their relatives and identify possible associations with clinical findings of the disease. METHODS: This was a transversal analytical study. Anti-cyclic citrullinated peptide (anti-CCP), anti-mutated citrullinated vimentin (anti-MCV) and IgA-rheumatoid factor (RF) were determined by ELISA and IgM-RF by latex agglutination in 210 RA patients, 198 relatives and 92 healthy controls from Southern Brazil. Clinical and demographic data were obtained through charts review and questionnaires. RESULTS: A higher positivity for all antibodies was observed in RA patients when compared to relatives and controls (p<0.0001). IgA-RF was more frequent in relatives compared to controls (14.6% vs. 5.4%, p=0.03, OR=2.98; 95% CI=1.11-7.98) whereas anti-CCP was the most common biomarker among RA patients (75.6%). Concomitant positivity for the four biomarkers was more common in patients (46.2%, p<0.0001). Relatives and controls were mostly positive for just one biomarker (20.2%, p<0.0001 and 15.2%, p=0.016, respectively). No association was observed between the number of positive biomarkers and age of disease onset, functional class or tobacco exposure. In seronegative patients predominate absence of extra articular manifestations (EAMs) (p=0.01; OR=3.25; 95% CI=1.16-10.66). Arthralgia was present in positive relatives, regardless the type of biomarker. CONCLUSIONS: A higher number of biomarkers was present in RA patients with EAMs. Positivity of biomarkers was related to arthralgia in relatives. These findings reinforce the link between distinct biomarkers and the pathophysiologic mechanisms of AR.

Mannose-Binding Lectin Deficiency in Brazilian Patients with Spondyloarthritis.

BACKGROUND: Infections are usually involved in the pathogenesis of spondyloarthritis (SpA). Mannose-binding lectin (MBL) is a component of the innate immune system with an important role in microbial defense. OBJECTIVE: To study the prevalence of MBL deficiency in SpA patients as well as its influence in the clinical profile of these diseases. METHODS: We studied 89 SpA patients and 89 healthy individuals, paired for age and gender. MBL serum levels were measured by ELISA test. Individuals with levels ≤100 ng/mL were considered deficient. SpA patients had determination of Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Ankylosing Spondylitis Disease Activity Score (ASDAS)-CRP, Bath Ankylosing Spondylitis Functional Index (BASFI), C reactive protein (CRP), erythrocyte sedimentation rate (ESR), and review of their clinical profile. RESULTS: SpA patients had MBL levels ranging from 100 to 4100 ng/mL (median = 375 ng/mL); controls levels ranged from 100 to 4703 ng/mL (median = 1204 ng/mL; p < 0.0001). The prevalence of MBL deficiency was 27/89 (30.3%) in SpA patients and 12/89 (13.5%) in controls, with p = 0.01; OR = 2.5 (95% IC = 1.2-5.3). No association/correlation was found between MBL levels with BASDAI, BASFI, age at disease onset, ASDAS-CRP, ESR, CRP, presence of uveitis, HLAB27, peripheral arthritis, or SpA subtype (all p = NS). CONCLUSION: MBL levels may be linked with the occurrence of SpA but do not influence its phenotype.

Rheumatic Disease Autoantibodies in Autoimmune Liver Diseases.

BACKGROUND: Autoimmune liver diseases (ALDs) are known to be associated with systemic autoimmune rheumatic diseases (SARDs) and their autoantibodies. We aimed to study the prevalence of SARDs and related autoantibodies, as well as their prognostic implications in a group of patients with ALDs. METHODS: This was a cross-sectional study. Sixty patients with ALDs (38.3% with autoimmune hepatitis; 11.7% with primary biliary cirrhosis; 25% with primary sclerosing cholangitis and 25% with overlap syndrome) were studied for the presence of SARDs and their autoantibodies. RESULTS: There was autoimmune rheumatic disease in 20% of the studied sample. Systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA) were the commonest (11.6% and 5%, respectively). Antinuclear antibodies (ANAs) were present in 35% of the patients, followed by anti-Ro (20.0%); anti-nucleosome (18.3%); rheumatoid factor (10%) anti-CCP (8.3%); anti-RNP (8.3%); anti-ds-DNA (6.6%); anti-La (3.3%); anti-Sm (3.3%), anti-ribosomal P (3.3%). Anti-Ro (p = 0.0004), anti-La (p = 0.03), anti-RNP (p = 0.04) and anti-Sm (p = 0.03) were commonly found in patients with SARD, but not anti-DNA, anti-nucleosome and anti-ribosomal P. No differences were found in liver function tests regarding to the presence of autoantibodies. CONCLUSIONS: There was a high prevalence of SARD and their autoantibodies in ALD patients. Anti-Ro, anti-La, anti-RNP and anti-Sm positivity points to an association with systemic autoimmune rheumatic diseases. The presence of autoantibodies was not related to liver function tests.

Anti-alpha-fodrin antibodies in patients with Sjögren's syndrome secondary to rheumatoid arthritis / Anticorpos antialfafodrina em pacientes com síndrome de Sjögren secundária a artrite reumatoide

ABSTRACT Introduction: The Sjögren's syndrome (SS) is an autoimmune disease characterized by lymphocytic infiltration. The currently most researched antibodies for its diagnosis are anti-La and anti-Ro, which, however, have low specificity in the case of SS secondary to rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). The antibodies against alpha-fodrin (AF) have been proposed to diagnose SS. Objective: In the present study, we investigated the anti-AF antibody in a group of RA patients with and without secondary SS (sSS). Methods: Were studied 90 consecutive patients with RA (48.8% of them with SS), and samples of 45 healthy volunteers. Anti-AF immunoglobulin class G (IgG) and anti-AF immunoglobulin class A (IgA) were investigated by enzyme-linked immunosorbent assay (ELISA) and were considered positive when >15 U/ml. Demographic, clinical, and serological data were obtained from chart reviews. Results: Anti-AF IgA was positive in 46/90 (51.1%) of the RA sample and 3/45 (6.7%) of controls (p < 0.001); anti-AF IgG was found in 21/90 (23.3%) of RA patients and none of controls (p = 0.037). Neither IgA nor IgG anti-AF antibodies showed significant difference in patients with and without sSS. Conclusion: In our study, anti-AF IgA and anti-AF IgG neither alloweded diagnosis of sSS in RA patients, nor marked any special clinical or serological finding.

RESUMO Introdução: A síndrome de Sjögren (SS) é uma doença autoimune caracterizada por infiltração linfocítica. Atualmente os anticorpos mais pesquisados para seu diagnóstico são anti-Ro e anti-La, que, no entanto, apresentam baixa especificidade nos casos de SS secundária a artrite reumatoide (AR) e lúpus eritematoso sistêmico (LES). Os anticorpos contra alfafodrina (AF) foram propostos para diagnosticar SS. Objetivo: Investigamos o anticorpo anti- AF em um grupo de portadores de AR com e sem SS secundária (SSs). Material e métodos: Foram estudados 90 pacientes consecutivos com AR (48,8% com SS) e amostras de 45 voluntários saudáveis. Imunoglobulina da classe G (IgG) e imunoglobulina da classe A (IgA) anti-AF foram investigadas por ensaio imunossorvente ligado à enzima (ELISA), sendo consideradas positivas quando acima de 15 U/ml. Dados demográficos, clínicos e sorológicos foram obtidos a partir de revisão de prontuários. Resultados: IgA anti-AF foi positiva em 46/90 (51,1%) das amostras com AR e 3/45 (6,7%) das amostrascontrole (p < 0,001); IgG anti-AF foi encontrada em 21/90 (23,3%) de pacientes com AR e nenhum dos controles (p = 0,037). Nem IgA anti-AF nem IgG anti-AF conseguiram diferenciar pacientes com e sem SSs. Conclusão: IgG anti-AF e IgA anti-AF foram investigadas e não contribuíram especificamente para diferenciar pacientes com AR que sofrem ou não de SS, além de não conseguirem estabelecer o diagnóstico de SS em pacientes com AR.

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-cyclic citrullinated peptide antibodies in adult patients with juvenile idiopathic arthritis.

BACKGROUND: Antibodies to cyclic citrullinated peptide (anti-CCP) have been found in different proportions in the juvenile idiopathic arthritis (JIA) population. The majority of studies have been done in children or mixed population (children plus adults). AIM: The objective of the study was to study the prevalence of anti-CCP in JIA adult patients. METHODS: Anti-CCP3 was searched for in 49 adult patients with JIA and associated with clinical and demographics data. As comparisons, 156 patients with adult rheumatoid arthritis (RA) and 100 healthy volunteers were studied. RESULTS: Nine patients (18.3%) were positive for anti-CCP3. All of them had the polyarthritis form. This antibody was more common in JIA than in control subjects (P = 0.0002) and less common in JIA than in adult RA patients (P < 0.0001), but the rheumatoid factor polyarticular form of JIA had the same prevalence as in adult RA patients (P = 0.33).In JIA patients, anti-CCP had a positive association with the presence of rheumatoid factor (P < 0.0001), worse functional status (P = 0.04), need for orthopedic surgery (P = 0.01), and later disease onset (P = 0.0007). CONCLUSIONS: In adult patients with JIA, the prevalence of anti-CCP3 is 18%, and its presence may define a sample of patients with worse prognosis.

Liver autoantibodies in patients with scleroderma.

Association between autoimmune liver diseases and scleroderma has been described. The purpose of this study was to study the prevalence of antimithocondrial antibody (AMA), antismooth muscle antibodies (SMA), and liver-kidney-microsomal (LKM-1) autoantibody in a cohort of 63 scleroderma patients and 100 healthy controls. The autoantibodies AMA, SMA, and LKM were determined by indirect immunofluorescence. Patients' charts were reviewed for demographic data, scleroderma form, and clinical and anti-nuclear antibody profile, aiming a comparison between patients with and without liver autoantibodies. Nine patients (14.3%) were positive for at least one of the liver autoantibodies; only one patient had both AMA and SMA positive. Antibody SMA was positive in 6.4% (4/63) patients; AMA was present in 9.52% (6/63) of them; none were positive to LKM-1. In the control group just one patient (1%) was SMA positive; the other autoantibodies were negative. There is an increased prevalence of liver autoantibodies in patients with scleroderma than in control population. These patients should be carefully followed for liver dysfunction.

Mannan-binding lectin deficiency increases the risk of recurrent infections in children with Down's syndrome.

Down syndrome (DS) is the most frequent cause of intellectual disability worldwide. DS individuals present abnormalities in the immune system that include high susceptibility to recurrent infections (RI) as well as to autoimmune diseases. Respiratory tract infections remain one of the major causes of death in DS individuals. Mannan-binding lectin (MBL) functions as an opsonina and initiates the lectin complement pathway. MBL deficiency was shown to increase the susceptibility to different infectious diseases, notably by extracellular pathogens. In the present study, MBL circulating levels were evaluated in 150 children with DS from Brazil, to clarify whether MBL deficiency is associated with the presence of RI in these patients. According to the clinical history 30.7% (46/150) of the DS children experienced RI, and MBL deficiency was seen in 34.8% (16/46) of them compared with 13.5% (14/104) of the DS children without RI (p = 0.005, odds ratio = 3.43, 95% confidence interval = 1.5-7.85). Moreover, MBL deficiency was significantly associated with the occurrence of pneumonia when compared with DS without RI (37.5%, 12/32 vs. 13.5% 14/104, p = 0.005, odds ratio = 3.68, 95% confidence interval = 1.5-6.95). These findings demonstrated that MBL deficiency increases the susceptibility to RI in DS patients and that, in the future, they could potentially benefit from MBL therapy.

Lectina ligante de manose (MBL): características biológicas e associação com doenças / Mannan-binding lectin (MBL): biological characteristics and diseases association

Objetivo: Fazer levantamento de dados recentes relacionados a aspectos estruturais e biológicos da lectina ligante de manose (MBL), assim como da sua participação na fisiopatogenia de diversas doenças. Fonte de dados: Informações contidas em livros, assim como em periódicos acessados principalmente através do Portal da Capes e Pubmed. Síntese dos dados: A MBL é uma proteína com importante participação no sistema imunológico inato e representa a proteína central da ativação da via das lectinas do complemento. A concentração plasmática da MBL é determinada genetica¬mente e varia significativamente entre os indivíduos. A MBL reconhece unidades de açúcares como N-acetil-glucosamina, manose, N-acetil-manosamina, fucose e glucose na superfície de microorganismos, possibilitando a interação com vírus, bactérias, leveduras, fungos e protozoários, levando à sua opsoni¬zação e fagocitose. Dados recentes mostram que a MBL participa na modulação da inflamação e apoptose ao ligar-se a recep¬tores na superfície de fagócitos. A MBL apresenta papel complexo nas doenças. Sua deficiência tem sido associada a maior susceptibilidade a doenças infecciosas, especialmente por patógenos extracelulares. Por outro lado, altas concentrações de MBL sérica têm sido associadas a infecções por microorganismos intracelulares como Leishmania spp. e M. leprae. Há evidências que a MBL também tem participação em condições co¬mo abortos espontâneos, doenças autoimunes e inflamatórias. A MBL é considerada uma proteína de fase aguda, embora apresente aumentos sé ricos modestos quando comparada à proteína C reativa (PCR). Conclusões: Estudos evidenciam ao longo dos anos a notável influência da MBL na resposta inata do hospedeiro e sua participação nos diferentes processos inflamatórios e infecciosos, respaldados na perspectiva que representa a terapia de reposição dessa proteína.