Introdução: O Lúpus eritematoso sistêmico (LES) é uma doença inflamatória autoimune crônica de etiologia ainda pouco conhecida, e de natureza pleomórfica, que intercala períodos de atividade e remissão. O desenvolvimento da autoimunidade no LES está associado à perda da tolerância imunológica e do controle imunorregulatório, tendo seus achados clínicos e laboratoriais variados. A atividade do LES pode ser medida pelo SLEDAI (systemic lupus erythematosus disease activity index) que é uma ferramenta complexa e que exige treinamento e conhecimento para sua aplicação. O volume plaquetário médio (VPM) é um marcador de ativação de plaquetas associado à inflamação, o que o torna um potencial candidato para a avaliação de atividade de doença no LES. Objetivos: Avaliar o VPM em pacientes com LES e comparar com indivíduos hígidos. Estudar a correlação entre o VPM e o índice de atividade de doença (SLEDAI) nos pacientes com LES. Analisar a correlação entre o VPM e a velocidade de sedimentação globular (VSG), a proteína C reativa (PCR), e os componentes do complemento C3 e C4 Métodos: Estudo transversal no qual foram incluídos 81 pacientes com LES segundo critérios de classificação diagnóstica do American College of Rheumatology (ACR), e 58 controles hígidos. Os pacientes foram selecionados consecutivamente por conveniência, de acordo com exames laboratoriais e SLEDAI devidamente calculados. As coletas foram realizadas entre outubro de 2015 e julho de 2016. LES ativo foi definido como SLEDAI>0 no momento da coleta. O VPM foi analisado no equipamento de automação Sysmex XE 5000. Resultados: O VPM estava reduzido nos pacientes com LES em atividade, quando comparado ao grupo de pacientes com LES inativo (10,0±0,7fL vs. 10,7±1,0fL, p=0,005). Existe uma fraca correlação inversa entre o valor do SLEDAI e o VPM (r=-0,29, p=0,009). Houve uma diferença significativa no VPM entre o grupo dos controles e os pacientes com LES ativo / Background Systemic Lupus Erythematosus (SLE) is an inflammatory autoimmune chronic disease etiology still unknown, and pleomorphic nature, which intersperses periods of activity and remission. The development of autoimmunity in SLE is related to loss of immunological tolerance and immunoregulatory control and clinical symptoms can be varied. The SLE activity can be measured by SLEDAI (systemic lupus erythematosus disease activity) which is a complex tool and it requires time and knowledge for your application. The MPV (mean platelet volume) is a marker of platelet activation and has been shown to be associated with inflammation, which makes it a potential candidate for use in the assessment of disease activity in SLE. In this study, we evaluated the MPV (Mean platelet volume) in healthy individuals and compared with SLE patients and correlate with SLEDAI VPM. Objectives: -To evaluate the MPV in SLE patients and compared with healthy individuals; to study the correlation between MPV and the SLEDAI patients with SLE and assess a possible correlation between MPV with erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), complement 3 (C3), and complement 4 (C4) Methods: This is a cross-sectional study in which 81 patients with SLE according to the American College of Rheumatology (ACR) diagnostic classification criteria and 58 healthy controls were included. Patients were selected for convenience, according to laboratory tests and SLEDAI duly calculated. The collections were carried out between October 2015 and July 2016. Active LES was defined as SLEDAI>0 at the time of collection. The VPM was analyzed in the Sysmex XE 5000 automation equipment. Results: In this study in patients with active SLE, the MPV is reduced when compared to the group of patients with inactive SLE [10.0±0.7fL vs. 10.7±1.0fL, p=0.005]. There is a weak inverse correlation between the SLEDAI value and the MPV (r=-0.29, p=0.009). There was a significant difference between the control group and the patients with active SLE (10.9 ±1.0fL vs. 10.0±0.7fL, p <0.001). In contrast, the MPV was similar between the control group and the group of patients with inactive SLE (10.9±1.0fLvs10.7±1.0fL, p=0.40). There was no correlation between MVP and CRP, ESR, C3 and C4. Conclusion: MPV is decreased in patients with active SLE and inversely correlated with SLEDAI. Despite the difference between MVP values, between active and inactive SLE patients, the results may not be clinically relevant. Prospective longitudinal studies are needed to better characterize the fluctuation of MPV in different states of disease activity to more clearly define the role of MPV in SLE.

Introdução: O Lúpus eritematoso sistêmico (LES) é uma doença inflamatória autoimune crônica de etiologia ainda pouco conhecida, e de natureza pleomórfica, que intercala períodos de atividade e remissão. O desenvolvimento da autoimunidade no LES está associado à perda da tolerância imunológica e do controle imunorregulatório, tendo seus achados clínicos e laboratoriais variados. A atividade do LES pode ser medida pelo SLEDAI (systemic lupus erythematosus disease activity index) que é uma ferramenta complexa e que exige treinamento e conhecimento para sua aplicação. O volume plaquetário médio (VPM) é um marcador de ativação de plaquetas associado à inflamação, o que o torna um potencial candidato para a avaliação de atividade de doença no LES. Objetivos: Avaliar o VPM em pacientes com LES e comparar com indivíduos hígidos. Estudar a correlação entre o VPM e o índice de atividade de doença (SLEDAI) nos pacientes com LES. Analisar a correlação entre o VPM e a velocidade de sedimentação globular (VSG), a proteína C reativa (PCR), e os componentes do complemento C3 e C4 Métodos: Estudo transversal no qual foram incluídos 81 pacientes com LES segundo critérios de classificação diagnóstica do American College of Rheumatology (ACR), e 58 controles hígidos. Os pacientes foram selecionados consecutivamente por conveniência, de acordo com exames laboratoriais e SLEDAI devidamente calculados. As coletas foram realizadas entre outubro de 2015 e julho de 2016. LES ativo foi definido como SLEDAI>0 no momento da coleta. O VPM foi analisado no equipamento de automação Sysmex XE 5000. Resultados: O VPM estava reduzido nos pacientes com LES em atividade, quando comparado ao grupo de pacientes com LES inativo (10,0±0,7fL vs. 10,7±1,0fL, p=0,005). Existe uma fraca correlação inversa entre o valor do SLEDAI e o VPM (r=-0,29, p=0,009). Houve uma diferença significativa no VPM entre o grupo dos controles e os pacientes com LES ativo / Background Systemic Lupus Erythematosus (SLE) is an inflammatory autoimmune chronic disease etiology still unknown, and pleomorphic nature, which intersperses periods of activity and remission. The development of autoimmunity in SLE is related to loss of immunological tolerance and immunoregulatory control and clinical symptoms can be varied. The SLE activity can be measured by SLEDAI (systemic lupus erythematosus disease activity) which is a complex tool and it requires time and knowledge for your application. The MPV (mean platelet volume) is a marker of platelet activation and has been shown to be associated with inflammation, which makes it a potential candidate for use in the assessment of disease activity in SLE. In this study, we evaluated the MPV (Mean platelet volume) in healthy individuals and compared with SLE patients and correlate with SLEDAI VPM. Objectives: -To evaluate the MPV in SLE patients and compared with healthy individuals; to study the correlation between MPV and the SLEDAI patients with SLE and assess a possible correlation between MPV with erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), complement 3 (C3), and complement 4 (C4) Methods: This is a cross-sectional study in which 81 patients with SLE according to the American College of Rheumatology (ACR) diagnostic classification criteria and 58 healthy controls were included. Patients were selected for convenience, according to laboratory tests and SLEDAI duly calculated. The collections were carried out between October 2015 and July 2016. Active LES was defined as SLEDAI>0 at the time of collection. The VPM was analyzed in the Sysmex XE 5000 automation equipment. Results: In this study in patients with active SLE, the MPV is reduced when compared to the group of patients with inactive SLE [10.0±0.7fL vs. 10.7±1.0fL, p=0.005]. There is a weak inverse correlation between the SLEDAI value and the MPV (r=-0.29, p=0.009). There was a significant difference between the control group and the patients with active SLE (10.9 ±1.0fL vs. 10.0±0.7fL, p <0.001). In contrast, the MPV was similar between the control group and the group of patients with inactive SLE (10.9±1.0fLvs10.7±1.0fL, p=0.40). There was no correlation between MVP and CRP, ESR, C3 and C4. Conclusion: MPV is decreased in patients with active SLE and inversely correlated with SLEDAI. Despite the difference between MVP values, between active and inactive SLE patients, the results may not be clinically relevant. Prospective longitudinal studies are needed to better characterize the fluctuation of MPV in different states of disease activity to more clearly define the role of MPV in SLE.

Introdução: O Lúpus eritematoso sistêmico (LES) é uma doença inflamatória autoimune crônica de etiologia ainda pouco conhecida, e de natureza pleomórfica, que intercala períodos de atividade e remissão. O desenvolvimento da autoimunidade no LES está associado à perda da tolerância imunológica e do controle imunorregulatório, tendo seus achados clínicos e laboratoriais variados. A atividade do LES pode ser medida pelo SLEDAI (systemic lupus erythematosus disease activity index) que é uma ferramenta complexa e que exige treinamento e conhecimento para sua aplicação. O volume plaquetário médio (VPM) é um marcador de ativação de plaquetas associado à inflamação, o que o torna um potencial candidato para a avaliação de atividade de doença no LES. Objetivos: Avaliar o VPM em pacientes com LES e comparar com indivíduos hígidos. Estudar a correlação entre o VPM e o índice de atividade de doença (SLEDAI) nos pacientes com LES. Analisar a correlação entre o VPM e a velocidade de sedimentação globular (VSG), a proteína C reativa (PCR), e os componentes do complemento C3 e C4 Métodos: Estudo transversal no qual foram incluídos 81 pacientes com LES segundo critérios de classificação diagnóstica do American College of Rheumatology (ACR), e 58 controles hígidos. Os pacientes foram selecionados consecutivamente por conveniência, de acordo com exames laboratoriais e SLEDAI devidamente calculados. As coletas foram realizadas entre outubro de 2015 e julho de 2016. LES ativo foi definido como SLEDAI>0 no momento da coleta. O VPM foi analisado no equipamento de automação Sysmex XE 5000. Resultados: O VPM estava reduzido nos pacientes com LES em atividade, quando comparado ao grupo de pacientes com LES inativo (10,0±0,7fL vs. 10,7±1,0fL, p=0,005). Existe uma fraca correlação inversa entre o valor do SLEDAI e o VPM (r=-0,29, p=0,009). Houve uma diferença significativa no VPM entre o grupo dos controles e os pacientes com LES ativo / Background Systemic Lupus Erythematosus (SLE) is an inflammatory autoimmune chronic disease etiology still unknown, and pleomorphic nature, which intersperses periods of activity and remission. The development of autoimmunity in SLE is related to loss of immunological tolerance and immunoregulatory control and clinical symptoms can be varied. The SLE activity can be measured by SLEDAI (systemic lupus erythematosus disease activity) which is a complex tool and it requires time and knowledge for your application. The MPV (mean platelet volume) is a marker of platelet activation and has been shown to be associated with inflammation, which makes it a potential candidate for use in the assessment of disease activity in SLE. In this study, we evaluated the MPV (Mean platelet volume) in healthy individuals and compared with SLE patients and correlate with SLEDAI VPM. Objectives: -To evaluate the MPV in SLE patients and compared with healthy individuals; to study the correlation between MPV and the SLEDAI patients with SLE and assess a possible correlation between MPV with erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), complement 3 (C3), and complement 4 (C4) Methods: This is a cross-sectional study in which 81 patients with SLE according to the American College of Rheumatology (ACR) diagnostic classification criteria and 58 healthy controls were included. Patients were selected for convenience, according to laboratory tests and SLEDAI duly calculated. The collections were carried out between October 2015 and July 2016. Active LES was defined as SLEDAI>0 at the time of collection. The VPM was analyzed in the Sysmex XE 5000 automation equipment. Results: In this study in patients with active SLE, the MPV is reduced when compared to the group of patients with inactive SLE [10.0±0.7fL vs. 10.7±1.0fL, p=0.005]. There is a weak inverse correlation between the SLEDAI value and the MPV (r=-0.29, p=0.009). There was a significant difference between the control group and the patients with active SLE (10.9 ±1.0fL vs. 10.0±0.7fL, p <0.001). In contrast, the MPV was similar between the control group and the group of patients with inactive SLE (10.9±1.0fLvs10.7±1.0fL, p=0.40). There was no correlation between MVP and CRP, ESR, C3 and C4. Conclusion: MPV is decreased in patients with active SLE and inversely correlated with SLEDAI. Despite the difference between MVP values, between active and inactive SLE patients, the results may not be clinically relevant. Prospective longitudinal studies are needed to better characterize the fluctuation of MPV in different states of disease activity to more clearly define the role of MPV in SLE.

published_or_final_version / Social Work / Master / Master of Social Work

published_or_final_version / Medicine / Doctoral / Doctor of Philosophy

Objective: to assess the prevalence of rheumatoid arthritis (RA), systemic lupus erythematosus (SLE) and spondyloarthropathy (SpA) in Vilnius, Lithuania. Methods: 3 prevalence studies were conducted: 1. Registry-based study of the prevalence of RA and SLE; 2. Population-based study of the prevalence of RA and SLE (interview conducted by mail); 3. Poulation-based study of the prevalence of RA and SpA (interview conducted by telephone). Results: according to the Vilnius RA and SLE registry, the prevalence of RA in Vilnius at the end of year 2004 was 0,14% (95% CI 0,13-0,15), and the prevalence of SLE was 0,0174% or 17,4/100 000 (95% CI 0,0137-0,0218). The population-based study, conducted by mail, revealed 15 RA and 2 SLE cases, accounting for a prevalence rate of RA of 0,37% (95% CI 0,21-0,62), and a prevalence of SLE rate of 0,0498% (95% CI 0,006-0,180). The standardized prevalence rate according to age and sex in the Vilnius population showed an RA prevalence of 0,32% (95% CI 0,18-0,57). The population-based study, conducted be telephone, detected 16 RA and 13 SpA cases, resulting in a crude prevalence of 0,76% (95% CI 0,44-1,24) for RA and 0,62% (95% CI 0,33-1,06) for SpA. The standardized prevalence rate according to age and sex in the Vilnius population showed an RA prevalence of 0,51% (95% CI 0,29-0,96) and a SpA prevalence of – 0,75% (95% CI 0,38-1,40). / Darbo tikslas: nustatyti reumatoidinio artrito (RA), seronegatyvių spondiloartropatijų (SpA) bei sisteminės raudonosios vilkligės (SRV) paplitimą Vilniaus mieste. Darbo metodika: Buvo atlikti 3 tyrimai: 1. RA ir SRV paplitimo Vilniaus mieste apskaičiavimas, remiantis Vilniaus miesto RA ir SRV sergančių asmenų duomenų baze; 2. RA ir SRV paplitimo Vilniaus mieste populiacinis tyrimas, apklausiant Vilniaus miesto gyventojus paštu; 3. RA ir SpA paplitimo Vilniaus mieste populiacinis tyrimas, apklausiant Vilniaus miesto gyventojus telefonu. Rezultatai: remiantis Vilniaus miesto RA ir SRV sergančiųjų duomenų baze, RA paplitimas Vilniaus mieste 2004m. pabaigoje buvo 0,14% (95% PI 0,13-0,15). Apskaičiuotas SRV paplitimas Vilniuje 2004m. pabaigoje buvo 0,0174% arba 17,4/100 000 gyventojų (95% PI 0,0137-0,0218). Atlikus RA ir SRV paplitimo tyrimą (apklausą paštu), nustatyta, kad RA paplitimas Vilniuje yra 0,37% (95% PI 0,21-0,62), o SRV paplitimas – 0,0498% (95% PI 0,006-0,180). RA paplitimas buvo standartizuotas pagal amžių ir lytį, remiantis 2004m. pradžios Vilniaus miesto populiacija, apskaičiuotas standartizuotas RA paplitimas yra 0,32% (95% PI 0,18-0,57). Atlikus RA ir SpA paplitimo tyrimą (apklausą telefonu), apskaičiuotas RA paplitimas buvo 0,76% (95% PI 0,44-1,24), o SpA paplitimas - 0,62% (95% PI 0,33-1,06). RA ir SpA paplitimas buvo standartizuotas pagal amžių ir lytį, remiantis 2004m. pradžios Lietuvos populiacija, apskaičiuotas standartizuotas RA paplitimas yra 0,51% (95%... [toliau žr. visą tekstą]

Darbo tikslas: nustatyti reumatoidinio artrito (RA), seronegatyvių spondiloartropatijų (SpA) bei sisteminės raudonosios vilkligės (SRV) paplitimą Vilniaus mieste. Darbo metodika: Buvo atlikti 3 tyrimai: 1. RA ir SRV paplitimo Vilniaus mieste apskaičiavimas, remiantis Vilniaus miesto RA ir SRV sergančių asmenų duomenų baze; 2. RA ir SRV paplitimo Vilniaus mieste populiacinis tyrimas, apklausiant Vilniaus miesto gyventojus paštu; 3. RA ir SpA paplitimo Vilniaus mieste populiacinis tyrimas, apklausiant Vilniaus miesto gyventojus telefonu. Rezultatai: remiantis Vilniaus miesto RA ir SRV sergančiųjų duomenų baze, RA paplitimas Vilniaus mieste 2004m. pabaigoje buvo 0,14% (95% PI 0,13-0,15). Apskaičiuotas SRV paplitimas Vilniuje 2004m. pabaigoje buvo 0,0174% arba 17,4/100 000 gyventojų (95% PI 0,0137-0,0218). Atlikus RA ir SRV paplitimo tyrimą (apklausą paštu), nustatyta, kad RA paplitimas Vilniuje yra 0,37% (95% PI 0,21-0,62), o SRV paplitimas – 0,0498% (95% PI 0,006-0,180). RA paplitimas buvo standartizuotas pagal amžių ir lytį, remiantis 2004m. pradžios Vilniaus miesto populiacija, apskaičiuotas standartizuotas RA paplitimas yra 0,32% (95% PI 0,18-0,57). Atlikus RA ir SpA paplitimo tyrimą (apklausą telefonu), apskaičiuotas RA paplitimas buvo 0,76% (95% PI 0,44-1,24), o SpA paplitimas - 0,62% (95% PI 0,33-1,06). RA ir SpA paplitimas buvo standartizuotas pagal amžių ir lytį, remiantis 2004m. pradžios Lietuvos populiacija, apskaičiuotas standartizuotas RA paplitimas yra 0,51% (95%... [toliau žr. visą tekstą] / Objective: to assess the prevalence of rheumatoid arthritis (RA), systemic lupus erythematosus (SLE) and spondyloarthropathy (SpA) in Vilnius, Lithuania. Methods: 3 prevalence studies were conducted: 1. Registry-based study of the prevalence of RA and SLE; 2. Population-based study of the prevalence of RA and SLE (interview conducted by mail); 3. Poulation-based study of the prevalence of RA and SpA (interview conducted by telephone). Results: according to the Vilnius RA and SLE registry, the prevalence of RA in Vilnius at the end of year 2004 was 0,14% (95% CI 0,13-0,15), and the prevalence of SLE was 0,0174% or 17,4/100 000 (95% CI 0,0137-0,0218). The population-based study, conducted by mail, revealed 15 RA and 2 SLE cases, accounting for a prevalence rate of RA of 0,37% (95% CI 0,21-0,62), and a prevalence of SLE rate of 0,0498% (95% CI 0,006-0,180). The standardized prevalence rate according to age and sex in the Vilnius population showed an RA prevalence of 0,32% (95% CI 0,18-0,57). The population-based study, conducted be telephone, detected 16 RA and 13 SpA cases, resulting in a crude prevalence of 0,76% (95% CI 0,44-1,24) for RA and 0,62% (95% CI 0,33-1,06) for SpA. The standardized prevalence rate according to age and sex in the Vilnius population showed an RA prevalence of 0,51% (95% CI 0,29-0,96) and a SpA prevalence of – 0,75% (95% CI 0,38-1,40).

Autoimmune diseases are clinical manifestations of a loss-of-tolerance of the immune system against the body’s own substances and healthy tissues. Primary Sjögren’s syndrome (pSS) and systemic lupus erythematosus (SLE) are two chronic inflammatory autoimmune diseases characterized by autoantibody production and an activated type I interferon system. Although the precise mechanisms leading to autoimmune processes are not well defined, recent studies suggest that aberrant DNA methylation and gene expression patterns may play a central role in the pathogenesis of these disorders. The aim of this thesis was to investigate DNA methylation and gene expression in pSS and SLE on a genome-wide scale to advance our understanding of how these factors contribute to the diseases and to identify potential biomarkers and novel treatment targets. In study I, differential DNA methylation was analyzed in multiple tissues from pSS patients and healthy controls. We identified thousands of CpG sites with perturbed methylation; the most prominent finding was a profound hypomethylation at regulatory regions of type I interferon induced genes in pSS. In study II, a cases-case study comparing DNA methylation in pSS patients with high fatigue to patients with low fatigue, we found methylation patterns associated to the degree of fatigue. In study III, RNA-sequencing was applied to investigate the transcriptome of B cells in pSS in comparison to controls. Increased expression of type I and type II interferon regulated genes in pSS was observed, indicating ongoing immune activation in B cells. In study IV, the impact of DNA methylation on disease susceptibility and phenotypic variability in SLE was investigated. We identified DNA methylation patterns associated to disease susceptibility, SLE manifestations and different treatments. In addition, we mapped methylation quantitative trait loci and observed evidence for genetic regulation of DNA methylation in SLE.   In conclusion, the results presented in this thesis provide new insights into the molecular mechanisms underlying autoimmunity in pSS and SLE. The studies confirm the central role of the interferon system in pSS and SLE and further suggest novel genes and mechanisms to be involved in the pathogenesis these autoimmune diseases.

Two novel B cell populations were characterized in peripheral blood of patients with common variable immunodeficiency and healthy controls were observed using flow cytometry in the study supported by the grant IGA MZ ČR NKT11414-3. These B cell populations were defined as CD19+ CD27- CD21+ CD38low CD24+ IgM+ FO I and CD19+ CD27- CD21+ CD38low CD24++ IgM++ cells. Since none of found populations has ever been described, the aim of this thesis was to characterize these populations with focus on analysis of variable regions of the heavy chains of immunoglobulins and genes coding proteins participating in the process of VHDHJH formation (Rag 1, Rag 2, and TdT) produced by cells of these populations. Flow cytometry, single cell sorting, single-cell RT-PCR, IgVH, Rag 1, Rag 2, and TdT specific PCR amplification and cycle sequencing were employed to perform the molecular analysis in individual B lymphocytes. Both populations in two patients with common variable immunodeficiency, two healthy controls, and in two patients with autoimmune diseases - rheumatoid arthritis and systemic lupus erythematosus (as the disease control) - were examined. Finally, the statistical analysis was used to evaluate the differences in expression of variable regions of the heavy chains of immunoglobulins and in Rag1 and 2, and...

Introdução: Os anticorpos antiproteína P ribossomal (anti-P) são considerados marcadores sorológicos específicos do Lúpus Eritematoso Sistêmico (LES) e estão associados a acometimento hepático nesta doença. As semelhanças entre a hepatite autoimune (HAI) e a hepatite associada ao LES levou ao questionamento se o anticorpo anti-P também estaria presente na HAI. Objetivo: Avaliar a frequência e significância clínica do anticorpo anti-P em uma grande coorte de pacientes com HAI. Métodos: Foram analisados os soros de 96 pacientes com HAI, coletados no diagnóstico e comparados com 82 soros de indivíduos saudáveis. Todos os soros foram testados para a presença do anticorpo anti-P pelo método de ELISA, do anticorpo anti-DNA de dupla fita pelo método de imunofluorescência indireta usando Crithidia luciliae e do anticorpo anti-Sm pelo método de ELISA. Os critérios de exclusão adotados foram a presença de outros anticorpos específicos de LES como o anti-DNA de dupla fita (n=1) e o anti-Sm (n=2) ou se o paciente apresentasse o diagnóstico de LES definido pelo Colégio Americano de Reumatologia (n=0). Os prontuários médicos foram revisados para dados demográficos, clínicos e resultados de exames laboratoriais relacionados a hepatopatia e anticorpos específicos de HAI. Resultado: Títulos moderados ou alto (> 40 U) de anti-P foram encontrados em 9,7% (9/93) dos pacientes com HAI e em nenhum dos controles (p = 0,003). No diagnóstico, os pacientes com anti-P positivo ou negativo apresentavam características demográficas/clínicas semelhantes, como a frequência de cirrose (44,4% vs 28,5%, p = 0,44) e exames laboratoriais relacionados a hepatite (p > 0,05). Entretanto, ao final do seguimento destes pacientes (média de 10,2 ± 4,9 anos), os pacientes positivos para anticorpos anti-P apresentaram uma maior frequência de cirrose quando comparados a pacientes negativos para anti-P (100% vs 60%, p = 0,04). Conclusão: a demonstração da presença do anticorpo anti-P em pacientes com HAI sem evidência de LES sugere um mecanismo comum de acometimento hepático nestas duas doenças. Além disso, a presença deste anticorpo parece predizer um pior prognóstico nos pacientes com HAI / Background: Autoantibodies to ribosomal P proteins (anti-rib P) are specific serological markers for systemic lupus erythematosus (SLE) and are associated with liver involvement in this disease. The similarity in autoimmune background between autoimmune hepatitis (AIH) and SLE- associated hepatitis raises the possibility that anti-rib P antibodies might also have relevance in AIH. Aims: To evaluate the frequency and clinical significance of anti-rib P antibodies in a large AIH cohort. Methods: Sera obtained at diagnosis of 96 AIH patients and of 82 healthy controls were tested for IgG anti-ribosomal P protein by ELISA. All of the sera were also screened for other lupus-specific autoantibodies, three patients with the presence of anti-dsDNA (n=1) and anti-Sm (n = 2) were excluded. Results: Moderate to high titers (> 40 U) of anti-rib P antibody were found in 9.7% (9/93) of the AIH patients and none of the controls (P = 0.003). At presentation, AIH patients with and without anti-rib P antibodies had similar demographic/clinical features, including the frequency of cirrhosis (44.4% vs. 28.5%, P = 0.44), hepatic laboratorial findings (p > 0.05). Importantly, at the final observation (follow-up period 10.2 ± 4.9 years), the AIH patients with anti-rib P had a significantly higher frequency of cirrhosis compared to the negative group (100% vs. 60%, P = 0.04). Conclusion: The novel demonstration of anti-rib P in AIH patients without clinical or laboratory evidence of SLE suggests a common underlying mechanism targeting the liver in these two diseases. In addition, this antibody appears to predict the patients with worse AIH prognoses