Post-acute COVID-19 in three doses vaccinated autoimmune rheumatic diseases patients: frequency and pattern of this condition

Abstract Background Data on post-acute COVID-19 in autoimmune rheumatic diseases (ARD) are scarce, focusing on a single disease, with variable definitions of this condition and time of vaccination. The aim of this study was to evaluate the frequency and pattern of post-acute COVID-19 in vaccinated patients with ARD using established diagnosis criteria. Methods Retrospective evaluation of a prospective cohort of 108 ARD patients and 32 non-ARD controls, diagnosed with SARS-CoV-2 infection (RT-PCR/antigen test) after the third dose of the CoronaVac vaccine. Post-acute COVID-19 (≥ 4 weeks and > 12 weeks of SARS-CoV-2 symptoms) were registered according to the established international criteria. Results ARD patients and non-ARD controls, balanced for age and sex, had high and comparable frequencies of ≥ 4 weeks post-acute COVID-19 (58.3% vs. 53.1%, p = 0.6854) and > 12 weeks post-acute COVID-19 (39.8% vs. 46.9%, p = 0.5419). Regarding ≥ 4 weeks post-acute COVID-19, frequencies of ≥ 3 symptoms were similar in ARD and non-ARD controls (54% vs. 41.2%, p = 0.7886), and this was also similar in > 12 weeks post-acute COVID-19 (68.3% vs. 88.2%, p = 0.1322). Further analysis of the risk factors for ≥ 4 weeks post-acute COVID-19 in ARD patients revealed that age, sex, clinical severity of COVID-19, reinfection, and autoimmune diseases were not associated with this condition (p > 0.05). The clinical manifestations of post-acute COVID-19 were similar in both groups (p > 0.05), with fatigue and memory loss being the most frequent manifestations. Conclusion We provide novel data demonstrating that immune/inflammatory ARD disturbances after third dose vaccination do not seem to be a major determinant of post-acute COVID-19 since its pattern is very similar to that of the general population. Clinical Trials platform (NCT04754698).

HLA-B27 positivity in a large miscegenated population of 5,389,143 healthy blood marrow donors in Brazil

Abstract Background The prevalence of HLA-B27 gene positivity in healthy Caucasian communities varies between 8 and 14%. However, there is a lack of information in countries with a high rate of miscegenation, such as Brazil. Aim To estimate the frequency of HLA-B27 in the Brazilian general population using a large national registry database. Methods This is a cross-sectional ecological study using the Brazilian Registry of Volunteer Bone Marrow Donors (REDOME) database on HLA-B27 allelic frequency and proportion of positives of healthy donors (18-60 years old). Data were analyzed according to sex, age, race (by self-reported skin color recommended by the Brazilian Institute of Geography and Statistics - IBGE), and geographic region of residence. Results From 1994 to 2022, a total of 5,389,143 healthy bone marrow donors were included. The overall positivity for HLA-B27 was 4.35% (CI 95% 4.32-4.37%), regardless of sex and age (57.2% were women, mean age was 41.7yo). However, there was a difference between races: 4.85% in Whites; 2.92% in Blacks; 3.76% in Pardos (Browns i.e. mixed races); 3.95% in Amarelos (Yellows i.e. Asian Brazilians); and 3.18% in Indigenous. There was also a difference regarding geographic region of residence (North: 3.62%; Northeast: 3.63%; Southeast: 4.29%; Midwest: 4.5% and 5.25% in South). The homozygosity rate for the HLA-B27 was 1.32% of all the positives and only 0.06% in the general population. Conclusions Our findings provide the first Brazilian national prevalence for HLA-B27 in 4.35%. There is a gradient gene positivity from North to South, suggesting that the genetic background related to the miscegenation due to colonization, slavery, and some later waves of immigration together with internal migratory flows, could explain our findings.

Brazilian recommendations for the use of nonsteroidal anti-inflammatory drugs in patients with axial spondyloarthritis

Abstract Spondyloarthritis (SpA) is a group of chronic inflammatory systemic diseases characterized by axial and/or peripheral joints inflammation, as well as extra-articular manifestations. Over some decades, nonsteroidal anti-inflammatory drugs (NSAIDs) have been the basis for the pharmacological treatment of patients with axial spondyloarthritis (axSpA). However, the emergence of the immunobiologic agents brought up the discussion about the role of NSAIDs in the management of these patients. The objective of this guideline is to provide recommendations for the use of NSAIDs for the treatment of axSpA. A panel of experts from the Brazilian Society of Rheumatology conducted a systematic review and meta-analysis of randomized clinical trials for 15 predefined questions. The Grading of Recommendations, Assessment, Development and Evaluation methodology to assess the quality of evidence and formulate recommendations were used, and at least 70% agreement of the voting panel was needed. Fourteen recommendations for the use of NSAIDs in the treatment of patients with axSpA were elaborated. The purpose of these recommendations is to support clinicians' decision making, without taking out his/her autonomy when prescribing for an individual patient.(AU)

Ankylosing spondylitis and psoriatic arthritis: revisiting screening of latent tuberculosis infection and its follow-up during anti-tumor necrosis factor therapy in an endemic area

OBJECTIVES: To retrospectively evaluate the performance and distinctive pattern of latent tuberculosis (TB) infection (LTBI) screening and treatment in patients with ankylosing spondylitis (AS) and psoriatic arthritis (PsA) under anti-tumor necrosis factor (TNF) therapy and determine the relevance of re-exposure and other risk factors for TB development. METHODS: A total of 135 and 83 patients with AS and PsA, respectively, were evaluated for LTBI treatment before receiving anti-TNF drugs via the tuberculin skin test (TST), chest radiography, and TB exposure history assessment. All subjects were evaluated for TB infection at 3-month intervals. RESULTS: The patients with AS were more often treated for LTBI than were those with PsA (42% versus 30%, p=0.043). The former also presented a higher frequency of TST positivity (93% versus 64%, p=0.002), although they had a lower frequency of exposure history (18% versus 52%, p=0.027) and previous TB (0.7% versus 6%, p=0.03). During follow-up [median, 5.8 years; interquartile range (1QR), 2.2-9.0 years], 11/218 (5%) patients developed active TB (AS, n=7; PsA, n=4). TB re-exposure was the main cause in seven patients (64%) after 12 months of therapy (median, 21.9 months; IQR, 14.2-42.8 months) and five LTBI-negative patients. TB was identified within the first year in four patients (36.3%) (median, 5.3 months; IQR, 1.2-8.8 months), two of whom were LTBI-positive. There was no difference in the TB-free survival according to the anti-TNF drug type/class; neither synthetic drug nor prednisone use was related to TB occurrence (p>0.05). CONCLUSION: Known re-exposure is the most critical factor for incident TB cases in spondyloarthritis. There are also some distinct features in AS and PsA LTBI screening, considering the higher frequency of LTBI and TST positivities in patients with AS. Annual risk reassessment taking into consideration these peculiar features and including the TST should be recommended for patients in endemic countries.

The Brazilian Society of Rheumatology guidelines for axial spondyloarthritis - 2019

Abstract Spondyloarthritis is a group of chronic inflammatory systemic diseases characterized by axial and/or peripheral joints inflammation, as well as extra-articular manifestations. The classification axial spondyloarthritis is adopted when the spine and/or the sacroiliac joints are predominantly involved. This version of recommendations replaces the previous guidelines published in May 2013. A systematic literature review was performed, and two hundred thirty-seven studies were selected and used to formulate 29 recommendations answering 15 clinical questions, which were divided into four sections: diagnosis, non-pharmacological therapy, conventional drug therapy and biological therapy. For each recommendation the level of evidence supporting (highest available), the strength grade according to Oxford, and the degree of expert agreement (inter-rater reliability) is informed. These guidelines bring evidence-based information on clinical management of axial SpA patients, including, diagnosis, treatment, and prognosis.

Systemic and localized infection by Candida species in patients with rheumatic diseases receiving anti-TNF therapy / Infecção sistêmica e localizada por Candida spp. em pacientes reumatológicos em terapia anti-TNF

ABSTRACT Objective: To evaluate the prevalence of systemic and localized infection by Candida species and its possible association with demographic, clinical and laboratory manifestations and therapy in patients with rheumatic diseases taking TNF blockers. Methods: Consecutive patients with rheumatic diseases receiving anti-TNF agents were included. The following risk factors up to four weeks prior to the study were analyzed: use of antibiotics, immunosuppressant drugs, hospitalization and invasive procedures. All subjects were evaluated for clinical complaints; specific blood cultures were obtained for fungi and blood samples were collected for Candida spp. detection by polymerase chain reaction. Results: 194 patients [67 with rheumatoid arthritis (RA), 47 with ankylosing spondylitis (AS), 36 with juvenile idiopathic arthritis (JIA), 28 with psoriatic arthritis and 16 with other conditions] were included. The average age of patients was 42 ± 16 years, with 68 (35%) male and mean disease duration of 15 ± 10 years. Sixty-four (33%) patients were receiving adalimumab, 59 (30%) etanercept and 71 (36%) infliximab. Eighty-one percent of patients were concomitantly taking immunosuppressant drugs. At the time of the study, only one (0.5%) patient had localized fungal infection (vaginal candidiasis). None of the patients included had systemic candidiasis with positive blood cultures for fungi or PCR positive for Candida spp. in peripheral blood sample. Conclusions: This was the first study to assess the prevalence of invasive and localized fungal disease by Candida in a significant number of patients with rheumatic diseases on anti-TNF therapy, and demonstrated low risk of candidiasis, despite the high prevalence of immunosuppressive drug use.

RESUMO Objetivo: Avaliar a prevalência de infecção sistêmica e localizada por Candida spp. e sua possível associação com dados demográficos, manifestações clínicas e laboratoriais e terapêutica em pacientes com doenças reumatológicas em uso de anti-TNF. Métodos: Foram incluídos pacientes consecutivos com doenças reumatológicas em uso de agentes anti-TNF. Foram analisados os seguintes fatores de risco até quatro semanas antes do estudo: uso de antibioticoterapia, imunossupressores, hospitalização e procedimentos invasivos. Todos foram avaliados para queixas clinicas, coletaram hemocultura específica para fungos e amostras de sangue para pesquisa de Candida spp. por reação em cadeia de polimerase. Resultados: Foram incluídos 194 pacientes [67 com artrite reumatoide (AR), 47 espondilite anquilosante (EA), 36 artrite idiopática juvenil (AIJ), 28 artrite psoriásica e 16 outros]. A média de idade era de 42 ± 16 anos, com 68 (35%) do sexo masculino e média de duração de doença de 15 ± 10 anos; 64 (33%) pacientes usavam adalimumabe, 59 (36%) etanercepte e 71 (36%) infliximabe; 81% faziam uso concomitante de imunossupressores. No momento do estudo, apenas um (0,5%) paciente apresentou infecção fúngica localizada (candidíase vaginal). Nenhum dos pacientes incluídos apresentou candidíase sistêmica com hemocultura positiva para fungos ou PCR positiva para Candida spp. em amostra de sangue periférico. Conclusões: Este foi o primeiro estudo que avaliou prevalência de doença fúngica invasiva e localizada por Candida em um expressivo número de pacientes reumatológicos em terapia anti-TNF e demonstrou baixo risco de candidíase, apesar da alta prevalência de uso de imunossupressores.

Baixos níveis de esclerostina: preditor de processo inflamatório persistente em pacientes com espondilite anquilosante sob terapia anti-TNF / Low sclerostin levels: a predictive marker of persistent inflammation in ankylosing spondylitis during anti-TNF therapy

Introdução: Baixas concentrações séricas de esclerostina foram descritas em pacientes com Espondilite Anquilosante (EA). No entanto, não existem dados sobre a importância deste inibidor da via de sinalização Wnt em pacientes com EA durante o tratamento com anti fator de necrose tumoral alfa (TNFa). Objetivos: Avaliar longitudinalmente os níveis séricos de esclerostina e sua associação com inflamação e densidade mineral óssea (DMO) em pacientes com EA em tratamento com anti-TNFa. Métodos: Trinta pacientes com EA em atividade foram avaliados no início, 6 e 12 meses, após terapia anti-TNFa em relação aos parâmetros clínicos (BASDAI, BASFI, BASMI e ASQoL), marcadores inflamatórios e dano radiológico basal (mSASSS). Trinta indivíduos saudáveis pareados por idade e sexo constituíram o grupo controle. As análises laboratoriais de esclerostina e da ligação de esclerostina ao receptor LRP6 e a DMO foram realizadas nos pacientes nos mesmos períodos de avaliação e comparadas aos controles. Resultados: Na avaliação inicial, pacientes com EA apresentavam menores concentrações séricas de esclerostina [60,5 (32,7) vs. 96,7 (52,9) pmol/l,P=0,002] e níveis similares de ligação de esclerostina ao receptor LRP6 (P=0,387) em relação aos controles. Foi observado melhora do BASDAI, BASFI, BASMI, ASQoL comparando tempo basal vs. 6 vs. 12 meses (P<0,01). Concomitantemente, observou-se um aumento gradual da DMO da coluna lombar (P<0,001) e no início do estudo os pacientes apresentavam uma correlação positiva entre avaliação radiológica basal (mSASSS) e a DMO da coluna lombar (r=0,468, P<0,01). Foi observada também uma redução dos marcadores inflamatórios comparando tempo basal vs. 6 vs. 12 meses (P<0,01). Os níveis de esclerostina aumentaram progressivamente após o tratamento com anti-TNFa [60,5 (32,7) vs. 67,1 (31,9) vs. 72,7 (32,3) pmol/l, P<0,001]...

Introduction: Sclerostin levels have been reported to be low in ankylosing spondylitis (AS), but there is no data regarding the possible role of this Wnt inhibitor during anti tumor necrosis factor alpha (TNFa) therapy. Objectives: The present study longitudinally evaluated sclerostin levels, inflammatory markers and bone mineral density (BMD) in AS patients under anti-TNFa therapy. Methods: Thirty active AS patients were assessed at baseline, 6 and 12 months after anti-TNFa therapy regarding clinical parameters (BASDAI, BASFI, BASMI and ASQoL), inflammatory markers, BMD and baseline radiographic damage (mSASSS). Thirty age- and sex-matched healthy individuals comprised the control group. Patients' sclerostin levels, sclerostin binding LRP6 and BMD were evaluated at the same time points and compared to controls. Results: At baseline, AS patients had lower sclerostin levels [60.5 (32.7) vs. 96.7 (52.9) pmol/l, P=0.002] and comparable sclerostin binding to LRP6 (P=0.387) than controls. Improvement of BASDAI, BASFI, BASMI, ASQoL was observed at baseline vs. 6 vs. 12 months (P<0.01). Concomitantly, a gradual increase in spine BMD (P<0.001) and a positive correlation between baseline mSASSS and spine BMD was found (r=0.468, P<0.01). Inflammatory parameters reduction was observed comparing baseline vs. 6 vs. 12 months (P<0.01). Sclerostin levels progressively increased [60.5 (32.7) vs. 67.1 (31.9) vs. 72.7 (32.3) pmol/l, P<0.001] after anti-TNFa treatment. At 12 months, the sclerostin levels remained significantly lower in patients compared to controls [72.7 (32.3) vs. 96.70 (52.85) pmol/l, P=0.038]. Moreover, sclerostin serum levels at 12 months were lower in the 10 patients with high CRP (=5mg/l) compared to the other 20 patients with normal CRP (P=0.004)...

Intestinal microsporidiosis: a hidden risk in rheumatic disease patients undergoing anti-tumor necrosis factor therapy combined with disease-modifying anti-rheumatic drugs?

OBJECTIVE: Immunosuppressed patients are at risk of microsporidiosis, and this parasitosis has an increased rate of dissemination in this population. Our objective was to evaluate the presence of microsporidiosis and other intestinal parasites in rheumatic disease patients undergoing anti-tumor necrosis factor/disease-modifying anti-rheumatic drug treatment. METHODS: Ninety-eight patients (47 with rheumatoid arthritis, 31 with ankylosing spondylitis and 11 with psoriatic arthritis) and 92 healthy control patients were enrolled in the study. Three stool samples and cultures were collected from each subject. RESULTS: The frequency of microsporidia was significantly higher in rheumatic disease patients than in control subjects (36 vs. 4 percent, respectively; p<0.0001), as well as in those with rheumatic diseases (32 vs. 4 percent, respectively; p<0.0001), ankylosing spondylitis (45 vs. 4 percent, respectively; p<0.0001) and psoriatic arthritis (40 vs. 4 percent, respectively; p<0.0001), despite a similar social-economic class distribution in both the patient and control groups (p = 0.1153). Of note, concomitant fecal leukocytes were observed in the majority of the microsporidia-positive patients (79.5 percent). Approximately 80 percent of the patients had gastrointestinal symptoms, such as diarrhea (26 percent), abdominal pain (31 percent) and weight loss (5 percent), although the frequencies of these symptoms were comparable in patients with and without this infection (p>0.05). Rheumatoid arthritis, ankylosing spondylitis and psoriatic arthritis disease activity parameters were comparable in both groups (p>0.05). The duration of anti-tumor necrosis factor/disease-modifying anti-rheumatic drugs and glucocorticoid use were also similar in both groups. CONCLUSION: We have documented that microsporidiosis with intestinal mucosa disruption is frequent in patients undergoing concomitant anti-tumor necrosis factor/disease-modifying anti-rheumatic drug therapy. Impaired host defenses due to the combination of the underlying disease and the immunosuppressive therapy is the most likely explanation for this finding, and this increased susceptibility reinforces the need for the investigation of microsporidia and implementation of treatment strategies in this population.

Pesquisa de autoanticorpos em pacientes com artrite psoriásica sob terapia anti-TNFα / Autoantibodies in patients with psoriatic arthritis on anti-TNFα therapy

INTRODUÇÃO: A terapia imunobiológica anti-TNFα tem-se mostrado efetiva no tratamento de pacientes com artrite psoriásica (APs) refratária. No entanto, não está bem definido o risco de desenvolvimento de autoanticorpos comumente encontrados nas doenças reumatológicas em pacientes com APs na vigência desse tratamento. OBJETIVO: avaliar a indução de autoanticorpos específicos durante a terapia anti-TNFα em pacientes com APs. PACIENTES E MÉTODOS: Foram analisadas amostras de soro de 23 pacientes com APs (mulheres: 61 por cento, idade: 45,04 ± 12,68 anos, quadro poliarticular: 69,6 por cento, duração da doença: 13,3 ± 7,7 anos, infliximabe: 82,60 por cento) obtidas imediatamente antes (basal) e cerca de um ano após a introdução da terapia anti-TNF (última amostra) (385 ± 131,45 dias). A pesquisa incluiu a detecção de anticorpos antinucleares (ANA) e anticorpos para dsDNA (imunofluorescência indireta em células Hep-2 e em Crithidia luciliae, respectivamente); RNP e Sm (hemaglutinação passiva); Ro/SS-A e/ou La/SS-B, cromatina, histona, peptídeo citrulinado (CCP) e cardiolipina (ELISA). RESULTADOS: A pesquisa basal de ANA revelou positividade em 47,8 por cento dos pacientes, com predomínio do padrão nuclear homogêneo (81,8 por cento). Todas as amostras de soro testadas foram negativas para fator reumatoide e anticorpos anticardiolipina, RNP, Sm, Ro/SS-A, La/SS-B, histona e dsDNA, enquanto dois pacientes apresentaram positividade para anticromatina e um para anti-CCP. Todas as amostras de ANA positivas no tempo basal, exceto uma, mantiveram essa reatividade após a introdução da terapia anti-TNF. Reatividade "de novo" ANA foi observada em quatro dos pacientes originalmente negativos (33,3 por cento). Anticorpos anti-Ro/SS-A, La/SS-B, cardiolipina, histona, dsDNA e fator reumatoide foram sistematicamente negativos em todas as amostras finais de soro testadas e positividade anticromatina foi detectada em outros três...

INTRODUCTION: Anti-TNFα therapy has been effective in the treatment of patients with refractory psoriatic arthritis (PSA). However, the risk of developing autoantibodies commonly found in rheumatic diseases in PSA patients undergoing this therapy is not clear. OBJECTIVE: To evaluate the induction of specific autoantibodies after anti-TNFα therapy in PSA patients. PATIENTS AND METHODS: Serum samples from 23 PSA patients (women: 61 percent, age: 45.04 ± 12.68 years, polyarticular: 69.6 percent, disease duration: 13.3 ± 7.7 years, infliximab: 82.60 percent) obtained immediately before (baseline) and approximately one year after the introduction of anti-TNF therapy (last sample) (385 ± 131.45 days), were analyzed. The analysis included detection of antinuclear antibodies (ANA) and anti-dsDNA antibodies (indirect immunofluorescence on Hep-2 cells and Crithidia luciliae, respectively); anti-RNP and anti-Sm (passive hemagglutination); and anti-Ro/ SS-A and/or anti-La/SS-B, anti-chromatin, anti-histones, anti-citrullinated peptide (CCP), and anti-cardiolipin (ELISA) antibodies. RESULTS: At baseline, ANA was positive in 47.8 percent of patients, with predominance of homogeneous nuclear pattern (81.8 percent). All baseline serum samples were negative for rheumatoid factor and antibodies to cardiolipin, RNP, Sm, Ro/SS-A, anti-La/SS-B, anti-histone, and anti-dsDNA antibodies, while two patients were positive for anti-chromatin and one for anti-CCP. All ANA-positive samples at baseline, except for one, remained positive after the introduction of anti-TNF therapy; however, de novo ANA reactivity was observed in four originally negative patients (33.3 percent). Anti-Ro/SS-A, La/SS-B, cardiolipin, histones, dsDNA, and rheumatoid factor antibodies remained negative in all final serum samples tested, and anti-chromatin positivity was detected in three other patients. CONCLUSION: Our findings have shown that anti-TNF therapy induced ANA positivity...

Complicações imediatas de 3.555 aplicações de agentes anti-TNFα / Immediate complications of 3, 555 injections of anti-TNFα

OBJETIVO: Avaliar as complicações imediatas da aplicação de agentes anti-TNFα no Centro de Dispensação de Medicação deAlto Custo do HC-FMUSP. PACIENTES E MÉTODOS: Foram incluídos todos os pacientes que receberam agentes anti-TNFα entre agosto/2007 e março/2009.As complicações imediatas (até 1 hora após o término da aplicação) foram classificadas em leves (cefaleia, rash, tontura, prurido, náuseas), moderadas (febre, urticária, palpitação, dor torácica, dispneia, variação da pressão arterial de 20 a 40 mmHg) ou graves (febre com calafrios, dispneia com sibilância, variação da pressão arterial > 40 mmHg). RESULTADOS: Foram avaliados 242 pacientes: 94 (39 por cento) com artrite reumatoide, 64 (26 por cento) com espondilite anquilosante, 32 (13 por cento) com artrite psoriásica, 26 (11 por cento) com artrite idiopática juvenil e 27 (11 por cento) com outros diagnósticos. O número total de aplicações foi de 3.555, sendo 992 (28 por cento) de adalimumabe, 1.546 (43 por cento) de etanercepte e 1.017 (29 por cento) de infliximabe. Complicações imediatas foram observadas em 39/242 (16 por cento) pacientes. As complicações ocorreram em 45/3.555 (1,2 por cento) aplicações. Estas foram mais frequentes com infliximabe comparado com adalimumabe (3,7 por cento vs. 0,5 por cento, P < 0,0001), e com etanercepte (3,7 por cento vs. 0,25 por cento, P < 0,0001). As complicações foram: leves 14/45 (31 por cento), moderadas 21/45 (47 por cento) e graves 10/45 (22 por cento); ocorreram principalmente nos primeiros seis meses de tratamento (56 por cento) e nas aplicações endovenosas, predominantemente na primeira hora de infusão (76 por cento). CONCLUSÃO: As reações agudas, apesar de raras, são potencialmente graves e ocorrem principalmente nas primeiras aplicações tanto no uso de medicações endovenosas como de subcutâneas...

OBJECTIVE: To evaluate the immediate complications of anti-TNFα drugs at the "Center for Dispensation of High Cost Medications" of HC-FMUSP. PATIENTS AND METHODS: All patients who received anti-TNFα agents between August 2007 and March 2009 were included in this study. Immediate complications (up to 1 hour after the injection) were classified as mild (headache, rash, dizziness, itching, nausea), moderate (fever, urticaria, palpitation, chest pain, dyspnea, blood pressure variations between 20 and 40 mmHg), or severe (fever with chills, dyspnea with wheezing, variations in blood pressure > 40 mmHg). RESULTS: Two hundred and forty-two patients were evaluated: 94 (39 percent) with rheumatoid arthritis, 64 (26 percent) with ankylosing spondylitis, 32 (13 percent) with psoriatic arthritis, 26 (11 percent) with juvenile idiopathic arthritis; and 27 (11 percent) with other diagnoses. A total of 3,555 injections were administered: 992 (28 percent) adalimumab, 1,546 (43 percent) etanercept, and 1,017 (29 percent) infliximab. Immediate adverse events were observed in 39/242 (16 percent) patients. Injectionrelated complications were observed in 46/3,555 (1.2 percent) injections. They were more common with infliximab than adalimumab (3.7 percent vs. 0.5 percent, P < 0.0001) and etanercept (3.7 percent vs. 0.25 percent, P < 0.0001). Complications were classified as mild 14/45 (31 percent), moderate 21/45 (47 percent), and severe 10/45 (22 percent), and occurred mainly in the first six months of treatment (56 percent) and after intravenous injections, especially (76 percent) in the first hour. CONCLUSION: Although rare, acute reactions can be severe, being observed more commonly after the initial injections, both intravenous and subcutaneous...