Abstract Objective To develop the second evidence-based Brazilian Society of Rheumatology consensus for diagnosis and treatment of lupus nephritis (LN). Methods Two methodologists and 20 rheumatologists from Lupus Comittee of Brazilian Society of Rheumatology participate in the development of this guideline. Fourteen PICO questions were defined and a systematic review was performed. Eligible randomized controlled trials were analyzed regarding complete renal remission, partial renal remission, serum creatinine, proteinuria, serum creatinine doubling, progression to end-stage renal disease, renal relapse, and severe adverse events (infections and mortality). The Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach was used to develop these recommendations. Recommendations required ≥82% of agreement among the voting members and were classified as strongly in favor, weakly in favor, conditional, weakly against or strongly against a particular intervention. Other aspects of LN management (diagnosis, general principles of treatment, treatment of comorbidities and refractory cases) were evaluated through literature review and expert opinion. Results All SLE patients should undergo creatinine and urinalysis tests to assess renal involvement. Kidney biopsy is considered the gold standard for diagnosing LN but, if it is not available or there is a contraindication to the procedure, therapeutic decisions should be based on clinical and laboratory parameters. Fourteen recommendations were developed. Target Renal response (TRR) was defined as improvement or maintenance of renal function (±10% at baseline of treatment) combined with a decrease in 24-h proteinuria or 24-h UPCR of 25% at 3 months, a decrease of 50% at 6 months, and proteinuria < 0.8 g/24 h at 12 months. Hydroxychloroquine should be prescribed to all SLE patients, except in cases of contraindication. Glucocorticoids should be used at the lowest dose and for the minimal necessary period. In class III or IV (±V), mycophenolate (MMF), cyclophosphamide, MMF plus tacrolimus (TAC), MMF plus belimumab or TAC can be used as induction therapy. For maintenance therapy, MMF or azathioprine (AZA) are the first choice and TAC or cyclosporin or leflunomide can be used in patients who cannot use MMF or AZA. Rituximab can be prescribed in cases of refractory disease. In cases of failure in achieving TRR, it is important to assess adherence, immunosuppressant dosage, adjuvant therapy, comorbidities, and consider biopsy/rebiopsy. Conclusion This consensus provides evidence-based data to guide LN diagnosis and treatment, supporting the development of public and supplementary health policies in Brazil. evidencebased evidence LN. . (LN) 2 guideline performed remission doubling endstage end stage disease relapse infections mortality. mortality mortality) Assessment GRADE (GRADE 82 ≥82 favor conditional intervention diagnosis, (diagnosis opinion involvement but procedure parameters developed TRR (TRR ±10% 10 (±10 24h 24 25 months 50 08 0 8 0. g24 g g/2 1 period ±V, V ±V , (±V) MMF, (MMF) cyclophosphamide TAC, (TAC) therapy AZA (AZA adherence dosage biopsyrebiopsy rebiopsy biopsy/rebiopsy Brazil (LN ≥8 ±10 (±1 5 g2 g/ (±V (MMF (TAC ≥ ±1 (± ± (

Abstract Introduction Seasonal influenza A (H3N2) virus is an important cause of morbidity and mortality in the last 50 years in population that is greater than the impact of H1N1. Data assessing immunogenicity and safety of this virus component in juvenile systemic lupus erythematosus (JSLE) is lacking in the literature. Objective To evaluate short-term immunogenicity and safety of influenza A/Singapore (H3N2) vaccine in JSLE. Methods 24 consecutive JSLE patients and 29 healthy controls (HC) were vaccinated with influenza A/Singapore/ INFIMH-16-0019/2016(H3N2)-like virus. Influenza A (H3N2) seroprotection (SP), seroconversion (SC), geometric mean titers (GMT), factor increase in GMT (FI-GMT) titers were assessed before and 4 weeks post-vaccination. Disease activity, therapies and adverse events (AE) were also evaluated. Results JSLE patients and controls were comparable in current age [14.5 (10.1–18.3) vs. 14 (9–18.4) years, p = 0.448] and female sex [21 (87.5%) vs. 19 (65.5%), p = 0.108]. Before vaccination, JSLE and HC had comparable SP rates [22 (91.7%) vs. 25 (86.2%), p = 0.678] and GMT titers [102.3 (95% CI 75.0–139.4) vs. 109.6 (95% CI 68.2–176.2), p = 0.231]. At D30, JSLE and HC had similar immune response, since no differences were observed in SP [24 (100%) vs. 28 (96.6%), p = 1.000)], SC [4 (16.7%) vs. 9 (31.0%), p = 0.338), GMT [162.3 (132.9–198.3) vs. 208.1 (150.5–287.8), p = 0.143] and factor increase in GMT [1.6 (1.2–2.1) vs. 1.9 (1.4–2.5), p = 0.574]. SLEDAI-2K scores [2 (0–17) vs. 2 (0–17), p = 0.765] and therapies remained stable throughout the study. Further analysis of possible factors influencing vaccine immune response among JSLE patients demonstrated similar GMT between patients with SLEDAI < 4 compared to SLEDAI ≥ 4 ( p = 0.713), as well as between patients with and without current use of prednisone ( p = 0.420), azathioprine ( p = 1.0), mycophenolate mofetil ( p = 0.185), and methotrexate ( p = 0.095). No serious AE were reported in both groups and most of them were asymptomatic (58.3% vs. 44.8%, p = 0.958). Local and systemic AE were alike in both groups ( p > 0.05). Conclusion This is the first study that identified adequate immune protection against H3N2-influenza strain with additional vaccine-induced increment of immune response and an adequate safety profile in JSLE. ( www.clinicaltrials.gov , NCT03540823). H3N2 HN H N (H3N2 5 H1N1 (JSLE literature shortterm short term ASingapore Singapore (HC INFIMH160019/2016H3N2like INFIMH1600192016H3N2like INFIMHHNlike INFIMH 16 0019/2016 like 0019 2016 SP, (SP) SC, (SC) GMT, (GMT) FIGMT FI (FI-GMT postvaccination. postvaccination post vaccination. vaccination post-vaccination activity (AE evaluated 14.5 145 [14. 10.1–18.3 101183 10 1 18 3 (10.1–18.3 vs 9–18.4 9184 (9–18.4 0.448 0448 0 448 21 87.5% 875 87 (87.5% 65.5%, 655 65.5% 65 (65.5%) 0.108. 0108 0.108 . 108 0.108] 22 91.7% 917 91 7 (91.7% 86.2%, 862 86.2% 86 (86.2%) 0.678 0678 678 102.3 1023 102 [102. 95% 95 (95 75.0–139.4 7501394 75 139 1096 109 6 109. 68.2–176.2, 6821762 68.2–176.2 68 176 68.2–176.2) 0.231. 0231 0.231 231 0.231] D30 D 100% 100 (100% 96.6%, 966 96.6% 96 (96.6%) 1.000, 1000 1.000 000 1.000)] [ 16.7% 167 (16.7% 31.0%, 310 31.0% 31 (31.0%) 0.338, 0338 0.338 338 0.338) 162.3 1623 162 [162. 132.9–198.3 13291983 132 198 (132.9–198.3 2081 208 208. 150.5–287.8, 15052878 150.5–287.8 150 287 8 (150.5–287.8) 0.143 0143 143 1.6 [1. 1.2–2.1 1221 (1.2–2.1 1. 1.4–2.5, 1425 1.4–2.5 (1.4–2.5) 0.574. 0574 0.574 574 0.574] SLEDAI2K SLEDAIK 2K K 0–17 017 17 (0–17 0–17, 0.765 0765 765 0.713, 0713 0.713 713 0.713) 0.420, 0420 0.420 420 0.420) 1.0, 1.0 1.0) 0.185, 0185 0.185 185 0.185) 0.095. 0095 0.095 095 0.095) 58.3% 583 58 (58.3 44 44.8% 0.958. 0958 0.958 958 0.958) 0.05. 005 0.05 05 0.05) H3N2influenza HNinfluenza vaccineinduced induced wwwclinicaltrialsgov www clinicaltrials gov NCT03540823. NCT03540823 NCT NCT03540823) H3N (H3N H1N INFIMH160019 2016H3N2like 00192016 0019/201 001 201 (SP (SC (GMT 14. [14 10.1–18. 10118 (10.1–18. 9–18. 918 (9–18. 0.44 044 87.5 (87.5 65.5 (65.5% 010 0.10 91.7 (91.7 86.2 (86.2% 0.67 067 67 102. [102 (9 75.0–139. 750139 13 682176 68.2–176. 023 0.23 23 D3 (100 96.6 (96.6% 1.00 00 1.000) 16.7 (16.7 31.0 (31.0% 033 0.33 33 162. [162 132.9–198. 1329198 (132.9–198. 20 1505287 150.5–287. 15 (150.5–287.8 0.14 014 [1 1.2–2. 122 (1.2–2. 142 1.4–2. (1.4–2.5 057 0.57 57 0–1 01 (0–1 0.76 076 76 071 0.71 71 042 0.42 42 018 0.18 009 0.09 09 58.3 (58. 44.8 0.95 0.0 NCT0354082 INFIMH16001 HNlike 0019201 0019/20 10.1–18 1011 (10.1–18 9–18 (9–18 0.4 04 87. (87. 65. (65.5 0.1 91. (91. 86. (86.2 0.6 06 [10 75.0–139 75013 68217 68.2–176 02 0.2 (10 96. (96.6 16. (16. 31. (31.0 03 0.3 [16 132.9–198 132919 (132.9–198 150528 150.5–287 (150.5–287. 1.2–2 12 (1.2–2 1.4–2 (1.4–2. 0.5 0– (0– 0.7 07 58. (58 44. 0.9 0. NCT035408 INFIMH1600 001920 0019/2 10.1–1 101 (10.1–1 9–1 (9–1 (87 (65. (91 (86. 75.0–13 7501 6821 68.2–17 (1 (96. (16 (31. 132.9–19 13291 (132.9–19 15052 150.5–28 (150.5–287 1.2– (1.2– 1.4– (1.4–2 (0 (5 NCT03540 INFIMH160 00192 0019/ 10.1– (10.1– 9– (9– (8 (65 (86 75.0–1 750 682 68.2–1 (96 (31 132.9–1 1329 (132.9–1 1505 150.5–2 (150.5–28 1.2 (1.2 1.4 (1.4– NCT0354 INFIMH16 10.1 (10.1 (6 75.0– 68.2– (3 132.9– (132.9– 150.5– (150.5–2 (1. (1.4 NCT035 INFIMH1 10. (10. 75.0 68.2 132.9 (132.9 150.5 (150.5– NCT03 75. 68. 132. (132. 150. (150.5 NCT0 (132 (150. (13 (150 (15

Abstract Objective Therapeutic targets in Idiopathic Inflammatory Myopathies (IIM) are based on the opinions of physicians/specialists, which may not reflect the main concerns of patients. The authors, therefore, assessed the outcome concerns of patients with IIM and compared them with the concerns of rheumatologists in order to develop an IIM outcome standard set. Methods Ninety-three IIM patients, 51 rheumatologists, and one physiotherapist were invited to participate. An open questionnaire was initially applied. The top 10 answers were selected and applied in a multiple-choice questionnaire, inquiring about the top 3 major concerns. Answers were compared, and the agreement rate was calculated. Concerns were gathered in an IIM outcome standard set with validated measures. Results The top three outcome concerns raised by patients were medication side effects/muscle weakness/prevention functionality loss. The top three concerns among rheumatologists were to prevent loss of functionality/to ensure the quality of life/to achieve disease remission. Other's outcomes concerns only pointed out by patients were muscle pain/diffuse pain/skin lesions/fatigue. The agreement rate between both groups was 41%. Assessment of these parameters guided the development of an IIM standard set which included Myositis Disease Activity Assessment Visual Analogue Scale/Manual Muscle Testing/fatigue and pain Global Visual Analogue Scale/Health Assessment Questionnaire/level of physical activity. Conclusion The authors propose a novel standard set to be pursued in IIM routine follow-up, which includes not only the main patients/rheumatologist outcome concerns but also additional important outcomes only indicated by patients. Future studies are necessary to confirm if this comprehensive approach will result in improved adherence and ultimately in better assistance.

Abstract Background: Urinary parameters, anti-dsDNA antibodies and complement tests were explored in patients with childhood-Systemic Lupus Erythematosus (cSLE) early-onset lupus nephritis (ELN) from a large multicenter cohort study. Methods: Clinical and laboratory features of cSLE cases with kidney involvement at presentation, were reviewed. Disease activity parameters including SLEDAI-2 K scores and major organ involvement at onset and follow up, with accrued damage scored by SLICC-DI, during last follow up, were compared with those without kidney involvement. Autoantibodies, renal function and complement tests were determined by standard methods. Subjects were grouped by presence or absence of ELN. Results: Out of the 846 subjects enrolled, mean age 11.6 (SD 3.6) years; 427 (50.5%) had ELN. There was no significant difference in the ELN proportion, according to onset age, but ELN frequency was significantly higher in non-Caucasians (p = 0.03). Hematuria, pyuria, urine casts, 24-h proteinuria and arterial hypertension at baseline, all had significant association with ELN outcome (p < 0.001). With a similar follow up time, there were significantly higher SLICC-DI damage scores during last follow up visit (p = 0.004) and also higher death rates (p < 0.0001) in those with ELN. Low C3 (chi-square test, p = 0.01), but not C3 levels associated significantly with ELN. High anti-dsDNA antibody levels were associated with ELN (p < 0.0001), but anti-Sm, anti-RNP, anti-Ro, anti-La antibodies were not associated. Low C4, C4 levels, low CH50 and CH50 values had no significant association. High erythrocyte sedimentation rate (ESR) was associated with the absence of ELN (p = 0.02). Conclusion: The frequency of ELN was 50%, resulting in higher morbidity and mortality compared to those without ELN. The urinary parameters, positive anti-dsDNA and low C3 are reliable for discriminating ELN.

Abstract Objective: To evaluate prevalence, clinical manifestations, laboratory abnormalities, treatment and outcome in a multicenter cohort of childhood-onset systemic lupus erythematosus (cSLE) patients with and without panniculitis. Methods: Panniculitis was diagnosed due to painful subcutaneous nodules and/or plaques in deep dermis/subcutaneous tissues and lobular/mixed panniculitis with lymphocytic lobular inflammatory infiltrate in skin biopsy. Statistical analysis was performed using Bonferroni correction(p < 0.004). Results: Panniculitis was observed in 6/847(0.7%) cSLE. Painful subcutaneous erythematosus and indurated nodules were observed in 6/6 panniculitis patients and painful subcutaneous plaques in 4/6. Generalized distribution was evidenced in 3/6 and localized in upper limbs in 2/6 and face in 1/6. Cutaneous hyperpigmentation and/or cutaneous atrophy occurred in 5/6. Histopathology features showed lobular panniculitis without vasculitis in 5/6(one of them had concomitant obliterative vasculopathy due to antiphospholipid syndrome) and panniculitis with vasculitis in 1/6. Comparison between cSLE with panniculitis and 60 cSLE without panniculitis with same disease duration [2.75(0-11.4) vs. 2.83(0-11.8) years,p = 0.297], showed higher frequencies of constitutional involvement (67% vs. 10%,p = 0.003) and leukopenia (67% vs. 7%,p = 0.002). Cutaneous atrophy and hyperpigmentation occurred in 83% of patients. Conclusions: Panniculitis is a rare skin manifestation of cSLE occurring in the first three years of disease with considerable sequelae. The majority of patients have concomitant mild lupus manifestations.

Abstract Objective: To evaluate sexual function female adolescents and young adults with juvenile idiopathic arthritis (JIA) and healthy controls. Methods: After exclusion, 21 female adolescent and young JIA patients and 25 healthy controls were selected for this study. Sexual function was assessed by the Sexual Quotient Questionnaire for Females (SQQ-F) score, which is a validated tool and adapted for Brazilian Portuguese language. Demographic data, JIA clinical/laboratory parameters and treatment were also assessed. Results: The median current age [26.5 (17-38.1) vs. 29.3 (19.7-35.8) years, p = 0.700)] as well as age at the first sexual activity [18 (14-30) vs. 17 (10-24) years, p = 0.158] were similar in JIA patients and healthy controls. The median of SQQ-F score was alike in both groups [75.9 (50-92) vs. 78.2 (58-94), p = 0.529], as well as frequencies of sexual dysfunction (14% vs. 12%, p = 1.000). The frequencies of all sexual domains (desire/sexual fantasies, desire/interest, arousal/foreplay, arousal/lubrication, arousal/in tune with partner, penetration/relaxation, pain/penetration, desire/involvement, orgasm and general satisfaction scores) were similar in JIA patients and healthy controls (p > 0.05). Conclusions: To our knowledge, this was the first study using a validated sexual score in a chronic arthritis population suggesting a low frequency of overall sexual dysfunction in young JIA patients. Future multicenter studies with a large sample will be necessary to confirm this finding.

Abstract Objective: To evaluate the frequency of anti-collagen type V in humans with early systemic sclerosis (SSc) compared to defined SSc patients and healthy controls, since collagen type V was shown to be overexpressed in early SSc patients’ skin and there is no data concerning the presence of this antibody in early stages of human SSc. Experimental studies showed that animal models immunized with collagen type V developed a disease similar to human systemic sclerosis (SSc), with antibodies production, mainly in early stages post-immunization. Methods: Eighty-one female SSc patients were included and divided into two groups: early-SSc (18 patients-EULAR Preliminary Criteria) and defined-SSc (63 patients-ACR Criteria 1980). The control group consisted of 19 healthy women age-matched to Early-SSc group. Anti-collagen type V was performed by ELISA. Data was analyzed by appropriate tests. Results: The prevalence of anti-collagen type V in early-SSc, defined-SSc and control groups was respectively 33, 17 and 5% (p = 0.07). SSc patients with anti-collagen type V had shorter disease duration compared to those without this antibody (8.8 ± 5.1 vs. 14.7 ± 8.9, p = 0.006). Likewise, early-SSc patients with anti-collagen V also had a shorter disease duration than patients negative for this antibody (4.6 ± 2.2 vs. 9.7 ± 5.2, p = 0.04). No association with clinical subsets or scleroderma antibodies specificities was observed (p > 0.05). Conclusion: The production of anti-collagen type V in SSc seems to be an early event independent of other antibodies specificities. Further studies are necessary to determine if the underlying mechanism for this chronology involves a primary immune response to abnormal expression of collagen type V.

Abstract Background: To evaluate human papillomavirus (HPV), Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) infections in juvenile idiopathic arthritis (JIA) patients. Methods: After exclusion, 33 female adolescent and young JIA patients (ILAR criteria) and 28 healthy controls were selected for this study. Demographic data, gynecological, sexual function, cervical cytology and histological abnormalities were evaluated. JIA clinical/laboratorial parameters and treatment were also assessed. HPV-DNA, CT-DNA and NG-DNA testing in cervical specimens were performed by Hybrid Capture 2 assays. Results: The mean current age was similar in JIA patients and controls (23.3 ± 6.24 vs. 26.1 ± 6.03 years, p = 0.09). The frequencies of sexual intercourse (76% vs. 89%, p = 0.201) and abnormal cervical cytology (24% vs. 11%, p = 0.201) were similar in JIA compared to controls. The higher frequency of HPV infection in JIA patients than controls (30% vs. 11%, p = 0.155) did not reach statistical significance. CT (0% vs. 7%, p = 0.207) and NG infections (0% vs. 4%, p = 0.459) were also alike in both groups. Further evaluation of JIA patients with abnormal and normal cervical cytology showed that the former group had a higher frequency of HPV infection (87% vs. 12%, p = 0.0002) with a low frequency of HPV vaccination (0% vs. 8%, p = 1.0). No differences were evidenced between these two JIA groups regarding demographic data, sexual function and clinical/laboratorial parameters. The frequencies of methotrexate (p =0.206) and biological agent use (p =0.238) were similar in both JIA groups. Conclusions: To our knowledge, this was the first study to assess lower genital infections in JIA patients allowing the identification of HPV as main cause of cervical dysplasia. Methotrexate and biological agents do not seem to increase risk of lower genital tract infections in JIA patients.

Abstract Objective: To evaluate autoimmune hepatitis (AIH) in a multicenter cohort of childhood-onset systemic lupus erythematosus (cSLE) patients. Methods: This retrospective multicenter study included 847 patients with cSLE, performed in 10 Pediatric Rheumatology services of São Paulo state, Brazil. AIH was defined according to the International Autoimmune Hepatitis Group criteria (IAHGC). The statistical analysis was performed using the Bonferroni's correction (p < 0.0033). Results: AIH in cSLE patients confirmed by biopsy was observed in 7/847 (0.8%) and all were diagnosed during adolescence. The majority occurred before or at cSLE diagnosis [5/7 (71%)]. Antinuclear antibodies were a universal finding, 43% had concomitantly anti-smooth muscle antibodies and all were seronegative for anti-liver kidney microsomal antibodies. All patients with follow-up ≥18 months (4/7) had complete response to therapy according to IAHGC. None had severe hepatic manifestations such as hepatic failure, portal hypertension and cirrhosis at presentation or follow-up. Further comparison of 7 cSLE patients with AIH and 28 without this complication with same disease duration [0 (0–8.5) vs. 0.12 (0–8.5) years, p = 0.06] revealed that the frequency of hepatomegaly was significantly higher in cSLE patients in the former group (71% vs. 11%, p = 0.003) with a similar median SLEDAI-2 K score [6 (0–26) vs. 7 (0–41), p = 0.755]. No differences were evidenced regarding constitutional involvement, splenomegaly, serositis, musculoskeletal, neuropsychiatric and renal involvements, and treatments in cSLE patients with and without AIH (p > 0.0033). Conclusions: Overlap of AIH and cSLE was rarely observed in this large multicenter study and hepatomegaly was the distinctive clinical feature of these patients. AIH occurred during adolescence, mainly at the first years of lupus and it was associated with mild liver manifestations.

Abstract Objective: To evaluate prevalence, clinical manifestations, laboratory abnormalities and treatment in a multicenter cohort study including 847 childhood-onset systemic lupus erythematosus (cSLE) patients with and without diffuse alveolar hemorrhage (DAH), as well as concomitant parameters of severity. Methods: DAH was defined as the presence of at least three respiratory symptoms/signs associated with diffuse interstitial/alveolar infiltrates on chest x-ray or high-resolution computer tomography and sudden drop in hemoglobin levels. Statistical analysis was performed using Bonferroni correction (p < 0.0022). Results: DAH was observed in 19/847 (2.2%) cSLE patients. Cough/dyspnea/tachycardia/hypoxemia occurred in all cSLE patients with DAH. Concomitant parameters of severity observed were: mechanical ventilation in 14/19 (74%), hemoptysis 12/19 (63%), macrophage activation syndrome 2/19 (10%) and death 9/19 (47%). Further analysis of cSLE patients at DAH diagnosis compared to 76 cSLE control patients without DAH with same disease duration [3 (1–151) vs. 4 (1–151) months, p = 0.335], showed higher frequencies of constitutional involvement (74% vs. 10%, p < 0.0001), serositis (63% vs. 6%, p < 0.0001) and sepsis (53% vs. 9%, p < 0.0001) in the DAH group. The median of disease activity score(SLEDAI-2 K) was significantly higher in cSLE patients with DAH [18 (5–40) vs. 6 (0–44), p < 0.0001]. The frequencies of thrombocytopenia (53% vs. 12%, p < 0.0001), intravenous methylprednisolone (95% vs. 16%, p < 0.0001) and intravenous cyclophosphamide (47% vs. 8%, p < 0.0001) were also significantly higher in DAH patients. Conclusions: This was the first study to demonstrate that DAH, although not a disease activity score descriptor, occurred in the context of significant moderate/severe cSLE flare. Importantly, we identified that this condition was associated with serious disease flare complicated by sepsis with high mortality rate.

Abstract Background: Interpretation of rituximab efficacy for refractory idiopathic inflammatory myopathies (IIM) is hampered by the absence of a uniform definition of refractory myositis and clinical response. Therefore, rigorous criteria of refractoriness, together with a homogenous definition of clinical improvement, were used to evaluate rituximab one-year response. Methods: A retrospective cohort study including 43 IIM (15 antisynthetase syndrome, 16 dermatomyositis, 12 polymyositis) was conducted. All patients had refractory disease (inadequate response to at least two immunosuppressives/immunomodulatories and no less than three months sequentially or concomitantly glucocorticoid tapering) criteria. Clinical/laboratory improvement at one-year was based on modified International Myositis Assessment & Clinical Studies Group (IMACS) core set measures. The patients received two infusions of rituximab (1 g each) at baseline, followed by repeated dose after 6 months. Baseline immunosuppressive therapy was maintained and glucocorticoid dose was tapered according to clinical/laboratory parameters. Results: Five patients had side effects at the first rituximab application and were excluded. Therefore, 38 out of 43 patients completed the one-year follow up. Almost 75% of the patients attained clinical and laboratory response after one-year. A significant reduction in median glucocorticoid dose (18.8 vs. 6.3 mg/day) was achieved and 42% patients were able to discontinue prednisone. In contrast, young individuals and patients with dysphagia had a tendency to be non-responders to rituximab. No severe infections were observed. Conclusion: This study provides convincing evidence that rituximab is an effective and safe therapy for refractory IIM.