Agreement between local and central anti-synthetase antibodies detection: results from the Classification Criteria of Anti-Synthetase Syndrome project biobank.

OBJECTIVES: The CLASS (Classification Criteria of Anti-Synthetase Syndrome) project is a large international multicentre study that aims to create the first data-driven anti-synthetase syndrome (ASSD) classification criteria. Identifying anti-aminoacyl tRNA synthetase antibodies (anti-ARS) is crucial for diagnosis, and several commercial immunoassays are now available for this purpose. However, using these assays risks yielding false-positive or false-negative results, potentially leading to misdiagnosis. The established reference standard for detecting anti-ARS is immunoprecipitation (IP), typically employed in research rather than routine autoantibody testing. We gathered samples from participating centers and results from local anti-ARS testing. As an "ad-interim" study within the CLASS project, we aimed to assess how local immunoassays perform in real-world settings compared to our central definition of anti-ARS positivity. METHODS: We collected 787 serum samples from participating centres for the CLASS project and their local anti-ARS test results. These samples underwent initial central testing using RNA-IP. Following this, the specificity of ARS was reconfirmed centrally through ELISA, line-blot assay (LIA), and, in cases of conflicting results, protein-IP. The sensitivity, specificity, positive likelihood ratio and positive and negative predictive values were evaluated. We also calculated the inter-rater agreement between central and local results using a weighted κ co-efficient. RESULTS: Our analysis demonstrates that local, real-world detection of anti-Jo1 is reliable with high sensitivity and specificity with a very good level of agreement with our central definition of anti-Jo1 antibody positivity. However, the agreement between local immunoassay and central determination of anti-non-Jo1 antibodies varied, especially among results obtained using local LIA, ELISA and "other" methods. CONCLUSIONS: Our study evaluates the performance of real-world identification of anti-synthetase antibodies in a large cohort of multi-national patients with ASSD and controls. Our analysis reinforces the reliability of real-world anti-Jo1 detection methods. In contrast, challenges persist for anti-non-Jo1 identification, particularly anti-PL7 and rarer antibodies such as anti-OJ/KS. Clinicians should exercise caution when interpreting anti-synthetase antibodies, especially when commercial immunoassays test positive for non-anti-Jo1 antibodies.

Cancer-associated myositis before and after the COVID-19 pandemic onset: a changing trend.

OBJECTIVES: During the COVID-19 pandemic, there was a significant impact on the management of non-COVID-19 related diseases, potentially increasing the incidence of paraneoplastic syndromes such as cancer-associated myositis (CAM).The aim of this study is to determine the incidence of CAM in our cohort before and after the COVID-19 pandemic onset. METHODS: We included patients with idiopathic inflammatory myopathy (IIM), diagnosed between June 2016 and June 2023. The patients were divided into two groups according to the date of IIM diagnosis. RESULTS: We included 132 patients; 65.1% (n=86) were diagnosed prior to and 34.9% (n=46) after the COVID-19 pandemic. The most common IIM was dermatomyositis (DM) before and after the COVID-19 pandemic onset (p=0.750). The most frequent myositis-specific antibody (MSA) before the COVID-19 pandemic was anti-Mi2 (15.1%). After the COVID-19 pandemic onset, anti-TIF1γ was the most common MSA (21.7%), with a significantly higher relative prevalence (p=0.006). The incidence of CAM was significantly higher after the COVID-19 pandemic onset (11 vs. 3 new cases, p<0.002). Patients with CAM more frequently had anti-TIF1γ-positivity (p<0.001) and a diagnosis after the pandemic (p=0.001) than non-CAM-IIM patients. No significant differences were found regarding vaccination status or previous COVID-19 infection in CAM and non-CAM-IIM patients. Diagnosis after the COVID-19 pandemic was an independent predictor of CAM among IIM patients (OR 0.012, 95% CI 0.000-0.400, p=0.013), regardless of age, sex or previous COVID-19 infection. CONCLUSIONS: There was a significant increase in the incidence of CAM after the COVID-19 pandemic. IIM diagnosis after the COVID-19 pandemic was an independent predictor of CAM.

Idiopathic inflammatory myopathies: one year in review 2023.

Idiopathic inflammatory myopathies are a group of rare, autoimmune, diseases typically involving striate muscle and also variously affecting several other systems or organs, such as joints, skin, lungs, heart and gastrointestinal tract. IIM are mainly characterised by subacute onset and chronic course and are burdened by significant morbidity and mortality. Despite the rarity of these conditions, several efforts have been undertaken in the last years to better understand their pathogenesis, as well as to achieve a more precise classification and to define the optimal therapeutic approach. The aim of this review is to provide an up-to-date digest of the most relevant studies published on this topic over the last year.

Anxiety and depression in patients with giant cell arteritis.

Objectives: To compare the prevalence of anxiety and depression in patients with GCA with that in the general population, using the Hospital Anxiety and Depression Scale (HADS), and to identify independent predictors of these psychiatric manifestations in patients with GCA. Methods: We conducted a cross-sectional study including all patients diagnosed with GCA followed during 1 year in a vasculitis outpatient clinic. The HADS and 36-item Short Form (SF-36) questionnaires were prospectively collected. Patients' HADS results were compared with an age- and gender-matched control group. HADS anxiety (HADS-A) and HADS depression (HADS-D) scores between 8 and 10 defined possible anxiety and depression and ≥11 defined probable anxiety and depression, respectively. Results: We included 72 patients and 288 controls. Compared with controls, patients with GCA had a statistically significant higher prevalence of HADS-A ≥8 (48.6% vs 26.4%), HADS-A ≥11 (30.6% vs 12.2%) and HADS-D ≥11 (33.3% vs 18.1%). GCA was an independent predictor of HADS-A ≥8 [odds ratio (OR) 3.3 (95% CI 1.9, 5.9)], HADS-A ≥11 [OR 3.8 (95% CI 2.0, 7.4)] and HADS-D ≥11 [OR 2.6 (95% CI 1.4, 4.7)]. Among patients with GCA, a negative correlation was observed between HADS-A/D and SF-36 mental health scores (r = -0.780 and r = -0.742, respectively). Glucocorticoid therapy was a predictor of HADS-A ≥8 [OR 10.4 (95% CI 1.2, 94.2)] and older age of HADS-D ≥8 [OR 1.2 (95% CI 1.1, 1.3)] and HADS-D ≥11 [OR 1.1 (95% CI 1.0, 1.2)]. Conclusions: Compared with the general population, patients with GCA have a higher prevalence of anxiety and depression and GCA is an independent predictor of these symptoms. Glucocorticoid treatment and older age are predictors of anxiety and depression, respectively, in patients with GCA.

Systematic literature review to inform the Portuguese recommendations for the management of Raynaud's phenomenon and digital ulcers in systemic sclerosis and other connective tissue diseases.

OBJECTIVE: To perform a systematic literature review (SLR) aimed at evaluating the efficacy and safety of pharmacological and non-pharmacological treatments for Raynaud's phenomenon (RP) and digital ulcers (DU) in patients with systemic sclerosis (SSc) and other connective tissue diseases (CTD), in order to inform the Portuguese recommendations for managing RP and DU in these patients. METHODS: A SLR was conducted until May 2022 to identify studies assessing the efficacy and safety of pharmacological and non-pharmacological interventions for RP and DU in SSc and other CTD. Eligible study designs included randomized controlled trials (RCTs), controlled clinical trials, and their extensions for assessing efficacy and safety of interventions. Observational studies with a comparator were included for evaluating the efficacy and safety of non-pharmacological interventions and safety of pharmacological interventions. The risk of bias of each study was assessed using standard tools. RESULTS: Out of 71 publications meeting the inclusion criteria, 59 evaluated pharmacological and 12 non-pharmacological interventions. We found moderate quality evidence supporting the efficacy of calcium channel blockers, phosphodiesterase-5 inhibitors, and intravenous prostacyclin analogues in reducing RP frequency, severity, and duration. Intravenous iloprost had a small to moderate effect size in improving DU healing. Phosphodiesterase-5 inhibitors were effective in reducing total DU count, new DU occurrence, and enhancing DU healing. Bosentan effectively prevented new DU in SSc patients. No new safety concerns were associated with these treatments. The studies on non-pharmacological interventions were, in general, of low quality, and had a small sample size. Warming measures decreased frequency and duration of RP attacks; laser therapy improved RP-related outcomes; local oxygen-ozone therapy improved RP outcomes as an add-on therapy; bone marrow mononuclear cell implantation improved DU-associated pain; periarterial sympathectomy and vascular bypass reduced DU number and finger amputation risk. CONCLUSION: The available evidence supports the efficacy and safety of pharmacological interventions, namely nifedipine, sildenafil, iloprost, and bosentan in treating RP and DU in patients with SSc and other CTD. Scarce and low-quality evidence does support the use of some non-pharmacological interventions but with only a modest effect size. This SLR underscores the limited availability of high-quality evidence for determining the optimal treatment.

Reactive arthritis as a rare complication of intravesical bacillus Calmette-Guérin treatment: Report of two cases.

Intravesical bacillus Calmette-Guérin (BCG) immunotherapy is recommended for non-muscle-invasive bladder cancer after transurethral resection. BCG-associated musculoskeletal adverse events are rare. We report two cases of BCG reactive arthritis that were unusually severe and refractory. These describe two male patients who presented with polyarthritis after BCG exposure. Ultrasonography-guided glucocorticoid injections, high-dose systemic glucocorticoids and the institution of sulfasalazine were required for achievement of remission. Bacillus Calmette-Guérin reactive arthritis can present as polyarthritis of small and medium joints or as mono-oligoarthritis of asymmetrical ankles and knees, frequently associated with tenosynovitis and enthesitis. The mechanism by which BCG promotes arthralgia and arthritis is poorly understood. The most well-accepted theory is that the BCG antigens migrate to different peripheral tissues, including the joints. There is also a lack of knowledge regarding risk factors, with possible genetic factors playing a role. As the two presented cases show, BCG-induced reactive arthritis should be considered in the differential diagnosis of arthritis and refractory tenosynovitis in BCG-exposed patients.

Predictors of Interstitial Lung Disease in Mixed Connective Tissue Disease.

Interstitial lung disease (ILD) frequently complicates mixed connective tissue disease (MCTD) and contributes to increased mortality. We aimed to identify predictors of ILD in MCTD patients. This is a nationwide, multicentre, retrospective study including patients with an adult-onset MCTD clinical diagnosis who met Sharp's, Kasukawa, Alarcón-Segovia, or Kahn's diagnostic criteria and had available chest high-resolution computed tomography (HRCT) data. Univariate and multivariate analyses were conducted. We included 57 MCTD patients, with 27 (47.4%) having ILD. Among ILD patients, 48.1% were asymptomatic, 80.0% exhibited a restrictive pattern on pulmonary function tests, and 81.5% had nonspecific interstitial pneumonia on chest HRCT. Gastroesophageal involvement (40.7% vs. 16.7%, p = 0.043) and lymphadenopathy at disease onset (22.2% vs. 3.3%, p = 0.045) were associated with ILD. Binary logistic regression identified lymphadenopathy at disease onset (OR 19.65, 95% CI: 1.91-201.75, p = 0.012) and older age at diagnosis (OR 1.06/year, 95% CI: 1.00-1.12, p = 0.046) as independent ILD predictors, regardless of gender and gastroesophageal involvement. This study is the first to assess a Portuguese MCTD cohort. As previously reported, it confirmed the link between gastroesophageal involvement and ILD in MCTD patients. Additionally, it established that lymphadenopathy at disease onset and older age at diagnosis independently predict ILD in MCTD patients.

The idiopathic inflammatory myopathies module of the Rheumatic Diseases Portuguese Register.

AIMS: To characterise the idiopathic inflammatory myopathies (IIM) module of the Rheumatic Diseases Portuguese Register (Reuma.pt/myositis) and the patients in its cohort. METHODS: Reuma.pt is a web-based system with standardised patient files gathered in a registry. This was a multicentre open cohort study, including patients registered in Reuma.pt/myositis up to January 2022. RESULTS: Reuma.pt/myositis was designed to record all relevant data in clinical practice and includes disease-specific diagnosis and classification criteria, clinical manifestations, immunological data, and disease activity scores. Two hundred eighty patients were included, 71.4% female, 89.4% Caucasian, with a median age at diagnosis and disease duration of 48.9 (33.6-59.3) and 5.3 (3.0-9.8) years. Patients were classified as having definite (N=57/118, 48.3%), likely (N=23/118, 19.5%), or possible (N=2/118, 1.7%) IIM by 2017 EULAR/ACR criteria. The most common disease subtypes were dermatomyositis (DM, N=122/280, 43.6%), polymyositis (N=59/280, 21.1%), and myositis in overlap syndromes (N=41/280, 14.6%). The most common symptoms were proximal muscle weakness (N=180/215, 83.7%) and arthralgia (N=127/249, 52.9%), and the most common clinical signs were Gottron's sign (N=75/184, 40.8%) and heliotrope rash (N=101/252, 40.1%). Organ involvement included lung (N=78/230, 33.9%) and heart (N=11/229, 4.8%) involvements. Most patients expressed myositis-specific (MSA, N=158/242, 65.3%) or myositis-associated (MAA, 112/242, 46.3%) antibodies. The most frequent were anti-SSA/SSB (N=70/231, 30.3%), anti-Jo1 (N=56/236, 23.7%), and anti-Mi2 (N=31/212, 14.6%). Most patients had a myopathic pattern on electromyogram (N=101/138, 73.2%), muscle oedema in magnetic resonance (N=33/62, 53.2%), and high CK (N=154/200, 55.0%) and aldolase levels (N=74/135, 54.8%). Cancer was found in 11/127 patients (8.7%), most commonly breast cancer (N=3/11, 27.3%). Most patients with cancer-associated myositis had DM (N=8/11, 72.7%) and expressed MSA (N=6/11) and/or MAA (N=3/11). The most used drugs were glucocorticoids (N=201/280, 71.8%), methotrexate (N=117/280, 41.8%), hydroxychloroquine (N=87/280, 31.1%), azathioprine (N=85/280, 30.4%), and mycophenolate mofetil (N=56/280, 20.0%). At the last follow-up, there was a median MMT8 of 150 (142-150), modified DAS skin of 0 (0-1), global VAS of 10 (0-50) mm, and HAQ of 0.125 (0.000-1.125). CONCLUSIONS: Reuma.pt/myositis adequately captures the main features of inflammatory myopathies' patients, depicting, in this first report, a heterogeneous population with frequent muscle, joint, skin, and lung involvements.

The Mediterranean diet, and not dietary inflammatory index, is associated with rheumatoid arthritis disease activity, the impact of disease and functional disability.

PURPOSE: To assess the relationship between adherence to the Mediterranean Diet (MD) /individual Dietary Inflammatory Index (DII) and disease activity, disease impact, and functional status in Rheumatoid Arthritis (RA) patients. METHODS: RA patients followed at a hospital in Lisbon, Portugal, were recruited. DII was calculated using dietary intake data collected with a food frequency questionnaire (FFQ). Adherence to the MD was obtained using the 14-item Mediterranean Diet assessment tool. Disease Activity Score of 28 Joints (DAS28) and the DAS28 calculated with C-Reactive Protein (DAS28-CRP) were used to assess disease activity. Impact of disease and functional status were evaluated using the Rheumatoid Arthritis Impact of Disease (RAID) questionnaire and the Health Assessment Questionnaire (HAQ), respectively. RESULTS: 120 patients (73.3% female, 61.8 ± 10.1 years of age) were included. Patients with higher adherence to the MD had significantly lower DAS28-CRP (median 3.27(2.37) vs 2.77(1.49), p = 0.030), RAID (median 5.65(2.38) vs 3.51(4.51), p = 0.032) and HAQ (median 1.00(0.56) vs 0.56(1.03), p = 0.013) scores. Higher adherence to the MD reduced the odds of having a higher DAS28 by 70% (OR = 0.303, 95%CI = (0.261, 0.347), p = 0.003). Lower adherence to MD was associated with higher DAS28-CRP (ß = - 0.164, p = 0.001), higher RAID (ß = - 0.311, p < 0.0001), and higher HAQ scores (ß = - 0.089, p = 0.001), irrespective of age, gender, BMI and pharmacological therapy. Mean DII of our cohort was not significantly different from the Portuguese population (0.00 ± 0.17 vs - 0.10 ± 1.46, p = 0.578). No associations between macronutrient intake or DII and RA outcomes were found. CONCLUSIONS: Higher adherence to the MD was associated with lower disease activity, lower impact of disease, and lower functional disability in RA patients.

Myositis Multidisciplinary Clinic in a Tertiary Referral Center.

Background: Idiopathic inflammatory myopathies (IIM) are a rare heterogeneous group of diseases characterised by chronic skeletal muscle inflammation, but other organs are also frequently involved. IMM represent a diagnostic challenge and a multidisciplinary approach is important to ensure successful diagnosis and adequate follow-up of these patients. Objective: To describe the general functioning of our multidisciplinary myositis clinic, highlighting the benefits of multidisciplinary team management in patients with confirmed or suspected IIM and to characterise our clinical experience. Methods: Description of the organization of a dedicated multidisciplinary myositis outpatient clinic, supported by IMM specific electronic assessment tools and protocols based on our Portuguese Register - Reuma.pt. In addition, an overview of our activity between 2017 and 2022 is provided. Results: An IIM multidisciplinary care clinic, based on a close collaboration between Rheumatologists, Dermatologists and Physiatrist is detailed in this paper. One hundred and eighty-five patients were assessed in our myositis clinic; 138 (75%) of those were female, with a median age of 58 [45-70] years. At the last appointment, 130 patients had a confirmed IIM diagnosis, and the mean disease duration was 4 [2-6] years. The most frequent diagnosis was dermatomyositis (n = 34, 26.2%), followed by antisynthetase syndrome (n = 27, 20.8%) and clinically amyopathic/paucimyopathic dermatomyositis (n = 18, 13.8%). Twenty-four patients (18.5%) were on monotherapy and 94 (72.3%) were on combination therapy. Conclusion: A multidisciplinary approach is important to ensure the correct diagnosis and follow-up of these patients. A myositis clinic, with a standardised practice at a tertiary hospital level, contributes to a standardization of care and opens research opportunities.

Safety of intra-articular glucocorticoid injections - state of the art.

Intra-articular glucocorticoid injection (IAGCI) is frequently used to treat joint pain and inflammation. While its efficacy has been extensively studied, there are not as many detailed descriptions regarding safety. This review aimed to describe the immediate-, short- and long-term complications of IAGCI and their predictors. Most studies mainly report mild and self-limited adverse events with an incidence similar to placebo. However, the reported incidences vary significantly and are mostly inferred from retrospective data. Septic arthritis is the most feared adverse event due to its association with high mortality. Other short-term local complications include injection site pain, post-injection flare, skin hypopigmentation and atrophy, and tendon rupture. Systemic side effects are common, including vasovagal reactions, flushing, increased appetite and mood changes, hyperglycemia in diabetic patients, and bleeding in high-risk patients. Few predictors of complications have been systematically evaluated. However, male gender, advanced age, and pre-existing joint disease have been suggested in retrospective studies to correlate with infection risk. Overall, in most studies, only severe adverse event rates are reported, with no systematic prospective evaluations of safety and no report of predictors of complications. Therefore, since IAGCI is a routinely used treatment, more detailed knowledge of adverse events and complications is warranted.

Predictors of cardiac involvement in idiopathic inflammatory myopathies.

Objectives: Idiopathic inflammatory myopathies (IIM) are a group of rare disorders that can affect the heart. This work aimed to find predictors of cardiac involvement in IIM. Methods: Multicenter, open cohort study, including patients registered in the IIM module of the Rheumatic Diseases Portuguese Register (Reuma.pt/Myositis) until January 2022. Patients without cardiac involvement information were excluded. Myo(peri)carditis, dilated cardiomyopathy, conduction abnormalities, and/or premature coronary artery disease were considered. Results: 230 patients were included, 163 (70.9%) of whom were females. Thirteen patients (5.7%) had cardiac involvement. Compared with IIM patients without cardiac involvement, these patients had a lower bilateral manual muscle testing score (MMT) at the peak of muscle weakness [108.0 ± 55.0 vs 147.5 ± 22.0, p=0.008] and more frequently had oesophageal [6/12 (50.0%) vs 33/207 (15.9%), p=0.009] and lung [10/13 (76.9%) vs 68/216 (31.5%), p=0.001] involvements. Anti-SRP antibodies were more commonly identified in patients with cardiac involvement [3/11 (27.3%) vs 9/174 (5.2%), p=0.026]. In the multivariate analysis, positivity for anti-SRP antibodies (OR 104.3, 95% CI: 2.5-4277.8, p=0.014) was a predictor of cardiac involvement, regardless of sex, ethnicity, age at diagnosis, and lung involvement. Sensitivity analysis confirmed these results. Conclusion: Anti-SRP antibodies were predictors of cardiac involvement in our cohort of IIM patients, irrespective of demographical characteristics and lung involvement. We suggest considering frequent screening for heart involvement in anti-SRP-positive IIM patients.

Idiopathic inflammatory myopathies: one year in review 2022.

Idiopathic inflammatory myopathies (IIM) are a heterogeneous group of disorders in which chronic inflammation of the skeletal muscle, leading to muscle weakness, is a common feature. Different phenotypes have been identified within the IIM spectrum based on extra-muscular manifestations, immunology, muscle histology, responsiveness to therapy, and prognosis. The pathogenesis, classification, treatment, and prognosis of the different IIM subtypes are subject to active discussion and research. This review highlights the most relevant literature published on this topic over the last year.

Clinical characterisation of a multicentre nationwide cohort of patients with antisynthetase syndrome.

BACKGROUND: Antisynthetase syndrome (ASyS) is characterised by the association of inflammatory myopathy, interstitial lung disease (ILD), arthritis, Raynaud's phenomenon (RP) or mechanic's hands (MH), with the presence of anti-aminoacyl-tRNA-synthetase antibodies (anti-ARS). It has been suggested that different anti-ARS may be associated with distinct clinical pictures. OBJECTIVE: To characterise the clinical and immunological features of a multicentric nationwide cohort of ASyS patients. METHODS: This is a multicentre retrospective cohort study including patients with ASyS from nine Portuguese rheumatology centres. Data on patients' demographics, signs and symptoms, laboratory results, pulmonary imaging findings and treatment with immunomodulators were collected. Comparison between patients with different anti-ARS antibodies was made using the Chi-square test for categorical variables and Student's t-test or Man-Whitney test for continuous variables, considering anti-Jo1 positive patients as the reference group. RESULTS: Seventy patients were included (70% female) with a median age in years at disease onset of 52 (15-75) years and median follow-up time of 3 years (range 0-32). The three most common clinical manifestations were ILD (n=53, 75.7%), followed by arthritis (n=43, 61.4%) and myositis (n=37, 52.9%). Forty-three patients were positive for anti-Jo1 (61.4%), 11 for anti-PL12 (15.7%), 10 for anti-PL7 (14.3%), 4 for anti-EJ (5.7%), and 2 for anti-OJ (2.9%) antibodies. Antibody co-positivity with anti-Ro52 antibodies was found in 15 patients (21.4%) and was more prevalent in anti-Jo1 patients. ILD prevalence was similar in the different anti-ARS subgroups, without statistically significant differences. Patients positive for anti-PL7 antibodies had significantly lower risk of presenting arthritis (p =< 0.05) and those positive for anti-PL-12 antibodies had a significantly lower risk of presenting myositis than the reference group of anti-Jo1 positive patients (p =< 0.05). RP was more frequently found in patients positive for anti-PL-12 than in anti-Jo1-positive patients (p =< 0.05). Malignancies were reported in four (5.7%) patients, none of whom were anti-Ro52-positive, and one of such patients had a double malignancy. Only three deaths were reported. Corticosteroids were the most frequently prescribed therapy and the use of immunosuppressive drugs was decided according to the type of predominant clinical manifestation. CONCLUSION: The three most common clinical manifestations were ILD, followed by arthritis and myositis. Patients positive for anti-PL7 antibodies had significantly lower risk of presenting arthritis and those positive for anti-PL-12 antibodies had a significantly lower risk of presenting myositis than the reference group of anti-Jo1 positive patients. RP was more frequently found in patients positive for anti-PL-12 than in anti-Jo1-positive patients. Corticosteroids were the most frequently prescribed therapy. These results are generally concordant with data retrieved from international cohorts.

The safety and persistence of intravenous iloprost in systemic sclerosis.

INTRODUCTION: Vasculopathy is a crucial feature of systemic sclerosis (SSc). It occurs in almost every patient with SSc, with Raynaud's phenomenon (RP) and digital ulcers (DU) having a great impact on the quality of patients' lives. Intravenous (IV) iloprost, a synthetic analogue of prostacyclin, is broadly used to treat RP and DU secondary to SSc. Currently, there is no standard protocol defined for the iloprost treatment of SSc-associated RP and DU, and, consequently, the management of this treatment is largely based on each centre's experience. OBJECTIVE: The objective of this study is to evaluate the safety profile of a particular scheme of IV iloprost used in our centre as the standard treatment of SSc-related vascular complications. METHODS: We retrospectively evaluated the clinical records of SSc patients, classified according to the 2013 European Alliance of Associations for Rheumatology (EULAR) criteria (31) with SSc-related DU and/or severe RP not responsive to CCB, receiving or who have received IV iloprost infusions from January 1st 2011 to March 31st 2021 Results: Within this time frame, 60 patients (n=44 for DU; n=16 for severe RP) were treated with a monthly 10-hour IV iloprost perfusion with a dosing regimen adapted to individual tolerance. Forty-nine of these 60 patients (81.7%) were on iloprost for more than one year. Within 12 months of therapy, 40 patients have healed the DUs (90.9%), with only 4 patients maintaining active DUs. A significant clinical improvement in RP at 12 months was observed in 87.5% (n=14/16) of SSc patients with severe RP. Eleven AE implying treatment dose/frequency adjustments or suspension were recorded (18.3% of patients): severe headache (n=5), hypotension (n=3), tachycardia (n=1), flushing (n=1) and generalised erythroderma (n=1). In all patients, the perfusion rate was reduced in the following treatment sessions with good tolerance, with the exception of the patient with the generalised erythroderma reaction, who suspended the perfusion and was later switched to bosentan. After a mean follow-up time of 6.9 (+/-) 4.0 years of treatment (range 0.06-22), 24 patients (40%) stopped the therapy, 14 (58.3%) of whom due to clinical improvement. The overall 5-, and 10-year survival rates of IV iloprost were 68.2% and 55.6%, respectively. CONCLUSION: SSc patients who received this flexible IV iloprost regimen achieved clinical improvement, reflected in the high persistence rate of the drug, with a good tolerability profile. In addition, most side effects were mild and easily managed.