E. Praino

Prediction risk chart for scleroderma digital ulcers: A composite predictive model based on capillaroscopic, demographic and clinico-serological parameters

BACKGROUNDnDigital ulcers (DU) affect 50% of systemic sclerosis (SSc) patients, representing a challenging clinical problem. Despite a high negative predictive value, capillaroscopic scores proposed to select patients at risk for DU show an inadequate positive predictive value, especially in patients without previous DU.nnnAIM OF THIS STUDYnTo increase the predictive value for DU development of capillaroscopy, through a predictive risk chart taking into account capillaroscopic, demographic, and clinico-serological parameters.nnnPATIENTS AND METHODSnTwo hundred and nineteen unselected SSc patients from 8 Italian Rheumatology Centers were consecutively enrolled during a 6-month period. Demographic, clinical, serological and instrumental data and capillaroscopy skin ulcers risk index (CSURI) were collected.nnnRESULTSnA multivariate logistic regression analysis showed a significant positive association between DU appearance and male gender, DU history, altered CSURI, and ESR. A prediction risk chart of the development of DU within 6 months were built on the basis of the above parameters. According to the risk level, four risk classes were identified: low (≤19.3%); medium (>19.3%, ≤58.6%); high (>58.6%, ≤89.2%), and very high risk (>89.2%).nnnCONCLUSIONSnThe systematic evaluation of the above parameters can be helpful to identify patients at risk to develop DU optimizing preventive vasoactive therapy.

Nailfold Videocapillaroscopy Alterations in Dermatomyositis and Systemic Sclerosis: Toward Identification of a Specific Pattern

Objective. The term scleroderma pattern typically defines capillary abnormalities of scleroderma spectrum disorders, mainly systemic sclerosis (SSc) and dermatomyositis (DM). Our study aimed to investigate differences in nailfold videocapillaroscopy (NVC) between DM and SSc, with a cross-sectional and longitudinal evaluation. Methods. NVC features of 29 consecutive patients with DM were compared with 90 patients with SSc categorized into the 3 subsets of scleroderma pattern: early, active, and late. Twenty patients with DM and all with SSc were also longitudinally reevaluated after 30 months of followup. Results. At baseline, all SSc groups showed giant capillaries, with significant differences with DM only for early and active pattern. Ramified capillaries were significantly more frequent and severe in DM than in early and active patterns, while DM showed an opposite trend compared with late pattern. Capillary loss was lower in early pattern and higher in active and late, compared with DM. Finally, giant-ramified capillaries were almost exclusive of DM. During followup, NVC showed a different evolution in DM and SSc. In DM we recorded a reduction of giant capillaries, while ramified capillaries increased both in DM and in early and active SSc pattern. The number of capillaries recovered in DM; conversely, capillary loss slightly worsened in all SSc patterns. Giant-ramified capillaries significantly decreased in patients with DM, remaining rare in patients with SSc. Conclusion. Our study strengthens the specificity of DM and SSc microangiopathy and points out the need for large prospective studies to confirm our results and possibly to revise current terminology by distinguishing between “scleroderma” and “dermatomyositis” patterns.

Effect of treatment with iloprost with or without bosentan on nailfold videocapillaroscopic alterations in patients with systemic sclerosis

Abstract Introduction: Vascular involvement plays a decisive role in systemic sclerosis (SSc) pathogenesis; it is responsible for some important clinical manifestations of the disease such as Raynaud’s phenomenon and digital ulcers (DU). Bosentan, a dual receptor endothelin antagonist, and iloprost, often in combination therapy, seems to be able to interfere with the scleroderma microangiopathy. Objectives: Aim of the study was to evaluate the effect of bosentan and iloprost on scleroderma microangiopathy, analyzed by means of capillaroscopic skin ulcer risk index (CSURI), in SSc patients treated for the prevention of DU. Methods: Nailfold videocapillaroscopy (NVC) was performed in 95 SSc patients, treated with iloprost alone (group 1) or combination therapy with iloprost and bosentan (group 2), at baseline and after one year. In all patients CSURI was calculated according to the formula “diameteru2009×u2009number of megacapillaries/(total number of capillaries)2”: in addition, total number of capillaries, giant capillaries, micro-hemorrhages, disorganization of the vascular array, and ramified capillaries were evaluated by means of a semiquantitative score. Results: After 12 months, we observed a reduction of the number of giant capillaries in both groups, while an increase of ramified capillaries was recorded only in group 2. CSURI improved slightly in group 2 without statistical significance; on the contrary, in group 1 a significant worsening was recorded (pu2009≤u20090.001). Conclusions: Our study confirms the effectiveness of bosentan, in combination with iloprost, in SSc microangiopathy observed to NVC. Moreover, the observed findings further support the role of CSURI in the evaluation and monitoring of SSc microangiopathy.

SAT0621 Validation Study of Predictive Value of Capillaroscopic Skin Ulcer Risk Index (CSURI) in Scleroderma Patients Treated with Bosentan

Background CSURI is a capillaroscopic index, able to identify scleroderma (SSc) patients at high risk for new or non-healing digital ulcers (DU) in the next three months. CSURI has been validated, only in patients not treated with bosentan, in a large multicenter study in 2011. Objectives To evaluate the predictive value of CSURI in SSc patients assuming bosentan for the prevention of DU. Methods Seventy-six consecutive SSc patients treated with bosentan were enrolled in a multicenter study (F/M 4.4/1; mean age 56.4±13.6 years; diffuse/limited cutaneous subset 30/44). All patients undergone to NVC and CSURI was calculated according to published studies. At baseline all patients had a history of at least one DU in the last year, and 26 patients (30.3%) showed a current DU. At the time of the study 76.3% of patients were also treated with intravenous prostanoids, while no patients was assuming bosentan for pulmonary arterial hypertension. Results After 3 months from NVC 18/26 patients showed non healing ulcers and 18/76 patients developed new DU. Receiver operator characteristic curve, performed to analyze the prognostic accuracy of CSURI in regard to DU development, is reported in the figure. The area under the curve (AUC) was 0.69 (95% CI 0.57-0.79, p=0.0019) and the higher sensitivity and specificity were observed for a CSURI value of 2.5 (sensitivity 94.4; specificity 57.5; positive and negative likehood ratio 2.22 and 0.097, respectively). At the validated cut-off value of 2.96 sensitivity was 86.1%, specificity 60.0%, positive and negative likehood ratio 2.15 and 0.23, respectively, showing a lower negative predictive value. Conclusions In patients treated with bosentan, CSURI shows a lower positive predictive value if compared with SSc population observed in our previous validation study, while the negative predictive value can be considered acceptable. The cause of this different result is not evaluable by our study. SSc peripheral microangiopathy is sustained by a multifactorial process, only partially known, involving a complex cytokines and cells network. In this picture, bosentan could reduce the incidence of new DU, without significantly interfere with the parameters included in CSURI calculation. Some Authors observed a general improvement of NVC parameters in SSc patients treated with bosentan. These data are not in contrast with our study since CSURI calculation is obtained by considering the “worst” capillaroscopic image. Moreover, a longer period of observation as in the other studies should more significantly influence changes in NVC parameters. In our previous studies, CSURI showed a higher predictive value than history of DU in detecting SSc patients at risk for new lesions. Anyway in this study this role of primary prevention cannot be applicable. Moreover, a special attention could be pointed on patients with recurrent DU, regardless specific treatments. A combined approach based on clinical picture and CSURI could probably help in managing therapy of SSc patients with DU, but only prospective clinical trial could clarify the correct role of NVC in the evaluation and management of vasoactive treatments. Disclosure of Interest None declared

AB0618 A unique ultrasound pattern of adipose tissue in systemic sclerosis patients: a comparison with rheumatoid arthritis patients and healthy controls. two sides of adipose tissue involvement in systemic chronic inflammatory diseases

Background Systemic sclerosis (SSc) and rheumatoid arthritis (RA) are both chronic and systemic inflammatory diseases, involving connective tissue. The adipose tissue is acknowledged as an immune organ that secretes numerous inflammatory signals and it is supposed playing an important role in up-regulation of inflammatory status. A few data are published on altered white adipose tissue (WFT) distribution in patients (pts) with RA. None data are available about WFT distribution in SSc pts Objectives We aimed to characterize the subcutaneous adipose tissue (total (sWFT); superficial (SsWFT); inner (IsWFT)) and visceral adipose tissue (vWTF) thickness, evaluated by ultrasound (US) of abdominal adipose tissue, in SSc pts, with different body mass index classes (BMI), comparing with RA pts and healthy controls (HC). Methods 42 SSc pts, 57 RA pts and 12 HC were recruited in this study. WFT measurements were assessed, using US (7.5 MHz probe), along the xiphoumbilican line: sWFT thickness (distance between the inner edge of the skin at the outer edge of the alba line (AL)), SsWFT (lobular upper zone of sWFT), IsWFT (sWFT- SsWFT); vWFT thickness (distance between the inner edge of the AL and the peritoneal line). Results No subject enrolled had metabolic syndrome. RA pts had thicker vWFT (15.6±7.6mm) than SSc pts (10.8±5.8mm) or HC (10.1±3.8mm) (p=0.001). In particular, the upper-weigh RA pts had vWFT 88% thicker than upper-weight HC and the RA obese pts had vWFT 87% thicker than obese HC. While, the upper-weight SSc pts had vWFT 22% thicker than upper-weight HC, and the SSc obese pts had vWFT 16% thicker than obese HC. Positive correlations were found between all WFT measures and BMI in RA pts and HC (p≤0,05). In SSc pts we found lack of correlation between SsWFT and BMI (r=0.232; p=0.145). Of note, only in SSc pts we observed different US WFT patterns (fig. 1a, fig. 1b) characterized by rearrangement of normal sWFT structure (HC fig. 1c and RA pts fig. 1d). These structural rearrangements consisted in the absence of adipose lobules, replaced by hypoechoic – anechoic areas (fig.1a) (attributable to edema), or by hyperechoic lines and spots (fig.1b) (attributable to fibrotic replacement of subcutaneous abdominal fat), independently by SSc diffuse or SSc limited skin subset. Conclusions In SSc and RA the WFT is abnormal. The WFT in RA seems be altered just for dimension and distribution, in particular the vWFT is overexpressed; it might be due to vWFT hyperactivity induced by inflammatory status. In SSc, the WFT is altered in the structure of sWFT. A direct involvement of sWFT in pathologic mechanism of SSc is supposed. An edema phase and a fibrotic phase of abdominal sWFT can be hypothesized, independently by skin involvement. If these findings will be confirmed by fat histological analysis, the US of WFT might be an important tool for the clinicians to identified the earlier stage and/or the active phase (edema) of SSc, in order to support physicians in the decision making about the treatment management. Disclosure of Interest None declared

AB0250 The adipose tissue as predictive factor of disease activity in rheumatoid arthritis patients: evaluation of body fat composition by bioelectrical impedance analysis and ultrasonography

Background Adipose tissue (AT) is an endocrine organ able to secrete the “adipokine” molecules that contribute to the low-grade inflammatory state in obese subjects and to the local inflammation that affects joints and bone (1,2). High-grade inflammation, in course of RA, leads to an altered body composition (3,4), characterized by the increasing of fat mass and the decreasing of lean mass, mostly not associated to body mass index (BMI) variations (3,5). The BMI is not able to differentiate visceral (VTH) and subcutaneous (STH) fat tissue and to distinguish between muscle mass and fat mass body composition (BC) (6,7). Alternative methods proposed for assessment of visceral fat deposition, are bioelectrical impedance analysis (BIA) and ultrasonography (US). Objectives The aim of the study is to investigate if BC, assessed by BIA and US, correlates with disease activity (assessed by the Disease Activity Score using 28 joint counts – DAS28) and affects the response to the therapy (DAS 28 variation from first evaluation). Methods 87 consecutive RA patients (pts) (72 women and 15 men; aged 52.4±13.2 years; disease duration of 10.7±8.6 years), treated with DMARDs and/or biologics (bDMARDs), were recruited during their regular visit. The inclusion criteria were the 1987 American College of Rheumatology (ACR) or ACR/EULAR 2010 classification criteria. The pts underwent to anthropometric measures (BMI); abdominal US to assess STH and VTH and derived computing of peritoneal circumference (PC); and BIA to the indices of body composition (fat-free mass index (FFMI) and fat mass index (FMI). Results We observed increasing values of BMI, FMI, VTH (fig. 1) and CP with the worsening of disease activity phases, evaluated by DAS 28. In particular, pts with DAS28≥5.1 had highest BMI (30,9±2; p=0,036), FMI (11,5±1,6; p=0,05), CP (92,7±12,5 cm; p=0,035) and VTH (24,8±5,8 mm; p=0,046) than pts in less severe disease activity. By linear regression analysis the predictor of higher DAS28 is the BMI (p=0,028). As regard the drug response, the predictors of DAS 28 improvement are higher FFMI (p=0,044) and lower BMI (p=0,015), independently by bDMARDs or DMARDs treatment. A trend to higher FMI and US AT measures was observed in female with high disease activity, in particular in menopause pts. Conclusions An altered fat distribution is observed in active RA phases; in particular, the FMI increasing is attributable just to visceral AT (VTH and CP). An inflammatory hyperactivity of visceral adiposity could be supposed in RA. The body composition, in addition to BMI, seems to predict the disease activity and drug response in RA patients. The evaluation of VTH by US could be useful to not overestimate the disease activity; instead the BIA could be a useful tool to support the clinicians in a more aggressive treatment management. References Nat Clin Pract Rheumatol 2007; 3(12):716–24. J Mol Endocrinol 2009; 43(1):11–8. Mediators Inflamm 2013; 2013:710928. Arthritis Care Res (Hoboken) 2012; 64(10):1471–9. Nat Rev Rheumatol 2010; 6(8):445–51. Curr Opin Clin Nutr Metab Care 2003; 6(4):387–93. Ann Rheum Dis 2007; 66(10):1316–21. Disclosure of Interest None declared

SAT0217 Axon Reflex Vasodilatation of Digital Arteries in Systemic Sclerosis Patients, Evaluated by Laser-Doppler Fluxmetry

Background Systemic sclerosis (SSc) is a connective disease characterized by severe microvessels vasculopathy. The important role of endothelial dysfunction in SSc pathogenesis is widely demonstrated, but the SSc related autonomic nervous system impairment is controversial and rarely described. The dysregulation of axon reflex vasodilatation of fingertip microvessels in SSc has been reported in some studies, but the functional involvement of digital arteries in SSc patients had never been investigated. Objectives We aimed at evaluating the blood flux changes mediated by axon reflex response upon heating stimulus in SSc patients. Methods 87 SSc patients (SSc pt) and 22 healthy controls (HC) were recruited in this study. The SSc patients were aged 52,7±16,2 yrs, with disease duration of 8,23±7,8 yrs. The LD Flowmetry (Periflux System 5000, Perimed) with 4 LD heating probes was used to measure the skin blood flux of the middle phalanx of the 2nd, 3rd, 4th and 5th fingers of the left hand. The skin fingers flux was recorded at pre-heating period with probes temperature fixed at 34 °C (PHF) and after 5 min heating at 44 °C (IHF). Therefore, the heating test assesses the variation of digital artery flux in response to local heating stress at 44 °C. The ratio IHF/PHF evaluates the axon reflex mediated vasodilatation (ARMV). The results are expressed as average across 4 fingers at each time. The flux was expressed in perfusion unit (PU) and HC and SSc patients responses were compared by the t-student test. Statistic significance was set at p≤0,05. The data analysis was performed using IBM SPSS statistic 20. Results The ARMV was significantly reduced in SSc patients (2,2±1,4) in comparison with HC (4,8±2,7, p=0,0001). IHF was lower in SSc patients (118,6±54,3) than HC (168±78, p=0,001). Dividing the SSc pts group by the presence of pitting scars (PS), digital ulcers (DU) and digital necrosis (DN), we observed a lower IHF in SSc pts with PS (103,2±48,6) than in SSc pts without (138,1±56, p=0,003), and in SSc pts with DU (97,8±47,6) than in SSc pts without (160,27±120,1, p=0,002). Moreover, SSc pts with ND showed a lower ARMV (1,8±1) than SSc pts without (2,6±1,5, p=0,006), and a lower IHF (98,3±49,1 vs 133,2±54,5, p=0,004). The age, sex, concomitant therapy with Ca-antagonist or Bosentan or cardioaspirin did not influence the digital artery flux. Conclusions This study provided evidence that a functional impairment of DA occurs in SSc, and it worsens with increasing severity of vascular clinical manifestations. Disclosure of Interest None declared

SAT0212 Pericardial Effusion Related To Systemic Sclerosis: A Possible Contribution of The Serum Levels of Adipokines and Interleukines

Background Pericardial effusion (PE) is a common clinical manifestation in systemic sclerosis (SSc). Few data are available about its pathogenesis. The role of adipokines and interleukins produced by the adipose tissue and the immune system in PE related to SSc had never been investigated. Objectives This study aimed at evaluating the differences in serum levels of adipokines and interleukins (IL) in systemic sclerosis (SSc) patients with and without PE. Methods A total of 87 outpatients (84 female, mean age of 52,6±14,2 ys, and disease duration of 8,2±6,7 ys), who fulfilled the ACR/EULAR 2013 SSc classification criteria, were recruited in this study. The anthropometric measures, as body mass index (BMI), demographic, clinical and laboratoristic characteristics and SSc related manifestations were assessed in each patient. The presence of PE was evaluated by means of echocardiographic techniques (the presence of fluid ≥5 cc was considered pathologic). Sera levels of adiponectin, leptin, resistin, visfatin, tumor necrosis factor α (TNF-α), interferon g (INF-g), IL-2, IL-10 and IL-17 were measured in SSc patients, using Multiplex Immunoassay (Bioplex 200 System), by means of two kits (Bioplex ProTM Cytokine/Chemokine and Growth Factor Assay e Bioplex Pro Diabetes Assay). The data normality was verified using Kolmogorov-Smirnov Test; the comparisons between SSc patients groups were evaluated by Mann-Whitney U test and t-student test, where appropiate. Statistic significance was set at p≤0,05. The results are expressed as median and interquartile range (IQR) or means±1standard deviation. The data analysis were assessed using IBM SPSS statistic 20. Results 11 SSc patients had PE. The SSc patients groups (with and without PE) did not differ in age, sex and BMI. 11 SSc patients were obese (BMI≥30) (2 with PE and 9 without PE). We found significant differences between SSc patients with PE and without PE in sera levels of visfatin (1546,9 (8590,9) vs 388,8 (103); p=0,036), adiponectin (2845000 (4132900,0) vs 5272100,0 (8243600,0); p=0,027) and IL-17 (1,33 (3,5) vs 0,05 (0,56); p=0,45). Moreover higher adiponectin/leptin ratio was found in patients with PE than SSc patients without PE (569,2 (1415,3) vs 166,9 (504,9) p=0,032). The presence of interstitial lung disease, pulmonary arterial hypertension, limited or diffuse skin subset, the different nail fold videocapillaroscopy pattern and the modified Rodnan skin score did not influenced the serum levels of adipokines and IL. In the SSc patients with PE there is no differences in visfatin and adiponectin serum level and adiponectine/leptin ratio between patients that are in menopause and those who are not. Conclusions The visfatin and adiponectin could play an important role in pathogetic mechanism in pericardial effusion related to SSc. Further study are necessary to unravel a role of visfatin and adiponectin as biomarkers of SSc and a role of the adipose tissue and innate immune system in PE related to SSc pathology. Disclosure of Interest None declared

OP0050 Serum Levels of Adipokines in The Categories of Body Mass Index (BMI) in Patients with Systemic Sclerosis

Background Adipose tissue is a source of factors stimulating the pro-oxidative-antioxidant system, such as adipokines, whose functions are closely associated with metabolic abnormalities and damage by oxidative stress. There are only few reports in literature about the correlation between body mass index (BMI), serum levels of adipokines and clinical manifestations of SSc. Objectives We evaluated serum levels of adipokines (leptin, resistin, visfatin, adiponectin) and cytokines (TNFα, IFNγ, IL-2, IL-10, IL-17) in SSc and controls (HD) and their pattern according the clinical and laboratory SSc features. Methods 89 SSc pts satisfying ACR EULAR criteria (age 52 ± 14.4 years and disease duration of 8.14 ± 6.6) and 26 HD were enrolled. Serum levels of Adiponectin, Leptin, Resistin, Visfatin, TNFα, IFNγ, IL-2, IL-10, IL-17A were measured using Bio-Rad kits and Multiplex Immunoassay tool. In all participants we collected clinical and laboratory features, such as visceral involvement, BMI, WHR (Waist to Hip Ratio), index of cardiovascular risk, acute phase reactants, cholesterol, triglycerides, smoking status, comorbidity and therapy. Data were analysed using IBM-SPSS Statistics 20 software. Mann-Whitney U-test or t-Student for unpaired data or Kruskal-Wallis test or ANOVA were used for comparison between groups. Spearmans or Pearsons test were used for correlations. A p-value ≤0.05 was considered statistically significant. Results The weight of SSc and HD differed (p<0,05) which was higher in HD. Serum levels of Leptin, Resistin, Visfatin and IL-10, IL-17 were increased in SSc compared to HD (p<0.05). In SSc, TNFα serum levels were not different from HD. Leptin levels positively correlated with body weight and BMI that in turn correlated with the values of ESR, CRP, WHR, triglycerides and cholesterol serum levels. Increased levels of IL-2, IL-10, IL-17, IFNγ, Leptin and Visfatin were found in overweight/obese SSc pateints (p<0.05) in respect to HD. TNFα was significantly increased in underweight patients (p=0.03) and there was a significant difference compared with normal weight (p=0.018). TNFα levels correlated with IL-2, IL-10, IL-17 and IFNγ levels and with esophageal involvement. There were no differences in cytokine levels between groups when correlated to skin subset, disease duration (Early/Late) and different class of cardiovascular risk. In HD, no statistically significant correlation between weight, TNFα and Leptin levels was detected. Conclusions Adipokines may play a role in inflammatory and immune pathways in SSc pathogenesis. The present data suggest a role for Leptin and TNFα as new potential SSc related circulating biomarker. Categories of modified BMI (underweight and obesity) seem to be associated to a different and a significant organ involvement in SSc. In underweight subjects, the increase of TNFα may be involved in the cachectic status, thus the role of TNFα needs be confirmed in further prospective longitudinal studies investigating also its correlation with disease severity and activity. References Pehlivan Y et al. Serum leptin, resistin and TNFa levels in patients with systemic sclerosis: the role of adipokines in scleroderma, Int J of Rheum Dis 15, 374–379, 2012 Disclosure of Interest None declared

SAT0448 Micro-Vessels Hemodynamics Effects Induced by Iloprost in Systemic Sclerosis Patients Evaluated by Laser Doppler Flowmetry

Background Iloprost is a milestone in the treatment of Raynauds Phenomenon (RP). However, it has transient hemodynamic effects due to a very short half-time, thereby a treatment protocol has never been validated and the choice of the interval time between infusions is empirical. Objectives We aimed at evaluating the short and medium term effects of Iloprost on blood flux, measured by Laser Doppler (LD), in patients with RP associated to Systemic Sclerosis (SSc). Methods 22 SSc patients with RP and 21 healthy controls (HC) were recruited in this study. The SSc patients were aged 52.6±17ys with disease duration of 8,5±6ys. All patients underwent Iloprost infusions (50ng at 1.5ng/kg/min) for 3 consecutive days. No change of the baseline therapy was allowed. The LD Flowmetry (Periflux System 5000, Perimed) with 4 LD heating probes was used to measure the fingers skin blood (FSB) flux of the middle phalanx (from the 2nd to the 5th fingers of the left hand). The LD flowmetry was performed at baseline (T0), after 3 consecutive days of Iloprost treatment (T1), and then at 24h (T2) and 7 days (T3) after the last administration of Iloprost. Two experimental protocols were applied: 1) the heating test assessing the variation of FSB flux in response to local heating stress at 44°C (the ratio between induced-heating flux and pre-heating flux (IHF/PHF) evaluates the axon reflex mediated vasodilatation1); 2) the occlusion test assessing the changes of the FSB flux after a 3 min loading period at 200mmHg applied by means of air bracelets taped on the left forearm to occlude the brachial artery (the ratio between the Peak Flux (PF) and Resting Flux (RF) evaluates the nitric oxide (NO) vessels response2). The results are expressed as average across 4 fingers at each time. The comparisons between the different time points were assessed by repeated measures ANOVA and HC and SSc patients were compared by the t-student test. Results We observed a significant difference between HC and SSc patients before and after the Iloprost infusion. An impaired axon reflex vasoregulation and nitric oxide responses were found in SSc patients, with lower IHF/PHF (heating test) (p=0,003) and PF/RF (occlusive test) (p<0,000). However, we observed a prompt improvement, even though transient, of LD parameters following Iloprost infusions in SSc patients. The occlusive test (p=0.051) highlighted a decreasing trend for the recovery time (TR; the time to reach the value of RF after the pressure relief) with a -28,3% improvement at T1. As regards the post occlusion hyperemic gain flux (po-GF), a time improving was found with the best variation observed at T1; in particular, the percentage difference with respect to T0 was: 33,8% at T1, 26% at T2, -4,3% at T3. No significant differences were found between patients with and without left hand digital ulcers, and different nailfold videocapillaroscopy pattern. Conclusions The microcirculation hemodynamic changes induced by Iloprost seem to vanish within 24h after the last infusion. Although the Iloprost treatment is effective in SSc digital ulcers management, is yet necessary to define the suitable timing to obtain long-lasting benefit. References Minson, C.T.,et al. J. Appl. Physiol. 91, 1619–1626. Grattagliano V., et al. Microvascular Research 80 (2010) 221–226. Disclosure of Interest None declared