Standardized nailfold capillaroscopy in children with rheumatic diseases: a worldwide study.

OBJECTIVES: To standardly assess and describe nailfold videocapillaroscopy (NVC) assessment in children and adolescents with juvenile rheumatic and musculoskeletal diseases (jRMD) vs healthy controls (HCs). MATERIAL AND METHODS: In consecutive jRMD children and matched HCs from 13 centres worldwide, 16 NVC images per patient were acquired locally and read centrally per international consensus standard evaluation of the EULAR Study Group on Microcirculation in Rheumatic Diseases. A total of 95 patients with JIA, 22 with JDM, 20 with childhood-onset SLE (cSLE), 13 with juvenile SSc (jSSc), 21 with localized scleroderma (lSc), 18 with MCTD and 20 with primary RP (PRP) were included. NVC differences between juvenile subgroups and HCs were calculated through multivariable regression analysis. RESULTS: A total of 6474 images were assessed from 413 subjects (mean age 12.1 years, 70.9% female). The quantitative NVC characteristics were significantly lower or higher in the following subgroups compared with HCs: for density: lower in jSSc, JDM, MCTD, cSLE and lSc; for dilations: higher in jSSc, MCTD and JDM; for abnormal shapes: higher in JDM and MCTD; for haemorrhages: higher in jSSc, MCTD, JDM and cSLE. The qualitative NVC assessment of JIA, lSc and PRP did not differ from HCs, whereas the cSLE and jSSc, MCTD, JDM and cSLE subgroups showed more non-specific and scleroderma patterns, respectively. CONCLUSIONS: This analysis resulted from a pioneering registry of NVC in jRMD. The NVC assessment in jRMD differed significantly from HCs. Future prospective follow-up will further elucidate the role of NVC in jRMD.

Nailfold capillaroscopy in SSc: innocent bystander or promising biomarker for novel severe organ involvement/progression?

OBJECTIVES: Nailfold videocapillaroscopy (NVC) plays a well-established role in differentiating primary from secondary RP due to SSc. However, the association of NVC with novel severe organ involvement/progression in SSc has never been evaluated in a multicentre, multinational study, which we now perform for the first time. METHODS: Follow-up data from 334 SSc patients [265 women; 18 limited SSc (lSSc)/203 lcSSc/113 dcSSc] registered between November 2008 and January 2016 by seven tertiary centres in the EUSTAR-database, were analysed. Novel severe organ involvement/progression was defined as new/progressive involvement of the peripheral vasculature, lungs, heart, skin, gastrointestinal tract, kidneys, musculoskeletal system, or death, at the 12- or 24-month follow-up. NVC images at enrolment were quantitatively and qualitatively evaluated according to the standardized definitions of the EULAR Study Group on Microcirculation in Rheumatic Diseases. Uni- and multivariable logistic regression modelling (ULR, MLR) was performed. RESULTS: Of the 334 included SSc patients, 257 (76.9%) developed novel overall severe organ involvement/progression. Following MLR, normal capillary density was associated with less-frequent novel overall severe organ involvement/progression [odds ratio (OR) = 0.77, P < 0.001] and novel peripheral vascular involvement (OR = 0.79, P = 0.043); microhaemorrhages were associated with less novel pulmonary hypertension (OR = 0.47, P = 0.029); and a 'severe' (active/late) NVC pattern was associated with novel overall severe organ involvement/progression (OR = 2.14, P = 0.002) and skin progression (OR = 1.70, P = 0.049). CONCLUSIONS: Our results suggest that NVC may be a promising biomarker in SSc, certainly warranting further investigation. Despite the participation of tertiary centres, which follow their patients in a standardized way, we were underpowered to detect associations with infrequent severe organ involvement/progression.

High frequency ultrasonography: reliable tool to measure skin fibrosis in SSC? A systematic literature review and additional pilot study.

OBJECTIVES: To investigate the reliability of high frequency ultrasound (HFUS) in measuring skin fibrosis in SSc. METHODS: First, a systematic review (according to PRISMA) was conducted to identify studies that documented HFUS' reliability in SSc as a primary outcome. Then, in an additional pilot study, the inter- and intra-rater reliability of two investigators performing HFUS for dermal thickness (DT) measurements in a standardized manner across all 17 areas of the modified Rodnan Skin Score was evaluated in a group of 59 SSc patients and descriptively in 44 healthy controls (HC). As an external validation, DT measurements by HFUS were performed in a separate group of 30 SSc patients by the same first and another third investigator. RESULTS: The systematic review retained few (4/1719 unique records) small-scale studies, with mixed study populations (combining SSc and HC). The reported data herein are suggestive of the inter-/intra-rater reliability of HFUS (intra-class correlation coefficient [ICCs] ranging 0.65-0.94/0.55-0.96, respectively). Additionally, in our pilot study, inter-/intra-rater reliability was good-to-excellent in both SSc groups and HC (ICCs ranging 0.70-0.97/0.70-0.98 and 0.65-0.95/0.63-0.96, respectively). CONCLUSION: The identified small-scale studies were not only combining data from SSc and HC, they were also heterogeneous in terms of technical aspects (probes and frequency), image acquisition methods ([number of] areas assessed) and definitions used for skin thickness, which prevents drawing unequivocal conclusions. Despite these limitations, our standardized pilot study corroborated the findings in literature, paving the way for the applicability of HFUS as a reliable (complementary) tool to quantify skin fibrosis in SSc.

Reliable detection of subtypes of nailfold capillary haemorrhages in childhood-onset systemic lupus erythematosus.

OBJECTIVES: In systemic lupus erythematosus (SLE), it is necessary to obtain biomarkers that predict cardiovascular complications due to premature atherosclerosis, which is related to endothelial dysfunction. Nailfold capillary abnormalities might be a biomarker for endothelial dysfunction. In adults and children with SLE, nailfold capillary haemorrhages have shown to be significantly correlated with disease activity. Recently, different subtypes of capillary haemorrhages have been described in childhood-onset SLE (cSLE). The aim of the current study was to assess the inter- and intra-rater reliability of observations of different subtypes of haemorrhages in cSLE patients. METHODS: Five raters blindly evaluated 140 capillaroscopy images from 35 cSLE-patients (diagnosed according to the 2012 SLICC criteria). The images were assessed qualitatively (present or absent) and quantitatively (total number) on four different subtypes of haemorrhages: 1) punctate extravasations, 2) perivascular haemorrhage, 3) large confluent haemorrhage and 4) non-definable. As subgroups 1) and 2) were interpreted as a continuous spectrum, a post-hoc analysis with "merged" (mean) kappa/ICC was additionally calculated as one sub-group. RESULTS: Qualitative assessment showed a kappa 0.65 (95% CI: 0.60-0.70) for "punctate extravasations and perivascular haemorrhages merged" and a kappa 0.78 (95% CI: 0.72-0.83) for large confluent haemorrhages. For the quantitative assessment, ICC was 0.82 (95% CI: 0.76-0.87) for the "merged groups" and ICC 0.93 (95% CI: 0.91-0.95) for large confluent haemorrhages. CONCLUSIONS: Our study shows that different subtypes of capillary haemorrhages in cSLE-patients could be reliably reproduced by different raters. This confirms our recent observation of perivascular extravasations as a subgroup of capillary haemorrhage in cSLE that might reflect endothelial dysregulation.

Nailfold capillaroscopy in Sjögren's syndrome: a systematic literature review and standardised interpretation.

OBJECTIVES: To identify the role of nailfold capillaroscopy (NC) in Sjögren's syndrome (SS). METHODS: The literature was systematically reviewed in three databases. All published original studies which assess patients with SS by NC were revised. A quality assessment was applied to all studies based on population description, presence of a control group, presence of instrumental specifications and/or standardly applied NC methodology, presence of clear descriptions of capillaroscopic characteristics and based on the used statistical analysis. The capillaroscopic findings per study were described in a EULAR consented standardised way. Significant associations of capillaroscopic characteristics in SS patients with clinical and laboratory variables were summarised. RESULTS: The search resulted in 869 hits. Based on title and abstract screening 29 original studies were identified and of these, 14 full texts described an assessment by NC in SS. Seven studies were retained after performing a critical quality assessment. One study compared NC in SS with healthy controls and attested a lower capillary density in SS. Concerning clinical associations, capillary density was associated with Raynaud's phenomenon in two studies and with interstitial lung disease or systemic manifestations in one study each. No association between serologic features (anti-nuclear antibodies, anti-SSA, anti-SSB and anti-RF) and NC characteristics were found. CONCLUSIONS: A small number of studies have investigated the role of NC in SS. More studies, including prospective follow up studies with standard NC evaluation in SS are needed.

Capillaroscopy in childhood-onset systemic lupus erythematosus: a first systematic review.

OBJECTIVES: Recently, a systematic review indicated that, compared to healthy controls, adult patients with systemic lupus erythematosus (SLE) show a significantly more abnormal capillary morphology and greater number of haemorrhages in nailfold capillaroscopy and that these capillary changes are associated with disease activity. As yet, no systematic literature evaluation of capillaroscopy in childhood-onset SLE (cSLE) has been performed. Therefore, we aimed to systematically review the literature on nailfold capillary characteristics in cSLE. METHODS: Search terms "SLE or Lupus", "Capillaroscopy" and "Juvenile or Childhood or Paediatric or Child" were used in PubMed, Embase and Web of Science. Capillary findings were evaluated according to the current international consensus-based definitions for analysis of capillaroscopic characteristics from the European League against Rheumatism (EULAR) Study Group on Microcirculation in Rheumatic Diseases (SG MC/RD). RESULTS: After screening eighty search hits, six articles were retained, two of which were case-control studies and four case series. For capillary density, no difference was found between cSLE and healthy controls (one study). Differences in capillary diameter, capillary morphology, haemorrhages and semi-quantitative score were inconclusive or non-interpretable. A scleroderma pattern was not detected in the case control studies but was reported in a minority of cSLE patients in 3 out of 4 case series. CONCLUSIONS: Literature on nailfold capillary findings in cSLE is scarce and inconclusive. To evaluate capillary characteristics in cSLE, prospective longitudinal studies are needed. Future studies should use uniform definitions for capillary characteristics and findings should be compared with healthy controls, matched for age and ethnicity. The EULAR SG MC/RD is stepping up to this need.

Automated assessment of absolute nailfold capillary number on videocapillaroscopic images: Proof of principle and validation in systemic sclerosis.

BACKGROUND: Absolute nailfold capillary number should be a putative biomarker in selected rheumatic diseases but could be time-consuming and not highly repeatable. OBJECTIVE: To validate an automated software for absolute nailfold capillary number and density evaluation, on NVC images in SSc. METHODS: An automated software to count nailfold capillary number (AUTOCAPI) had been constructed, through an exploratory image set. Subsequently, application rules have been created to define the ROI in NVC images, through a training images set. The software reliability was assessed through calculation of the ICC between automatic and manual counting, by four independent observers, on the same NVC images. RESULTS: The following ICC's were obtained per observer, for the patients with SSc (40 images), the healthy (20 images), and the PRP subgroups (20 images), respectively: 0.94, 0.81, and 0.62 (observer 1); 0.94, 0.91, and 0.67 (observer 2); 0.88, 0.56, and 0.64 (observer 3); and 0.88, 0.85, and 0.85 (observer 4). CONCLUSIONS: The validation of an automated software for measuring absolute nailfold capillary number and density in SSc was achieved. The integration into the pre-existing imaging software should make the assessment of the capillary number in NVC easier, quicker, and standardized.

A prospective, longitudinal study evaluating the baseline six-minute walk test as an individual reference value in systemic sclerosis patients.

OBJECTIVES: Interstitial lung disease (ILD) and pulmonary arterial hypertension (PAH) are the leading causes of death in systemic sclerosis (SSc). Although the six-minute walk test (6MWT) is used for evaluating ILD and PAH, no data are available on the evolution of the six-minute walk distance (6MWD) in SSc patients without ILD and PAH and whether the baseline 6MWD could serve as individual reference value for the management of those who will develop PAH or ILD. METHODS: Prospectively collected data of the first 6MWT (at baseline or 6-month follow-up) and the 6MWTs at 18-, 30-, 42-, 54-, and 66-month visit of 165 consecutive SSc patients without ILD and PAH, included in the Ghent University SSc Cohort between May 2006 and December 2016 were analysed. RESULTS: 96-100% of the included patients performed a 6MWT during the follow-up visits. The mean 6MWD during the baseline 6MWT of 165 SSc patients without ILD and PAH (35% limited, 56% limited cutaneous, 9% diffuse cutaneous SSc) was 484.20+/-92.65m with no significant difference in the 6MWD at different follow-up visits as compared to baseline. In 46 SSc patients without ILD and PAH who performed a 6MWT at baseline and at 66-month visit, the 6MWD walked at 66-month visit correlated with the baseline 6MWD (r=0.564, p<0.001). CONCLUSIONS: In SSc without ILD and PAH, the 6MWT is feasible and the 6MWD is clinically stable over a 66 months period. Hence, the individual 6MWD might be used as individual reference value in management of those who will develop PAH or ILD.

Screening for pulmonary arterial hypertension in an unselected prospective systemic sclerosis cohort.

Screening for pulmonary arterial hypertension (PAH) in systemic sclerosis (SSc) improves outcomes. The DETECT screening algorithm is recommended in a high-risk SSc subgroup. This study aims to compare prospectively the positive predictive value of screening using the DETECT algorithm and the 2009 European Society of Cardiology/European Respiratory Society (ESC/ERS) guidelines, and to compare their cost-effectiveness in an unselected, day-to-day SSc population. Post hoc, screening according to the 2015 ESC/ERS guidelines using echocardiographic parameters alone ("2015 echo screening") or combined with the DETECT algorithm ("2015 combined screening") in high-risk subjects was analysed.195 consecutive SSc patients included in the Ghent University Hospital SSc cohort were screened using different algorithms.The referral rate for right heart catheterisation was 32% (63 out of 195 patients) (46/4/13/34/40 patients using the DETECT algorithm/2009 guidelines/both/2015 echo screening/2015 combined screening). Right heart catheterisation was performed in 53 patients (84%) (36 (78%)/four (100%)/13 (100%)/28 (82%)/32 (80%) patients recommended by the DETECT algorithm/2009 guidelines/both/2015 echo screening/2015 combined screening). PAH was diagnosed in three patients (incidence 1.5%·year-1, 95% CI 0.5-4.4), in whom all algorithms recommended a right heart catheterisation. The positive predictive value was 6% (95% CI 2-17%; three out of 49 patients) for the DETECT algorithm, 18% (95% CI 6-41%; three out of 17 patients) for the 2009 guidelines, 23% (95% CI 8-50%; three out of 13 patients) for both, 11% (95% CI 4-27%; three out of 28 patients) for the 2015 echo screening and 9% (95% CI 3-24%; three out of 32 patients) for the 2015 combined screening. The cost was EUR224/80/90/112 per patient using the DETECT algorithm/2009 guidelines/2015 echo screening/2015 combined screening.Echocardiography may remain a candidate first step for PAH screening in SSc.

Six-minute walk test in or out in evaluation of systemic sclerosis patients?

OBJECTIVES: Interstitial lung disease (ILD) and pulmonary arterial hypertension (PAH) are the leading causes of death in systemic sclerosis (SSc) patients. Although the six-minute walk test (6MWT) is used for evaluating ILD and PAH in clinical practice, no data are available on six-minute walk distance (6MWD) and oxygen desaturation in SSc patients without ILD and PAH. METHODS: Prospectively collected data of the 6MWTs at baseline and 6-month follow-up of 300 consecutive SSc patients, included in the Ghent University Hospital Systemic Sclerosis Unit between May 2006 and April 2015 were analysed. RESULTS: The mean 6MWD of 165 SSc patients without ILD and PAH who performed a 6MWT at baseline or at the 6-month visit was 484±93m. Patients in the diffuse cutaneous (DcSSc) subgroup (435±94m) walked less than in the limited (LSSc) subgroup (499±91m, p=0.04) and tended to walk less than in the limited cutaneous (LcSSc) subgroup (483±92m, p=0.15). In 115 SSc patients without ILD and PAH who walked at both moments, there was no significant difference between the 6MWDs (mean difference -7.60m 95%CI [-19.93m; 4.73m], p=0.23) and the oxygen desaturation was not statistically different in 102 of them (mean difference 0.41% 95%CI [-0.49%; 1.31%], p=0.37). CONCLUSIONS: In SSc without ILD and PAH, the 6MWD and oxygen desaturation is clinically stable over a 6 months period. The DcSSc subgroup walks less than the LSSc and the LcSSc subgroup.

Nailfold Capillaroscopy and Clinical Applications in Systemic Sclerosis.

Capillary microscopy is a safe and non-invasive tool to evaluate the morphology of the microcirculation typically affected in SSc. Next to being paramount for the "(very) early" diagnosis of SSc eyes are also geared toward capillaroscopy with the aim to be able to use it as a biomarker, especially in the prediction of future occurrence of DU. The following review will explain what capillary microscopy is and will focus additionally on studies evaluating the association between capillaroscopy and DU.

Disease activity indices in systemic sclerosis: a systematic literature review.

OBJECTIVES: Reviewing disease activity indices (DAI) in systemic sclerosis (SSc) and reporting their validation status. METHODS: Literature was systematically reviewed on studies documenting the development of DAI, assessing the validation status of DAI and studies using a DAI in their analysis. The qualitative and quantitative validation status of existing DAI was assessed based on OMERACT and on definitions of the American College of Rheumatology (ACR) committee on quality measures. RESULTS: Three DAI in SSc have been proposed in literature: the European Scleroderma Study Group (EScSG) activity index, the 12-point DAI and the Combined Response Index for Systemic Sclerosis (CRISS). The EScSG activity index is yet applied as an outcome measure in 48 different studies. The EScSG activity index and the CRISS are provisional partially validated DAI. CONCLUSIONS: Future studies are needed to fully validate the EScSG activity index and the CRISS and to assess the validation status of the 12-point DAI.

Assessment of sensitivity to change of the European Scleroderma Study Group activity index.

OBJECTIVES: The European Scleroderma Study Group (EScSG) activity index meets nearly all the OMERACT-standards of truth, discrimination and feasibility. The sensitivity to change remains to be attested. This study assesses sensitivity to change of the EScSG activity index in patients with early and severe diffuse cutaneous Systemic Sclerosis (dcSSc) treated with rituximab. METHODS: 12-month follow-up (open-label study) of 14 consecutive patients with early dcSSc. Patients received an infusion of two times 1000 mg rituximab at month 0 and 6, together with 100 mg methylprednisolone. Clinical read outs (modified Rodnan skin score [mRSS], lung function and echocardiography) and EScSG activity index were performed at month 0, 3, 6 and 12. Mixed models analyses (MMA) were used to evaluate changes in parameters over time. RESULTS: There was a clinically significant change in skin score with a mean (SD) mRSS of 24.8 (4.44) at baseline and 10.4 (3.12) at month 12 (MMA p<0.001). Also the EScSG activity index decreased significantly, with a mean (SD) of 4.3 (1.79) at baseline and 0.7 (0.83) at month 12 (MMA p<0.001). The estimated mean change of the EScSG activity index was -3.6 (95%CI -4.9; -2.4) over 12 months. Indices of internal organ involvement remained stable throughout the study. CONCLUSIONS: A significant improvement of the EScSG activity index was observed, in line with the significant improvement of the mRSS and the stabilisation of internal organ involvement. To our knowledge, this is the first study to attest sensitivity to change of the EScSG activity index in the subset of 'early' dcSSc. TRIAL REGISTRATION: ClinicalTrials.gov Registration, http://clinicaltrials.gov, number NCT00379431.

Chronic spontaneous urticaria: Evidence of systemic microcirculatory changes.

BACKGROUND: Chronic spontaneous urticaria (CSU) is a chronic inflammatory skin disease where activation of endothelial cells (ECs) at sites of skin lesions leads to increased blood flow, leakage of fluid into the skin, cellular infiltration, and vascular remodeling. To understand the disease duration and the sometimes vague systemic symptoms accompanying flares, the objective of this study was to examine if CSU comes with systemic vascular changes at the microcirculatory level. METHODS: We investigated CSU patients (n = 49) and healthy controls (HCs, n = 44) for microcirculatory differences by nailfold videocapillaroscopy (NVC) and for blood levels of the soluble EC biomarkers serum vascular endothelial growth factor (VEGF), soluble E-selectin, and stem cell factor (SCF). Patients were also assessed for clinical characteristics, disease activity, and markers of autoimmune CSU (aiCSU). RESULTS: CSU patients had significantly lower capillary density, more capillary malformations, and more irregular capillary dilations than HCs on NVC. Serum levels of VEGF, soluble E selectin and SCF were similar in CSU patients and HCs. CSU patients with higher VEGF levels had significantly more abnormal capillaries. Patients with markers of aiCSU, that is, low IgE levels or increased anti-TPO levels, had significantly more capillaries and less capillary dilations than those without. CONCLUSION: Our results suggest that CSU comes with systemic microcirculatory changes, which may be driven, in part, by VEGF.

Incidence, prevalence and long-term progression of Goh algorithm rated interstitial lung disease in systemic sclerosis in two independent cohorts in flanders: A retrospective cohort study.

OBJECTIVES: The epidemiology of interstitial lung disease (ILD) in systemic sclerosis (SSc) in Belgium is unknown. In literature, its prevalence varies between 19% and 52% in limited/diffuse cutaneous SSc (LcSSc/DcSSc). However, its prevalence in "early" SSc (pre-clinically overt SSc without [yet] skin involvement), nor its incidence rate in SSc (LcSSc/DcSSc/"early" SSc) has ever been described. Against this background, we aimed to determine the prevalence/incidence (rate) and progression of ILD in SSc. METHODS: 12-year follow-up data of consecutive SSc patients, included in two Flemish cohorts (University Hospitals Ghent and Leuven), were retrospectively analysed. ILD was classified according to the simplified Goh algorithm. Progression of ILD was defined as a relative decline of FVC ≥10%, a combined relative decline of FVC 5-10% and DLCO ≥15%, or as an increase in HRCT extent. RESULTS: 722 patients (60% LcSSc/ 20% DcSSc/ 20% "early" SSc, median (IQR) follow-up 39 [12-80] months) had baseline HRCT. 243 were rated to have ILD at baseline and 39 during follow-up (prevalence of 34%/ incidence rate of 20.3/1000PY, 95%CI:14.5-27.8). Amongst those with baseline ILD, 60% had lung functional progression at five years of follow-up. In the "early" SSc subgroup, eight patients were rated to have ILD at baseline and three during follow-up (prevalence of 6%/ incidence rate of 5.8/1000 PY, 95%CI:1.2-17.0). CONCLUSION: Both LcSSc and DcSSc patients should be monitored for ILD evolution. The low prevalence and incidence of ILD in the "early" SSc subgroup may instruct future decisions on the construction of uniform patient follow-up pathways in "early" SSc.

Anticentromere Antibody Levels and Isotypes and the Development of Systemic Sclerosis.

OBJECTIVE: Little is known on the disease course of very early systemic sclerosis (SSc). Among the information yet to be elucidated is whether anticentromere antibody (ACA) isotype levels can serve as biomarkers for future SSc development and for organ involvement. This study was undertaken to evaluate whether IgG, IgM, and IgA ACA levels in IgG ACA-positive patients are associated with disease severity and/or progression from very early SSc to definite SSc. METHODS: IgG ACA-positive patients from 5 different cohorts who had very early SSc or SSc fulfilling the American College of Rheumatology (ACR)/European Alliance of Associations for Rheumatology (EULAR) 2013 criteria were included. A diagnosis of very early SSc was based on the presence of IgG ACAs and Raynaud's phenomenon, and/or puffy fingers and/or abnormal nailfold capillaroscopy, but not fulfilling the ACR/EULAR 2013 criteria for SSc. Multivariable regression analyses were performed to determine the association between baseline ACA isotype levels and progression to definite SSc with organ involvement. RESULTS: Six hundred twenty-five IgG ACA-positive patients were included, of whom 138 (22%) fulfilled the criteria for very early SSc and 487 (78%) had definite SSc. Levels of IgG ACAs (odds ratio 2.5 [95% confidence interval 1.8-3.7]) and IgM ACAs (odds ratio 1.8 [95% confidence interval 1.3-2.3]) were significantly higher in patients with definite SSc. Of 115 patients with very early SSc with follow-up, progression to definite SSc occurred within 5 years in 48 (42%). Progression to definite SSc was associated with higher IgG ACA levels at baseline (odds ratio 4.3 [95% confidence interval 1.7-10.7]). CONCLUSION: ACA isotype levels may serve as biomarkers to identify patients with very early SSc who are at risk for disease progression to definite SSc.

The preliminary validation of laser Doppler flowmetry in systemic sclerosis in accordance with the OMERACT filter: A systematic review.

OBJECTIVES: To investigate the validation status of laser Doppler flowmetry (LDF) in systemic sclerosis (SSc) according to the 'Outcome Measures in Rheumatologic Clinical Trials' (OMERACT) filter. METHODS: The literature was systematically reviewed to identify all reports assessing the microcirculatory flow in SSc patients. The OMERACT filter -including the domains of truth, discrimination and feasibility- was applied and a quality assessment was done by the 'Good Methods Checklist'. To ease the comparison between studies the results were grouped per dynamic test situation: basal, cold/heat challenge and occlusion. RESULTS: The literature search resulted in 4332 hits. Based on title and abstract screening 243 hits were retained and of these, 52 full texts described an assessment by LDF in SSc patients. Finally, 18 studies passed the quality assessment and form the object of this review. The review reveals that expert consensus is lacking on the face and content validity of LDF in SSc. The construct validity of LDF, on the other hand is partially validated. Conflicting results exist on the discriminant capacity of LDF in distinguishing healthy from diseased patients, primary from secondary Raynaud's phenomenon and in differentiating between disease subsets. Yet, complementing an LDF-measurement with a heat challenge, as well as the evaluation of the post-occlusive hyperaemic response, has the potential to elicit a difference between healthy and diseased patients. Lastly, data on the feasibility of LDF in SSc is lacking in the identified literature. CONCLUSION: This systematic review emphasizes the very preliminary validation status of LDF in the assessment of the microcirculatory flow in SSc.

Nailfold Videocapillaroscopy in Systemic Sclerosis-related Pulmonary Arterial Hypertension: A Systematic Literature Review.

OBJECTIVE: Pulmonary arterial hypertension (PAH) is one of the leading causes of death in systemic sclerosis (SSc). Current screening algorithms are hampered by low positive predictive values. Outcome measures that could add to performance characteristics would be welcome. We aim to evaluate the role of nailfold videocapillaroscopy (NVC) using standardized definitions, in SSc-related PAH (SSc-PAH). METHODS: A systematic review to identify original research papers documenting an association between NVC and right heart catheterization-defined SSc-PAH was performed according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines. Subsequently, NVC characteristics were subdivided into quantitative (capillary density, dimension, morphology, and hemorrhages), semiquantitative, and qualitative assessment (NVC pattern), according to the definitions of the European League Against Rheumatism Study Group on Microcirculation in Rheumatic Diseases. RESULTS: The systematic search identified 316 unique search results, of which 5 were included in the final qualitative analysis. The occurrence of incident SSc-PAH unequivocally associated in 2 longitudinal studies with progressive capillary loss (p = 0.04 and p = 0.033) and the progression to a severe (active/late) NVC pattern (p = 0.05/0.01 and HR = 5.12, 95% CI 1.23-21.27). In 3 cross-sectional studies, SSc-PAH was found to be unequivocally inversely associated with capillary density (p = 0.001 and p < 0.05) and associated with the presence of a severe NVC pattern (p = 0.03 and p < 0.05). CONCLUSION: This is the first systematic literature review investigating the role of NVC in SSc-PAH using standardized description, to our knowledge. Unequivocal associations were found between (incident) SSc-PAH and capillary density and NVC pattern. Integration of NVC into current screening algorithms to boost their performance may be a future step.