Detection of microvascular changes in systemic sclerosis and other rheumatic diseases

Brucea javanica Seed Oil Emulsion and Shengmai Injections Improve Peripheral Microcirculation in Treatment of Gastric Cancer

OBJECTIVE

To explore and verify the effect and potential mechanism of Brucea javanica Seed Oil Emulsion Injection (YDZI) and Shengmai Injection (SMI) on peripheral microcirculation dysfunction in treatment of gastric cancer (GC).

METHODS

The potential mechanisms of YDZI and SMI were explored through network pharmacology and verified by cellular and clinical experiments. Human microvascular endothelial cells (HMECs) were cultured for quantitative real-time polymerase chain reaction, Western blot analysis, and human umbilical vein endothelial cells (HUVECs) were cultured for tube formation assay. Twenty healthy volunteers and 97 patients with GC were enrolled. Patients were divided into surgical resection, surgical resection with chemotherapy, and surgical resection with chemotherapy combining YDZI and SMI groups. Forearm skin blood perfusion was measured and recorded by laser speckle contrast imaging coupled with post-occlusive reactive hyperemia. Cutaneous vascular conductance and microvascular reactivity parameters were calculated and compared across the groups.

RESULTS

After network pharmacology analysis, 4 ingredients, 82 active compounds, and 92 related genes in YDZI and SMI were screened out. β-Sitosterol, an active ingredient and intersection compound of YDZI and SMI, upregulated the expression of vascular endothelial growth factor A (VEGFA) and prostaglandin-endoperoxide synthase 2 (PTGS2, P<0.01), downregulated the expression of caspase 9 (CASP9) and estrogen receptor 1 (ESR1, P<0.01) in HMECs under oxaliplatin stimulation, and promoted tube formation through VEGFA. Chemotherapy significantly impaired the microvascular reactivity in GC patients, whereas YDZI and SMI ameliorated this injury (P<0.05 or P<0.01).

CONCLUSIONS

YDZI and SMI ameliorated peripheral microvascular reactivity in GC patients. β-Sitosterol may improve peripheral microcirculation by regulating VEGFA, PTGS2, ESR1, and CASP9.

The association of outdoor temperature and self-reported Raynaud's phenomenon severity among people with systemic sclerosis: a Scleroderma Patient-centered Intervention Network Cohort study

BACKGROUND

Raynaud's phenomenon is the earliest and most common systemic sclerosis manifestation. Episodes can be triggered by cold exposure and ambient temperature changes. Small studies have found that Raynaud's phenomenon outcomes were associated with season. We aimed to map the degree that differences in ambient temperature are associated with Raynaud's phenomenon outcomes across the temperature spectrum.

METHODS

People with Raynaud's phenomenon secondary to systemic sclerosis in the Scleroderma Patient-centered Intervention Network Cohort completed past-week Raynaud's phenomenon severity assessments (0-10 numerical rating scale) at enrolment and longitudinally at 3-month intervals. Mean daily temperature and feels like temperature, which incorporates wind chill and humidity, for the week before each assessment were extracted for each participant from a weather site close to the participant's recruiting centre via the Iowa Environmental Mesonet. We used linear mixed models with basis splines to flexibly model non-linear changes in Raynaud's phenomenon severity across the temperature spectrum. People with lived experience of systemic sclerosis contributed to the study design and interpretation.

FINDINGS

Between April 15, 2014 and Aug 1, 2023, we included data on 20 233 Raynaud's phenomenon severity assessments from 2243 participants. 1964 (88%) of 2243 participants were women, 279 (12%) were men, and 1813 (82%) were White. Mean age was 54·8 (SD 12·7) years. The maximum predicted Raynaud's phenomenon severity score was 6·8 points (95% CI 5·6-8·1), which occurred at -25°C. Severity scores decreased minimally from -15°C to 5°C (0·05-0·21 points per 5°C difference), then decreased in larger steps between 5°C and 25°C (0·37-0·54 points per 5°C difference). The minimum predicted score was at 25°C (2·6 points [95% CI 2·5-2·7]). Scores increased at temperatures above 25°C to 3·5 points (3·0-4·1) at 35°C and 5·6 points (4·5-6·8) at 40°C. Results were similar for feels like temperature.

INTERPRETATION

Raynaud's phenomenon severity is worst at very cold temperatures but also increases with very warm temperatures, presumably due to air conditioning. Clinical management and Raynaud's phenomenon intervention trial designs should consider temperature patterns.

FUNDING

Scleroderma Society of Ontario, Scleroderma Canada, Sclérodermie Québec, Scleroderma Manitoba, Scleroderma Atlantic, Scleroderma Association of BC, Scleroderma SASK, Scleroderma Australia, Scleroderma New South Wales, Scleroderma Victoria, the Canadian Institutes of Health Research, the Arthritis Society, the Lady Davis Institute for Medical Research of the Jewish General Hospital, the Jewish General Hospital Foundation, and McGill University.

Capillaroscopy in the daily clinic of the pediatric rheumatologist

In the last decade, nailfold capillaroscopy is finding its way to the daily clinic of (pediatric) rheumatologist. This review will provide the necessary knowledge for the clinician performing this easy and non-invasive examination in children. In the first part, background information on type of capillaroscopy device and standardized (internationally validated) interpretations for the different capillary variables compared to healthy pediatric controls will be provided. The second part focusses on capillary changes that are observed in Raynaud's phenomenon with follow-up recommendations. This part will also cover capillaroscopy findings in juvenile systemic sclerosis, childhood-onset systemic lupus erythematosus, juvenile dermatomyositis and -mixed connective tissue disease, as well as correlations with disease severity. Lastly, a research agenda shows the current gaps we have in knowledge in this niche of nailfold capillaroscopy in pediatric connective tissue diseases.

Consensus statement on the diagnosis and treatment of sclerosing diseases of the skin, Part 1: Localized scleroderma, systemic sclerosis and overlap syndromes

The term 'sclerosing diseases of the skin' comprises specific dermatological entities, which have fibrotic changes of the skin in common. These diseases mostly manifest in different clinical subtypes according to cutaneous and extracutaneous involvement and can sometimes be difficult to distinguish from each other. The present consensus provides an update to the 2017 European Dermatology Forum Guidelines, focusing on characteristic clinical and histopathological features, diagnostic scores and the serum autoantibodies most useful for differential diagnosis. In addition, updated strategies for the first- and advanced-line therapy of sclerosing skin diseases are addressed in detail. Part 1 of this consensus provides clinicians with an overview of the diagnosis and treatment of localized scleroderma (morphea), and systemic sclerosis including overlap syndromes.

Cardiovascular autonomic dysfunction in post-COVID-19 syndrome: a major health-care burden

Cardiovascular autonomic dysfunction (CVAD) is a malfunction of the cardiovascular system caused by deranged autonomic control of circulatory homeostasis. CVAD is an important component of post-COVID-19 syndrome, also termed long COVID, and might affect one-third of highly symptomatic patients with COVID-19. The effects of CVAD can be seen at both the whole-body level, with impairment of heart rate and blood pressure control, and in specific body regions, typically manifesting as microvascular dysfunction. Many severely affected patients with long COVID meet the diagnostic criteria for two common presentations of CVAD: postural orthostatic tachycardia syndrome and inappropriate sinus tachycardia. CVAD can also manifest as disorders associated with hypotension, such as orthostatic or postprandial hypotension, and recurrent reflex syncope. Advances in research, accelerated by the COVID-19 pandemic, have identified new potential pathophysiological mechanisms, diagnostic methods and therapeutic targets in CVAD. For clinicians who daily see patients with CVAD, knowledge of its symptomatology, detection and appropriate management is more important than ever. In this Review, we define CVAD and its major forms that are encountered in post-COVID-19 syndrome, describe possible CVAD aetiologies, and discuss how CVAD, as a component of post-COVID-19 syndrome, can be diagnosed and managed. Moreover, we outline directions for future research to discover more efficient ways to cope with this prevalent and long-lasting condition.

Anti-survival motor neuron complex antibodies as a novel biomarker for pulmonary arterial hypertension and interstitial lung disease in mixed connective tissue disease

OBJECTIVE

The presence of anti-U1 RNP antibodies (Abs) is critical for diagnosing MCTD. The aim of this study is to evaluate the clinical relevance of anti-survival motor neuron (SMN) complex Abs, which often coexist with anti-U1 RNP Abs.

METHODS

A total of 158 newly diagnosed consecutive cases of SLE, SSc or MCTD with anti-U1 RNP Abs were enrolled in this multicentre observational study between April 2014 and August 2022. Serum anti-SMN complex Abs were screened by immunoprecipitation of 35S-methionine-labelled cell extracts, and associations between anti-SMN complex Abs positivity and clinical characteristics were analysed.

RESULTS

Anti-SMN complex Abs were detected in 36% of MCTD patients, which was significantly higher than that in SLE (8%) or SSc (12%). Among MCTD patients classified based on the combination of the clinical features of SLE, SSc and idiopathic inflammatory myopathies, anti-SMN complex Abs showed the highest prevalence in a subset with clinical features of all three components. Anti-SMN complex Abs-positive MCTD had a higher prevalence of pulmonary arterial hypertension (PAH) and interstitial lung disease (ILD), which are related to poor prognosis, than negative patients. Moreover, all three cases of death within 1 year of the treatment were positive for anti-SMN complex Abs.

CONCLUSIONS

Anti-SMN complex Abs is the first biomarker of a typical subset of MCTD which bears organ damages such as PAH and ILD.

Nintedanib downregulates the profibrotic M2 phenotype in cultured monocyte-derived macrophages obtained from systemic sclerosis patients affected by interstitial lung disease

BACKGROUND

Systemic sclerosis (SSc) is an autoimmune connective tissue disease characterized by vasculopathy and progressive fibrosis of skin and several internal organs, including lungs. Macrophages are the main cells involved in the immune-inflammatory damage of skin and lungs, and alternatively activated (M2) macrophages seem to have a profibrotic role through the release of profibrotic cytokines (IL10) and growth factors (TGFβ1). Nintedanib is a tyrosine kinase inhibitor targeting several fibrotic mediators and it is approved for the treatment of SSc-related interstitial lung disease (ILD). The study aimed to evaluate the effect of nintedanib in downregulating the profibrotic M2 phenotype in cultured monocyte-derived macrophages (MDMs) obtained from SSc-ILD patients.

METHODS

Fourteen SSc patients, fulfilling the 2013 ACR/EULAR criteria for SSc, 10 SSc patients affected by ILD (SSc-ILD pts), 4 SSc patients non affected by ILD (SSc pts no-ILD), and 5 voluntary healthy subjects (HSs), were recruited at the Division of Clinical Rheumatology-University of Genova, after obtaining Ethical Committee approval and patients' informed consent. Monocytes were isolated from peripheral blood, differentiated into MDMs, and then maintained in growth medium without any treatment (untreated cells), or treated with nintedanib (0.1 and 1µM) for 3, 16, and 24 h. Gene expression of macrophage scavenger receptors (CD204, CD163), mannose receptor-1 (CD206), Mer tyrosine kinase (MerTK), identifying M2 macrophages, together with TGFβ1 and IL10, were evaluated by quantitative real-time polymerase chain reaction. Protein synthesis was investigated by Western blotting and the level of active TGFβ1 was evaluated by ELISA. Statistical analysis was carried out using non-parametric Wilcoxon test.

RESULTS

Cultured untreated SSc-ILD MDMs showed a significant increased protein synthesis of CD206 (p < 0.05), CD204, and MerTK (p < 0.01), together with a significant upregulation of the gene expression of MerTK and TGFβ1 (p < 0.05; p < 0.01) compared to HS-MDMs. Moreover, the protein synthesis of CD206 and MerTK and the gene expression of TGFβ1 were significantly higher in cultured untreated MDMs from SSc-ILD pts compared to MDMs without ILD (p < 0.05; p < 0.01). In cultured SSc-ILD MDMs, nintedanib 0.1 and 1µM significantly downregulated the gene expression and protein synthesis of CD204, CD206, CD163 (p < 0.05), and MerTK (p < 0.01) compared to untreated cells after 24 h of treatment. Limited to MerTK and IL10, both nintedanib concentrations significantly downregulated their gene expression already after 16 h of treatment (p < 0.05). In cultured SSc-ILD MDMs, nintedanib 0.1 and 1µM significantly reduced the release of active TGFβ1 after 24 h of treatment (p < 0.05 vs. untreated cells).

CONCLUSIONS

In cultured MDMs from SSc-ILD pts, nintedanib seems to downregulate the profibrotic M2 phenotype through the significant reduction of gene expression and protein synthesis of M2 cell surface markers, together with the significant reduction of TGFβ1 release, and notably MerTK, a tyrosine kinase receptor involved in lung fibrosis.

Mikrozirkulationsstörungen der Haut: Microcirculation disorders of the skin

Veränderungen in der Mikrozirkulation der Haut sind ein häufig beobachtetes Begleitphänomen vieler Erkrankungen, weit über das Spektrum dermatologischer Krankheiten hinausreichend. Nicht alle dieser Veränderungen haben einen Krankheitswert, viele treten temporär auf, ohne schwerwiegende Folgen zu verursachen. Dies trifft für viele inflammatorische Erkrankungen wie die Psoriasis vulgaris oder das atopische Ekzem zu.

Daneben gibt es aber auch Erkrankungen, bei denen funktionell und morphologisch erkennbare Mikroangiopathien zu schwerwiegenden Krankheitsfolgen führen. Eine der wichtigsten Erkrankungen in diesem Zusammenhang ist die systemische Sklerose, eine autoimmune Systemerkrankung mit multiplen Organmanifestationen. Hier sind die Untersuchungen der kutanen Mikrozirkulation sowohl in der Erstdiagnose als auch in der Prognose‐ und Verlaufsbeurteilung von weitreichender Bedeutung.

Auch bei Erkrankungen der peripheren Hämodynamik wie der peripheren arteriellen Verschlusskrankheit (pAVK) und der chronisch venösen Insuffizienz (CVI) spielt das Verständnis von Mikrozirkulationsstörungen eine wichtige Rolle für die Therapie und die Erfolgskontrolle therapeutischer Interventionen.

Microvascular status in juvenile Sjögren's disease: the first nailfold videocapillaroscopy investigation

INTRODUCTION

Juvenile Sjögren's disease (jSjD) is a rare autoimmune disease characterized by exocrine gland involvement and systemic manifestations, including small vessel vasculitis and Raynaud's phenomenon (RP). We aimed to investigate the microvascular status in jSjD patients by nailfold videocapillaroscopy (NVC) and the potential correlations with clinical and serological features.

METHODS

Clinical data from thirteen consecutive jSjD patients (11 females and 2 males), with a mean age of 16 ± 4 years, diagnosed before 16 years of age (mean age at diagnosis 12 ± 3) according to the 2016 American College of Rheumatology/EULAR criteria for adult SjD, were collected including age- and sex-matched healthy controls (HCs). Clinical, laboratory, and instrumental data were collected, together with NVC examination. Non-specific and specific NVC parameters were investigated, such as capillary density, capillary dilations, giant capillaries, microhaemorrhages and abnormal shapes. Associations between NVC findings and clinical/serological features were explored and analysed using parametrical and non-parametrical tests.

RESULTS

Capillary density reduction correlated significantly with articular involvement (arthralgias) (p = 0.024). Microhaemorrhages correlated with lower C3 levels (p = 0.034). No specific NVC pattern for jSjD was identified, whereas abnormal capillary shapes were significantly higher in jSjD patients than HCs (p = 0.005). NVC abnormalities were not associated with SjD-specific instrumental tests (biopsy, imaging, Schirmer's test). RP was present in 8% of jSjD patients.

CONCLUSIONS

The reduction of capillary density, as well as microhaemorrhages at NVC analysis, are significantly associated with some clinical aspects like articular involvement and serum biomarkers (C3 reduction). The NVC is suggested as safe and further analysis in jSjD patients.

Microcirculation disorders of the skin

Changes in the microcirculation of the skin are a frequently observed accompanying phenomenon of many diseases, far beyond the spectrum of dermatological diseases. Not all of these changes are pathological, many are transient and have no serious consequences. This is true for many inflammatory diseases such as psoriasis vulgaris or atopic eczema. However, there are also diseases in which functionally and morphologically recognizable microangiopathies lead to severe disease consequences. One of the most important diseases in this context is systemic sclerosis, an autoimmune systemic disease with multiple organ manifestations. Investigations of the cutaneous microcirculation are of great importance for the initial diagnosis as well as for prognosis and assessment of disease progression. In peripheral hemodynamic disorders such as peripheral arterial disease (PAD) and chronic venous insufficiency (CVI), understanding microcirculatory disturbances also plays an important role in therapy and in monitoring the success of therapeutic interventions.

pH-Responsive NIR-II phototheranostic agents for in situ tumor vascular monitoring and combined anti-vascular/photothermal therapy

Developing nanoplatforms integrating superior fluorescence imaging ability in second near-infrared (NIR-II) window and tumor microenvironment responsive multi-modal therapy holds great potential for real-time feedback of therapeutic efficacy and optimizing tumor inhibition. Herein, we developed a pH-sensitive pyrrolopyrrole aza-BODIPY-based amphiphilic molecule (PTG), which has a balanced NIR-II fluorescence brightness and photothermal effect. PTG is further co-assembled with a vascular disrupting agent (known as DMXAA) to prepare PTDG nanoparticles for combined anti-vascular/photothermal therapy and real-time monitoring of the tumor vascular disruption. Each PTG molecule has an active PT-3 core which is linked to two PEG chains via pH-sensitive ester bonds. The cleavage of ester bonds in the acidic tumor environment would tricker releases of DMXAA for anti-vascular therapy and further assemble PT-3 cores into micrometer particles for long term monitoring of the tumor progression. Furthermore, benefiting from the high brightness in the NIR-II region (119.61 M-1 cm-1) and long blood circulation time (t1/2 = 235.6 min) of PTDG nanoparticles, the tumor vascular disrupting process can be in situ visualized in real time during treatment. Overall, this study demonstrates a self-assembly strategy to build a pH-responsive NIR-II nanoplatform for real-time monitoring of tumor vascular disruption, long-term tracking tumor progression and combined anti-vascular/photothermal therapy.

Further insight into systemic sclerosis from the vasculopathy perspective

Systemic sclerosis (SSc) is an autoimmune disease characterized by immune dysfunction, vascular system dysfunction, and tissue fibrosis. Vascular injury, vascular remodeling, and endothelial dysfunction are the hallmark pathological changes of the disease. In the early stages of SSc development, endothelial cell injury and apoptosis can lead to vascular and perivascular inflammation, oxidative stress, and tissue hypoxia, which can cause clinical manifestations in various organs from the skin to the parenchymal organs. Early diagnosis and rational treatment can improve patient survival and quality of life. Ancillary examinations such as nailfold capillaroscopy as well as optical coherence tomography can help early detect vascular injury in SSc patients. Studies targeting the mechanisms of vascular lesions will provide new perspectives for treatment of SSc.

GRB2 serves as a viable target against skin fibrosis in systemic sclerosis by regulating endothelial cell apoptosis

BACKGROUND

Systemic Sclerosis (SSc) is an autoimmune disease characterized by vascular and immune system dysfunction, along with tissue fibrosis. Our previous study found GRB2 was downregulated by salvianolic acid B, a small molecule drug that attenuated skin fibrosis of SSc.

OBJECTIVES

Here we aim to investigate the role of GRB2 in SSc.

METHODS

The microarray data of SSc skin biopsies in Caucasians were obtained from the Gene Expression Omnibus (GEO) database. The expression of GRB2 was further detected in Chinese SSc and healthy controls. Bleomycin (BLM)-induced skin fibrosis mice were used to explore how GRB2 downregulation affected fibrosis. The apoptosis of EA.hy926 endothelial cells was induced by H2O2 and apoptosis ratio was measured by flow cytometric. Transcriptome and phosphoproteomic analyses were performed to explore the regulated pathway.

RESULTS

The expression of GRB2 was significantly enhanced in SSc patient skin, 1.51-fold in Caucasians and 1.40-fold in Chinese. Double immunofluorescence staining showed the endothelial cells of SSc patient's skin highly expressed GRB2. The in vivo study revealed that GRB2 knockdown alleviated skin fibrosis and apoptosis of endothelial cells in BLM mouse skin. The in vitro study showed that GRB2 downregulation inhibited the apoptosis of EA.hy926 and protected them from H2O2-induced hyperpermeability. Moreover, transcriptome and phosphoproteomic analysis suggested the focal adhesion pathway was enriched in GRB2 siRNA transfected endothelial cells.

CONCLUSIONS

Our results demonstrated GRB2 highly expressed in endothelial cells of SSc skin, and inhibiting GRB2 could effectively attenuate BLM-induced skin fibrosis and endothelial cell apoptosis. GRB2 is expected to be a new therapeutic target for SSc.

Naru-3 inhibits inflammation, synovial hyperplasia, and neovascularization in collagen-induced arthritis in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Naru-3 is a prescribed formulation based on the theory of Mongolian medicine for the treatment of rheumatoid arthritis (RA). Naru-3 consists of three medicinal agents: Aconitum kusnezoffii Reichb (caowu), Terminalia chebula Retz (hezi), and Piper longum L (biba). These medicinal agents are widely distributed in the Mongolian area of China and have been used to treat rheumatism for centuries.

BACKGROUND

Mongolian medicine Naru-3 is commonly prescribed to treat RA, but its mechanism of action is unknown.

METHODS

A rat collagen-induced arthritis (CIA) model was established to investigate the mechanism of Naru-3. Rats were treated with Naru-3, Etanercept (ETN), and sodium carboxymethylcellulose (CMC) for four weeks. After treatment was terminated, paw thickness, ankle diameter, and arthritis index (AI) were scored. Synovial hyperplasia was evaluated using hematoxylin and eosin (H&E) staining and two-dimensional ultrasonography. Synovitis and neovascularization were assayed using power Doppler imaging (PDI) and contrast-enhanced ultrasonography (CEUS). Levels of vascular endothelial growth factor (VEGF), interleukin (IL)-1, and CD31 in the serum or synovium were detected using ELISA and immunohistochemistry analyses.

RESULTS

Naru-3 and ETN alleviated the symptoms of CIA as evidenced by diminished paw thickness, ankle diameter, and AI scores. Mechanistically, Naru-3 inhibited synovial hyperplasia, synovitis, and neovascularization by diminishing systemic and local inflammation, as indicated by the relative expression of CD31, VEGF and IL-1 in the serumor synovium. After four weeks of treatment, no significant neovascularization was observed in the Naru-3 group, but neovascularization and synovitis occurred in the ETN group, as demonstrated by H&E staining, PDI, and CEUS examination.

CONCLUSION

Naru-3 inhibited inflammation, synovial hyperplasia, and neovascularization and alleviates RA in our CIA rat model. No symptom recurrence was observed four weeks after drug treatment.

Microvascular damage in autoimmune connective tissue diseases: a capillaroscopic analysis from 20 years of experience in a EULAR training and research referral centre for imaging

OBJECTIVE

Nailfold videocapillaroscopy (NVC) allows the detection of microvascular damage in autoimmune connective tissue diseases (CTDs). The prevalence of the morphological capillary findings was retrospectively evaluated in a wide cohort of patients with Raynaud's phenomenon secondary to a CTD at the time of the first single NVC, independently from their current treatment, autoantibody profile and comorbidities.

METHODS

One-thousand-one-hundred-eighty-one patients affected by CTDs were included from 2001 to 2021. The considered CTDs were systemic sclerosis (SSc), undifferentiated connective tissue disease (UCTD), mixed connective tissue disease (MCTD), dermatomyositis (DM), systemic lupus erythematosus, Sjögren's syndrome and primary antiphospholipid syndrome (aPS). The capillaroscopic parameters were distinguished between scleroderma patterns and non-scleroderma patterns.

RESULTS

Giant capillaries were significantly more frequent in SSc, DM and MCTD than in other CTDs (respectively, in 73%, 73% and 61% of patients, p<0.001 when comparing each rate vs the other CTDs). The mean capillary count was significantly lower in SSc, DM and MCTD (respectively, 7.04±0.18 vs 6.5±0.75 vs 7.7±2 capillaries/linear mm) compared with the other CTDs (p<0.001 for each rate vs the other CTDs). The non-specific abnormalities of capillary morphology were significantly more frequent in SSc, MCTD and aPS (respectively, in 48%, 41% and 36% of cases, all p<0.001 vs each other CTDs).

CONCLUSION

This large size sample of patients with CTDs, collected over 20 years of analysis, confirms the highest prevalence of specific capillaroscopic alterations in patients with SSc, DM and MCTD, when compared with other CTDs.

Nailfold Videocapillaroscopy in Patients with Rheumatoid Arthritis and Psoriatic Arthropathy on ANTI-TNF-ALPHA Therapy

Videocapillaroscopy is a simple, non-invasive investigation that allows the "in vivo" study of the nailfold capillaries. This method is inexpensive, easily accepted by patients and the results can be easily interpreted. It is mainly used in patients with Raynaud's phenomenon and systemic sclerosis, but this examination can also be performed on patients who are suspected of having microcirculation alterations, such as rheumatoid arthritis and psoriatic arthritis. It may aid in the diagnosis, evaluation and prognosis of other rheumatic diseases, besides systemic sclerosis. The aim of this study is to identify the nailfold videocapillaroscopic abnormalities in rheumatoid arthritis and psoriatic arthritis patients and analyze the correlation between their evolution and 12 months of anti-TNF-α therapy. The abnormal capillaroscopic findings comprised widened, dilated or giant capillaries and the distortion of the normal nailfold architecture, avascular areas, hemorrhages and neoangiogenesis. Overall, capillary density, dilated capillaries, giant capillaries, elongated capillaries and angiogenesis significantly improved after 12 months. Moreover, no avascular areas were found after 12 months of anti-TNF treatment.

Training the Next Generation of Rheumatologists: What Is the Best Way to Teach Fellows About Scleroderma?

Rheumatology is rich in educational opportunities, learning about a variety of diseases. Rheumatology subspecialty training is a time of unparalleled learning, and within the curriculum of a training program, the connective tissue diseases (CTDs) represent a unique challenge to the fellows. The challenge therein lies in the multisystem presentations they are faced with mastering. Scleroderma, as a rare and life-threatening CTD, remains one of the most difficult conditions to manage and treat. In this article, the authors focus on an approach to training the next generation of rheumatologists to take care of patients with scleroderma.

Description of Peripheral Blood Perfusion by Laser Speckle Contrast Analysis (LASCA) in 'Early' versus 'Clinically Overt' Systemic Sclerosis in Routine Clinics

OBJECTIVE

To investigate in an unselected, systemic sclerosis (SSc) cohort if baseline laser speckle contrast analysis (LASCA) peripheral blood perfusion (PBP) measurements differ between 'early' SSc (without skin involvement, or 'limited' SSc-LSSc) and 'clinically overt' SSc (with skin involvement, limited cutaneous SSc-LcSSc and diffuse cutaneous SSc-DcSSc) in routine setting.

METHODS

A group of twenty consecutive 'early' SSc patients and forty consecutive 'clinically overt' SSc patients (twenty LcSSc and twenty DcSSc) underwent clinical and LASCA examinations (to assess the peripheral blood perfusion [PBP] of both hands volar).

RESULTS

No statistically significant difference in adjusted PBP was found in the 'early' versus the 'clinically overt' group (p = 0.77) when adjusted for possible confounding factors (e.g., vasoactive medication, active smoking, history of DTL and disease duration). A wide variability was noted when observing the individual datapoints of each subset.

CONCLUSION

This study with an unselected SSc population in daily routine, non-research setting, showed there was no difference in adjusted PBP at baseline between 'early' SSc and 'clinically overt' SSc when corrected for possible confounding factors. Interestingly a wide variation of individual datapoints were observed in each subset, which emphasizes the heterogeneity of SSc.

Pyrrolopyrrole aza-BODIPY-based NIR-II fluorophores for in vivo dynamic vascular dysfunction visualization of vascular-targeted photodynamic therapy

Real-time monitoring vascular responses is crucial for evaluating the therapeutic effects of vascular-targeted photodynamic therapy (V-PDT). Herein, we developed a highly-stable and bright aggregation induced emission (AIE) fluorophore (PTPE3 NP) for dynamic fluorescence (FL) imaging of vascular dysfunction beyond 1300 nm window during V-PDT. The superior brightness (ϵ_maxΦ_{f>1000 nm} ≈ 180.05 M^-1 cm^-1) and high resolution of PTPE3 NP affords not only high-clarity images of whole-body and local vasculature (hindlimbs, mesentery, and tumor) but also high-speed video imaging for tracking blood circulation process. By virtue of the NPs' prolonged blood circulation time (t_1/2 ≈ 86.5 min) and excellent photo/chemical (pH, RONS) stability, mesenteric and tumor vascular dysfunction (thrombosis formation, vessel occlusion, and hemorrhage) can be successfully visualized during V-PDT by FL imaging for the first time. Furthermore, the reduction of blood flow velocity (BFV) can be monitored in real time for precisely evaluating efficacy of V-PDT. These provide a powerful approach for assessing vascular responses during V-PDT and promote the development of advanced fluorophores for biological imaging.

A machine learning model identifies patients in need of autoimmune disease testing using electronic health records

Systemic autoimmune rheumatic diseases (SARDs) can lead to irreversible damage if left untreated, yet these patients often endure long diagnostic journeys before being diagnosed and treated. Machine learning may help overcome the challenges of diagnosing SARDs and inform clinical decision-making. Here, we developed and tested a machine learning model to identify patients who should receive rheumatological evaluation for SARDs using longitudinal electronic health records of 161,584 individuals from two institutions. The model demonstrated high performance for predicting cases of autoantibody-tested individuals in a validation set, an external test set, and an independent cohort with a broader case definition. This approach identified more individuals for autoantibody testing compared with current clinical standards and a greater proportion of autoantibody carriers among those tested. Diagnoses of SARDs and other autoimmune conditions increased with higher model probabilities. The model detected a need for autoantibody testing and rheumatology encounters up to five years before the test date and assessment date, respectively. Altogether, these findings illustrate that the clinical manifestations of a diverse array of autoimmune conditions are detectable in electronic health records using machine learning, which may help systematize and accelerate autoimmune testing.

Involvement of the secosteroid vitamin D in autoimmune rheumatic diseases and COVID-19

Evidence supporting the extra-skeletal role of vitamin D in modulating immune responses is centred on the effects of its final metabolite, 1,25-dihydroxyvitamin D₃ (1,25(OH)₂D₃, also known as calcitriol), which is regarded as a true steroid hormone. 1,25(OH)₂D₃, the active form of vitamin D, can modulate the innate immune system in response to invading pathogens, downregulate inflammatory responses and support the adaptive arm of the immune system. Serum concentrations of its inactive precursor 25-hydroxyvitamin D₃ (25(OH)D₃, also known as calcidiol) fluctuate seasonally (being lowest in winter) and correlate negatively with the activation of the immune system as well as with the incidence and severity of autoimmune rheumatic diseases such as rheumatoid arthritis, systemic lupus erythematosus and systemic sclerosis. Thus, a low serum concentration of 25(OH)D₃ is considered to be a risk factor for autoimmune rheumatic diseases and vitamin D₃ supplementation seems to improve the prognosis; moreover, long-term vitamin D₃ supplementation seems to reduce their incidence (i.e. rheumatoid arthritis). In the setting of COVID-19, 1,25(OH)₂D₃ seems to downregulate the early viral phase (SARS-CoV-2 infection), by enhancing innate antiviral effector mechanisms, as well as the later cytokine-mediated hyperinflammatory phase. This Review provides an update of the latest scientific and clinical evidence concerning vitamin D and immune response in autoimmune rheumatic diseases and COVID-19, which justify the need for monitoring of serum 25(OH)D₃ concentrations and for appropriate supplementation following clinical trial-based approaches.

Emerging nailfold capillaroscopic patterns in COVID-19: from acute patients to survivors

The SARS-CoV-2 infection causing the Coronavirus disease-19 (COVID-19) is characterized by a broad range of clinical manifestations, implicating microvascular damage with endothelial dysfunction and different organ involvement.

Nailfold capillaroscopy

Nailfold capillaroscopy is a safe and well-established method for the assessment of structural alterations of the microcirculation. It is a crucial tool in the investigation and monitoring of patients presenting with Raynaud's phenomenon. Detection of the characteristic "scleroderma pattern" on capillaroscopy may indicate an underlying rheumatic disease, particularly systemic sclerosis (SSc). Herein, we highlight the practical aspects of videocapillaroscopy, including image acquisition and analysis, with mention of dermoscopy. Special emphasis is placed on standardized use of terminology to describe capillary characteristics. Systematic evaluation of images in discerning the normal from the abnormal using the validated European Alliance of Associations for Rheumatology (EULAR) Study Group consensus reporting framework is paramount. In addition to the relevance of capillaroscopy in the (very) early diagnosis of SSc, its emerging predictive value (especially capillary loss) for new organ involvement and disease progression is underscored. We further provide capillaroscopic findings in selected other rheumatic diseases.

Ultrasound quantitative assessment of ventral finger microvasculopathy in systemic sclerosis with Raynaud's phenomena: a comparative study

OBJECTIVE

To assess the finger vascularity of systemic sclerosis patients with Raynaud's phenomenon (RP-SSc) using various ultrasound techniques.

METHODS

All fingers (except thumbs) of 18 RP-SSc patients and 18 controls were imaged at room temperature using four ultrasound vascular imaging techniques. The percent vascular area was quantified by counting blood flow pixels in a 25 mm² square centred at the nail fold for the dorsal side and in 25 mm² and 100 mm² square from the fingertip for the ventral side. The mean vascular intensity was calculated from the corresponding areas for dorsal and ventral sides.

RESULTS

The percent vascular areas and mean vascular intensities in RP-SSc were significantly lower than those in controls for both dorsal and ventral sides (p<0.01). The mean vascular intensities showed slightly higher area under the curve (AUC) than the percent vascular areas (0.53-0.91 vs 0.53-0.90) regardless of imaging technique and assessment side. For each imaging technique, the ventral side vascularity showed a higher AUC (0.74-0.91) compared with the dorsal side (0.53-0.81). Moreover, ventral side abnormalities were associated with a history of digital ulcers.

CONCLUSIONS

Ultrasound demonstrated potential to quantify finger vascularity of RP-SSc. The ventral side of the fingers showed a higher accuracy in detecting RP-SSc than the dorsal side.

Systemic sclerosis

Systemic sclerosis, also known as scleroderma, is a rare and complex autoimmune connective-tissue disease. Once considered an untreatable and unpredictable condition, research advancements have improved our understanding of its disease pathogenesis and clinical phenotypes and expanded our treatment armamentarium. Early and accurate diagnosis is essential, while ongoing efforts to risk stratify patients have a central role in predicting both organ involvement and disease progression. A holistic approach is required when choosing the optimal therapeutic strategy, balancing the side-effect profile with efficacy and tailoring the treatment according to the goals of care of the patient. This Seminar reviews the multiple clinical dimensions of systemic sclerosis, beginning at a precursor very early stage of disease, with a focus on timely early detection of organ involvement. This Seminar also summarises management considerations according to the pathological hallmarks of systemic sclerosis (eg, inflammation, fibrosis, and vasculopathy) and highlights unmet needs and opportunities for future research and discovery.

Specific Autoantibodies and Microvascular Damage Progression Assessed by Nailfold Videocapillaroscopy in Systemic Sclerosis: Are There Peculiar Associations? An Update

BACKGROUND

Specific autoantibodies and nailfold videocapillaroscopy (NVC) findings are serum and morphological diagnostic hallmarks of systemic sclerosis (SSc) as well as useful biomarkers which stratify the microvascular progression and prognosis of patients.

METHODS

The aim of our narrative review is to provide an update and overview of the link between SSc-related autoantibodies, used in clinical practice, and microvascular damage, evaluated by NVC, by exploring the interaction between these players in published studies. A narrative review was conducted by searching relevant keywords related to this field in Pubmed, Medline and EULAR/ACR conference abstracts with a focus on the findings published in the last 5 years.

RESULTS

Our search yielded 13 clinical studies and 10 pre-clinical studies. Most of the clinical studies (8/13, 61.5%) reported a significant association between SSc-related autoantibodies and NVC patterns: more specifically anti-centromere autoantibodies (ACA) were associated more often with an "Early" NVC pattern, whereas anti-topoisomerase autoantibodies (ATA) more frequently showed an "Active" or "Late" NVC pattern. Five studies, instead, did not find a significant association between specific autoantibodies and NVC findings. Among the pre-clinical studies, SSc-related autoantibodies showed different mechanisms of damage towards both endothelial cells, fibroblasts and smooth muscle vascular cells.

CONCLUSIONS

The clinical and laboratory evidence on SSc-related autoantibodies and microvascular damage shows that these players are interconnected. Further clinical and demographic factors (e.g., age, sex, disease duration, treatment and comorbidities) might play an additional role in the SSc-related microvascular injury whose progression appears to be complex and multifactorial.

Longitudinal MicroSPECT Imaging of Systemic Sclerosis Model Mice with [99mTc]Tc-HYNFA via Folate Receptor Targeting

Noninvasive single-photon emission computed tomography (SPECT) imaging with [^99mTc]Tc-HYNFA via folate receptor (FR) targeting was proposed to assess the inflammation and therapeutic effect of systemic sclerosis (SSc) in model mice. The radiochemical yield and purity of [^99mTc]Tc-HYNFA were over 95%, with a specific activity of about 9.36 ± 0.17 MBq/nmol. At the end of induction, the uptake ratios of bleomycin-injected regions on the back-to-muscle (R/M) and lung-to-muscle (L/M) derived from SPECT images were 7.27 ± 0.50 and 4.25 ± 0.15, respectively. The radioactivity uptakes could be blocked by excessive folic acid (FA), and R/M and L/M obviously decreased to 2.78 ± 0.57 and 2.51 ± 0.79, respectively. R/M (2.22 ± 0.71) and L/M (1.62 ± 0.28) decreased very close to those of the control mice group (R/M = 1.99 ± 0.36, L/M = 1.50 ± 0.14) when macrophages had been depleted in advance. After being treated with cyclophosphamide (CTX) or methotrexate (MTX), R/M and L/M decreased to 3.58 ± 0.52 and 2.03 ± 0.32 (CTX treatment) or 2.48 ± 0.64 and 1.83 ± 0.06 (MTX treatment). R/M and L/M were highly correlated with pathological changes. The trend of hydroxyproline content in lungs at the later non-inflammatory phase of each group was similar to the uptake values of the lung in the 4th week from the beginning of induction. [^99mTc]Tc-HYNFA had an ideal uptake in SSc lesions. R/M and L/M had a high consistency with pathological changes. SPECT imaging-targeted FR could monitor the therapeutic effect of CTX and MTX. It is expected to be an effective means to evaluate SSc.

Nailfold capillaroscopy in the rheumatological current clinical practice in Italy: results of a national survey

This cross-sectional online study was designed by the study group on Capillaroscopy and Microcirculation in Rheumatic Diseases (CAP) of the Italian Society of Rheumatology (SIR) to provide an overview of the management of nailfold capillaroscopy in Italian rheumatology centers. Therefore, SIR distributed the survey to its members in July 2021, and each center's physician with the most expertise in capillaroscopy completed the questionnaire. The survey was completed by 102 centers, with at least one representative from each Italian region. Ninety-three centers perform capillaroscopy, and 52 (56) conduct more than 200 investigations annually. Seventy-eight (84%) of respondents have more than five years of experience with the technique, and 75 centers (80.6%) have received certification from specific national or international training courses. In 85 centers, a videocapillaroscope with 200x magnification is employed (91.4%). The average waiting period for the examination is 2.4 months, and less than 3 months in 64 of the locations (68.8%). The study demonstrates that capillaroscopy is an integral part of both the diagnostic phase of Raynaud's phenomenon and the monitoring of autoimmune connective tissue diseases (CTDs). However, the reporting methods and timing of patient followup are heterogeneous.

Nailfold microvascular abnormalities are associated with a higher prevalence of pulmonary arterial hypertension in patients with MCTD

OBJECTIVE

MCTD manifests with microvasculopathy and overlapping clinical features of SLE, SSc and idiopathic inflammatory myopathies (IIM). The aim of this study was to investigate the clinical significance of microvasculopathy in patients with MCTD using nailfold videocapillaroscopy (NVC).

METHODS

Fifty patients with newly diagnosed and untreated MCTD were enrolled in this multicentre, prospective and observational study. Clinical features and NVC findings were assessed at baseline and after 1 year post-intervention, along with disease controls [SLE (n = 40), SSc (n = 70) and IIM (n = 50)].

RESULTS

All MCTD patients presented Raynaud's phenomenon and were positive for anti-U1 RNP antibodies, and 22.0% (11/50) had pulmonary arterial hypertension (PAH). The prevalence of NVC scleroderma patterns in MCTD was 38.0%, which was lower than SSc (88.6%) but higher than SLE (10.0%). In addition, when we divided MCTD patients into two groups by presence or absence of NVC scleroderma patterns, we found a higher prevalence of PAH in patients with NVC scleroderma patterns. Namely, NVC scleroderma patterns were observed in all MCTD patients with PAH, and in 21.0% of those without PAH. After intensive immunosuppressive therapy, NVC scleroderma patterns disappeared in half of the MCTD patients but were not changed in SSc patients.

CONCLUSIONS

MCTD differed from SLE, SSc and IIM in terms of the prevalence and responsiveness of NVC scleroderma patterns to immunosuppressive therapy. Detection of nailfold microvascular abnormalities in MCTD could contribute to predicting PAH and help us to understand further aspects of the pathogenesis of MCTD.

High-resolution Doppler ultrasound in systemic sclerosis: Analysis of digital arteries and nailfold microvasculature using 18-5 MHz and 33-9 MHz probes

INTRODUCTION

Newly developed Doppler techniques enable the sampling of slow vascular flows and the extrapolation of spectral parameters in distal arterioles. The aim of this study was to investigate the role of spectral analysis performed by means of ultra-high frequency ultrasound (US) in the evaluation of the peripheral vascular bed of systemic sclerosis (SSc) patients.

METHODS

Both hands of 33 patients affected by diffuse cutaneous SSc and 34 volunteers were evaluated with a US machine equipped with 33-9 MHz and 18-5 MHz transducers. Proximal resistive index and the peak systolic velocity (pRI and pPSV, respectively), were calculated at the level of the second interdigital artery. The distal resistive index (dRI) was calculated at the level of a nailfold arteriole of the third finger. All SSc patients had been previously divided into 4 subgroups according to their nailfold videocapillaroscopic (NVC) patterns following accepted criteria.

RESULTS

SSc patients showed a significantly slower systolic velocity at the level of the second interdigital artery (pPSV [SD] = 8.38 [3] cm/s vs pPSV [SD] = 11.14 [4.5] cm/s; P = .005) and a higher dRI (dRI [SD] = 0.65 (0.14) vs dRI [SD] = 0.57 [0.11); P = .0115). No differences were found between the pRI values measured in the SSc patients and those of the controls (pRI [SD] = 0.76 [0.11] vs pRI [SD] = 0.73 [0.12]; P = .359]. The subgroup analysis did not show any significant difference when pPSV, pRI and dRI were compared among NVC morphological patterns.

CONCLUSION

High-resolution Doppler analysis of digital distal arterioles may disclose subtle abnormalities in the downstream microvasculature of SSc patients that could be missed when the examination is performed at a more proximal level and/or using lower Doppler frequencies.

Intimate intertwining of the pathogenesis of hypoxia and systemic sclerosis: A transcriptome integration analysis

OBJECTIVES

Systemic sclerosis (SSc) is an autoimmune disease caused by various pathogenic factors, including hypoxia. Hypoxia stimulates the production of the extracellular matrix to promote fibrosis. However, the integrated function and the underlying mechanism of hypoxia in SSc are unclear.

METHODS

In the present study, we used Agilent SurePrint G3 Human Gene Expression v3 for the transcriptional sequencing of fibroblasts with and without hypoxia to detect differentially expressed genes (DEGs) in hypoxia. We analyzed the results with the transcriptome data of SSc lesions (GSE95065) to select the co-DEGs. Then, Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses were performed on the basis of the co-DEGs using the R package ClusterProfiler, which showed that hypoxia and cross talk of hypoxia with other pathogenic factors are involved in the pathogenesis of SSc. Furthermore, we constructed a protein-protein interaction (PPI) network of co-DEGs and screened two significant functional expression modules.

RESULTS

We identified nine hub genes (ALDH1A1, EGF, NOX4, LYN, DNTT, PTGS2, TKT, ACAA2, and ALDH3A1). These genes affect the pentose phosphate pathway, oxidative stress, and lipolysis.

CONCLUSION

Our study provides insights into the mechanisms underlying the effects of hypoxia on SSc pathogenesis, which will help to better understand SSc pathogenesis and develop new therapeutic strategies for SSc.

Microvascular capillaroscopic abnormalities and occurrence of antinuclear autoantibodies in patients with sarcoidosis

We described nailfold videocapillaroscopy (NVC) findings and estimated the prevalence of serum anti-nuclear (ANA) and extractable nuclear antigen autoantibodies (ENA) in a cohort of sarcoidosis patients, comparing them with adequate healthy controls (HCs) and with primary Raynaud’s phenomenon patients (PRPs). NVC findings were also correlated with the occurrence of autoantibodies, current treatment, laboratory parameters, variables of lung function and whole-body imaging data. Twenty-six patients with sarcoidosis were assessed through NVC, laboratory parameters, pulmonary function tests, chest-X ray and 18- fluorodeoxyglucose positron emission tomography/computed tomography. The NVC parameters and ANA/ENA dosage were recorded also in 30 PRPs and 30 HCs. Sarcoidosis patients showed a higher rate of capillary dilations and nonspecific abnormalities and a lower mean capillary absolute number than PRPs and HCs (p < 0.01 for all comparisons). The prevalence of ANA positivity was higher in patients with sarcoidosis compared with PRPs and HCs (p < 0.02 for both), whereas ENA positivity was detected in one sarcoidosis patient (Ro52). Among sarcoidosis patients, the mean capillary absolute number negatively correlated with the C-reactive protein concentrations and was positively associated with the forced vital capacity percentage. Instead, a negative correlation was detected between serum ACE levels and the presence of capillary dilations (all p < 0.05). Our findings suggest a microvascular involvement in sarcoidosis whose investigation by NVC might be useful for the follow-up of patients displaying RP. Autoantibody positivity in sarcoidosis might suggest autoimmune implications in the disease or the production of autoantibodies reactive to tissue damage.

Kinetics of response to iloprost evaluated by laser speckle contrast analysis in systemic sclerosis

OBJECTIVE

Iloprost (ILO) is recommended for the treatment of systemic sclerosis (SSc) microangiopathy, but there is no common consensus on its optimal dosage. The aim of this study is to evaluate the kinetics of response to ILO administered in a daily outpatient scheme in SSc subjects using laser speckle contrast analysis (LASCA).

METHOD

Adult SSc patients in stable therapy with ILO administered for 6 h for 2 consecutive days every 4 weeks were enrolled. Peripheral finger perfusion was assessed by LASCA. Each patient underwent five LASCA evaluations: before and after each day of ILO (D1pre, D1post, D2pre, and D2post) and after 4 weeks (D30).

RESULTS

Twenty-seven SSc patients (77.8% female, mean age 61.5 years) were enrolled. LASCA showed an increase in perfusion at the end of each ILO course, but on the second day (both D1pre vs D2pre and D2pre vs D2post) the increase was no longer significant in half of the fingers. Moreover, compared to D1post, at the beginning of the second ILO day most of the fingers had already shown a significant reduction in perfusion. After 1 month, there were no statistically significant differences between the perfusion values of D1pre and D30.

CONCLUSION

This LASCA study highlights the transience of the vasoactive effect of ILO, with a perfusion benefit that is completely lost after 1 month. The brevity of the perfusion effect of ILO and the use of LASCA are elements to consider in the design of future SSc trials to determine the optimal ILO dosage.

The shadow zone of capillaroscopy in the classification of the Raynaud's phenomenon

Raynaud's phenomenon (RP) is a frequent clinical finding in the general population that can be observed across multiple medical specialties and nailfold videocapillaroscopy is a first line imaging tool to early differenziate primitive and secondary forms of RP. According to the criteria of LeRoy and Medsger normal nailfold capillaries characterize a primary RP. The recognition of vascular alterations at capillaroscopy is the key to a correct framing of the phenomenon. Capillaroscopy is of significant practical value as it allows a reliable predictive assessment of the developmental risk of the disorder. However, to date, the variety of nomenclature for subjects affected by RP generates uncertainty in patient management and in the possibility of comparing studies. The capillaroscopic findings have a very broad range of normality and a significant presence of non specific microvascular abnormalities are reported also in patients with primary RP. The presence of these non specific vascular changes can make it difficult to differenziate primary and secondary RP. Here we highlight some critical points in the capillaroscopic distinction of primary and secondary RP and relaunch the debate on the classification of the RP because it is likely that what we identify today as the primary RP (pRP) collects different clinical entities with different prognostic significance and different therapeutic needs.

Detailed videocapillaroscopic microvascular changes detectable in adult COVID-19 survivors

Objective

COVID-19 is a multisystem disease that causes endothelial dysfunction and organ damage. Aim of the study was to evaluate the microvascular status in COVID-19 survivors with past different disease severity, in comparison with age and sex-matched primary Raynaud's phenomenon (PRP) patients and control subjects (CNT), including possible effects of concomitant therapies.

Methods

Sixty-one COVID-19 survivors (mean age 58 ± 13 years, mean days from disease onset 126 ± 53 and mean days from recovery 104 ± 53), thirty-one PRP patients (mean age 59 ± 15 years, mean disease duration 11 ± 10 years) and thirty CNT (mean age 58 ± 13 years) underwent nailfold videocapillaroscopy (NVC) examination. The following capillaroscopic parameters were searched and scored (0–3): dilated capillaries, giant capillaries, isolated microhemorrhages, capillary ramifications (angiogenesis) and capillary number, including absolute capillary number per linear millimeter at the nailfold bed.

Results

The mean nailfold capillary number per linear millimeter was significantly lower in COVID-19 survivors when compared with PRP patients and CNT (univariate and multivariate analysis p < 0.001). On the contrary, COVID-19 survivors showed significantly less isolated microhemorrhages than PRP patients and CNT (univariate and multivariate analysis, p = 0.005 and p = 0.012, respectively). No statistically significant difference was observed between COVID-19 survivors and control groups concerning the frequency of dilated capillaries and capillary ramifications. COVID-19 selective therapies showed a promising trend on preserving capillary loss and deserving further investigations.

Conclusions

SARS-CoV-2 seems to mainly induce a significant loss of capillaries in COVID-19 survivors at detailed NVC analysis in comparison to controls. The presence of a significant reduced score for isolated microhaemorrhages in COVID-19 survivors deserves further analysis.

Microvasculopathy-Related Hemorrhagic Tissue Deposition of Iron May Contribute to Fibrosis in Systemic Sclerosis: Hypothesis-Generating Insights from the Literature and Preliminary Findings

Microvascular wall abnormalities demonstrated by nailfold capillaroscopy in systemic sclerosis (SSc) may result in microhemorrhagic deposition of erythrocyte-derived iron. Such abnormalities precede fibrosis, which is orchestrated by myofibroblasts. Iron induces endothelial-to-mesenchymal transition in vitro, which is reversed by reactive oxygen species (ROS) scavengers. The conversion of quiescent fibroblasts into profibrotic myofibroblasts has also been associated with ROS-mediated activation of TGF-β1. Given that iron overload predisposes to ROS formation, we hypothesized that the uptake of erythrocyte-derived iron by resident cells promotes fibrosis. Firstly, we show that iron induces oxidative stress in skin-derived and synovial fibroblasts in vitro, as well as in blood mononuclear cells ex vivo. The biological relevance of increased oxidative stress was confirmed by showing the concomitant induction of DNA damage in these cell types. Similar results were obtained in vivo, following intravenous iron administration. Secondly, using magnetic resonance imaging we show an increased iron deposition in the fingers of a patient with early SSc and nailfold microhemorrhages. While a systematic magnetic resonance study to examine tissue iron levels in SSc, including internal organs, is underway, herein we propose that iron may be a pathogenetic link between microvasculopathy and fibrosis and an additional mechanism responsible for increased oxidative stress in SSc.

Microvascular Imaging as a Novel Tool for the Assessment of Blood Flow Velocity in Patients with Systemic Sclerosis: A Single-Center Feasibility Study

Systemic sclerosis is an autoimmune disease characterized by organ fibrosis and vasculopathy. Almost all patients suffer from Raynaud’s phenomenon. Nailfold video capillaroscopy is the most widely imaging technique available, but flow quantification is impossible. Therefore, novel imaging techniques are of interest. We performed a single-center feasibility study using Microvascular Imaging (MVI) for flow quantification of small fingertip vessels. We compared 20 healthy controls (HCs) with 20 systemic sclerosis (SSc) patients. In HCs, measurements were, on average, statistically significantly higher when combined for all fingers (median 10.68 vs. 6 cm/s, Δ = 4.68 cm/s, p < 0.0001) and for individual fingers. An optimal cut-off value of peak systolic (PS) velocity of <6.13 cm/s and end-diastolic (ED) velocity of <2.13 cm/s discriminated HCs from SSc. Test characteristics for PS showed excellent sensitivity (0.90, 95% CI 0.70–0.98) and specificity (0.85, 95% CI 0.64–0.95; LR + 6.0). For ED velocity, sensitivity was 0.85 (95% CI 0.64–0.95) and specificity was 0.80 (95% CI 0.58–0.92, LR + 4.25). Here, we present the first study on the use of MVI to assess blood flow in the fingertips with high sensitivity and specificity in SSc. Future studies are needed to investigate correlations with the risk of organ complications, such as digital ulcers or pulmonary arterial hypertension.

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.

Raynaud's Phenomenon: Reviewing the Pathophysiology and Management Strategies

Raynaud's phenomenon (RP) is a multifactorial vasospastic disorder characterized by a transient, recurrent, and reversible constriction of peripheral blood vessels. RP is documented to affect up to 5% of the general population, but variation in its prevalence is commonly recognized owing to many factors, including varied definitions, gender, genetics, hormones, and region. Furthermore, RP may be idiopathic or be a clinical manifestation of an underlying illness. Patients with RP classically describe a triphasic discoloration of the affected area, beginning with pallor, followed by cyanosis, and finally ending with erythema. This change in color spares the thumb and is often associated with pain. Each attack may persist from several minutes to hours. Moreover, the transient cessation of blood flow in RP is postulated to be mediated by neural and vascular mechanisms. Both structural and functional alterations observed in the blood vessels contribute to the vascular abnormalities documented in RP. However, functional impairment serves as a primary contributor to the pathophysiology of primary Raynaud's. Substances like endothelin-1, angiotensin, and angiopoietin-2 play a significant role in the vessel-mediated pathophysiology of RP. The role of nitric oxide in the development of this phenomenon is still complex. Neural abnormalities resulting in RP are recognized as either being concerned with central mechanisms or peripheral mechanisms. CNS involvement in RP may be suggested by the fact that emotional distress and low temperature serve as major triggers for an attack, but recent observations have highlighted the importance of locally produced factors in this regard as well. Impaired vasodilation, increased vasoconstriction, and several intravascular abnormalities have been documented as potential contributors to the development of this disorder. RP has also been observed to occur as a side effect of various drugs. Recent advances in understanding the mechanism of RP have yielded better pharmacological therapies. However, general lifestyle modifications along with other nonpharmacological interventions remain first-line in the management of these patients. Calcium channel blockers, alpha-1 adrenoreceptor antagonists, angiotensin-converting enzyme inhibitors, nitric oxide, prostaglandin analogs, and phosphodiesterase inhibitors are some of the common classes of drugs that have been found to be therapeutically significant in the management of RP. Additionally, anxiety management, measures to avoid colder temperatures, and smoking cessation, along with other simple modifications, have proven to be effective non-drug strategies in patients experiencing milder symptoms.