Digital pitting scars are associated with a severe disease course and death in systemic sclerosis: a study from the EUSTAR cohort

High Prevalence of the Lung Ultrasound Interstitial Syndrome in Systemic Sclerosis Patients with Normal HRCT and Lung Function-A Pilot Study

Objective: High-resolution computed tomography (HRCT) may lack sensitivity for the early detection of interstitial lung disease associated with systemic sclerosis (SSc-ILD). Lung ultrasound is an emerging technique for the diagnosis of SSc-ILD. This cross-sectional study aimed to describe the prevalence of ultrasound interstitial syndrome in SSc patients with normal HRCT and pulmonary function tests (PFT). Methods: Thirty SSc patients with normal HRCT, FVC > 80% predicted and DLCO > 70% predicted were included. Echocardiography and PFT including impulse oscillometry and cardiopulmonary exercise testing were performed. Lung ultrasound was analyzed by two blinded operators. Patients were classified into two groups, according to the presence or absence of ultrasound interstitial syndrome, defined as the sum of B-lines in all thoracic areas ≥10 and/or pleural line thickness >3 mm on at least one thoracic area and/or a pleural line irregularity score >16%. Results: Ultrasound interstitial syndrome was present in 12 patients (40%). Inter-reader agreement for the diagnosis of ultrasound interstitial syndrome defined by the Kappa coefficient was 0.93 (95%CI 0.79-1.00). Patients with ultrasound interstitial syndrome were younger (37 years vs. 53 years, p = 0.009), more often had pitting scars (n = 7/12 vs. 3/18, p = 0.045) and had lower FVC (102 vs. 110% pred, p = 0.009), TLC (114 vs. 122% pred, p = 0.042) and low-frequency respiratory system reactance (Xrs5 Z-score 0.16 vs. 1.02, p = 0.018), while pulmonary gas exchange was similar. Conclusions: Ultrasound interstitial syndrome was detected in 12/30 SSc patients with normal HRCT and PFT. Patients with ultrasound interstitial syndrome had differences in lung function consistent with reduced respiratory compliance, suggesting minimal and/or early suspected SSc-ILD.

Calcinosis in systemic sclerosis

PURPOSE OF REVIEW

To provide updated information on the prevalence, pathogenesis, diagnostics, and therapeutics of calcinosis cutis associated with systemic sclerosis (SSc).

RECENT FINDINGS

Observational studies show ethnic and geographical differences in the prevalence of calcinosis. In addition to clinical and serological associations, biochemical studies and in-vivo models have attempted to explain theories behind its pathogenesis, including prolonged state of inflammation, mechanical stress, hypoxia, and dysregulation in bone and phosphate metabolism. Long-term use of proton pump inhibitors may increase the risk for calcinosis in SSc. Few single center observational studies have shown mild benefit with minocycline and topical sodium thiosulfate.

SUMMARY

Calcinosis cutis is the deposition of insoluble calcium in the skin and subcutaneous tissues. It affects up to 40% of SSc patients and causes significant morbidity. Long disease duration, features of vascular dysfunction, and osteoporosis have been associated with calcinosis. Altered levels of inorganic pyrophosphate and fibroblast growth factor-23 have been implicated in dysregulated phosphate metabolism that may lead to calcinosis in SSc. Plain radiography can help with diagnosis and quantifying the calcinosis burden. Surgical treatment remains the most effective therapy when feasible. At present, no medical therapies have proven efficacy in large randomized controlled trials.

MRI Digital Artery Volume Index (DAVIX) as a surrogate outcome measure of digital ulcer disease in patients with systemic sclerosis: a prospective cohort study

BACKGROUND

Vascular fibrosis is a key manifestation of systemic sclerosis that leads to the narrowing of small and medium arteries, causing vascular clinical manifestations including digital ulcers and pulmonary arterial hypertension. We investigated the potential of the MRI-based Digital Artery Volume Index (DAVIX) as a surrogate outcome measure of vascular fibrosis by using it to quantify and predict the burden of digital ulcer disease in patients with systemic sclerosis.

METHODS

Two independent cohorts of patients participating in the prospective observational study STRIKE were consecutively enrolled from the Scleroderma Clinic of the Leeds Teaching Hospitals Trust, Leeds, UK. Eligible patients were aged 18 years or older and fulfilled the very early diagnosis of systemic sclerosis (VEDOSS) or the 2013 American College of Rheumatology (ACR)-European Alliance of Associations for Rheumatology (EULAR) systemic sclerosis classification criteria. DAVIX was calculated as the percentage mean of the ratio of digital artery volume to finger volume in the four fingers of the dominant hand. Data were collected at baseline and 12-month follow-up, and the primary outcome was the presence of digital ulcers at 12-month follow-up.

FINDINGS

Between Feb 7, 2018, and April 11, 2022, we included 85 patients in the exploratory cohort and 150 in the validation cohort. In the exploratory cohort, the mean age was 54·5 years (SD 11·6), 75 (88%) of 85 patients were women, ten (12%) were men, and 69 (82%) were White. In the validation cohort, the mean age was 53·5 years (SD 13·8), 136 (91%) of 150 patients were women, 14 (9%) were men, and 127 (85%) were White. In the exploratory cohort, DAVIX was significantly lower in patients with previous or active digital ulcers (0·34% [IQR 0·16-0·69]) than in those without digital ulcer disease (0·65% [0·42-0·88]; p=0·015); this finding was substantiated in the validation cohort (0·43% [0·20-0·73] vs 0·73% [0·53-0·97]; p<0·0001). Patients who developed new digital ulcers during 12-month follow-up had a lower DAVIX (0·23% [0·10-0·66]) than those who did not (0·65% [0·45-0·91]; p=0·0039). DAVIX was negatively correlated with disease duration (r=-0·415; p<0·0001), the ratio of forced vital capacity to the diffusing capacity of the lungs for carbon monoxide (r=-0·334; p=0·0091), nailfold capillaroscopy pattern (r=-0·447; p<0·0001), and baseline modified Rodnan skin score (r=-0·305; p=0·014) and was positively correlated with the diffusing capacity of carbon monoxide (r=0·368; p=0·0041). DAVIX was negatively correlated with change in score on the Scleroderma Health Assessment Questionnaire-Disability Index (r=-0·308; p=0·024), Visual Analogue Scale (VAS) Raynaud's (r=-0·271; p=0·044), and VAS digital ulcers (r=-0·291; p=0·044).

INTERPRETATION

DAVIX is a promising surrogate outcome measure of digital ulcer disease in patients with systemic sclerosis. The ability of DAVIX to non-invasively predict future digital ulcers and worsening of patient-reported outcomes could aid patient enrichment and stratification in clinical trials. Clinically, DAVIX could offer insights into the assessment of vascular activity. The sensitivity of DAVIX to change over time and with treatment will establish its value as an imaging outcome measure of vascular disease.

FUNDING

National Institute for Health Research Biomedical Research Centre and University of Leeds Industry Engagement Accelerator Fund.

Treatment of Vascular Complications in Systemic Sclerosis: What Is the Best Approach to Diagnosis and Management of Renal Crisis and Digital Ulcers?

Vasculopathy as exemplified by scleroderma renal crisis (SRC) and digital ulcers (DUs) is a cardinal feature of systemic sclerosis (SSc) and is associated with significant morbidity, including in patients with early disease. Prompt recognition and management is required to alleviate potentially irreversible damage from SSc-associated vasculopathy. Both SRC and DUs share many etiopathogenic drivers which inform the therapeutic strategy. The aim of our review was to describe the diagnosis and management of SRC and DUs in SSc, and to discuss unmet needs for future research.

Prevalence of and factors independently associated with digital ischemic complications in patients with systemic sclerosis

Objective

To investigate the prevalence of and independent predictors for digital ischemic complications in patients with systemic sclerosis.

Method

Patients enrolled in the Siriraj Systemic Sclerosis Cohort registry during 2013-2019 were classified as having or not having digital ischemic complications at the baseline and 1-year timepoints.

Results

A total of 171 patients with systemic sclerosis were included. The prevalence of digital pulp loss, digital pitting scar, digital ulcer, and digital amputation at baseline and 1 year was 41.5%, 39.8%, 3.5%, 7.6% and 37.4%, 43.9%, 14.1%, 6.4%, respectively. Over half (58.5%) of overall systemic sclerosis had developed new digital ischemic complications during the 1-year follow-up. Those with digital ischemic complications at baseline were at high risk for developing new digital ischemic complications (odds ratio: 15.9). Diffuse cutaneous systemic sclerosis is associated with digital ischemic complications (odds ratio: 6.0), digital pitting scar (odds ratio: 4.9), and digital pulp loss (odds ratio: 6.4). Tendon friction rub is associated with digital pitting scar (odds ratio: 5.0). Salt-and-pepper skin appearance is associated with digital pulp loss (odds ratio: 3.0) and digital ulcer (odds ratio: 6.9). Disease duration > 3 years is associated with digital ulcer (odds ratio: 4.4). Male gender is associated with digital ulcer (odds ratio: 5.4).

Conclusion

Digital pulp loss, digital pitting scar, digital ulcer, and digital amputation were common manifestations of digital ischemic complications, and diffuse cutaneous systemic sclerosis was the strongest of the six independent predictors.

Calcinosis in systemic sclerosis

PURPOSE OF REVIEW

The aim of this study was to provide updated information on the prevalence, pathogenesis, diagnostics and therapeutics of calcinosis cutis associated with systemic sclerosis (SSc).

RECENT FINDINGS

Observational studies show ethnic and geographical differences in the prevalence of calcinosis. In addition to clinical and serological associations, biochemical studies and in-vivo models have attempted to explain theories behind its pathogenesis, including prolonged state of inflammation, mechanical stress, hypoxia and dysregulation in bone and phosphate metabolism. Long-term use of proton pump inhibitors may increase the risk for calcinosis in SSc. Few single-centre observational studies have shown mild benefit with minocycline and topical sodium thiosulfate.

SUMMARY

Calcinosis cutis is the deposition of insoluble calcium in the skin and subcutaneous tissues. It affects up to 40% of SSc patients and causes significant morbidity. Long disease duration, features of vascular dysfunction and osteoporosis have been associated with calcinosis. Altered levels of inorganic pyrophosphate and fibroblast growth factor-23 have been implicated in dysregulated phosphate metabolism that may lead to calcinosis in SSc. Plain radiography can help with diagnosis and quantifying the calcinosis burden. Surgical treatment remains the most effective therapy when feasible. At present, no medical therapies have proven efficacy in large randomized controlled trials.

The clinical relevance of Raynaud's phenomenon symptom characteristics in systemic sclerosis

Raynaud's phenomenon (RP) is a cardinal feature of systemic sclerosis (SSc) and manifests with pain, digital colour change, sensory symptoms, and impaired function. SSc-RP is exacerbated by cold exposure (RP 'attacks') but many patients report persistent symptoms of background digital ischaemia. The aim of our study was to examine the significance of RP with digital colour change with or without symptoms, and persistent colour change in between attacks. Patients with SSc responses were obtained from the Patient Survey of experiences of Raynaud's Phenomenon (PASRAP). We enquired about symptoms associated with Raynaud's attacks, and persistent symptoms in between attacks. Data were analysed as descriptive statistics with appropriate parametric/non-parametric testing. Relevant PASRAP survey question data from 747 evaluable SSc patients from across three continents were analysed. Isolated colour change was rare (29/484, 6%). Digital ulcers were more common in SSc-RP associated with other sensory symptoms (42.1% vs. 24.1%, P=0.057) and more readily treated with phosphodiesterase-type 5 inhibitors (22.5% vs. 10.3%%, P=0.124). Over one-third of patients (n=92/239, 38%) reported persistent colour change in between Raynaud's attacks. Patients with persistent colour change were more likely to have pulmonary arterial hypertension (15.2% vs. 7.5%, P=0.057) and be treated with calcium channel blockers (54.3% vs. 39.0%, P=0.021). SSc-RP with colour change and other symptoms and/or or persistent decolourisation in between attacks were more likely to have vascular complications of SSc and be treated with vascular therapies. Future research should explore the judicious use of vascular therapies as a potential form of disease modification in SSc. Key Points • Isolated colour change without other symptoms is rare in SSc patients. • SSc patients often identify persistent symptoms in between attacks of RP. • SSc-RP with colour change and other symptoms, or persistent decolourisation, may have greater disease severity and be treated with vascular therapies.