In systemic sclerosis skin perfusion of hands is reduced and may predict the occurrence of new digital ulcers

Association between oxygen delivery and digital ulcers in systemic sclerosis

OBJECTIVE

Tissue hypoxia due to microvasculopathy is the main cause of digital ulcers (DUs) in systemic sclerosis (SSc). Reduced oxygen delivery (DO2) to the tissues may also contribute to the development of DU. This study was conducted to investigate the association between DO2 and DUs in patients with SSc.

METHODS

In all, 111 patients and 30 healthy controls were enrolled. DO2 was calculated by using the formula; DO2 = Cardiac output × arterial oxygen saturation (SpO2) × serum haemoglobin level × 1.39 × 10. Both right index finger SpO2 measurements (index-SpO2) and highest value of SpO2 (maximum SpO2) obtained among the fingers of the subjects were used for the calculations and DO2 results were adjusted both for weight and body surface area (BSA).

RESULTS

Mean DO2 was lower in SSc patients as compared to controls in all 4 different calculations but the difference was only statistically significant when using index-SpO2 and adjusting for BSA (498 mL/min/m² vs 549 mL/min/m², p = 0.03). There was a strong positive correlation between cardiac output and DO2 calculated by using the index-SpO2 (r = 0.903; p < 0.001). Of the SSc patients, 46 (41.4 %) had DUs within the last 12 months. Patients with DUs had higher mean mRSS, lover mean FVC and more frequently diffuse disease, interstitial lung disease, anti-SCL70 antibody positivity (p < 0.05 for all). No difference was observed in DO2 among DU positive or DU negative groups by any calculation (p > 0.05 for all).

CONCLUSIONS

DO2 in SSc patients seems to be lower than healthy controls. However, DO2 is similar between the patients with and without DUs. Our results suggest that the contribution of DO2 is negligible to the development of DU and support the major role of microvasculopathy in SSc patients with DUs.

Predictive value of laser speckle contrast analysis in systemic sclerosis. A systematic review and pilot study

OBJECTIVES

To assess whether tools to functionally examine the microcirculation, such as laser speckle contrast analysis (LASCA), are predictive of ischaemic digital trophic lesions ([i]DTL) in patients with systemic sclerosis (SSc).

METHODS

First, a systematic review (according to PRISMA) was conducted to identify studies describing a link between LASCA and SSc-related (i)DTL. In the additional pilot study, consecutive SSc patients underwent clinical and LASCA examinations (to assess the peripheral blood perfusion [PBP] of both hands) at enrolment. For one year, a monthly telephone survey was conducted to investigate (i)DTL occurrence. Logistic regression and ROC analysis were performed.

RESULTS

None of the three manuscripts retained through the systematic review examined the predictive value of LASCA for future (i)DTL. In our pilot study, 7/106 (6.6%) SSc patients developed at least one iDTL during follow-up, with PBP not found to be predictive (OR = 0.995, p = .418; ROC-AUC = 0.597). Post hoc, when only patients not taking vasodilators were analysed (n = 57), all three who developed iDTL had an average PBP ≤ 70 PU, while only 9/54 (16.7%) patients without iDTL occurrence had such values.

CONCLUSION

A predictive role of LASCA for (i)DTL has not yet been described in the literature and could also not be attested by our additional pilot study, due to a lower-than-expected iDTL incidence in our day-to-day SSc population in which patients were allowed to continue their vasodilator medication. However, the promising observations in the subgroup of vasodilator-naïve patients encourage further investigation of this potential added value of LASCA.

Definition and application of proximal-distal gradient finger perfusion in systemic sclerosis by laser speckle contrast analysis

OBJECTIVE

In patients with systemic sclerosis (SSc) the perfusion of the fingers shows an alteration of the physiological proximal-distal gradient (PDG). The aim of this study is to provide a generalizable definition of PDG, applying it in a cohort of SSc patients and healthy controls (HC) using laser speckle contrast analysis (LASCA).

METHODS

Adult consecutive SSc patients and HC were enrolled. Peripheral blood perfusion of the hands was evaluated by LASCA, subsequently obtaining 3 different regions of interest: from the distal interphalangeal joint to the fingertip (DIST), from the metacarpophalangeal joint to the distal interphalangeal joint (PROX), and of the whole finger (TOT). A PDG formula independent of both intra- and inter-personal factors was then built. The PDG formula so obtained was: [(DIST × 2.63) - PROX]/TOT.

RESULTS

Ninety-four SSc patients (79.8% female, mean age 58.7 years) were enrolled. Applying the PDG formula, SSc patients revealed mean PDG values significantly lower than HC (1.82 ± 0.44 PU vs 2.70 ± 0.38 PU; p < 0.0001). Patients with a previous history of digital ulcers presented significant lower PDG values (p = 0.002). The ROC curve analysis identified in 2.28 PU the best PDG cut-off value between SSc and HC, with 86% sensibility and 90% specificity.

CONCLUSION

This study provided a PDG formula generalizable to all kind of subjects, applying it in SSc with great sensibility and specificity using LASCA, the best non-invasive imaging technique for the dynamical evaluation of peripheral perfusion. LASCA-PDG appears also as a tool able to identify a subclinical microangiopathic impairment.

Laser speckle contrast analysis predicts major vascular complications and mortality of patients with systemic sclerosis

OBJECTIVES

The aim of study was to evaluate peripheral blood perfusion and the proximal-distal gradient (PDG) of the hands as biomarkers of SSc major vascular complications (digital ulcers, pulmonary arterial hypertension, scleroderma renal crisis) and mortality by laser speckle contrast analysis.

METHODS

In this retrospective observational study, 176 SSc patients [158 female, median age 53 (51-57) years] and 142 healthy controls [115 female, median age 53 (48-55) years] were enrolled. Clinical data were collected at baseline and annually through 5 years of follow-up. Hand dorsum perfusion images were divided into three regions of interest (ROI): ROI1 included the second, third, and fourth fingers distal to the proximal interphalangeal finger joint; ROI2 included the area between the proximal interphalangeal finger joint and the metacarpophalangeal joint; ROI3 included the hand dorsum. PDG was identified when the perfusion mean difference between ROI1 and ROI2 was >30 perfusion units.

RESULTS

Median peripheral blood perfusion was significantly lower for SSc patients than healthy controls. PDG was present in 51.5% of SSc patients and in 98.6% of healthy controls. Using the final multivariate model, nailfold videocapillaroscopy (NVC) pattern [hazard ratio (HR) 0.065 (0.015-0.283), P <0.0001] and PDG [HR 0.376 (0.194-0.727), P <0.01] were found to be risk factors for major vascular complications. By multivariate analysis, age [HR 1.051 (1.014-1.088), P <0.01), NVC pattern [HR 0.001 (0.000-3.111), P >0.05], and PDG [HR 0.207 (0.073-0.589), P <0.01] were found to be risk factors for 5-year SSc mortality.

CONCLUSION

PDG predicts major vascular complication and 5-year mortality of SSc patients.

Correlation between the infrared thermogram and microvascular abnormalities of the nailfold in patients with systemic sclerosis

INTRODUCTION

Systemic sclerosis (SSc) is a multisystemic disease with an extensive microvasculopathy. The gold standard for its investigation is nailfold videocapillaroscopy (NVC).

AIM

To assess the value of thermography (IRT) for the assessment of microvasculopathy in patients with SSc.

MATERIAL AND METHODS

Nineteen patients with limited cutaneous SSc were enrolled in the study. They underwent IRT imaging and NVC. An average temperature (Tavg) at the nailfold and a gradient of temperatures (ΔTavg) between the central metacarpus of the hand and the nailfold was determined for all fingers. NVC pictures were classified to capillaroscopic patterns according to Cutolo et al. system and they were analysed quantitatively to measure the density of capillaries and to calculate capillaroscopic skin ulcers risk index (CSURI) for each finger separately.

RESULTS

There was only a moderate correlation (0.4 < r < 0.6) between thermographic parameters and density of capillaries in fingers II-V (r = 0.5; p < 0.001 for Tavg and r = -0.45; p < 0.001 for ΔTavg), but none in thumbs (r = 0.29; p = 0.089 for Tavg and r = -0.19; p = 0.275 for ΔTavg). Early pattern was associated with a significantly greater surface temperature (Tavg) of nailfolds and essentially milder ΔTavg in fingers II-V when compared to all other capillaroscopic patterns in fingers II-V. Surface temperature (Tavg) was significantly lower and ΔTavg was markedly more pronounced in fingers II-V with a greater risk of development of digital ulcers (DU) calculated by CSURI.

CONCLUSIONS

Although IRT measurements correlate only moderately with density of capillaries, this technique seems to be substantial to determine the capillaroscopic pattern and to identify patients at greater risk of DU development.

New perspectives in the imaging of Raynaud's phenomenon

The last 10-20 years have seen huge strides in imaging science. The aim of this review article is to share with the reader the key recent advances in non-invasive imaging of the digital (finger) vasculature in patients with Raynaud's phenomenon (RP), including in systemic sclerosis (SSc)-related digital vasculopathy. For the rheumatologist, seeing a patient with RP is an opportunity for early diagnosis of an underlying SSc-spectrum disorder or (conversely) for reassuring the patient with primary (idiopathic) RP. Non-invasive imaging techniques can help to provide diagnostic certainty. In addition, they can provide new insights into pathophysiology and have the potential to facilitate the development of much needed effective treatments by providing primary and secondary endpoints for randomized controlled trials: validation studies are ongoing. This review article focuses on nailfold capillaroscopy, thermography, and laser Doppler methods but also discusses (briefly) other technologies, including optical coherence tomography, multispectral imaging, and photoacoustic imaging. Key recent advances are the increasing use/availability of nailfold capillaroscopy (and better understanding of the role of low-cost hand-held devices), increased accessibility of thermography (including mobile phone thermography), and increased application of laser Doppler methods to the study of RP/digital vasculopathy (in particular of laser Doppler imaging and laser speckle contrast imaging, both of which measure blood flow over an area rather than at a single site). In an era of precision medicine, non-invasive imaging techniques can help stratify risk of (a) SSc in the patient with RP and (b) digital vascular disease progression in the patient with an SSc-spectrum disorder.

Alterations in Skin Blood Flow at the Fingertip Are Related to Mortality in Patients With Circulatory Shock

OBJECTIVES

Skin blood flow is rapidly altered during circulatory shock and may remain altered despite apparent systemic hemodynamic stabilization. We evaluated whether changes in skin blood flow during circulatory shock were related to survival.

DESIGN

Prospective study.

SETTING

Thirty-five-bed medical-surgical university hospital department of intensive care.

SUBJECTS

Twenty healthy volunteers and 70 patients with circulatory shock (< 12 hr duration), defined as the need for vasopressors to maintain mean arterial pressure greater than or equal to 65 mm Hg and signs of altered tissue perfusion.

INTERVENTIONS

We assessed skin blood flow using skin laser Doppler on the fingertip for 3 minutes at basal temperature (SBFBT) and at 37°C (SBF37) (thermal challenge test) once in volunteers and at the time of inclusion and after 6, 24, 48, 72, and 96 hours in patients with shock. Capillary refill time and peripheral perfusion index were measured at the same time points on the contralateral hand.

MEASUREMENTS AND MAIN RESULTS

The thermal challenge response (ΔSBF/ΔT) was calculated using the following formula: (SBF37-SBFBT)/(37-basal temperature). Area under the receiver operating characteristic curves were calculated to evaluate variables predictive of ICU mortality. At inclusion, skin blood flow and ΔSBF/ΔT were lower in patients than in volunteers. Baseline skin blood flow (31 [17-113] vs 16 [9-32] arbitrary perfusion units; p = 0.01) and ΔSBF/ΔT (4.3 [1.7-10.9] vs 0.9 [0.4-2.9] arbitrary perfusion unit/s) were greater in survivors than in nonsurvivors. Capillary refill time was shorter in survivors than in nonsurvivors; peripheral perfusion index was similar in the two groups. ΔSBF/ΔT (area under the receiver operating characteristic curve 0.94 [0.88-0.99]) and SBFBT (area under the receiver operating characteristic curve 0.83 [0.73-0.93]) had the best predictive value for ICU mortality with cutoff values less than or equal to 1.25 arbitrary perfusion unit/°C (sensitivity 88%, specificity 89%) and less than or equal to 21 arbitrary perfusion unit (sensitivity 84%, specificity 81%), respectively.

CONCLUSIONS

Alterations in fingertip skin blood flow can be evaluated using a laser Doppler thermal challenge technique in patients with circulatory shock and are directly related to outcome. These novel monitoring techniques could potentially be used to guide resuscitation.

Microvascular involvement in systemic sclerosis and systemic lupus erythematosus

Microvascular changes play central roles in the pathophysiology of SSc and SLE, and represent major causes of morbidity and mortality in these patients. Therefore, clinical tools that can assess the microvasculature are of great importance both at the time of diagnosis and follow-up of these cases. These tools include capillaroscopy, laser imaging techniques, infrared thermography, and iontophoresis. In this review, we examined the clinical manifestations and pathobiology of microvascular involvement in SSc and SLE as well as the methodologies used to evaluate the microvasculature.

Cutaneous Manifestations of Scleroderma and Scleroderma-Like Disorders: a Comprehensive Review

Scleroderma refers to an autoimmune connective tissue fibrosing disease, including three different subsets: localized scleroderma, limited cutaneous systemic sclerosis, and diffuse cutaneous systemic sclerosis with divergent patterns of organ involvement, autoantibody profiles, management, and prognostic implications. Although systemic sclerosis is considered the disease prototype that causes cutaneous sclerosis, there are many other conditions that can mimic and be confused with SSc. They can be classified into immune-mediated/inflammatory, immune-mediated/inflammatory with abnormal deposit (mucinoses), genetic, drug-induced and toxic, metabolic, panniculitis/vascular, and (para)neoplastic disorders according to clinico-pathological and pathogenetic correlations. This article reviews the clinical presentation with emphasis on cutaneous disease, etiopathogenesis, diagnosis, and treatment options available for the different forms of scleroderma firstly and for scleroderma-like disorders, including scleromyxedema, scleredema, nephrogenic systemic fibrosis, eosinophilic fasciitis, chronic graft-versus-host disease, porphyria cutanea tarda, diabetic stiff-hand syndrome (diabetic cheiroartropathy), and other minor forms. This latter group of conditions, termed also scleroderma mimics, sclerodermiform diseases, or pseudosclerodermas, shares the common thread of skin thickening but presents with distinct cutaneous manifestations, skin histology, and systemic implications or disease associations, differentiating each entity from the others and from scleroderma. The lack of Raynaud's phenomenon, capillaroscopic abnormalities, or scleroderma-specific autoantibodies is also important diagnostic clues. As cutaneous involvement is the earliest, most frequent and characteristic manifestation of scleroderma and sclerodermoid disorders, dermatologists are often the first-line doctors who must be able to promptly recognize skin symptoms to provide the affected patient a correct diagnosis and appropriate management.

Combination of Capillaroscopic and Ultrasonographic Evaluations in Systemic Sclerosis: Results of a Cross-Sectional Study

OBJECTIVE

To compare microvascular damages on nailfold capillaroscopy (NFC) with macrovascular manifestations evaluated by hand power Doppler ultrasonography (PDUS) in systemic sclerosis (SSc) patients, and to assess the associations of these damages with the main digital manifestations of the disease: digital ulcers, acroosteolysis, and calcinosis.

METHODS

NFC, hand radiographs, and PDUS were systematically performed in 64 unselected SSc patients. PDUS evaluation with assessment of ulnar artery occlusion (UAO) and finger pulp blood flow (FPBF) were performed blinded for the results of radiographs and NFC.

RESULTS

UAO and pathologic FPBF were associated with severe capillary loss (<4 capillaries/mm) on NFC (odds ratio [OR] 4.04 [95% confidence interval (95% CI) 1.23-13.29]; P < 0.05, and OR 3.38 [95% CI 1.03-11.05]; P < 0.05, respectively). Digital ulcer history was associated with UAO (OR 10.71 [95% CI 3.36-34.13]; P < 0.0001), pathologic FPBF (OR 7.67 [95% CI 2.52-23.28]; P < 0.0001), late NFC pattern (OR 6.33 [95% CI 2.03-19.68]; P = 0.001), and severe capillary loss (OR 8.52 [95% CI 2.15-33.78]; P = 0.001). Acroosteolysis was also associated with UAO (OR 15.83 [95% CI 3.95-63.54]; P < 0.0001), pathologic FPBF (OR 5.52 [95% CI 1.71-17.90]; P = 0.003), late NFC pattern (OR 6.86 [95% CI 2.18-21.53]; P = 0.001), and severe capillary loss (OR 7.20 [95% CI 2.16-24.02]; P = 0.001). Calcinosis on radiographs was associated with late NFC pattern (OR 5.41 [95% CI 1.82-16.12]; P = 0.002), severe capillary loss (OR 12.69 [95% CI 3.14-51.26]; P < 0.0001), and UAO (OR 3.19 [95% CI 1.14-8.92]; P = 0.025). Combination of UAO and severe capillary loss in the same patient was especially associated with digital ulcer history (OR 18.60 [95% CI 2.24-154.34]; P = 0.001) and acroosteolysis (OR 10.83 [95% CI 2.56-45.88]; P = 0.001).

CONCLUSION

Microvascular damages evaluated by NFC and macrovascular features like UAO assessed by PDUS show concordant associations with the main digital manifestations of the disease.