Background Increased dermal thickness (DT), decreased peripheral blood perfusion (PBP), and nailfold microangiopathy are typical clinical aspects of systemic sclerosis (SSc) (1-3).

Objectives To investigate possible correlations between DT and both PBP degree and microangiopathy extent in SSc patients.

Methods Forty-four SSc patients (LeRoy 2001 criteria) were enrolled (mean age 64±11SD yrs, mean disease duration 6.7±5 yrs) after informed consent and Ethical Committee approval. DT was measured in SSc patients and in 14 healthy subjects using a high frequency ultrasoundsystem equipped with a 18 MHz probe (and recorded as millimeters), by evaluating the dorsum of middle phalanx of both right and left hand third finger [1]. PBP was analyzed by laser Doppler flowmetry at the central area of the fingertip of the same digits, and the values were recorded as perfusion units (PU) [2]. Nailfold microangiopathy was detected by nailfold videocapillaroscopy (NVC) at the level of the same fingers, and the microangiopathy evolution score (MES) was calculated, as well as the qualitative pattern of microangiopathy (“Early”, “Active” and “Late”) [3–5]. Statistical analysis was performed by non-parametric tests.

Results DT was found significantly higher in SSc patients (median 0.93) when compared with healthy subjects (median 0.77) (p=0.0004). DT was found progressively higher in SSc patients with “Early”, “Active” and “Late” NVC pattern of microangiopathy (median 0.85, 0.90, and 0.95, respectively) (p=0.01), and a positive significant correlation was observed between DT and MES (p=0.01). A positive correlation was also observed between DT and SSc duration (p=0.03). Conversely, a negative correlation was found between DT and PBP (p=0.01). SSc patients with diffuse skin involvement had higher DT than those with limited skin disease (median 1.20 and 0.86, respectively) (p<0.0001). A strong statistically significant correlation was observed between left and right finger DT (p<0.0001). The study confirmed a statistically significant negative correlation between nailfold microvascular damage extent and PBP degree (p<0.0001).

Conclusions This study demonstrates a statistically significant negative correlation between digital DT and PBP degree, as well as a positive correlation between DT and nailfold microvascular damage in SSc patients. Patients showing the “Late“ NVC pattern and/or a high MES score are likely to have greater DT than patients with “Active” or “Early” patterns. The study also confirms a statistically significant negative correlation between nailfold microvascular damage extent and PBP degree.

1. Kaloudi O, et al. Ann Rheum Dis. 2010; 69(6): 1140-3.

2. Cutolo M, et al. J Rheumatol 2010; 37:1174-80.

3. Cutolo, M. et al. Nature Rev Rheumatol 2010; 6, 578–587.

4. Cutolo M, et al. Rheumatology 2004; 43:719-26.

5. Sulli A, et al. Ann Rheum Dis 2008;67:885-7.

Disclosure of Interest None Declared