Background Lung involvement is the major cause of mortality in patients with systemic sclerosis (SSc). Gas transfer (DLCO) and FVC levels have traditionally been used as measures of disease severity and reductions of both parameters have been associated with increased mortality. In SSc repeated attacks of Raynaud's phenomenon lead to the reduced capillary density leads with reduced blood flow and tissue ischemia. Raynaud's phenomenon can occur also in the lungs. Tissue hypoxia usually initiates the formation of new blood vessels from the pre-existing microvasculature. Nailfold capillaroscopy is a safe, noninvasive routine way for the microvascular investigation.
Objectives The aim of this study was to assess the correlation between capillaroscopic abnormalities and parameters of interstitial lung involvement at baseline and after one year follow-up in patients with SSc.
Methods All patients underwent routine clinical examination (dyspnea, cough, crepitus), pulmonary function tests, DLCO (alveolitis grade and fibrosis), blood gases and HRCT scan of chest (1). Microvasculature changes were assessed using nailfold videocapillaroscopy (NVC) which was performed by two independent examiners. The obtained images were analysed anonymously by two investigators blinded for the clinical and serum status of SSc patients and classified as early, active and late pattern, non specific or normal picture (2). For statistical evaluation Poisson's correlation coefficient and T-test were used. All examinations were performed at baseline and after 12 months.
Results Total 42 patients (38 females) were investigated: 30 individuals with limited form, 7 with diffuse form, 3 patients with scleroderma sine scleroderma, 1 with overlap syndrome and 1 with undifferentiated connective tissue disease. The mean age ± standard deviation (SD) of the whole cohort was 51±22 years and the mean disease duration ± SD was 10±7 years. 3 patients (7.5%) had early NVC pattern, 12 patients (30%) had active, 10 (58%) late pattern, and 17 (37.5%) had nonspecific changes or normal picture. The patients with late NVC pattern exhibited more often mild to moderate alveolitis, decreased FEV1 and FVC and DLCO. When correlating NVC patterns with clinical findings, pulmonary function test and HRCT scans we found only an association of low significance with dyspnea and alveolitis grade (both p<0.1). After one year follow-up similar results were obtained (p<0,001 and p<0,01, respectively).
Conclusions In our study NVC patterns did not seem to correlate with severity of interstitial lung disease in SSc patients even after one year follow-up.
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Acknowledgements This study was performed with support of CMH Research Projects No 00000023728.
Disclosure of Interest None declared