LAUSR

Background Raynaud’s phenomenon (RP) is a clinical expression of recurrent reversible vasospasm of small peripheral arteries and arterioles. It is a common pathology in clinical practice and is classified into two main categories – primary RP in the absence of an underlying disorder and secondary RP that is in the context of another disease. The differential diagnosis is of crucial importance for the practising rheumatologists because the patients with primary RP are with benign course while those with secondary RP require further differentiation and establishment of the precise diagnosis and treatment. Differentiation between primary and secondary RP is based on clinical features, laboratory including immunological investigations and capillaroscopic findings. Objectives The nailfold capillaroscopy is a key imaging tool for monitoring the RP patients because of the high predictive value of the abnormal capillaroscopic pattern for future development of connective tissue disease. Patients with primary RP have younger age at onset (<30 years), there are no clinical features of a secondary disease, no trophic changes or abnormal capillaroscopic pattern. Methods Literature data on quantitative analysis of capillaroscopic parameters in primary RP are limited. Results In an own study that included 31 patients with primary RP patients, significantly wider arterial and venous capillary diameters as compared with healthy controls was found in 96.6% of cases. The mean arterial capillary diameter (0.018±0.004 mm) in primary RP patients was significantly larger in comparison healthy volunteers (0.012±0.001 mm, p<0.005). The mean venous capillary diameter was also significantly higher in primary RP (0.026±0.006 mm vs 0.017±0.002 mm in healthy controls, p<0.005).1 Similarly, Bukhari et al. (2000) also observed greater diameters of arterial, venous limb and apical loop in comparison with control subjects in 15 primary RP patients, but the difference was not statistically significant.2 Anderson et al. (2005) also found greater capillary diameters in 21 patients with primary RP vs healthy volunteers but the difference was statistically significant only for the arterial capillary limb and the apex loop but not for the venous capillary diameter.3 Conclusions These capillaroscopic observations in primary RP patients suggest that the absence of an abnormal capillaroscopic pattern is diagnostic for primary RP but minor capillaroscopic dilation is a frequent microvascular feature in these patients. References [1] Lambova S, Müller-Ladner U. Capillaroscopic findings in primary fibromyalgia. Curr Rheumatol Rev2017. doi: 10.2174/1573397113666170607160854. [2] Bukhari M,Hollis S, Moore T, Jayson MI, Herrick AL. Quantitation of microcirculatory abnormalities in patients with primary Raynaud’s phenomenon and systemic sclerosis by videocapillaroscopy. Rheumatology (Oxford)2000;39(5):506–12. [3] Anderson ME, Allen PD, Moore T, Hillier V, Taylor CJ, Herrick AL. Computerized nailfold videocapillaroscopy – a new tool for assessment of Raynaud’s phenomenon. J Rheumatol2005;32:841–8. Disclosure of Interest None declared