Prospective Validation of 5 Items in Nailfold Dermoscopy to Predict a Normal Capillaroscopy in Raynaud's Phenomenon

Raynaud's phenomenon (RP) is very frequent in general population (up to 10%). Nailfold capillaroscopy (NFC) is recommended for patients presenting RP, to eliminate systemic disease such as systemic sclerosis. NFC is not easily available in clinical practice. Dermoscopy, used for pigmentary skin lesion screening, may help to detect giant loops, hemorrhages or other capillaries anomalies. However, no study evaluated the performance of dermoscopy in primary RP. A preliminary study (Tenon Hospital) showed an interest of dermoscopy in primary and secondary RP, with a negative predictive value of dermoscopy of 100% for capillaroscopy.

This is a prospective, multicentric French study comparing dermoscopy and capillaroscopy in patients attending dermatology or vascular medicine departments for the first evaluation of a RP.

The objective is to determinate which items in dermoscopy are correlated with a normal NFC and predict with a good negative predictive value, a normal NFC in RP patients. The secondary objective is to assess inter-observer reproducibility of dermoscopy in patients with RP.

The main hypothesis is that a normal dermocopy on five items is highly predictive of a normal NFC.

During a first consultation for RP, NFC will be realized with a clinical exam and a biological test (antinuclear antibodies), as official recommendations. Dermoscopy of peri-ungueal area will be realized by another investigator, if possible during the same consultation. Photographs of all fingers, except thumbs, will be made and will be reviewed by another investigator of another center. There will be no follow-up.