Correlations among capillaroscopic abnormalities, digital flow and immunologic findings in patients with isolated Raynaud's phenomenon. Can laser Doppler flowmetry help identify a secondary Raynaud phenomenon?

Thirty subjects with a diagnosis of isolated Raynaud's phenomenon, according to anamnestic and objective criteria, were cross-evaluated by various methods: laser Doppler flowmetry (LDF) during a standardized cold and rewarming test, nailfold capillaroscopy, immunological and other laboratory parameters, to assess the diagnostic and prognostic significance of each method. Correlations were also assessed among disease duration, capillaroscopic pattern score, quantitative digital flow values and laboratory parameters. Nearly 30% of patients showed immunologic abnormalities (ANA positivity at variable titres, ENA, hypocomplementemia, immunocomplexes); 16% of patients had a pathologic capillaroscopic pattern, not well correlated with immunologic findings; a characteristic cold stop reaction of digital flow (partial or total) was detected in 86% of the subjects; in ANA+ pts., ANA titers were positively correlated with the intensity and length of stop reaction (Trec). A significant correlation between digital flow parameters and the capillaroscopic score was also found in each considered group. Our results outline the relevance of LDF, during a standardized thermic test, to evaluate apparently primary RP, because even if a definite scleroderma-like capillaroscopic pattern is absent, this flowmetric method may detect potentially secondary RP patients.