Long-term follow-up of nailfold videocapillaroscopic microvascular parameters in mixed connective tissue disease versus systemic sclerosis patients: a retrospective cohort study.

Objective. To retrospectively study nailfold videocapillaroscopy (NVC) changes in mixed connective tissue disease (MCTD) patients and to compare the capillary morphological abnormalities between patients affected by MCTD and systemic sclerosis (SSc) over time. Methods. Ten MCTD patients on whom NVC had been performed, with a follow- up of three years, were selected. In addition, ten patients affected by SSc with similar age and disease duration of MCTD patients were enrolled to compare NVC abnormalities at baseline (T0). Results. Seven out of ten patients with MCTD showed a “scleroderma-like pattern” at first NVC. No statistically significant variation of the detected NVC parameters was observed during the 3-year follow-up, and no statistically significant correlation was observed between capillary parameters and MCTD clinical aspects at first visit and during the follow-up. The scores of enlarged capillaries, giant capillaries and microhaemorrhages were significantly lower (p<0.05) in MCTD versus SSc patients at T0, moreover, the absolute number of total capillaries and normal capillaries was found significantly higher (p<0.05) in MCTD versus SSc patients. Conclusion. This study suggests that nailfold microvascular damage does not seem to be significantly progressive in MCTD patients during a three-year follow-up. MCTD patients show significantly lower number of enlarged/giant capillaries, but higher number of total and normal capillaries than SSc patients at first nailfold capillaroscopy. The identification of a specific NVC pattern in MCTD patients is not yet possible.