Nailfold Capillaroscopy Characteristics of Antisynthetase Syndrome and Possible Clinical Associations: Results of a Multicenter International Study

Objective. To describe nailfold videocapillaroscopy (NVC) features of patients with antisynthetase syndrome (AS) and to investigate possible correlations with clinical and serological features of the disease. Methods. We retrospectively analyzed NVC images of 190 patients with AS [females/males 3.63, mean age 49.7 ± 12.8 yrs, median disease duration 53.7 mos (interquartile range 82), 133 anti-Jo1 and 57 non-anti-Jo1-positive patients]. For each patient, we examined number of capillaries, giant capillaries, microhemorrhages, avascular areas, ramified capillaries, and the presence of systemic sclerosis (SSc)-like pattern. Finally, we correlated NVC features with clinical and serological findings of patients with AS. Concomitantly, a historical cohort of 75 patients with antinuclear antibody-negative primary Raynaud phenomenon (RP) and longterm followup was used as a control group (female/male ratio 4.13/1, mean age 53.9 ± 17.6 yrs) for NVC measures. Results. NVC abnormalities were observed in 62.1% of AS patients compared with 29.3% of primary RP group (p < 0.001). An SSc-like pattern was detected in 67 patients (35.3%) and it was associated with anti-Jo1 antibodies (p = 0.002) and also with a longer disease duration (p = 0.004). Interestingly, there was no significant correlation between the presence of SSc-like pattern and RP, and only 47% of patients with SSc-like pattern had RP. Conclusion. NVC abnormalities are commonly observed in AS, independently from the occurrence of RP. The presence of an SSc-like pattern could allow identification of a more defined AS subtype, and prospective studies could confirm the association with clinical and serological features of AS.