Patients with Systemic Sclerosis with and without Overlap Syndrome Show Similar Microvascular Abnormalities

Introduction: Nailfold video capillaroscopy (NVC) is a useful tool for measuring capillary density (CD) and capillary morphology parameters and is mainly used in systemic sclerosis (SSc). Objective: We aimed to assess the prevalence of an SSc pattern and CD in different connective tissue diseases (CTDs). Methods: NVC was performed on 268 patients with CTDs. Control groups consisted of 104 healthy volunteers (HVs) and 36 primary Raynaud’s patients (PRPs). Results: Decreased CD was more prevalent in SSc, systemic lupus erythematosus (SLE), inflammatory myopathies (IIM), and overlap CTD patients compared with both controls. Average CD, the prevalence of decreased CD, and the prevalence of an SSc pattern did not differ significantly between SSc patients with (n = 39) and without (n = 50) overlap syndrome. An SSc pattern was significantly more prevalent in SLE (23%), SSc (82%), IIM (35%), and rheumatoid arthritis (17%) compared with both control groups. The prevalence of an elevated microangiopathy evaluation score (MES) was significantly higher in SLE, SSc, and IIM than in the HVs. Conclusion: The presence of another CTD in SSc did not influence CD or morphology. An SSc pattern may also be present in CTDs other than SSc. The MES is a useful instrument to distinguish between patients with CTDs and controls.