A 23-year-old woman had pain, color changes, and ischemic ulcerations of the fingertips of both hands. History and examination revealed eye and mouth dryness, mild dysphagia, and dilated nailfold capillaries; antinuclear antibodies were positive (≥1:640) in a composite nuclear and nucleolar fine speckled staining pattern, as were anti-Ro52, anti-Ro60, and anti–Scl-70 antibodies. What is the diagnosis and what would you do next?