What are the principal clinical and laboratory findings that lead a community rheumatologist to refer patients with scleroderma and lupus to a tertiary care center?

From the standpoint of scleroderma or lupus, tertiary care centers are more likely to get referrals from physicians caring for patients with complex, progressive, or refractory disease, though all consults are welcome. I will focus on the scleroderma (a.k.a. systemic sclerosis) aspect of this questi...