[Two cases of RA-like and SLE-like features similar to remitting seronegative symmetrical synovitis with pitting edema (RS3PE syndrome)].

In 1985, McCarty et al reported 10 patients with a symmetrical synovitis affecting predominately the wrists and flexor digitorum tendon sheaths associated with marked pitting edema of the dorsum of both hands and both feet. It was insisted on the clinical entity as remitting seronegative symmetrical synovitis with pitting edema (RS3PE syndrome). These patients were mostly elderly men whose sera revealed negative rheumatoid factor and had a benign clinical course. Patients with RS3PE syndrome remitted completely within 3-36 months and the remission was maintained even after all medications were discontinued. We experienced 2 interesting cases which were similar to RS3PE syndrome. One case with SLE-like conditions evolved into RA-like conditions. On the contrary, the other which had been effectively treated as RA developed into SLE-like conditions. Both cases were seronegative and had the characteristic pitting edema of both hands and feet demonstrating the symmetrical synovitis without bony erosions. They went into complete remission by corticosteroid therapy, although it did not continue for a long time. We should consider that such cases are similar to RS3PE syndrome and must be distinct from it.