Serum hyperviscosity syndrome responding to therapeutic plasmapheresis in a patient with primary Sjögren's syndrome.

Hyperviscosity syndrome is a disorder first described in patients with Waldenström's macroglobulinemia and is not commonly seen in rheumatic diseases. Its association with Sjögren's syndrome is very rare and it has been reported in very few patients. We report the case of a patient with primary Sjögren's syndrome presenting as hyperviscosity syndrome who was successfully treated with therapeutic plasma exchange.