Primary Sjögren's syndrome and gamma heavy chain disease.

We describe a patient who has primary Sjögren's syndrome associated with asymptomatic gamma heavy chain disease and a tubulointerstitial nephritis. Sjögren's syndrome is known to be complicated by lymphoproliferative disorders and tubulointerstitial nephritis but gamma heavy chain disease is rare (approximately 100 cases described). There is one previously reported case of gamma heavy chain disease associated with primary Sjögren's syndrome and 2 cases associated with secondary Sjögren's syndrome. Our patient and the 3 other patients described in the literature did not have evidence of an underlying lymphoproliferative disorder.