We report on a patient who, at 31 years of age, was found to suffer from sinus histiocytosis with massive lymphadenopathy (SHML; Rosai-Dorfman disease) with nodal and extranodal involvement as described previously. Five years later the patient presented with nephrotic syndrome caused by a generalized AA amyloidosis, and he subsequently died from pulmonary thromboembolism owing to renal vein thrombosis. Retrospective analysis of serum levels of C-reactive protein (CRP) showed that during the last 3 years before his death, he had a persistently elevated CRP level ranging from 73 to 161 mg/L, despite antiinflammatory treatment with prednisolone, methotrexate, or 6-mercaptopurine. These figures indicate that the patient was probably suffering from a permanent acute phase response which, in the absence of any other evidence of a chronic inflammatory disease which commonly causes AA amyloidosis, was most likely owing to SHML.